11

CHAPTER 2

REVIEW OF LITERATURE

The review of literature chapter deals with background information about the

thesis. This is divided into 4 major headings such as 1. role of nutraceutical

compounds of amla, 2. amla based products and their changes in nutritional qualities

during processing, 3. amla pieces with spices and 4. amla residue incorporated bread.

The first heading elaborately describe the basic definition for nutraceutical and

functional foods, phyto chemical compounds in the amla as well as the previous

research work in the pharmacology and clinical studies, role of amla in specific

diseases and disorders. The second part of this chapter list out the amla based food

products in detail and the siddha products in short. The third part is for amla pieces

with spices, one of the products developed in this work which will be describing

about the osmotic dehydration process, post harvest technology of amla as well as

the changes in chemical composition of the products occur during the process. The

last part is about the amla residue incorporated bread second product developed in

this work. In this the definition and role of functional foods will be discussed. Here

the functional food base bread will be discussed in detail along with the functional

compound, dietary fibre and its effect on health studied by researchers. The

recommended dietary allowance of dietary fibre by different agencies will also be

discussed.

2.1 ROLE OF NUTRACEUTICAL COMPOUNDS OF AMLA

The first heading of the chapter describes the basic details about amla plant,

fruit, and their beneficial effects are elaborated. Amla is known as a health beneficial

produce. The combined terminology opts for its nutritional and pharmacology effect

is also discussed here. Further the phyto chemical compounds present in the amla

and their occurrence also are discussed. The major compounds responsible for the

health effect of amla and roles are described. The proven facts of amla on different

disorders and diseases are also discussed here.

12

The plant genus Phyllanthus (Euphorbiaceae) is widely distributed in most

tropical and subtropical countries. It is a very large genus consisting of

approximately 550 to 750 species and is subdivided into 10 or 11 subgenera:

Botryanthus, Cicca, Conani, Emblica, Ericocus, Gomphidium, Isocladus,

Kirganelia, Phyllanthodendron, Phyllanthus and Xylophylla [48,49] Phyllanthus

emblica L. is a tree of small or moderate size with a greenish-grey bark and

greenish-yellow flowers, formed in axillary clusters. The feathery leaves are linear-

oblong, with a rounded base and obtuse or acute apex. The tender fruits are green,

fleshy, globose and shining, and change to light yellow or brick-red when

mature. It grows in tropical and subtropical parts of China, India, Indonesia, and on

the Malay Peninsula. The Malaysian variety has more scurfy branchlets and the

immature fruit is top-shaped. The name of the Malacca river and town is believed

to have been derived from the name of this tree. The origin of the name is from

Sanskrit (Melaka, Malaka). In Tamil the tree is known as Nelli, the fruit Nellikai and

in Bangladesh Amlaki, Amla in Hindi, and Yeowkan in Chinese. The fruits are

known as Amalakam and Sriphalam in Sanskrit, Emblic myrobalam and Indian

gooseberry in English, and Phylontha emblic in French.

Its daily intake as fresh or processed form decreases serum cholesterol,

prevents indigestion, controls acidity, liver disorders, premature graying and hair

loss, improves eyesight and purifies blood. The fruit is very sour when you bite it.

But after a few minutes, after it mixes with saliva or if you take a sip of water, it

becomes sweet due to the presence of tannin. The presence of a large proportion of

tannins in the fruit may easily explain some of the more prosaic proclaimed benefits

of amla, including treatment of respiratory and intestinal disorders, particularly

intestinal ulcerations. In addition, polyphenols have been shown to have numerous

health protective benefits, including lowering blood lipids and blood sugar,

enhancing blood circulation, and blocking the action of carcinogens, which together

contribute to the antiaging effect. The apparent superior effect of the mistaken

"vitamin C" component is actually the more stable and potent anti-oxidant effect of

the tannins that appeared to be the vitaminC. Shibnath Ghosal [50], at the Banaras

Hindu University, published his findings about active constituents of emblica fruits

in 1996, reporting on the mistaken identification of vitamin C. He turned his research

13

findings into a patent just four years later; describing the production of the mixture

he called Capros. It is derived from amla by a careful process of extraction that

prevents breakdown of the tannins.

The first four ingredients listed are polyphenols (tannins); the next constituent

is a combination primarily of gallic acid and ellagic acid, the tannoid components

that are linked together to make the other tannins. Rutin is another phenolic

compound, a common flavonoid found in many plants and isolated as a natural

health care product. Dr. Ghosal describes his extract (U.S. patent # 6,124,268) as

having a greater antioxidant potential than vitamin C, while being more stable

against heat and oxidation. It can be formulated into skin creams that are designed to

protect the skin from damage due to excess sun exposure and may also be used as a

component of internal remedies for health protective effects, especially for

cardiovascular risk factors.

The health beneficial properties of amla make it wonderful natural products,

playing major role in Sidda, Ayurveda and natural medicine. It acts as key

ingredients in Amlaki Rasayanam, Ashokarista, Avipatikara churnam,

Chyavanaprasa leham, Dasamularistha, Dhatri lauha, Dhatryarista, Kumaryasava,

Panchatika guggulu ghritam, Triphala lepam, Triphala ghritam etc. This is an

attempt to explain about the phytochemistry and nutraceutical coumpounds of amla.

This is an attempt to describe the role of nutraceutical coumpounds of Amla on

human health.

Before, going in detail about the nutraceutical compounds of amla, it is

bound duty to explain about the definition for nutraceuticals. The term

“nutraceutical” is a hybrid or contraction of “nutrition” and “pharmaceutical”.

Reportedly, it was coined in 1989 by DeFelice and the Foundation for Innovation in

Medicine [51]. Restated and clarified in a press release in 1994, as “any substance

that may be considered a food or part of a food and provides medical or health

benefits, including the prevention and treatment of disease. Such products may range

from isolated nutrients, dietary, supplements and diets to genetically engineered

‘designer’ foods, herbal products, and processed foods such as cereals, soups and

beverages.”[52]. At present there are no universally accepted definitions for

14

nutraceuticals and functional foods, although commonality clearly exists between the

definitions offered by different health-oriented professional organizations. According

to the International Food Information Council (IFIC), functional foods are “foods or

dietary components that may provide a health benefit beyond basic nutrition.”[53]

The International Life Sciences Institute of North America (ILSI) has defined

functional foods as “foods that by virtue of physiologically active food components

provide health benefits beyond basic nutrition” [54]. Health Canada defines

functional foods as “similar in appearance to a conventional food, consumed as part

of the usual diet, with demonstrated physiological benefits, and/or to reduce the risk

of chronic disease beyond basic nutritional functions.” The Nutrition Business

Journal classified functional food as “food fortified with added or concentrated

ingredients to functional levels, which improves health or performance [55].

Functional foods include enriched cereals, breads, sport drinks, bars, fortified snack

foods, baby foods, prepared meals, and more.” As noted by the American Dietetics

Association in a position paper dedicated to functional foods, the term “functional”

implies that the food has some identified value leading to health benefits, including

reduced risk of disease, for the person consuming it [56]. One could easily argue that

functional foods include everything from natural foods, such as fruits and vegetables

endowed with antioxidants and fibre, to fortified and enriched foods, such as orange

juice with added calcium or additional carotenoids, to formulated ready-to-drink

beverages containing antioxidants and immune-supporting factors. The Nutrition

Business Journal states that it uses the term nutraceutical for anything that is

consumed primarily or particularly for health reasons. Based on that definition, a

functional food would be a kind of nutraceutical. On the other hand, Health Canada

states that nutraceuticals are a product that is “prepared from foods, but sold in the

form of pills or powders (potions), or in other medicinal forms not usually associated

with foods. A nutraceutical is demonstrated to have a physiological benefit or

provide protection against chronic disease” [55]. Based on this definition and how

functional foods are characterized, as noted previously, nutraceuticals would be

distinct from functional foods.

The potential functions of nutraceutical food ingredients are so often related

to the maintenance or improvement of health that it is necessary to distinguish

15

between a food ingredients that has function as a drug. The core definition of a drug

is any article that is “intended for use in the diagnosis, cure, mitigation, treatment, or

prevention of disease in man or other animals.”(21 U.S.C. 321(g) (1) (B)). At the

same time, certain health claims can be made for foods and ingredients that are

associated with health conditions. In the U.S., such health claims are defined and

regulated by the United States Food and Drug Administration (USFDA). Health

claims related to foods and ingredient include an implied or explicit statement about

the relationship of a food substance to a disease or health-related condition .

2.1.1 Phytochemistry of Amla

A wide range of plant species belonging to the genus Phyllanthus have

been phytochemically investigated. Among the studied species, P. niruri,

P. urinaria, P. emblica, P. flexuosus, P. amarus, and P. sellowianus have received

the most phytochemical and biological attention. According to the literature,

research has either been focused on isolating all the substances in these plants, or on

determining a specific class of natural products [49]. The P. emblica L. tree

contains the different classes of constituents listed in table 2.1 and references there

in.

2.1.2 Pyrogallol

Elena Nicolis [56] determined that the most relevant cause of morbidity and

mortality in cystic fibrosis (CF) patients is the lung pathology characterized by

chronic infection and inflammation sustained mainly by Pseudomonas aeruginosa

(P. aeruginosa). Innovative pharmacological approaches to control the excessive

inflammatory process in the lung of CF patients are thought to be beneficial to reduce

the extensive airway tissue damage. Medicinal plants from the so-called traditional

Asian medicine are attracting a growing interest because of their potential efficacy

and safety. Due to the presence of different active compounds in each plant extract,

understanding the effect of each component is important to pursue selective and

reproducible applications. Extracts from Emblica officinalis (EO) were tested in IB3-

1 CF bronchial epithelial cells exposed to the P. aeruginosa laboratory strain PAO1.

EO strongly inhibited the PAO1-dependent expression of the neutrophil chemokines

16

IL-8, GRO-α, GRO-γ, of the adhesion molecule ICAM-1 and of the pro-

inflammatory cytokine IL- 6. Pyrogallol, one of the compounds extracted from EO,

Table 2.1.1

The classes of chemical constituents of Phyllantus emblica L.

Class Compound Occurrence

Benzenoid

Chebulic acid Chebulinic acid Chebulagic acid

Leaves [57,58]

Gallic acid Leaves [57-59] Ellagic acid Leaves [57,60,61] ß-Glucogallin Leaves [58,62] Ellagic acid Fruit[63] Amlaic acid Corilagin 3-6-di-Ogalloyl-glucose Ethyl gallate

Fruit[58]

1,6-Di-O-galloyl-ß-Dglucose 1-Di-O-galloyl-ß-D glucose Putranjivain A Digallic acid Phyllemblic acid

Fruit[64-66]

Emblicol music (=galactaric) acid Gallic acid

Furanolactone Ascorbic acid Leaves [59] Fruit[67-69]

Flavonoid Leucodelphinidin Leaves[61] Kaempherol

Flavonoid

Kaempherol-3-glucoside Rutin Leaves[70] Quercetin Kaempherol-3-O-ß-Dglucoside Quercetin-3-O-ß-Dglucoside

Fruit[65]

Sterol ß-sitosterol Leaves[60]

inhibited the P. aeruginosa dependent expression of these pro-inflammatory genes

similarly to the whole EO extract, whereas a second compound purified from EO,

namely 5-hydroxy-isoquinoline, had no effect. These results identify Pyrogallol as an

active compound responsible for the anti inflammatory effect of EO and suggest to

17

extend the investigation in pre-clinical studies in airway animal models in vivo, to

test the efficacy and safety of this molecule in CF chronic lung inflammatory disease.

2.1.3 Cytotoxic effect

Jeena et al [71] found that the aqueous extract of Emblica officinalis (E.O)

was found to be cytotoxic to L 929 cells in culture in a dose dependent manner.

Concentration needed for 50% inhibition was found to be 16.5mg/ml. E.O and

chyavanaprash (a non-toxic herbal preparation containing 50% E.O) extracts were

found to reduce ascites and solid tumours in mice induced by DLA cells. Animals

treated with 1.25g/kg b.wt. of E.O extract increased life span of tumour bearing

animals (20%) while animals treated with 2.5g/kg b.wt. of chyavanaprash produced

60.9% increased in the life span. Both E.O and chyavanaprash significantly reduced

the solid tumours. Tumour volume of control animals on 30th day was 4.6ml whereas

animals treated with 1.25g/Kg b.wt. of E.O extract and 2.5g/kg b.wt. of

chyavanaprash showed a tumour volume of 1.75 and 0.75 ml, respectively. E.O

extract was found to inhibit cell cycle regulating enzymes cdc 25 phosphatase in a

dose dependent manner. Concentration needed for 50% inhibition of cdc 25

phosphatase was found to be 5mg/ml and that needed for inhibition of cdc2 kinase

was found to be 100mg/ml. The results suggest that antitumour activity of E.O

extract may partially be due to its interaction with cell cycle regulation.

2.1.4 Quercetin

Nagarajan Devipriya et al [72] investigated the radioprotective efficacy of

quercetin (QN), a naturally occurring flavonoid against gamma radiation-induced

damage in human peripheral blood lymphocytes and plasmid DNA. In plasmid study,

QN at different concentrations (3, 6, 12, 24 and 48M) were pre-incubated with

plasmid DNA for 1h followed by exposure of 6Gy radiations. Among all

concentrations of QN used, 24M showed optimum radio protective potential. To

establish the most effective protective concentration of QN in lymphocytes, the cells

were pre-incubated with 3, 6, 12, 24 and 48M of QN for 30min and then exposed to

4Gy radiation. The concentration-dependent effects of QN were evaluated by scoring

micronuclei (MN) frequencies. The results showed that QN decreased the MN

18

frequencies dose dependently, but the effect was more pronounced at 24M. Thus,

24M of QN was selected as the optimum concentration and was further used to

evaluate its radio protective effect in lymphocytes. For that a separate experiment

was carried out, in which lymphocytes were incubated with QN (24M) for 30min and

exposed to different doses of radiation (1, 2, 3 and 4Gy). Genetic damage (MN,

dicentric aberration and comet attributes) and biochemical changes were measured to

evaluate the effect of QN on radiations (1–4Gy). Radiation exposed cells showed

significant increases in the genetic damage and thiobarbituric acid reactive

substances (TBARS) accompanied by a significant decrease in the antioxidant status.

QN pretreatment significantly decreased the genetic damage and TBARS and

improved antioxidant status through its antioxidant potential. Altogether, our

findings encourage further mechanistic and in vivo studies to investigate radio

protective efficacy of QN

2.1.5 Gallic and ellagic acid

a. Gallic acid b. Ellagic acid

Figure 2.1.1 Structure of gallic and ellagic acid

The development of prostate cancer is accompanied by genetic alterations

that involve a diverse group of gene products including tumor suppressor genes,

oncogenes, cell cycle transcription factors, growth factors, DNA repair genes and

cell death regulators. Although multiple mechanisms appear to be responsible for the

19

tumor inhibitory properties of dietary polyphenols, information from earlier studies

[48-57] on the gene animaltic response to phytochemicals is very limited. Ellagic

acid (EA) has been shown [58-61] to inhibit tumor growth in animal assays with

chemical carcinogens such as poly cylic aromatic hydrocarbons, N-nitrosoamines,

aflatoxins and aromatic amines. EA and gallic acid (GA) are structurally different

shown in figure 2.1 but both are present in fruits such as grapes and berries at fairly

high levels. However, the similarity and the difference in the mechanism of action of

these two phenolic compounds in cancer cell are not fully understood. This begs the

question whether the cancer preventive potential is due to one agent specific

pharmacological effect or weather it represents a synergistic effect of both EA and

GA in modulating more than one mechanism. Our earlier observation [68,69]

indicated that ellagic acid inhibits cell proliferation. Thus would expect multiple

mechanistic pathways for EA to induce cell growth arrest and apoptosis.

Dr. Shibnath Ghosal, at the Banaras Hindu University, published his findings

about active constituents of emblica fruits in 1996, reporting on the mistaken

identification of vitamin C [50]. He turned his research findings into a patent just

four years later; describing the production of the mixture he called Capros. It is

derived from amla by a careful process of extraction that prevents breakdown of the

tannins. It contains the following substances.

• Emblicanin-A : 27%

• Emblicanin-B : 23%

• Punigluconin : 8%

• Pedunculagin : 14%

• Gallo-ellagitannoid : 18%

• Rutin : 10%

The structure of the major tannoid substances are shown in Figure 2.2. The

first four compounds listed are polyphenols (tannins); the next constituent is a

combination primarily of gallic acid and ellagic acid, the tannoid components that are

linked together to make the other tannins. Rutin is another phenolic compound, a

common flavonoid found in many plants and isolated as a natural health care

product. Dr.Ghosal describes his extract (U.S. patent # 6,124,268) as having a greater

20

antioxidant potential than vitamin C, while being more stable against heat and

oxidation. It can be formulated into skin creams that are designed to protect the skin

from damage due to excess sun exposure and may also be used as a component of

internal remedies for health protective effects, especially for cardiovascular risk

factors.

Figure 2.1.2 Major hydrolysable tannoids of Emblica officinalis.

Structures of the major tannoids of E. officinalis, emblicanin A (A), emblicanin B (B), punigluconin (C), and pedunculagin (D). While emblicanin A has one R1 and one R2 side groups, emblicanin B has two R2 side groups.

2.1.6 Health Benefits of Amla

According to Charaka the fruits are acrid, cooling, refrigerant and diuretic.

They are useful in hemorrhage, diarrhea and dysentery [73]. As per Jeena and

Kuttan findings amla fruits are anabolic, antibacterial and resistance building. They

21

possess expectorant, cardiotonic, antipyretic, antioxidative, antiviral and antiemetic

activities [74]. Kapoor reported that these fruits are used in the treatment of

leucorrhea and atherosclerosis. Amla is also used for the treatment of various gastric

ailments including dyspepsia [75].

Amla is highly nutritious and could be important dietary sources of Vitamin

C, minerals and amino acids. Zhang et al [76] reported that it also contains tannins,

phyllembelic acid, phyllemblin, rutin, curcuminoides and emblicol and phenolic

compounds. The pharmacological studies showed the ability of the fruits to lower

lipid levels in the liver of rabbits. In clinical study, Chawla et al [77] have found that

Amla was effective in gastric syndrome. The therapeutic efficacy of Amla in cases of

dyspepsia was evaluated by Chawla with promising results in human subjects.

Kalra and Singh observed that amla possess pronounced expectorant

antiviral, antibacterial, antioxidative activities. The known antioxidants, Gallic acid,

Catechol, Ellagic acid, Phloroglucinol, Pyrogallol, Trigalloylglucose, Indol acetic

acid (IAA), Vitamin C, beta-carotene, superoxide dismutase enzyme have been

reported to be present in the fruit [78,79]. According to Jain amla primarily contains

tannins, alkaloids, phenolic compounds, amino acids and carbohydrates. Its fruit

juice contains the highest vitamin C (478.56mg/100 ml). The fruit when blended

with other fruits boosted their nutritional quality in terms of vitamin C content.

Zhang also isolated certain compounds such as gallic acid, ellagic acid, 1-O-

galloyl-beta-D-glucose, 3,6-di-O-galloyl-Dglucose, chebulinic acid, quercetin,

chebulagic acid, corilagin, 1,6-di-O - galloyl beta D glucose, 3 Ethylgallic acid (3

ethoxy 4,5 dihydroxy benzoic acid) and isostrictin from amla [80]. According to

Habib-ur-Rehman et al EO also contains flavonoids, kaempferol 3 O alpha L (6''

methyl) rhamnopyranoside and kaempferol 3 O alpha L (6''ethyl) rhamnopyranoside

which act as anti-bacterial, anti-cancer, anti-epileptic, anti-inflammatory, anti-

oxidants, antispasmodic, anti-ulcer, gallbladder diuretics, relieve cough [81]. El-

Desouky et al isolated a new acylated apigenin glucoside (apigenin 7 O (6'' butyryl

beta glucopyranoside), cytotoxic compound from the methanolic extract of the leaves

of EO together with the known compounds; gallic acid, methyl gallate, 1,2,3,4,6-

penta-O-galloylglucose and luteolin-4'-Oneohesperiodoside [82].

22

2.1.7 Pharmacology and Clinical studies

Rao and Siddiqui [83] isolated Phyllembin from the ethanolic extract of the

fruit pulp which has been found to potentiate the action of adrenaline in vitro and in

vivo. It showed a mild depressant action on Central Nervous System and also had a

spasmolytic activity. The drug also revealed mild stimulant action on isolated frog

heart, short and insignificant rise in cat’s blood pressure, contraction of the

nictitating membrane, the reduction of outflow of the perfusate in the hind limb of

the rat and ear of rabbit, mild cerebral depressant action and anti-spasmodic activity.

In the indirect actions, it potentiate of the action of adrenaline on the blood pressure

of cat, isolated frog heart, and nictitating membrane of cat and the prolongation of

the hypnosis were also observed by them.

Further studies by Khurana et al on the action of phyllemblin revealed that

the drug antagonized the spasmogenic effect of acetylcholine, bradykinin and

serotonin on the guinea pig ileum. It also antagonized serotonin and acetylcholine-

induced contractions of oestrogenised rat uterus. It increased the amplitude of cardiac

contraction and heart rate transiently. An increase in coronary flow was followed by

persistent decrease. On perfused rat hind limb and rabbit ear preparation, phyllemblin

in small doses, increased the amount of perfusate whereas in larger doses it

decreased the flow significantly. A triphasic response that is initial transient rise,

followed by a transient fall and then sustained rise in blood pressure was seen in

anaesthetized albino rats. The sustained rise was blocked by phentolamine (1mg/kg.).

The drug produced 80 percent protection against leptazol seizures in mice. It

protected effectively against tremors and clonic and tonic convulsions induced by

nicotine. It also antagonized tremorine-induced tremors and other cholinergic

symptoms [84].

Khorana et al found that the ether extract and 80 percent alcoholic extract of

the fruits acidified with hydrochloric acid were showing antibacterial activity. The

other extract of acidified alcoholic extract showed the highest activity, inhibiting the

growth of M. pyogenes var. S. typhosa and S. paratyphi at a concentration of

0.21mg/ml and that of M. pyogenes var. albus; S. schottmmellari and S. dysenteriae

at a concentration of 0.42mg/ml [85].

23

Thakur and Mandal studied the effect of crude Amla (traditionally known as

amalaki rasayana) on total serum protein and its fractions in rabbits. The drug had no

significant effect on the levels of serum protein fractions, but it raised the total

protein level and increased the body weight. The studies indicated that the increase in

the body weight was due to positive nitrogen balance. The drug was found to have

only anabolic effect without affording resistance against diseases [86].

Clinical studies were conducted by Singh and Sharma to investigate the effect

of crude amla in gastritis syndrome. The crude Amla was given in 20 cases in a dose

of 3g, 3 times a day for 7 days. The drug was found effective in 85% of the cases. It

was observed that the drug did not have any significant beneficial effect in cases of

hypochlorhydria. Only cases of hyperchloridia with burning sensation in abdominal

and cardiac regions and epigastric pain were benefited [87].

Alcoholic extract of a plant (1g/kg) has shown an increase in the cardiac

glycogen and a decrease in serum GOT, GPT and LDH in isoprotenol pretreated rats,

suggesting a cardioprotective action. It showed a reduction in serum cholesterol

levels and a significant antiatherogenic effect. This study by Thakur and Caius

suggest that Vitamin C content alone may not responsible for the antiatherogenic

effect of the plant in animals [88].

The lipid lowering and antiatherosclerotic effects of amla fresh juice were

evaluated by Ritu Mathur et al [89] in cholesterol fed rabbits (rendered

hyperlipidemic by atherogenic diet and cholesterol feeding). Amla fresh juice was

administered at a dose of 5ml/kg body weight per rabbit per day for 60 days. Serum

cholesterol, Triglycerides, phospholipid and Low-density lipoprotein levels were

lowered by 82%, 66%, 77% and 90% respectively. Similarly, the tissue lipid level

showed a significant reduction following Amla juice administration. Aortic plaques

were regressed. Amla juice treated rabbits exerted more cholesterol and

phospholipids, suggesting that the mode of absorption be affected. Amla juice is an

effective hypolipidemic agent and can be used as a pharmaceutical tool in

hyperlipidemic subjects.

24

Rajarama Rao and Siddiqui also reported that amla have anti-cancer

properties by their clinical studies [83]. Roy et al reported that the crude extract of

Emblica officinalis counteracts hepatotoxic and renotoxic effects of metals due to its

antioxidant activity [90].

2.1.8 Uses of amla in Diabetes

According to Suryanarayan et al [91], oral administration of the extracts

(100mg/kg body weight) reduced the blood sugar level in normal and in alloxan

(120mg/kg) diabetic rats significantly within 4h. EO and an enriched fraction of its

tannoids are effective in delaying development of diabetic cataract in rats.

2.1.9 Applications of amla in Cancer

Triphala has been reported to exibit chemopreventive potential by Deep et al

[92]. The presence of Triphala in diet had significantly lowered the benzo(a)pyrene

[B(a)P] induced for stomach papillomagenesis in mice. It was more effective in

reducing tumor incidences compared to its individual constituents. Triphala also

significantly increased the antioxidant status of animals which might have

contributed to the chemoprevention.

2.1.10 Cardioprotective Activity of amla

Rajak et al investigated the effects of chronic oral administration of fresh

fruit homogenate of Amla on myocardial antioxidant system and oxidative stress

induced by ischemic-reperfusion injury (IRI) on heart in rats. Chronic EO

administration produces myocardial adaptation by augmenting endogenous

antioxidants and protects rat hearts from oxidative stress associated with IRI [93].

2.1.11 Amla and its Anti-ulcer Activities

A herbomineral formulation of the Ayurveda medicine named Pepticare,

composed of amla, Glycyrrhiza glabra and Tinospora cordifolia was tested by Bafna

and Balaraman for its anti-ulcer and anti-oxidant activity in rats [94]. Reports were

made that Pepticare exhibit anti-ulcer activity, which can be attributed to its anti-

oxidant property. Sairam et al studied the methanolic extract of EO (EOE) against

25

ulcer. EOE had significant ulcer protective and healing effects and this might be due

to its effects both on offensive and defensive mucosal factors [95].

2.1.12 Effects of amla on Liver

EO fruits have been reported to be used for hepatoprotection in Ayurveda by

Bhattacharya et al [96]. Phyllanthus emblica extract was investigated on ethanol

induced rat hepatic injury. Protective roles of this against ethanol induced liver injury

in rats are reported by Pramyothin et al [97].

2.1.13 Antioxidant Activities of amla

Yokozawa et al administrated of ethyl acetate extract of amla reduced the

elevated levels of urea nitrogen and serum creatinine in the aged rats. Oral

administration of this extract significantly reduced thiobarbituric acid-reactive

substance levels of serum, renal homogenate and mitochondria in aged rats,

suggesting that amla would ameliorate oxidative stress under aging. The increase of

inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 expression in

the aorta of aging rats were also significantly suppressed by EtOAc extract of Amla.

EtOAc extract of Amla reduced the COX-2 and iNOS expression levels by inhibiting

NF-kappaB activation in the aged rats. Thus amla would be a very useful antioxidant

for the prevention of age-related renal disease. According to Anilakumar et al., pre

feeding of amla appeared to reduce the hexachlorocyclohexane (HCH) -induced raise

in renal gamma-glutamyl transpeptidase (GGT) activity. This shows the elevation of

hepatic antioxidant system and lowering of cytotoxic products as which were

otherwise affected by the administration of HCH [98].

2.1.14 Active Roles of amla in Immunomodulation

Immune activation is an effective as well as protective approach against

emerging infectious diseases. Srikumar et al assessed the immunomodulatory

activities on Albino rats using Triphala on various neutrophil functions like

adherence, phagocytic index, avidity index and nitro blue tetrazolium. Oral

administration of Triphala appears to stimulate the neutrophil functions in the

26

immunized rats and stress induced suppression in the neutrophil functions were

significantly prevented by Triphala [99].

2.1.15 Antipyretic and Analgesic Activities of amla

According to Perianayagam et al extracts of EO fruits possess potent anti-

pyretic and analgesic activities. A single oral dose of ethanolic extract and aqueous

extract (500 mg/kg) showed significant reduction in hyperthermia in rats induced by

brewer's yeast. Both of these extracts elicited pronounced inhibitory effect on acetic

acid-induced writhing response in mice in the analgesic test . This may be due to the

presence of tannins, alkaloids, phenolic compounds, amino acids and carbohydrates

[100].

2.1.16 Cytoprotective, Antitussive, Gastroprotective Properties of amla

EO has been reported for its cytoprotective and immunomodulating

properties against chromium (VI) induced oxidative damage. According to Sai et al it

inhibited chromium induced immunosuppression and restored gamma-IFN

production by macrophages and phagocytosis [101].

Nosál'ová et al tested EO for its antitussive activity in conscious cats by

mechanical stimulation of the laryngopharyngeal and tracheobronchial mucous areas

of airways. Antitussive activity of EO was more effective than the non-narcotic

antitussive agent dropropizine but less effective than shown by the classical narcotic

antitussive drug codeine. It is supposed that the dry extract of EO exhibit the

antitussive activity not only due to antiphlogistic, antispasmolytic and antioxidant

efficacy effects, but also to its effect on mucus secretion in the airways [102].

Al Rehaily et al investigated EO (ethanolic extract) for its antisecretory and

antiulcer activities using various experimental models in rats, including pylorus

ligation Shay rats, indomethacin and hypothermic restraint stress induced gastric

ulcer and necrotizing agents. It was then reported that amla extract exhibit

antisecretory, cytoprotective and antiulcer properties [103].

27

2.1.17 Roles of amla in Reducing Cholesterol and Dyslipidemia

Cu(2+)-induced LDL oxidation and cholesterol-fed rats were used to

investigate by Kim et al [104] to study the effects of amla on low-density lipoprotein

(LDL) oxidation and cholesterol levels in vitro and in vivo. It was concluded that

amla may be effective for hypercholesterolemia and prevention of atherosclerosis.

According to Anila, L. and N.R. Vijayalakshmi EO and Mangifera indica contains

flavonoids which reduce the levels of lipid in serum and tissues of rats induced

hyperlipidemia. Both cause the degradation and elimination of cholesterol [105].

2.1.18 Memory Enhancing Effects of amla

According to Vasudevan and Parle amla churna produced a dose-dependent

improvement in memory of young and aged rats. It reversed the amnesia induced by

scopolamine and diazepam. Amla churna may prove to be a useful remedy for the

management of Alzheimer's disease due to its multifarious beneficial effects such as

memory improvement and reversal of memory deficits [106].

2.2 AMLA BASED PRODUCTS

Under this broad heading amla based products and their changes in

nutritional qualities on processing and storage were explained. Ranges of products

were developed from amla in different categories like food, siddha and ayurvedic

products. There is more number of dried, dehydrated and osmotically dehydrated

products from amla as well as the residue incorporated bakery product were also

developed from it. Also some of the important ayurvedic and siddha products from

amla were discussed here.

2.2.1 Amla murabba

In India, preserves or murrabbas of various kinds are used for taste as well as

for medicinal purpose. It is acclaimed to impart energy to heart, brain and liver. It is

also reported to stop diarrhea and useful as remedy for giddiness [107]. The preserve

of banarasi amla cultivar treated with salt and alum proved to be superior regarding

the maximum TSS, ascorbic acid, reducing sugar, total sugar and considerable

acidity and it can be stored at room temperature for five months [108]. The effect of

28

sugar concentration at different temperature on the kinetics of total sugar gain,

moisture loss, ascorbic acid loss, TSS gain in amla preserve was studied by Geetha

et al [109].

2.2.2 Amla-candy

Tandon et al [110] studied the effect of blanching and lye peeling on candy

preparation. They found that the candy prepared from lye peeled fruits of Amla

showed decreased content of ascorbic acid than blanched fruits. The candy prepared

from Lakshmi-52, Kanchan and Chakaiya was found to be the best.

Agrawal and Chopra [111] have carried out a study with regard to changes

occurring in ascorbic acid and total phenols during storage in different amla

products. They observed that the shreds registered greater loss in ascorbic acid

followed by jam, candy and squash. However, the candy showed greater loss in total

phenols followed by shreds and squashes and jams recorded slight increase in total

phenol content. On the whole, squash contained highest percentage of ascorbic acid

and total phenols.

2.2.3 Amla shreds and Amla flakes

A study carried out by Pragati et al [112] on amla fruit drying by 4 different

methods viz., osmo-air drying, direct sun drying, indirect solar drying and oven

drying. They observed that the osmo-air drying method was best for the drying of

amla fruits, resulting in better retention of nutrition, such as ascorbic acid, sugars and

less acidity. They also found that the level of anti-nutrition, such as tannins were also

lower in osmo-air dried amla, because the leaching and the browning were minimal.

The nutrition content in osmo-air dried amla was satisfactory after 90 days of

storage.

The best quality amla shreds were obtained with 0.1% KMS blanching and

drying in solar dryer with added common salt at 3%. The most acceptable product

had ascorbic acid content 298.3mg/100g, tannin 2.4%, acidity 2.6%, reducing sugar

3.0%, non-reducing sugar 21.0% and total sugar 24.0%. The recovery was 8.0–8.5%

[113].

29

Ready-to-eat dried amla shreds are prepared by blanching whole amla fruit in

boiling water for 10min, cooled and the segments are separated. Shreds were

pretreated with 70°Brix hot sugar solution at 85°C for 5min and soaked overnight in

the same solution. Then shreds were drained and dried in a cabinet drier at 58–60°C

to a moisture level of 5percentage. Amla shreds were packaged in HDPE and stored

at room temperature for 4 months [114].

Sweet amla flakes of high consumer acceptability is produced at 60° brix,

72min process time, 60°C temperature at solution to fruit ratio 6:8.The osmotically

dehydrated to safe moisture level and stored in LDPE bags [115].

2.2.4 Dried Amla fruit

Osmotic dehydration of whole pricked Amla fruit was carried out in brine

solution at 22% salt concentration, 44.5°C temperature, 6.5v/w solution to fruit ratio,

and 60min process duration. The fruit retained 75.03% of vitamin C with minimum

colour change, solute gain and maximum water loss. The osmotically dehydrated

fruit is dried in hot air oven till 10%. The dried product is stored in LDPE bags for

storage studies [115]. Drying is an effective method to increase shelf life of amla

fruits. Dried fruits are useful in chronic dysentery, diarrhea, diabetes, dyspepsia,

cough, anemia and jaundice [116].

Varma and Gupta [117] conducted a study on solar dried amla and reported

that flaking pretreatment followed by solar drying retained more ascorbic acid when

compared to pricking and blanching. The greater retention of ascorbic acid in flaking

treated amla might be due to reduced exposure of the sample in the drying air, which

prevented its loss. The pretreatments like blanching, flaking, pricking, sulphitation

followed by solar drying significantly improved the retention of ascorbic acid, color,

texture, appearance, taste, flavour and over all acceptability of the amla compared to

the control sample. Kavitha et al [118] studied the effect of osmotic dehydration on

vitamin C content of amla at different salt concentrations and different temperatures.

The overall retention of vitamin C was found better in the un-blanched osmotically

dehydrated and aired dried samples.

30

2.2.5 Amla powder

Spray dried amla powder was developed at pressure of 2.4x102 kPa with inlet

temperatures 120 and 160°C and the outlet temperature 80°C. The feed rate for the

spray dryer was set to 1.2ml/min. The powder obtained at 120°C have relatively

more vitamin C, with less water activity considered to be stable for microbial

growth. The powder stored in air tight HDPE kept at cool temperatures has no

changes in water activity for one month, however the powder stored in LDPE bags

has more shelf life [119].

The fruits of Chakiya variety were used to prepare the powder by different

techniques like freeze drying, sun drying, spray drying, hot air drying and vacuum

drying. Powder yield was more by vacuum drying followed by solar dying, tunnel

drying, spray drying and freeze drying. The freeze dried powder had the highest

ascorbic acid content followed by spray dried powder. The lowest concentration of

ascorbic acid was found in sun dried powder. Freeze dried samples showed

maximum mineral contents in terms of calcium, phosphorus and iron [120].

2.2.6 Amla pomace incorporated biscuits

Dietary fibre, vitamin C and antioxidant-enriched biscuits have been

developed by incorporation of amla pomace (a byproduct generated during Amla

juice processing). The dietary fibre content of the finished product was about 5-fold

higher than the control and the vitamin C and antioxidant concentration were

15.6mg/100g and 0.25g percentage respectively. Biscuits have a shelf-life of more

than 3 months when wrapped in 100 gauge polypropylene pouches under ambient

conditions. The biscuits can be supplemented as fibre, vitamin C and antioxidant

fortified diet for children and adult alike. The fibre-enriched biscuits may be helpful

in curing the constipation and other ailments related to fast food habits [121].

2.2.7 Amla mouth freshener

Nutritive and palatable mouth fresheners which are substitute for pan masala,

tobacco and gutka are prepared from ‘Desi’ and ‘Banarsi’ cultivars by mixing

carboxy methyl cellulose, gums, areca nut, cardamom, sugar and milk powder at

31

different proportions on the basis of overall sensory acceptability irrespective of

cultivars. Mouth fresheners developed were packed in HDPE bags and stored at

ambient condition for 6 months. The moisture content of the mouth freshener

increased during storage and ascorbic acid decreased during storage irrespective of

the cultivar [122].

2.2.8 Amla juice

Anup et al [123] carried out a study to detect the changes in color and quality

attributes of Amla juice during storage after. After extracting juice from Amla cv.

Chakaiya, it was pasteurized (at 75, 80, 90 and 95°C) and preserved with 500ppm

sulphur dioxide in PET bottles under ambient conditions for 9 months. The ascorbic

acid and polyphenols in juice decreased with increase in storage period but gallic

acid content in juice decreased initially but increased sharply as the storage period

prolonged high. High degree of non-enzymatic browning was observed throughout

the storage period, though least browning was observed in juice pasteurized at 75°C,

but microbial growth was observed after 9 months of storage. Hence, pasteurization

temperature of 80°C was found optimum for preservation of amla juice under

ambient conditions.

Nath [124] carried out a study on the extraction of Amla pulp and suggested a

method for preparation of amla pulp from fully matured fruits. In this process, the

fruits are blanched in boiling water for about 10min to separate the segments from

stone. Equal quantity of water was added to the segments and in the pulper to make

pulp. If the pulp has to be preserved, it should be pasteurized at 75°C and cooled to

room temperature. Potassium metabisulphite (2g/kg of pulp) should be mixed

thoroughly and the pulp should be filled in clean sterilized bottles and then sealed.

2.2.9 Amla supari

Amla supari was produced by osmotic dehydration of Amla in the brine

solution containing fresh ginger extract, dry ginger power, cumin powder and

fenugreek powder. The osmotic dehydration was done for 24h. The osmotically

dehydrated product was dried further in a tray drier [125].

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2.2.10 Amla squash

De seeded fruits were cut into small pieces. Fruit pieces were crushed with

equal quantity of water, filtered and added 1.86kg to each liter of extracts. Added

30g citric acid and 10g potassium meta bisulphate per kg of fruits, heated for some

time. Then the flavour/colour 100ppm was added, poured into bottles and sealed

[124].

2.2.11 Amla blended sauce

Chauhan et al [126] carried out study to prepare sauce by using amla pulp

blended with tomato pulp. Amla pulp was blended in 50:50 ratio and sauce was

prepared by optimizing the ingredients for it. The amla, tomato and the Sauce

prepared by their blend 50:50 were analyzed by physiochemical characteristics. The

sauce was stored in presterilized glass jar at room temperature for 90 days. The

sensory score for color, appearance, flavor, texture and over all acceptability are

found in acceptable limits upto 90 days storage.

2.2.12 Amla pickles

Commercially amla pickles were made by cutting fruits into 4-6 vertical

pieces and removed seeds followed by addition of 150g salts per kg fruit and keeping

it overnight and blanching of the fruits. Grind spices and ingredients such as 10g

turmeric powder, 20g mustard seeds, 30g chilies, 40g fenugreek seeds were added

for taste. They were mixed and kept overnight followed by addition of 200ml heated

oil per kgs of fruits. The pickles were poured into jars or pouched and sealed [124].

2.2.13 Amla based Siddha products

There are more than 200 formulations of amla described by Nadkarni [127].

These formulations are used in a wide range of disorders like conjunctivitis, vision

disorder, hyperacidity, rheumatic disorder, abdominal disorders, jaundice, hiccough,

breathing disorders, fever, cough, ear disorder, skin disorder, intoxication due to

alcohol etc. These are Amlaki Rasayanam, Ashokarista, Avipatikara churnam,

Chyavanaprasa leham, Dasamularistha, Dhatri lauha, Dhatryarista, Kumaryasava,

Panchatika guggulu ghritam, Triphala lepam, Triphala ghritam etc.

33

2.3 AMLA PIECES

The previous broad topic revealed range of dried and dehydrated produces

developed from amla. Under this heading a specific technique was selected for

discussion. This part will be used for planning and execution of osmotic dehydration

process for amla pieces with spices. Here, the general composition of amla, basic

concept of osmotic dehydration (OD) process, changes in the nutritional parameters

during OD as well as other post harvest technologies available for amla will be given

priority for detailed discussions.

2.3.1 General composition of Amla

The chemical composition of Amla fruits is influenced by environmental

factors. The chemical composition of the Amla fruit is different in different varieties.

The fresh fruits of amla of chakaiya variety are very rich source of ascorbic acid

(454.40mg/100g) and appreciable source of total sugar (7.53mg/100g), calcium

(14.91mg/100g), Iron (0.62 mg/100g) and phosphorus (11.81mg/100g) [128]. The

banarasi variety of amla has the moisture content 84.36%, pH 2.5, acidity 2.24%,

ascorbic acid 571mg/100g, total sugars 3.11%, tannins 0.55% and proteins 0.88%.

The fruits are rich in ascorbic acid and tannins [129]. Kalra [25] reported that the

total sugars content in Amla fruit varies from 7 to 9.6%, reducing sugars from 1.04 -

4.09% and non-reducing sugars from 3.05 - 7.23% among the various varieties. Amla

is particularly rich in vitamin C. The pulp of fresh fruit contains 200-900mg/100g of

vitamin C as reported by several workers.

The fruits have 28% of the total tannins distributed in the whole plant.

Several active tannoid principles (Emblicannin A, Emblicannin B, Punigluconin and

Pedunculagin) have been identified which appear to account for its health benefits

[130,131]. The two hydrolysable tannins Emblicannin A and B, one on hydrolysis

gives gallic acid, ellagic acid and glucose wherein the other gives ellagic acid and

glucose. The fruit also contains Phyllemblin [132-134]. The leaves and barks of

Amla tree are also rich in tannins. The root contains ellagic acid and lupeol and bark

contains leucodelphinidin. The seeds yield a fixed oil (16%) which is brownish-

34

yellow in color. It has the following fatty acids: linolenic (8.8%), linoleic (44.0%),

oleic (28.4%), stearic (2.15%), palmitic (3.0%) and myristic (1.0%) [135].

2.3.2 Osmotic dehydration of fruits and vegetables

Osmotic dehydration is a water removal process, involving soaking foods,

mostly fruits and vegetables, in a hypertonic solution such as concentrated sugar

syrup or brine. Two major simultaneous counter-current flows occur during osmotic

dehydration; Water flows out of the food into the solution and a simultaneous

transfer of solute from the solution into the food [31]. There is also a third flow of

natural solutes such as sugars, organic acids, mineral, salts, leaking from the food

into the solution. All these mass exchanges may have an effect on the organoleptic

and nutritional quality of the dehydrated product. It works well as a pre-treatment

prior to drying by other methods.

Some aspects of osmotically dehydrated fruits have been reviewed by various

workers with reference to osmotic agents and their concentration [136], temperature

[137], sample to solution ratio [138], agitation of fruit in syrup [139], sample size

and shapes [140], osmotic agents [141], material type [142], pre-treatment [143],

temperature and concentration [144], dehydration method and physico-chemical

changes. Some of the commonly used osmotic agents are sucrose, fructose-

oligosaccharide, sorbitol, galactosylosorbitol, oligofructose, inverted sugar [145], salt

etc.

Some of the osmotically dehydrated fruits and vegetables are sour cherries,

black current, apple [145], pineapple [146], banana [147], tomato halves [148],

whole amla fruit [115], carrot [149], radish [150], papaya [151], diced green peppers

[152] etc. As mentioned above there were many amla products, the present

experiment is conducted to study the effect of incorporate spices in to the amla slices

so that the consumer acceptability is increased. Moreover the shelf life of the product

can be increased as the spices (ginger, cumin and fenugreek) have anti microbial

activity.

35

2.3.3 Changes in the quality of Amla fruit during processing

2.3.3.1 Acidity

Amla fruits are not consumed in fresh form because of its acidic 2.5% [121]

and bitter taste. It is, therefore, not popular as a table fruit so there is a need for the

development of the value added amla products [107]. The titrable acidity of the amla

fruit can be reduced by hot water and potassium metabisulphite blanching [115]. The

acidity in the pulp of raw amla fruit pulp is high when compared to blanched fruit

[28]. The decrease in acidity after blanching is due to the heavy leaching losses of

acids during blanching the amla fruit slices [153].

Drying the amla slices also reduces acidity due to the conversion of acids in

to sugars or some other compounds or acids might have been utilized in process of

respiration. The acidity of the fruit can also reduced by treating it with common salt,

black salt and ginger. The combined effect of blanching, treating the fruit (with salt

and ginger extract) and drying has significant effect on acidity [115]. Osmotic

dehydration followed by drying the amla fruit significantly reduces acidity due to the

leaching out of acids during osmosis but there is a significant increase in the titrable

acidity of the osmo dried amla fruit during the storage for 60 to 90 days [114].

In general, total acidity of dehydrated amla fruits increased significantly

during storage. Similar findings have been reported in Desi and Banarasi cultivars of

amla [154]. Acidity values increased gradually with storage time in an intermediate

amla preserve. Similar trends have also been observed in dates [155]. This increase

in acidity might have been due to formation of acids due to inter-conversion of

sugars and other chemical reactions [156] which were accelerated at high ambient

temperature [157]. Also, de esterification of pectin molecules occurs during storage

resulting in the loss of jelly grade which leads to a gradual decrease in methoxyl

content and increase in titrable acidity [158,159]. On the contrary, a decrease in

acidity level in dehydrated amla during storage has also been reported by several

workers [160,130]. The acidity of the amla preserves (Murabba) reduces during

storage [108].

36

2.3.3.2 Ascorbic acid

Amla fruit is highly nutritive with a great medicinal use and the richest source

of vitamin C. It contains 500-1500mg of ascorbic acid per 100g of pulp [126]. This is

much more than the vitamin C content of guava, citrus and tomato fruits. The

ascorbic acid content of fresh amla fruit can range up to 950mg/100g which is said to

highest among all fruits next only to Barbados cherry [9]. Ascorbic acid shows

antioxidant, anti-inflammatory and antimutagenic properties [9,12]. It is a very

effective free-radical scavenger.

Vitamin C is sensitive to heat and oxidative degradation. Blanching the amla

pieces for 3min in boiling water or blanching with 0.1% KMS for 3min do not have

significant effect on ascorbic acid. The higher amount of ascorbic acid was retained

in amla pieces when blanched with KMS [115]. Beneficial effect of blanching with

KMS or sulphitation on retention of ascorbic acid content of dried amla product was

also observed by many workers [28,115,130]. It may be due to inactivation of

oxidase enzyme. The vitamins in sulphured fruits were preserved but not in

unsulphured ones during storage [161]. It was observed that during the production of

dried amla shreds, addition of black salt and ginger juices to the blanched amla

pieces (hot water and KMS blanched) helped in retaining ascorbic acid.

The osmotic dehydration of amla in brine solution or in sugar syrup resulted

in the loss of ascorbic acid. The loss in ascorbic acid during the osmotic dehydration

is more in amla pieces when compared to the whole amla fruit [117]. This is due to

the movement of solutes such as sugars, organic acids, mineral and salts leaching out

from the food into the solution [31].

The ascorbic acid content of dried amla product is significantly affected by

drying methods. The loss in vitamin C content during drying involves oxidation and

hydrolysis. The ascorbic acid is oxidised to dehydroascorbic acid, followed by

hydrolysis to 2, 3-diketogulonic acid and further oxidation and polymerisation to

form a wide range of other nutritionally inactive products (Gregory III, 2008). The

indirect solar drying method was comparatively better than direct solar drying in

terms of nutritional value of dried amla fruit [113]. But the solar drier proved better

37

for retention of ascorbic acid than sun drying in dried amla [162,163,113] reported

that osmo-air dried amla retained more amount of ascorbic acid followed by oven

dried, direct solar dried and indirect solar dried but the reduction of ascorbic acid

during storage was highest in osmo-air dried fruit followed by oven dried and then

direct and indirect solar dried amla [113]. Alam et al [163] has reported 30% loss of

ascorbic acid during sun drying of fresh amla pulp. They also studied drying of amla,

chakaiya and banarsi in mechanical dryer at 60°C after pre-treatment with blanching

and sulphitation and compared with sun dried samples. They found the pre-treated

and mechanically dried chakaiya variety of amla to the quality attributes after drying.

Varma and Gupta reported that 64% of ascorbic acid was retained in sliced amla

sample dried in open sun. The amla slices retained high amount of ascorbic acid

when dried in fluidized bed drier when compared to those dried under sun and hot air

oven dryer [164]. The retention of vitamin C in freeze-dried products is significantly

higher than that of oven and sun-dried products. Microwave and vacuum drying

methods can also reduce the loss of ascorbic acid due to low levels of oxygen.

Microwave, Refractance window, low pressure superheated steam and vacuum

drying can also reduce the loss of vitamin C due to a low level of oxygen. But, shade

drying, in the absence of light, can also be effective for the retention of nutrients

[165]. Ascorbic acid content of dehydrated amla decreased further when stored for 3

months [113]. There is a loss of ascorbic acid content in amla preserve during

storage; this loss is less in the initial stages of storage [166,167].

2.3.3.3 Tannins

The fruits have 28% of the total tannins distributed in the whole plant. Amla

fruit contain 0.55% tannins in it [130]. Apart from ascorbic acid ascorbic low

molecular hydrolyzable tannins emblicanins A and B have been suggested to be the

contributory antioxidant in amla [168]. Sethi [28] reported higher retention of tannin

in unblanched dried fruit of amla than blanched fruits. Losses of tannin during

blanching have been reported by Pant et al [153]. Blanching with hot water retained

significantly higher tannin content when compared to KMS blanching [113].

Vijayanand et al [169] have reported tannin content in amla powder is more when

whole fruit was blanched. It suggests that loss of tannin is more when blanching is

38

done after making shreds. The tannins content in osmo-air dried amla is less

compared to oven dried; solar dried and indirect solar dried amla might have been

due to leaching of tannins during osmosis [114]. The total tannin contents of dried

amla decreased significantly during storage. This decrease in total tannins in dried

amla might have been due to the action of the enzyme polyphenoloxidase which

might have converted tannins into other products [160]. Significant reduction in

tannin content has also been reported in bael preserve [170] and in processed sand

pear products during storage [171].

2.3.3.4 Total sugars

Kalra [55] reported that the total sugars content in amla fruit varies from 7 to

9.6%, reducing sugars from 1.04 to 4.09% and non-reducing sugars from 3.05 to

7.23% among the various varieties. Sethi [28] reported higher retention of sugars in

unblanched amla fruit compared to blanched fruit. Pragati et al [112] reported heavy

leaching losses in sugars during blanching and sulphitation of amla. Blanching with

hot water retained significantly higher total sugar content compared to KMS

blanching. Blanching significantly affected the total sugar content of dried amla

product. The total sugar content of amla is affected by drying treatments. It was

found that the total sugar content of osmo-air dried amla was significantly higher

followed by indirect solar dried, oven dried and solar dried amla due to absorption of

sugars during osmosis. A significant increase in total sugar content of blueberries

[172], was reported when the fruits were osmo air dried. During the storage period of

dried amla for 3 months there is a significant decrease in total sugars. The decrease

in total sugars might be due to the non-specific hydrolysis of macromolecules,

interconversions of sugars and aggregation of monomers during storage [173,174].

There is a marked increase in total sugar content of amla preserve (Murabba) during

storage period [108].

2.3.3.5 Reducing sugars and non reducing sugars

Kalra [78] reported that the reducing sugars content in amla fruit varies from

1.04 to 4.09% and non-reducing sugars from 3.05 to 7.23% among the various

varieties. Blanching has significant effect on reducing sugars and non reducing

39

sugars. Hot water blanching retained higher amounts of reducing and non reducing

sugars. Drying significantly affected reducing and non reducing sugars. The reducing

sugar content was found to be highest in osmo-dried amla followed by indirect sun

dried amla and oven dried amla [113]. During storage, the reducing sugar content of

dried amla decreased significantly this might be due to the dehydration reactions

causing sugars to become unsaturated and highly reactive; the hexose reducing

sugars are partially converted to 2-furaldehyde and 5-hydroxymethyl-2-furaldehyde

[175], which might remain undetected in a reducing sugar test. A decrease in

reducing sugars during storage in dried amla of Desi and Banarasi cultivars has been

reported [153]. There is a marked increase in reducing and total sugar content of

amla preserve (Murabba) during storage period [108].

2.3.3.6 Browning

Browning occurs in amla pieces when they are subjected to high

temperatures. Browing is maximum in solar dried amla pieces when compared to

osmo-dried amla. The browning in indirect solar dried amla was significantly lower

than that in direct solar dried amla was possibly due to the photo-oxidation of

carotenoids after long exposure to light and oxygen [113]. Lower browning in

blanched and osmo-dried ber has been reported by Flink [176] because concentrated

osmotic solution has been reported to be best for reducing browning as it prevents

the entrance of oxygen. Discolouration of ascorbic acid containing vegetables can

occur due to formation of dehydroascorbic acid and diketogluconic acids from

ascorbic acid during the final stages of drying. Sulphur treatment can prevent this

browning due to reactivity of bisulphite towards carbonyl groups present in the

breakdown products [177]. Browning of dried/dehydrated amla just after drying was

lowest but increased significantly during storage. The increase in browning might be

due to a wide range of residual peroxidases, polyphenoloxidases and lipooxigenases

even after blanching, as in green peas [178]. Decline in ascorbic acid content may

also been the possible reason for development of browning [179].

40

2.3.4 Post harvest technology of Amla

Amla fruit is underutilized in India even though it is a low cost important fruit

valued for its nutritional and medicinal properties and it is one of the main sources of

livelihood for the poor and play an important role in overcoming the problem of

malnutrition. Amla fruits can grow under adverse conditions and are also known for

its therapeutic and nutritive value and can satisfy the demands of the health-

conscious consumers [180]. Amla fruits are highly perishable in nature as it`s storage

in atmospheric conditions after harvesting is very limited. Due to its perishable

nature, it is difficult to store or transport amla fruits for long distances. In order to

have good income from amla, it must be sold immediately in the market. But, the

problem arises when there is glut in the market. Amla fruits are not consumed in

fresh form because of its acidic and bitter taste. It is, therefore, not popular as a table

fruit. However, excellent nutritive and therapeutic values of the fruit have great

potentiality for processing into several quality products. As amla is a perishable, the

fruit needs processing to increase shelf-life and value addition; particularly during

glut period. Processing not only reduces the post harvest losses but also provides

higher returns to the growers [107].

Amla has been in use for pickle and preserve since ages in India. It has been

an important ingredient for chavanprash, an ayurvedic health tonic and triphala

churnam, a herbal formulation used extensively in siddha system of Indian medicine,

treating wounds and local ulcers. The traditional methods of processing amla are

time consuming and the prepared product has less shelf life. The modern methods for

preparation of different amla products are hygienic, consume lesser time and provide

maximum retention of nutrients. The processes for preparation are standardized with

proper preservation.

2.4 AMLA RESIDUE INCORPORATED BREAD

Amla residue incorporated bread is the second product developed in this

work. Here, the functional properties of dietary fibre are briefed along with the

definition for functional foods. The basic concepts on bread making as well as

impact of dietary fibre on bread is discussed in detail. The physiological functions of

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dietary fibre on colon health, heart disease, obesity, diabetics, diverticulosis and

constipation are discussed in detail along with other functions of it. Recommended

dietary allowances for dietary fibre by many organizations and professional bodies

are described in detail.

2.4.1 Functional Food

A relatively recent concept in the U.S. to describe the broad healthfulness of

foods is the term “functional foods.” These foods are defined as foods that provide

health benefits beyond basic nutrition. The Food and Nutrition Board of the National

Academy of Sciences described a functional food as, “any modified food or food

ingredient that may provide a health benefit beyond that of the traditional nutrients it

contains” [181].

According to Wildman the emergence of dietary compounds with health

benefits offers an excellent opportunity to improve public health and thus, this

category of compounds has received much attention in recent years from the

scientific community, consumers and food manufacturers. The list of dietary active

compounds (vitamins, probiotics, bioactive peptides, antioxidants etc.) is endless,

and scientific evidence to support the concept of health promoting food ingredients is

growing steadily [182].

The term “Functional Foods” was first introduced in Japan in the mid-1980s

and refers to processed foods containing ingredients that aid specific body functions,

in addition to being nutritious. Currently, there is no universally accepted term for

functional foods. A variety of terms have appeared world-wide such as

nutraceuticals, medifoods, vitafoods and the more traditional dietary supplements

and fortified foods. However, the term Functional foods has become the predominant

one even though several organizations have attempted to differentiate this emerging

food category. Health Canada, for instance, defines a functional food as “similar in

appearance to a conventional food, consumed as part of the usual diet, with

demonstrated physiological benefits, and/or to reduce the risk of chronic disease

beyond basic nutritional functions” and a nutraceutical as “a product isolated or

purified from foods that is generally sold in medicinal forms not usually associated

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with foods (Health Canada website: http://hc-sc.gc.ca). According to Kim in Korea,

functional foods are defined as dietary supplement whose purpose is to supplement

the normal diet and have to be marketed in measured doses, such as in pill, tablets

[183].

According to the traditional concept of nutrition, the primary role of the diet

is to provide adequate quantities of nutrients to meet metabolic requirments and

maintain optimal health. However according to Takachi epidemiological,

experimental and clinical studies have shown that certains types of food and specific

food components can affect a variety of body functions and provide health benefits.

Based on scientific data it is now accepted that diet can have beneficial physiological

effects, beyond well-known nutritional effects, by modulating specific target function

in the body. Therefore, diet not only helps to achieve optimal development and

health, but it may promote better health and play an important role in disease

prevention by reducing the risk of certain chronic diseases [184].

Currently, Food and Drug Administration (FDA) has neither a definition nor

a specific regulatory rubric for foods being marked as “functional foods”, they

are regulated under the same regulatory framework as other conventional

foods under the authority of the Federal Food Drug and Cosmetic Act (FFDCA)

Source (http://www.cfsan.fda.gov/~dms/hclaims.html).

2.4.2 Bread

Bread is one of the most important bakery products which consist of two

distinctly different parts named as crust and crumb. While the crust is the dry and

crispy surface layer of the bread, the crumb is the soft part under the outer surface. It

is important to produce a soft and fine crumb and this is achieved by dough mixing

with formation of proper gluten network. There are lots of different varieties of bread

that differ in shape, size, texture, color, and flavor. The ingredients can vary or the

baking conditions may differ from bread to bread [185]. Flour, water, leavening

agent (yeast or chemicals) and sodium chloride are the basic ingredients that form the

bread dough. According to Mondal and Datta [186] flour and water are the

substances that affect the texture and crumb the most, they are the most crucial

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ingredients in a bread recipe. In a recipe flour is always 100% and the rest of the

ingredients are a percent of that amount by weight.

Scanlon and Zghal [42] described that three main objectives are sought in the

processing operations of bread. The first operation is the mixing and dough

development (mixing and fermenting); then foam structure formation in the dough

(moulding, proofing and baking) follows; and finally porous structure stabilization

by the help of heat (baking) comes.

According to Faridi and Faubion dough is the intermediate stage between

flour and the bakery product. The rheological characteristics of the dough are very

important, as they influence the machinability of the dough as well as the quality of

the finished product [187]. These characteristics depend on several factors such as

ingredient quality and quantity, mixing conditions, resting time and temperature of

the wheat flour dough [188]. In recent years the interest for high fibre content in

foods has greatly increased and brown flours or high extraction flours are being used.

2.4.3 Dietary Fibre and its effect on body

Dietary fibre is an important part of a health promoting diet. According to

Southon basically the term dietary fibre refers to some complex carbohydrates and

lignin found in plants, which are undigested by human alimentary tract enzymes

[189]. Goldman et al explained that although dietary fibre is not digested in the small

intestine, and absorbed into the body, it is linked with healthful diet because of its

protective role against many chronic diseases [190].

Of particular interest to the research community at the moment is the

possibility of using dietary fibre-based interventions or therapies as a means of

reducing risk of cardiovascular disease, type II diabetes and combating obesity.

According to Hu et al strong observational evidence exists to suggest that

populations who consume higher levels of dietary fibre have a significantly reduced

risk of morbidity and mortality from the above conditions [191].

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According to Spiller Dietary fibre (DF) plays an important role in decreasing

the risks of many disorders such as constipation, diabetes, cardiovascular diseases

(CVD), diverticulosis and obesity [192].

Selvendran and MacDougall explained that Plant foods are the only sources

of DF. All the fractions (cellulose, lignin, hemicellulose, pectins, gums and

mucilages) of DF are the major constituents of plant cell wall [193].

Dietary fibre is subdivided into Insoluble Dietary Fibre (IDF) and Soluble

Dietary Fibre (SDF) depending on their solubility in water. However, according to

Roberfroid the DF can be grouped into two major types (a)

soluble/viscous/fermentable and (b) insoluble/nonviscous/slowly fermentable [194].

Recently, FAO/WHO discussion document on carbohydrates recommended

dropping the terms ‘‘soluble’’ and ‘‘insoluble’’ fibre (FAO, 1998). According to

Schweitzer and Edwards the physiological effects of Total Dietary Fibre (TDF), in

the forms of insoluble and soluble fractions of foods, have a significant role in

human nutrition [195].

According to Jenkins et al the polysaccharides comprising a major part of DF

in fruits and vegetables are beneficial to healthy human volunteers, since the

consumption of fibre lowers plasma cholesterol levels [196].

A range of approaches have been employed to test hypothetical ways in

which dietary fibres could bring about the observed reduction of disease risks,

including a number of well-designed studies that acute benefits of dietary fibre-based

meal consumption, such as glycemic index and effects on satiety. However, it is

likely that acute responses to meals will not necessarily result in health benefits.

According to Gordon the epithelium of the intestinal is believed to be completely

replaced by new cells at every 2–3 days. In particular, long-term animal feeding

studies would suggest that higher dietary fibre intake results in increased crypt and

villus length within the intestine and increased digestive secretion output in pig and

man which is suggestive of longer term adaptive responses of the body to dietary

fibre intake that allow better absorption. Such adaptive mechanisms may offset any

acute beneficial effects of dietary fibre intake [197].

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According to McKinley and Story, the US Food and Drug Administration has

only granted specific health claims for (soluble) fibres with reducing cardiovascular

disease risk for 3g/day of β-glucan from whole oats or barley or 7g/day of Psyllium

husk in 2006, based on a number of supportive, randomized and controlled trials

[198]. Other sources of dietary fibre require similar randomized controlled trials to

be carried out before health claims can be justified.

Ahmed discussed that there is much epidemiological evidence of the role of

DF in disease prevention. Bingham reported that there is an inverse relationship

between fibre intake and the incidence of obesity, heart disease, cancers (of the colon

and breast), diabetes and gastrointestinal disorders.

2.4.5 Physiological functions of SDF

2.4.5.1 Fibre and colon health

Burkitt et al and Cummings et al studied the effect of SDF in the colon, DF

tends to increase fecal bulking due to increased water retention and the IDF reduces

transit time. This is particularly important since the conversion of sterols to

carcinogenic polycyclic aromatic hydrocarbons is known to occur with time.

Epidemiological evidence suggests that low fecal weights are associated with an

increased risk of cancer of the colon [199,200]. Madar and Odes also reported that

DF may also bind toxins, bile acids and carcinogens [201].

The main effect of SDFs is associated with the viscous polysaccharides such

as pectins and gums, which decrease the assimilation of nutrients. The bacterial mass

that is formed from the high fermentable substances (pectins), the residues of the less

fermentable polymers (cellulose and hemicelluloses) and the water retained by them

are responsible for the increase of the fecal bulk [202].

According to Shrivastva and Goyal SDF not only performs certain important

physiological functions but also builds up important microflora by acting as a

substrate food for beneficial microorganisms; therefore, it acts as a prebiotic and

improves host health. A prebiotic aims selectively to feed probiotic organisms

indigenous to the human colon [203].

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Also, research has indicated that fibre protects against inflammatory bowel

diseases as explained by Galvez et al such as Crohn’s disease and ulcerative colitis

by increasing production of short-chain fatty acids (SCFAs), which act as

immunomodulators in the inflamed intestine and also by increasing the proportions

of beneficial rather than pathogenic bacteria that make up the gastrointestinal

microflora [204].

2.4.5.2 Fibre and Heart disease

According to Ma et al soluble fibre intake has been associated with protective

effects against C-reactive protein (CRP), a marker of acute inflammation recognized

as an independent predictor of future cardiovascular disease and diabetes. Thus, an

inverse relationship has been found between DF intake and CRP concentration [205].

Truswell and Beynen found in their research that the most of the water-

soluble fibres have hypocholesterolemic properties, possibly due to inhibition of fat

digestion and absorption and inhibition of cholesterol synthesis in the liver by

propionate or other bacterial products and the action of viscous NSPs on insulin and

other hormone secretions [206].

Animal studies suggest that dietary fibres bind bile acids in the intestine. This

effect results in increased fecal losses of bile acids, which are normally reabsorbed in

the terminal ileum. As a result, the liver must produce new bile salts, for which

cholesterol is used as a starting material. According to Van Rosendaal et al this

interruption in the normal billiary circulation would also be expected to occur within

the human gut, and offers insight into the potential of certain dietary fibres to reduce

total body, and as result plasma cholesterol concentrations [207].

2.4.5.3 Fibre and its role in Diabetes, Diverticulosis and Constipation

Wolever and Jenkins [208] described that dietary fibre is fermented by

bacteria in the large intestine leading to the formation of shortchain fatty acids,

which acidify the colonic content resulting in water retention and feacal bulking

complex which promotes laxation. It gives a feeling of satiety, slows down the

appearance of post prandial glucose levels in the blood leading to a gentle rise in

47

blood sugar. According to Goldman et al [190] Dietary fibre also enhances stable

blood sugar levels which allow less demand on the insulin mechanism that is needed

to convert sugar from the blood into usable energy. It helps to control weight by

delaying the return of hunger, promotes good intestinal health by increasing viscosity

of intestinal contents, bowel motility and decreases transit period through the

intestinal tract, which may help in reducing colon and rectal cancers and also

diverticulosis. It binds bile acids and lipid substances such as cholesterol and

promotes their excretion thereby lowering the plasma cholesterol and reducing the

risk of heart disease.

2.4.5.4 Fibre and its other role

Anderson and Tietyen-Clark (WHO/FAO, 2003) stated that DF may be

beneficial in weight reduction and in the control of diseases such as hypolipidaemia

and diabetes [209].

Flickinger and Fahey reported that dietary fibres - prebiotics not only have

physiological significance in human diets, it also started gaining attention of pet

owners, pet food manufacturers, livestock producers and feed manufacturers [210].

Although SDF have little or no effect on carbohydrate metabolism, but are

found to reduce postprandial glucose excursions [211].

Apart from their functional behaviors, these low viscosity fibres are also used

by food processor and food makers to modify texture, rheology, because they

influence colligative properties of food systems and improve marketability of the

food product as a health promoting or functional product [212].

According to Femenia et al [213] DF derived from fruits and vegetables have

a relatively high proportion of SDF; this kind of fibre shows functional properties,

such as water holding, oil holding, swelling capacity, viscosity or gel formation,

among others, which have been more useful for understanding the physiological

effects of DF, than the chemical composition alone.

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2.4.6 Recommended Dietary Allowances (RDA) and Intakes of Dietary fibre

The recommendations regarding the intake of DF are not the same in all

countries. The United Kingdom proposes 18g/d of DF expressed as NSPs, while an

amount of 30g/d has been proposed by Germany, and in the United States the

specified intake should be 38g/d for men and 26g/d for women. The DF intake

ranges between 30 and 38g/d for males whereas a value of 21 to 26g/d has been

proposed for females by National Academy of Sciences, Food and Nutrition Board,

U.S.A. (www.dietary-fiber.info/#recommendation).

Similar information has been cited for the DF intake at

(www.creationsmagazine.com /articles/C111/Boutenko.html) wherein the U.S. RDA

for fibre is 30g/d and an average American consumes between 10 and 15g of fibre

per day. An average Indian diet contains about 6 to 8.5g of crude fibre [214].

According to Mori et al some organizations suggested 10g DF/1000 kcal as

an interim recommendation [215] and Food and Nutrition Board (2002), Institute of

Medicine, USA recommended approximately 14g TF/ 1000 Kcal. In January 2007, a

Corrigendum to EU Regulation (EC) No 1924/2006 (OJ 409 p9 30.12.2006 on

nutrition and health claims made on foods was published, taking effect from 1 July

2007.

http://eurex.europa.eu/LexUriServ/site/en/oj/2007/l_012/l_01220070118en00030018

.pdf. This specifies “A claim that a food is a source of fibre, and any claim likely to

have the same meaning for the consumer, may only be made where the product

contains at least 3g of fibre per 100g or at least 1.5g of fibre per 100 kcal”.

The elaborated discussion in this chapter revealed the known factors of amla

such as bioactive compounds, role of active compounds in health, outcome of

previous clinical studies, products and technologies developed for amla products etc.

The terminologies for nutraceutial and functional foods/ compounds were mentioned

for better understanding of the work. The third and fourth topics given clear view on

the previous studies on dehydrated amla and pomace / residue incorporated biscuits.

This part revealed the areas which were unexplained in amla based food products.

So, the present work was designed in such a way to explore the unexploited areas.

49

Hence, amla pieces with spices and amla residue incorporated breads were

developed. In the first product, osmotically dehydrated amla pieces were developed

by using brine solution with three spices. The biochemical, physical parameters and

sensory attributes of the product during different stages of processing were studied to

give significant contribution to the product developed in this work. The other

product is amla residue incorporated bread. Bread was developed with incorporating

dietary fibre from many sources including synthetic one. At the same time not much

work were done on amla residue incorporated bread except knowing dietary fibre

content of it. The second part of the present work was done to see the effect of amla

residue incorporation on the functional properties of bread such as dietary fibre

(soluble and insoluble dietary fibre) content, volume of bread, texture profile,

sensory attributes etc. The bread was developed as per RDA of dietary fibre per 100g

of food. Hence, background information of the work was used for the present work.