acryl amide presentation

7/29/2019 Acryl Amide Presentation

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ED73.9002: Processing Effectson the functional

components of food

Acrylamide:Thermally inducedToxicant in foods

By-Yakindra Prasad Timilsena (111332)Jyotsna Shrestha Khanal (111328)1

5 Nov, 2010


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Introduction

Mechanisms of formation

ToxicologyAmounts in different food sources

Regulations & allowable limits

Methods of DeterminationPreventive measures

Conclusion

Presentation Outline

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Less tasty side to these culinary delights:

Thermally induced harmful chemicals(Carcinogens)

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Synthesized for the first time in 1949

Unsaturated & highly reactive amide White odorless crystalline solid, soluble in

water, ethanol, ether, and chloroform

Formation: baking, roasting, toasting,grilling, frying

Common foods: French fries, potato chips,

bread, biscuits, coffee, roasted cereals

What is

Acrylamide ?


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S.N. Properties Values1. IUPAC name Prop-2 enamide

2. Molecular formula C3H5NO

3. MW 71.08 g mol1

4. Density 1.13 g/cm3

5. Melting point 84.5 C

6. Solubility in water 2.04 kg/L (at 25 C)

7. Color white crystalline solid

8. Boiling point 136 C

Properties of Acryl amide

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1950s: Synthetic Polyacrylamide-based

flocculants

1960s: Synthetic coagulants in mineral processing

industries 2002: Swedish researchers announced the

discovery of acrylamide in food

Acrylamide in industrial use

6PAM


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Cereals, potato & coffee : variety and growing factors

Cereals : reducing sugars are abundant conc. Of

Asparagine AA

Potato : asparagine is abundant conc. of reducing sugar

AA

Acrylamide production in foods

Concentrations

& availability of

Precursor

molecules

AA Formed by

Maillard reaction

between asparagine

and reducing sugars

(precursors)

Factors (temp.,

heat intensity,

water activity)

in processing

technologies

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Impact of Potato variety on AA Levels

(Source: D. Mottram, U. Reading)

1200012800Over cooked

35003500Cooked

100200

Frozen frying chips

as sold

35002800Chipped & friedNd


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Acryl

amide

formation

Heat

Carbonyl

source

L-Asparagine

source

Removing or changing one of the parameter

prevents formation.9


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Mechanism for formation

CCH2CH

NH2

COOHO

H2NHO

OH

OH

OH

OH

O+

CCH2CHN

COOHO

H2N

Asparagine Glucose

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From Asparagine and Reducing sugar


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Maillard reaction

Products

CCH2CH

N

COOHO

H2N

CCH = CH2

O

H2N

CCH2CH2N

O

H2N

- CO2

Acrylamide

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From Asparagine and Reducing sugar


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12

Acrylic acidAcrolein


From Triglycerides

Triglycerides

Heat, O2

Acrylamide

NH3


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Variation in concentration of Acrylamide

with temperature and time

Acrylamide

(ppm)

Temperature (0C)

2.5 min

3.5 min

Source: Gertz and Klosterman (2002) Eur. J. Lipid Sci. Technol. 104:762-771. 13


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380 400 420 440

Temperature (Kelvin)

0

5

000

10000

15000

20000

Acrylamide(pp

b)

AA Formation as a function of Temperature

AA = 442.3 * e(0.07930*(Temp-383))

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Potato chips

Frying time: 15 minutes


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Effect of pH on Acrylamide Formation

AA(p

pb)

pH

120 C, 40 min

150 C, 15 min

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Effect of browning in AA formation

(Source: D. Mottram, U. Reading)

1200012800Over cooked

35003500Cooked

100200

Frozen frying chips

as sold

35002800Chipped & friedNd


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Amount of Acrylamide in Foods (ppm)

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Category European Data FDA Data

Breads 12-3200


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Amount of Acrylamide in Foods (ppm)

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Category European Data FDA DataMeats < 30-64 < 10-116

Candy and Dessert items < 20-110 < 10-909

Cookies 36-199

Coffee and Tea 170-700 175-351

Other Nonalcoholic Beverages < 30

Alcoholic Beverages 30

Dairy Products 10-100 < 10-43

Baby Food and Formula 40-120 < 10-130

Dry Soup Mixes < 10-1184

Gravy and Seasonings 38-54


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Amino Acids Level of Acrylamide Formation

Alanine


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Food product Interval

(month)

Acrylamide level (g/kg)

Initial Second

Breakfast cereal 12 238 238

Soluble coffee powder 12 771 256

Roasted barley 9 265 225

Roasted coffee 7 203 147

Dried chicory 5 214 174

Roasted chicory 5 4015 3395

Cocoa 3 180 177

Chocolate with almond 2 94 73

Soluble chocolate powder 1 54 41

Stability of acrylamide in various foodstuffs

Adapted from Delatouretal.


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Asparagine in Various Crops

Cheese 40300 mg/100gm

Asparagus 5.4108 mg/100gm

Cocoa (raw) 30.9 mg/100gm

- roasted @ 1250C 14.5 mg/100gm

- roasted @ 1350C 9.4 mg/100gmPotato 5001000 mg/100gm

Rye 0.22.8 mg/100gm

Wheat 0.220 mg/100gm

Corn 0.61 mg/100gm

Source: Ellin Doyle, Ph.D., Food Research Inst., U. Wisc.

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Known neurotoxicant (IARC 2002; Manson et al. 2005)

Peripheral neuropathy

Tingling/numbness of extremities

Loss of reflexesChronic CNS dysfunction and neuropathy

Reproductive toxicity

Animal carcinogen (CNS, endocrine organs)

EPA has classified acrylamide as a B2 carcinogen(probable human carcinogen) (IRIS2009).

Biomarkeradducts on amino acid valine of Hb.

Toxicology

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2 micrograms per kg body weight

per day(Office of Environmental Health Hazard Assessment)

Exposure at a level 1,000 times greater than the MADL is

expected to have no observable effect

No Observed Adverse Effect Level (NOAEL) of 15 mg/kgbw/day were identified in mice

Legislation under formulation

Maximum allowable dose level (MADL


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Water extraction

Analysis by GC-MS with or w/o

bromination by LC-MS/MS

by LC-MS or -UV after deriv. with

mercaptobenzoic acid GC-Ion Trap MS

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Acryl amide extracted with water, test

portion homogenized, acidified to pH 4-5

Addition of Carrez I and Carrez II solution

Extraction with Ethylacetate hexane (80:20),

Filtration over Na2SO4

Clean up with Flourisil elution of

acrylamide with acetone

Evaporation, residue taken up in

ethylacetate, triethylamine added

Filtration, injection into GC-MS

GC-MS

method


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Acrylamide Precursors Where to

Intervene

Asparagine Reducing Sugars- Glucose- Fructose

- Sucrose hydrolysis?

Factors affecting asparagine and reducing sugars

- Variety of potato

- Storage conditions


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Acrylamide Possible Mitigation Strategies

1. Reduction or removal of sugars.

Selection of low sugar cultivar.

Blanching and soaking to leach out sugars.

2. Reduction or removal of asparagines.

Use of enzymes to degrade asparagine during foodprocessing.

Blanching to leach out asparagine

3. Blocking formation of Acrylamide

Altering time-temperature of processing. Altering heat processing methods

Changing pH of food by using acids

Use of antioxidants


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Reduction of Acrylamide

formation in Potatoes products

Improve agronomic practices

Select potatoes variety with less asparagine

Store potatoes tubers >10C

Blanching (82C)

Add antioxidants

Dip slices in citric acid (0.75%) solution

Dip in NaCl, CaCl2 solution Use of enzyme- asparaginase

Addition of amino acids glycine.28


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Reduction of Acrylamide

in cereal products

Adjustment of time and temperature duringbaking.

Extend fermentation times where feasible.

Substitution of ammonium bicarbonate withalternatives

Avoid or minimize use of reducing sugars

Avoidance of very high baking temperature

Use of asparaginase in dough to degradeasparagine.

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Enzyme mechanism

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Impact of treating with Asparaginase

By treating with asparaginase there was a

99% reduction in the levels of

acrylamide in the potato mixture

Product characteristics fully preserved

No change in process parameters

Commercially viable and available ???


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Biscuit / Cookies

All Other Foods

Relative Exposure to Acrylamide in U.S. Food

French Fries &

Potatoes

Breads

Potato Chips

Cereal

Coffee

Cakes

Dried Foods

Pop Corn

Salty Snacks

Chocolate Products

Nuts/Seeds/Butters

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Conclusion

Acrylamide formation in thermally

processed foods is a major challenges for

bakery, French fries and chip producing

industries.

challenges still remain in terms of the needs

to develop simple and rapid test methods.

different pre-frying treatments on the

reduction of acrylamide (AA) formation are

under investigation 33


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What about these cereal based foods ?

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ChapatiDoughnut

Selroti Puri


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Foods should not be cooked

excessively...for too long or at too higha temperature... However, all

foodshould be cooked thoroughly to

destroy food borne pathogens.

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Is it possible to cook food withoutforming at least some AA ?????

acryl amide presentation

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