food chemistry - -food component and reactions - -analytical food chemistry - -- food -...
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Food chemistry-Food component and reactions-Analytical Food Chemistry-- Food -Palatability, Energetic, functional
Water in food -The importance of water-Water content in different food articles-Milk, Meat, Bread, Honey, Butter, oilTransportation/ stabilization of the body temperature/ reactant/ solvent-The Importance of water in foodTechnological aspectsShelf life ( Hydrolytic reactions)/ textureEconomic aspects
►Chemical structure of Chemical structure of waterwater
►Water as a polar solventWater as a polar solvent►Affinity to sugar s ,Ions Affinity to sugar s ,Ions and polar groupsand polar groups►Hydrogenic boundHydrogenic bound►Ionic interactionIonic interaction
Solute/SolventSolute/Solvent ُ ُ nm)nm) 1<1<))SolutionsSolutionscolloids (1-100nm)colloids (1-100nm)
Dispersion/ Continues Dispersion/ Continues HydrocolloidsHydrocolloids100<nm)100<nm) ) )SuspensionSuspension
Moisture,Moisture, water activity,water activity,
Relative humidityRelative humidity
►aw= Pf/Paw= Pf/P00
►Rh= Pa/PRh= Pa/P00
ERh= Rh=aW × 100ERh= Rh=aW × 100
Moisture and awMoisture and aw
Moisture and awMoisture and aw
The effect of water activity The effect of water activity in shelf life of foodsin shelf life of foods
MineralsMinerals macro element/microelementmacro element/microelementessential (essential (macronutrient & micronutrientmacronutrient & micronutrient)/ possibly )/ possibly essential/ essential/ nontoxic –non essential/ toxicnontoxic –non essential/ toxic
Different parameters affects mineral content Different parameters affects mineral content of food of food
componentcomponent
Pre-harvest processingPre-harvest processing
Post-harvest processingPost-harvest processing fortification fortification
(enrichment(enrichment))►RestorationRestoration►SupplementationSupplementation►StandardizationStandardization
Chemical statues of minerals in foodChemical statues of minerals in food
►SolubleSoluble►Non-soluble Non-soluble
Chelatets ( chlorophyll, hemoglobin/ Chelatets ( chlorophyll, hemoglobin/ cyanocobalamin), calcium caseinate cyanocobalamin), calcium caseinate
ChlorophyllChlorophyll
Phytic acidPhytic acid
Minerals in food processingMinerals in food processing
OxidationOxidation
TasteTaste
Catalists in Hydrogenation ( with special Catalists in Hydrogenation ( with special reference to nickel)reference to nickel)
ColorColor
texturetexture
Salting in /salting outSalting in /salting out
CarbohydrateCarbohydrate
►Human derive their energy mainly Human derive their energy mainly from carbohydrate (55%-65%)from carbohydrate (55%-65%)
►MonosaccharideMonosaccharide►OligosaccharidesOligosaccharides►PolysaccharidesPolysaccharides
MonosaccharideMonosaccharide
►StereoisomerStereoisomer► epimer epimer DiasteromerDiasteromer ►EnantiomerEnantiomer
EnantiomerEnantiomer
L- (+)-Tartaric acid D(-)-Tartaric L- (+)-Tartaric acid D(-)-Tartaric acidacid
Anomer,EpimerAnomer,Epimer
Hemiacetal formation in Hemiacetal formation in glucoseglucose
Hemiketal formation in Hemiketal formation in fructosefructose
ReactionsReactions
11 - -Reduction to sugar alcoholsReduction to sugar alcohols
ReactionsReactions
►22))Oxidation to Aldlonic acids/ Aldaric Oxidation to Aldlonic acids/ Aldaric acids/ uronic acidsacids/ uronic acids
11))SugaraminSugaramin
Sugar derivativesSugar derivatives
22))GlycosidesGlycosides
AmygdalinAmygdalin
GlycosylaminGlycosylamin
►N-Glycosides/ S- GlyosidesN-Glycosides/ S- Glyosides
Maillard reactionMaillard reactionThe carbonyl group of the sugar reacts with the amino group of the amino acid, producing N-substituted glycosylamine and water
The unstable glycosylamine undergoes Amadori rearrangement, forming ketosamines
There are several ways for the ketosamines to react further:
Produce 2 water and reductones
short-chain hydrolytic fission products can be formed
Produce brown nitrogenous polymers and melanoidins
Factors affecting Maillard Factors affecting Maillard reactionreaction
High temperature, intermediate moisture levels, and alkaline conditions all promote the Maillard reaction.
In cooking, low moisture levels are necessary mainly because water boils into steam at (100 °C), whereas the Maillard reaction happens noticeably around (154 °C): significant browning of food does not occur until all surface water is vaporized.
The rate of Maillard reactions increases as the aw increases from 0.0 or as it decreases from 1.0, reaching a maximum at water activities in the range of 0.6 to 0.7. Since the Maillard reaction produces water, further increases in water activity may inhibit Maillard reactionsPentose reducing sugars react more than hexose, which react more than disaccharides . Different amino acids produce different amounts amounts of browningof browning..
Action of acids and alkaline Action of acids and alkaline on saccharineon saccharine
11 ) )Action of acid: Removal of water, Action of acid: Removal of water, Cyclyzation, Furfural from pentose andCyclyzation, Furfural from pentose and
hydroxy methyl furfural from hexosehydroxy methyl furfural from hexose
2) Action of Alkaline : Epimeration, 2) Action of Alkaline : Epimeration, Isomeration, Unstable IntermeIsomeration, Unstable Interme
Oligosaccharide formationOligosaccharide formation
ΒΒ-Lactose-Lactose
ΒΒ-Maltose -Maltose
IsomaltoseIsomaltose
SucroseSucrose
SucroseSucrose
Invert sugarInvert sugar
RaffinoseRaffinose
StacchioseStacchiose
CellobioseCellobiose
PolysaccharidesPolysaccharides
HomopolysacchridesHomopolysacchrides
Starch, Inolin, GlycogenStarch, Inolin, Glycogen
HeteropolysaccharidesHeteropolysaccharides
Hemicellulose, pectin, gumsHemicellulose, pectin, gums
StarchStarch
The basic structure of The basic structure of amyloseamylose
Starch degradationStarch degradation
Starch molecules are Starch molecules are HydrolyzedHydrolyzed by by
Enzyme or acidEnzyme or acid
Dextrose equivalentDextrose equivalent Dextrin ized starchDextrin ized starch
Starch gelatinizationStarch gelatinization
High Fructose Corn Syrup (HFCS), commonly used to sweeten soft drinks, is made by
treating corn syrup with enzymes to convert a portion of the glucose into fructose. Commercial HFCS contains from 42% to 55% fructose, with the remaining percentage being
mainly glucose.
GlycogenGlycogen
Inulin Inulins are present in many vegetables and fruits, including onions, garlic, bananas, asparagus/ artichokes. Inulins, also
called fructans, are polymers consisting of fructose units that typically have a terminal glucose.
Oligofructose has the same structure as inulin, but the chains consist of 10 or fewer fructose units. Oligofructose has approximately 30 to 50
percent of the sweetness of table sugar.
Inulin is less soluble than oligofructose and has a smooth creamy texture that provides a fat-like mouthfeel. Inulin and oligofructose are nondigestible by human intestinal enzymes,
but they are totally fermented by colonic microflora. The short-chain fatty acids and lactate produced by fermentation
contribute 1.5 kcal per gram of inulin or oligofructose. Inulin and oligofructose are used to replace fat or sugar and reduce the
calories of foods like ice cream, dairy products, confections and baked goods.
CelluloseCellulose
Cellulose
►1000 unitis of glocose►Intra & inter hydrogenic bounds is
stabilizing the unique structure as the amorphous or crystalline stricture
►Production of glucose syrup from cellulose
lignin should be acid hybridized prior to► enzymic hydrolyse
The difference between The difference between cellulose and hemi cellulosecellulose and hemi cellulose
►Number of units ►Variation in building block sugars ►Chains ►Xylose, mannose, galactose,
rhamnose, arabinose ►In acidic form
Hemicellulose (Hemicellulose (Xylan, Arabinogalactane))
Hemi cellulose and pentosans
PectinsPectins
Pectin
►Pectinic acid►Molecular w., methylasion D, Osmotic pressure, pH ►H.M.P 3.5=pH, high OP►M.M.P 3.5 <pH Medium OP ► L.M.P Ca Iones ►Pectic acid
GumsGums
Seed gums ( Carnob,Guar)Seed gums ( Carnob,Guar)
Exudate gums ( arabic, Tragacanta) Exudate gums ( arabic, Tragacanta)
AlgaAlga
Microbial gums (Dextan, Xanthan)Microbial gums (Dextan, Xanthan)
DextranDextranDextran is a polysaccharide similar to amylopectin, but the main Dextran is a polysaccharide similar to amylopectin, but the main
chains are formed by 1α→6 glycosidic linkages and the side chains are formed by 1α→6 glycosidic linkages and the side branches are attached by 1α→3 or 1α→4 linkages. Dextran is an branches are attached by 1α→3 or 1α→4 linkages. Dextran is an oral bacterial product that adheres to the teeth, creating a film oral bacterial product that adheres to the teeth, creating a film called plaque. It is also used commercially in confections,, as called plaque. It is also used commercially in confections,, as
food additivesfood additives , ,
Vitamins ( Chemical structure) Stability Functionality Fat soluble Water soluble
Fat soluble vitamins Fat soluble vitamins
Vitamin AVitamin A
Fat soluble vitamins Fat soluble vitamins vitamin D2 , D3 vitamin D2 , D3
Fat soluble vitamins Fat soluble vitamins vitamin E vitamin E
Fat soluble vitamins Fat soluble vitamins vitamin E vitamin E
Antioxidant activity of vitamin EAntioxidant activity of vitamin E
Fat soluble vitaminFat soluble vitaminVitamin KVitamin K
Water soluble vitaminWater soluble vitaminVitamin CVitamin C
11 ) )Anti oxidantAnti oxidant
22 ) )Chelating agentChelating agent
33 ) )UnstableUnstable
Water soluble vitaminWater soluble vitaminvitamin B1vitamin B1
Water soluble vitaminWater soluble vitaminvitamin B2vitamin B2
Water soluble vitaminWater soluble vitamin
Vitamin B3Vitamin B3
Water soluble vitamin, Water soluble vitamin, vitamin B5vitamin B5
Water soluble vitamin , vitaminB6Water soluble vitamin , vitaminB6
Vitamin B8Vitamin B8
Vitamin B9Vitamin B9
Vitamin B12
Food additivesFood additives
►Nutritive valueNutritive value Vitamins, Amino acids, MineralsVitamins, Amino acids, Minerals,,
Sensory valueSensory valueFlavor enhancersFlavor enhancers,, : :
Monosodium Glutamate, Nucleotides ,MaltolMonosodium Glutamate, Nucleotides ,Maltol
SweetenersSweeteners
Fructose, Sugar alcohols, SucraloseFructose, Sugar alcohols, Sucralose::Sugar derivativesSugar derivatives
Non sugar derivatives: Sachharin, Non sugar derivatives: Sachharin, Syclamate,AspartameSyclamate,Aspartame , , و و Miraculin, Miraculin,
Glyceyrrhizin,DihydrochalconesGlyceyrrhizin,DihydrochalconesووMonellin, AlitameMonellin, Alitame
MSG)MSG)) ) Monosodium Monosodium glutamateglutamate
IMP GMPIMP GMP
Food additivesFood additives
►Nutritive valueNutritive value Vitamins, Amino acids, MineralsVitamins, Amino acids, Minerals,,
Sensory valueSensory valueFlavor enhancersFlavor enhancers,, : :
Monosodium Glutamate, Nucleotides ,MaltolMonosodium Glutamate, Nucleotides ,Maltol
SweetenersSweeteners
Fructose, Sugar alcohols, SucraloseFructose, Sugar alcohols, Sucralose::Sugar derivativesSugar derivatives
Non sugar derivatives: Sachharin, Non sugar derivatives: Sachharin, Syclamate,AspartameSyclamate,Aspartame , , و و Miraculin, Miraculin,
Glyceyrrhizin,DihydrochalconesGlyceyrrhizin,DihydrochalconesووMonellin, AlitameMonellin, Alitame
SucraloseSucralose
SaccharinSaccharin
CyclamateCyclamate
Aspartame and AlitameAspartame and Alitame
MonellinMonellin
►Plant Protein, could be synthesized Plant Protein, could be synthesized duringduring
►yeast or bacterial fermentationyeast or bacterial fermentation
Flavonones Flavonones (Narinigin, neohespiridin)(Narinigin, neohespiridin)
H2H2
Naringin DihydrochalchoneNaringin Dihydrochalchone
Neohespiridin DihydrochalchoneNeohespiridin Dihydrochalchone
Colorant: Colorant:
Caroteoides, Caramels, Titanium oxide, Caroteoides, Caramels, Titanium oxide, Saffron, Annatto, CochinealSaffron, Annatto, Cochineal
Shelf life enhancementShelf life enhancement
Organic acids: pH reducing agents, Organic acids: pH reducing agents, Inhibition of browning reactions(Non Inhibition of browning reactions(Non Enzymatic and Oxidative), Flavouring, Enzymatic and Oxidative), Flavouring, hydrolytic reactions( sucrose hydrolytic reactions( sucrose inversion), Antibacterial propertiesinversion), Antibacterial properties
Sequestering agentSequestering agent
Succinic acid Malic acidSuccinic acid Malic acid
Tartaric acidTartaric acid Fumaric acidFumaric acid
Propionic acid citric acidPropionic acid citric acid
Mineral acidsMineral acids
22 ) )TextureTexture Phosphoric acid 1) WHC Phosphoric acid 1) WHC
::SOSO22
Weak preservative, Inhibition of BrowningWeak preservative, Inhibition of Browning
Propylene Oxide, Ethylene oxidePropylene Oxide, Ethylene oxide
BacteriocinsBacteriocins