Food Chemistry

Water

Freezing

Moisture content

Water activity

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Moisture sorption isotherms

Desorption

Hysteresis

Adsorption

% Relative Humidity

Raoult's Law

Supercooling

Nucleation

Latent heat, sensible heat

Effects of Solute

Lowers freezing point

Freezing time

Factors Affecting aw

Solute

Temperature

Moisture content

Types of Water

Free water

Bound water

Bulk/adsorbed water

Polarity of solute

Size of solute

Affect on reaction rate

Adsorption curve minus desorption curve

Faster nucleation

Hard to define end of crystallization

Simple Carbohydrates

Complex Carbohydrates

Fiber

Non-enzymatic browning

Caramelization

Maillard Browning

Products

Caramelan

Caramelin

Products

Aromatic compounds

Melanoidins

Stages

Initial stage

Intermediate stage

Final stage

Reaction of amino and carbonyl, schiff bases, formation of Amadori and Heyns

1,2 enediol pathway

Higher pH, aromatic compounds

2,3 enediol pathwaay

Lower pH, flavour and colour compounds

Production of melanoidins

Factors affecting rate

Alkaline pH

Water activity

Amino acids

Reducing Sugars

Pentoses > Hexoses

Lysine- amino groups

Tryptophan

Glycine

Monosaccharides > disaccharides

Aldoses > ketoses

Lipid oxidation

Chlorophyll oxidation

Water soluble vitamin degradation

Sweetness

Sweeteners

Sweetness Chemistry

AH-B Theory

AH-B-X Theory

D amino acids

Acesulfame potassium

Aspartame

Sucralose/Splenda

Leucine

Glycine

Tryptophan

Starch

Modified Starch

Resistant Starch

Reducing sugars

Benedict's Reagine

Fehling's Solution

Types 1-5

Pectin

Physical modification

Controlled degradation

Cross-Linking

Substitution of Hydroxyl groups

Gelatinization

Retrogradation

Changes in viscosity

Fructans

Inulin

HM Pectins

LM Pectins

Degree of esterification/methylation

Degree of polymerization

Dextrose equivalency = 100/DP`\

Low DE sugars

High DE Syrups

Starch granules

Birefrigence

Hilum

Amylose

Amylopectin

Soluble fibers

Fermentable fibers

Cellulose