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Simple Carbohydrates. M. Burns FCS 3120. Today’s Plan. Discuss frozen dessert lab review Discuss exam 1 Lecture Assignment of homework Sugar display. Functional properties. Flavor: Sweetness Color: Maillard reaction Texture Bulking agent Source of food for yeast
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Simple Carbohydrates M. Burns FCS 3120
Today’s Plan • Discuss frozen dessert lab review • Discuss exam 1 • Lecture • Assignment of homework • Sugar display Burns, 2008
Functional properties • Flavor: Sweetness • Color: Maillard reaction • Texture • Bulking agent • Source of food for yeast • Preservative (jellies, jams) Burns, 2008
Physical properties • Sweetness • Varies with type & temperature • Hygroscopicity • Ability to attract & hold water • Solubility • Varies with type & temperature Burns, 2008
Chemical reactions • Degradation • Opening of ring structure • Hydrolysis • Splitting of the sugar molecule • Inversion • Carmelization • Melting of sugar (170C, 320F) Burns, 2008
Chemical reactions • Maillard reaction • Non-enzymatic browning that occurs when a protein and a sugar are heated • Condensation of a reducing sugar & an amine • pH of 6 accelerates • Acceleration increases as temperature increases Burns, 2008
Food Applications • Crystalline candies • Amorphous candies • Syrups, sauces, jellies, & jams • Baked products Burns, 2008
Crystalline candies • Small, organized sugar crystals • Smooth & easy to bite • Fudge, penuche, and fondant • Basic ingredients of sugar & water • Other ingredients can be added to enhance flavor Burns, 2008
Principles of Crystallization • Increased solubility, decrease ease of crystallization • Solubility of sugar increases with temperature, thus crystallization decreases. • Supersaturation necessary Burns, 2008
Preparation of Crystalline Candies • Dissolve sugar completely • Concentrate the solution to the appropriate degree • Thermometer or cold water test • Supersaturation and cooling • Initiate and control crystallization Burns, 2008
Interfering Agents • Temperature • Higher temp. = firmer texture • Lower temp. = softer candy • Agitation • Acid (cream of tartar, brown sugar) • Sugars other than sucrose (corn syrup) • Fat (butter, chocolate) • Protein (milk, cream) • Foams (egg white) Burns, 2008
Changes during Storage Soft and smooth texture Ripening Coarse and more gritty texture Burns, 2008
Crystalline candies: Evaluation • Sensory: holds shape when cut, velvety smooth mouthfeel • Firmness • Gritty texture • Too little agitation, premature initiation of crystallization, or too few interfering agents Burns, 2008
Amorphous Candies • Lack an organized, crystalline structure due to high concentration of sugar (90%) and/or interfering agents • Very viscous when removed from heat • Caramels, taffy, peanut brittle, toffee Burns, 2008
Preparation of Amorphous Candies • Sugar, water and fat • Dissolve sugar completely • Concentrate solution to appropriate degree • Usually higher than crystallized candy • Solidification Burns, 2008
Amphorous Candies: Evaluation • Color • Uniform golden brown with the exception of taffy • Flavor • Texture will vary with the candy • Cooking, not cooling, is crucial Burns, 2008
Types of sweeteners • Sugar • Syrups & liquid sugars • Alternative sweeteners • Polyhydric alcohol (Table 8.5) • Sugar substitutes (Table 8.6) Burns, 2008
Substituting Sweeteners • Functional properties • Solid vs. liquid • Nutritional considerations • Bulking agents • Table 8.7 for substitution list • Ideas for project!! Burns, 2008
Homework • Simple CHO lab next class • CHO worksheet due Burns, 2008