NUTR 211Final Exam ReviewNew Information for FinalFlour MixturesA. composition1. dry ingredientsa. flourb. sugar (sometimes considered wet)c. leavening agentsd. salte. (Herbs and spices)2. wet ingredientsa. waterb. milkc. fat d. eggs3. types and proportions determine different sensory characteristics in various productsB. flours1. provide structure, texture, and flavor2. gelatinized starch strengthens the ‘crumb’a. soft, interior part of the breadb. created by gelatinization of starch in flourc. coagulation of proteins in flourd. characterized by number and size of air cells e. fine crumb: small, uniform air bubblesf. coarse crumb: large, irregular air cells 3. nut flours and coconut flours are more bulk flours and you would need something else to provide the starch characteristicsC. starch1. wheat flour is 80% starch2. starch+ liquid+ heat=gelatinization of starcha. hydrated starch at ideal temperature, swells starch granule, bursts, thickens mixtureb. once all starch granules have burst>solid mass 3. it is partially hydrolyzed by amylases present in floursa. starch> dextrins, malt, and glucoseb. these shorter carbohydrate fragments impart: sweetness, crust color, fermentation improvement D. gluten1. class of storage proteins (prolamins) in wheat, rye, barley, and oatsa. wheat=gliadin (also glutelins, aka glutenin)b. rye=secalinc. barley= hordeind. oats= avenin2. contributes to the firming of flour mixtures3. ability to rise related to amount of gluten in flour 4. water soluble and insoluble protein fractions in floura. water-insoluble are gliadin and gluteninb. gluten ball>wash away water-soluble proteins and starch5. gliadin+ glutenin+ water= gluten6. gluten gives ability to expand with inner pressure from leavening gases7. kneading: stretching and folding the dough forms pockets that are stretched when gases expand 8. when heated, proteins coagulate9. gluten formationa. hydration- gliadin+ glutenin form gluten in presence of waterb. how does protein content of flour affect water required? Higher protein flour requires more waterc. stirring, agitating, and kneading facilitate gluten formationd. proteins in flour wrapped around starch molecules; water and agitation allow proteins tounwind and attach to each other and enhance processE. wheat flour1. soft wheata. cakesb. pastriesc. less protein, more starch2. hard wheata. yeast breadsb. more protein, less starch 3. whole wheat floura. aka graham flourb. whole wheat kernelc. bran cuts gluten strands (negatively impacts volume)d. refrigerate/freeze to prevent oxidative rancidity 4. white floura. bread flour (12-14%): hard wheat, used in production of yeast breadsb. all-purpose flour (11%): less protein than bread flour, blend of hard and soft; breads, cakes, pastryc. pastry flour (9%): soft wheat; pastries, cakes, rich yeast dough, quick breadsd. cake flour (8%): fine grain; smooth textured cakes, bleached to improve color and bakingquality F. leavening agents1. major leavening gasses=air, steam, carbon dioxide2. relative leavening power=carbon dioxide>steam>aira. air: incorporated into flour mixtures by beating, folding, and creaming techniquesb. steam: liquid or ingredients like egg whites; high liquid to flour ratio and high baking temp to produce sufficient steam; ex: popovers, Pâte à choux (choux paste) 3. carbon dioxidea. yeast (saccharomyces cerevisiae)-b. ferment sugar into carbon dioxide and ethanolc. enzymes catalyze fermentation:d. starch hydrolyzed by amylase into maltosee. maltase hydrolyzes maltose into glucosef. baking soda (sodium bicarbonate): without acid, produces sodium bicarbonate, which has a yellow color and a bittery-soapy flavor; acid prevents formation of ‘washing soda’; used in baking with acid ingredients- buttermilk, molasses, brown sugar, honey, citrus fruit juices, applesauce, vinegar, cocoa and chocolate g. baking powder= baking soda +acid (ex: cream of tartar) h. baking powder +liquid= CO2i. single acting: produce CO2 once liquid added; wait to long> reduce leavening j. double acting: in addition to fast acting acid ingredient, another acid that reacts when heated is part of baking powder mixk. troubleshooting:l. too much leavening: baked product falls, low volume, coarse texturem. too little leavening: compact, heavy productG. sugar in flour mixtures1. sweetens2. browns3. tenderizes>interferes with gluten development4. leavensa. feeds yeastb. adds air via creaming5. increases coagulation temperatures of proteins and gelatinization temperature of starcha. more time for gluten stretch; increases volume6. troubleshootinga. too much sugar= dry, gritty, doesn’t brown, caved in, coarser, gummyb. too little sugar=flat, dry, bland, bitter, dense, inhibited browning, less tenderH. fat in flour mixtures1. interferes with gluten formation by shortening strands of gluten>tenderizes2. “shortening” power of fatsa. lard> hydrogenated fats> butter> oilsb. presence of emulsifiers (mono and di glycerides) fat dispersed more evenly, increased volume in cakes with fine texture3. fat in leavening a. plastic fats trap air bubbles when creamed with sugar4. troubleshootinga. too much fat= weakens structure, decreases volume b. too little fat= tougher crumb I. Eggs in flour mixtures1. incorporates air into batter2. structure from coagulated proteins3. leavening from water 4. troubleshootinga. too much egg= tough, rubbery textureb. too little egg= decreased volume, reduced structural strength J. liquid in flour mixtures1. hydrates starch for gelatinization and gliaden and glutenin for gluten formation2. activates baking soda/ powder3. rehydrates yeast4. troubleshootinga. too much liquid= decreased volume; too moistb. too little liquid= dry texture; decreased volumeK. salt in flour mixtures1. flavor2. firms dougha. adjusts swelling capacity of gluten; prevents over-hydration 3. improves texture4. controls yeast growtha. without fermentation would be too rapidL. high altitude baking1. lowers boiling point of liquids, more water lost during baking via evaporation2. reduces atmospheric pressure> can over expand and collapse before set3. adaptationa. use less leavening, fat, sugarb. use more liquid and flourc. bake at higher temps to set structure quickly Quick BreadsA. goal is tender crumb1. mix only dry ingredientsB. batter vs dough (characterized by ratio of dry to wet ingredients) 1. pour batter: thinner, less flour (1:1)2. drop batter: more flour than pour batter (2:1)3. dough: more flour than drop