HTM 2700 Lecture Notes - Lecture 8: Bain-Marie, Hydrolysis, Corn Starch

• School: University of Guelph
• Department: Hospitality and Tourism Management
• Course: HTM 2700
• Professor: Alison Crerar

Document Summary

Raw starch(the powder) and cold h2o forms a suspension. Starch cooked in h2o forms a colloidal dispersion. Sources of starch: roots eg) potatoes, arrowroot, tapioca found in plastids in the cytoplasm, cereals eg) wheat, rice, corn found in the endosperm of the grain. Amylose linear chain molecules polymer of glucose actual number of glucose molecules depends on source of starch glucose molecules joined together by alpha 1,4 glycosidic linkage human body can break these linkages therefore, starch is a source of energy. Amylopectin branched molecule(bushy, but compact) also a polymer of glucose at the branching points, glucose molecules are joined by alpha 1,6 glycosidic linkage also a source of energy. Within starch granules, hydrogen bonds between starch molecules (amylose and amylopectin) are broken starch granules expand in size as h2o moves into granules, amylopectin stays in sol is created. Cereal starchs contain more amylose than root starches. Wheat starch include flour: 25% amylose (cereal starch)