Cooking, hydrolysis during

Kinetics studies were conducted at 55°C in a jacketed batch reactor. Shredded wastepaper (10 g / L) was added to 500 mL or 1L of citrate buffer, pH 4.8, and heated to the assay temperature. A specified quantity of either soluble or immobilized cellulase was added to the reactor to initiate hydrolysis. Samples were collected at regular intervals over 30-60 min, and centrifuged to separate solids. The DNS assay (4) was used to detect sugars formed during hydrolysis experiments. The supernatant from the centrifuge tube and the DNS solution were mixed and cooked for exactly 5 min in boiling water. Finally, the sample was transferred to a methacrylate cuvet, and its absorbance was measured at 540 nm. 

Salts and organic by-products, mostly the diol resulting from hydrolysis of the epoxide, from dry cationization are left in the starch. Trimethylamine, if formed, can be detected by its odor. It can be neutralized by subsequent addition of acid. Addition of a slightly soluble organic acid, such as fumaric or adipic acid, during the cationization both eliminates the odor and aids scale control in starch cooking equipment.44... 

During isolation by conventional methods yeast proteins frequently become denatured, insolubilized and display poor functional properties. These proteins can be rendered more soluble by limited hydrolysis with acid, alkali or proteolytic enzymes. Protein hydrolyzates are most commonly prepared by partial acid hydrolysis and yeast hydrolyzates are popular as food flavorings and ingredients (66). Acid hydrolyzates have flavors resembling cooked meats and are widely used by earners to impart brothy, meaty flavors to soups, gravies, sauces, canned meats. 

The structural changes that take place in the starch molecule during dextrinization are not well established. The hydrolysis of the long starch molecules into shorter "chain lengths" is understood however, and this change becomes evident when the dextrin is cooked in water. The viscosity of the dextrin paste will be thinner than that of the starch paste at the same solids level. 

Cooking also inactivates two key enzymes. The first is myrosinase, which hydrolyses glucosinolates into oil-soluble sulfur-containing compounds. The second is phospholipase, which hydrolyses phospholipids into nonhydratable phosphatides. Myrosinase activity has been extensively studied and is carefully controlled during the cooking operation that minimizes hydrolysis of glucosinolates and reduces... 

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