Date of Award:

5-1977

Document Type:

Thesis

Degree Name:

Master of Science (MS)

Department:

Nutrition, Dietetics, and Food Sciences

Department name when degree awarded

Nutrition and Food Sciences

Committee Chair(s)

C. A. Ernstrom

Committee

C. A. Ernstrom

Committee

Gary Richardson

Committee

Von Mendenhall

Abstract

Whey from a commercial cheese plant, taken at draining on five separate days, from cheese made with a Mucor miehei coagulant was cooled within 1 h to 4 C. Portions were adjusted from pH 4.2 to 6.4 at .2 pH intervals and subjected to HTST pasteurization at 73.9, 76.6, and 79.5 C for 25 sec. Milk clotting activity in whey was determined before and after pasteurization. Resistance to heat in-activation increased with decreasing pH. All measurable activity was destroyed above pH 5.4 by pasteurization at 79.5 C, above pH 5.8 at 76.6 C and above pH 6.0 at 73.9 C.

Milk clotting activity in Cheddar cheese mad with Mucor miehei remained unchanged for 26 weeks.

Four commercial sterile liquid-milk-based consisting of infant formula, concentrated infant formula, nutritionally complete food, and diet food was aseptically inoculated with sterile Mucor miehei protease solutions to concentrations ranging from 5 x 10-3 to 1 x 10-7 chymosin units/ml of product. The samples were stored at 30 C. After 20 weeks there was no change in the nutritionally complete food. The diet food showed slight whey separation and thickening at 1 x 10-4 CU/ml and coagulation at higher concentrations. The infant formula showed definite whey separation and thickening at 1 x 10-4 CU/ml and coagulation and higher concentrations. The concentrated infant formula showed visible thickening at 1 x 10-3 CU/ml and coagulation at higher concentrations.

Checksum

76867778ff17f37a204931500ef0b7ef

Download

Included in

Food Science Commons

Share

COinS

Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .