Date of Award:

5-1974

Document Type:

Thesis

Degree Name:

Master of Science (MS)

Department:

Nutrition, Dietetics, and Food Sciences

Department name when degree awarded

Food Science and Industries

Committee Chair(s)

Carl A. Ernstrom

Committee

Carl A. Ernstrom

Committee

Dee R. Morgan

Committee

Lewis W. Jones

Abstract

Test procedures were developed for measuring the residual milk clotting activity of a protease produced by Endothia parasitica in curd and whey separated from freshly coagulated milk. A substrate was prepared by reconstituting 6 g low heat nonfat dry milk in 500 ml buffer containing 50 ml 0.5M cacodylic acid, 50 ml 0.2M CaCl2 , 30 ml 0.2M triethanolamine and 370 ml double distilled water. The substrate was stored at 2 to 4 C for 20 hours before use. Two milliliters of whey or supernatant from centrifuged curd-water slurries were inoculated into 25 ml of substrate at 30 C and the coagulation time noted, and compared with that produced by a known dilution of a standard enzyme solution.

Endothia parasitica curd formed at pH 6.7 contained 45 per cent of the enzyme activity added to 454 g milk but when formed at pH 5.2 the curd contained only 25 per cent.

The recovery of Endothia parasitica protease in curd was made by preparing a 1:5 curd-water slurry, adjusting to pH 5.4, filtering and testing the filterate.

Checksum

064b57a1876d8411c19ec86604b91ab6

Included in

Nutrition Commons

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