Nutritional and physiological effects of casein modified by glucose, diacetyl, or hexanal

Casein was modified by glucose, diacetyl, or hexanal at 50 degrees C, RH 75% for 1, 7, or 11 days. The chemical changes and digestibility in vitro of these nondialyzable caseins were investigated. The effects of these nondialyzable caseins supplemented with lost amino acids, on rats were studied by pair-feeding for 2 months. It was observed that internal organs such as liver, spleen, kidney, stomach, small intestine, cecum, colon and rectum were mostly unchanged. Biochemical values such as hematocrit, cholesterol, triglyceride, GPT, and GOT were also unchanged. However, the quantity of leucocytes was increased and serum glucose was decreased by feeding rats with modified caseins. Significant decrease in weight gain of rats fed with modified casein was observed, and the rate of decrease depended on the degree of modification of casein by carbonyl compounds. From these results, we supported the suggestion that some inhibitory or antinutritional compounds might be formed during the modification of casein by carbonyl compounds.