抄録
The effect of food additives on tryptic hydrolysis of casein in vitro has been studied. Tryptic activity was commonly determined by the colorimetric method using Folin's reagent. This method, however, was not available in the presence of phenolic compounds. In order to organize a systematic assay by this method, the authors investigated available conditions for gel filtration to separate any obstructive compounds on colorimetry from hydrolyzates of casein. One ml of TCA filtrate containing phenolic compound was placed on Sephadex G-10 column (9×310mm), and elution was carried out with 0.05M NaCl. The first 5 ml of effluent was left out and the next 25 ml collected. This fraction contained all hydrolyzates of casein and no salicylate, no p-OH benzoate, and no ethyl p-OH benzoate. By this gel filtration method, the effects of Na salicylate (10-2M), ethyl p-OH benzoate (10-3M) and Na p-OH benzoate (10-2M), and by the usual method (Anson method), the effects of Na benzoate (10-2M), Na dehydroacetate (10-2M) and Na sorbate (10-2M) on tryptic digestion of casein were investigated. The effects of these additives on tryptic hydrolysis of casein were not found at least by these methods.
