抄録
During the preservation of sardine meal and the dried flesh of fish, their colour changes to dark brown. Though it is clearly due to the presence of fish oil, such a remarkable change in colour is not observable in the case of preservation of the oil obtained by pressing the boiled sardine in the process of manufacturing the sardine cake. Such oil, being depot fat, differs in property from the oil extracted by ether from the sardine cake, which is, as reported previously, the tissue fat mixed with depot fat. Whether the presence of tissue fat or the difference in chemical properties of the adsorbent adsorbing the oil may cause the colour change, is yet unknown. In the present study, the sardine oil and the sardine-meal-oil were adsorbed with various adsorbents, defatted sardine meal, defatted casein, defatted kaolin and defatted dextrin, and after having been preserved for 30 days, were extracted by ether and examined, with the result that the protein or the proteinous substances as adsorbent have a great bearing to the change of colour of the fish oil.