Abstract
The molecular distillation of marine oils has been studied in order to prepare edible oils, acid the distilled oil was found rather unstable because of the presence of higher unsaturated fatty acids. The author had previously evaluated the effect of thermal polymerization, in preliminary before the distillation, of whale oil on the stability. This paper deals the results of purification of distilled oil obtained from thermally polymerized whale oil. And further, the author could confirm an antioxidation effect of unsaponifiable matter from soybean oil against oxidation of whale oils, purified, distilled or hydrogenated.
Crude whale oil was polymerized at 260°C in the presence of active earth under nitrogen atmosphere, followed by molecular distillation. The distilled oil was refined, bleached, and deodorized as usual. The stability test of each oil by the A.O.M. accelerating method disclosed that the change of A.U.M. stability was 10.5 hr for thermally polymerized oil, 4.0 hr for the distilled oil, and 9.0 hr for the purified oil as contrasted to 3.3 hr of the original whale oil (Table-3).
Unsaponifiable matter recovered from the distillate of soybean oil deodorization was added to the purified or hydrogenated whale oils and its antioxidative ability was determined. It was observed hat the unsaponifiable matter had great antioxidative effect against the oxidation of hydrogenated whale oil and that optimum concentration was 0.8 % (Fig.-4). Then 0.8 % of unsaponifiable matter was added to the above mentioned purified distilled oil and it was ascertained that the addition of unsaponifiable matter greatly improved its stability. The A.U, M. stability of purified, distilled oil from thermally polymerized whale oil was over 200 hr when it was incorporated with soybean unsaponifiable (Fig.-5).
