Winterization

Abstract: The fungal oil extracted fromMortierella ramanniana var.angulispora (IFO 8187) was solvent winterized in order to raise the content of γ-linolenic acid (GLA). Effects of winterization conditions (solvent, oil concentration in the solvent and temperature) and changes of glyceride compositions were discussed. The fungal oil was separated into four diglycerides and 17 triglycerides (TG) with high performance liquid chromatography. The predominant species were POO, POP and LOP, whose contents were 24.4, 22.9 and 9.4% of the total TG, respectively. Ethanol at 4°C gave the highest GLA content of 10.5% in spite of lower yield than with acetone at −20°C. The highest separation efficiency for GLA (ηGLA) was 0.27 with acetone at −20°C and 10% oil concentration, resulting in 8.3% of GLA from the fungal oil at 5.7% LGA. In case of lower oil concentration at 5–20%, ηGLA showed higher in the following order: acetone (−20°C)>n-hexane (−20°C)>acetone (4°C)>petroleum ether (−20°C). The winterization process also proved to be effective for the separation of TG type, Sa2U (Sa; saturated fatty acid; U, unsaturated fatty acid) into the crystallized fraction and SaU2 into the liquid fraction. Acetone at −20°C showed higher separation efficiency for triunsaturated TG than the other solvents.

Abstract: Soybean oil is processed for a variety of food uses, salad/cooking oil, margarine and shortening. Crude soybean oil is composed mainly of triglycerides but also contains measurable amounts of minor constituents that may have beneficial or detrimental effects on oil characteristics. The nature of these minor constituents, the role they play in oil stability or deterioration and their fate during processing are subjects of this review. Iodine value, fatty acid composition, solid fat index and congeal point are chemical and physical characteristics of oil that are affected by the hydrogenation process. Techniques and effects of degumming, alkali refining, bleaching, hydrogenation, winterization and deodorization are discussed. Utilization or disposal of by-products or wastes from each processing step is reviewed.

Abstract: A substantially odorless, refined fish oil product containing more than 20% eicosapentaenoic acid as the fatty acid residue is provided. The product is produced by a process comprising combinations of steps of winterization of the oil, interesterification of the oil, deodorization procedure of the oil by heating thereof in vacuo with polyhydric alcohol and monoglyceride, and molecular distillation after the deodorization procedure. The product can be used mainly for prevention and therapy of thrombotic maladies by controlling the content of cholesterol in blood in humans.