Copper-Hydrogenated Soybean and Linseed Oils: Composition, Organoleptic Quality and Oxidative Stability'

Copper and nickel hydrogenations give a wide distribution of double bonds in the monoene fraction from both reduced soybean and linseed oils. With copper catalysts, high pressure hydrogenation reduces the extent of this double bond distribution when compared with low pressure hydrogenation. With nickel catalysts, some t.17-octadecenoate is formed but less than with a copper catalyst. In room odor evaluations, copper-hydrogenated soybean (CuHSB) oil gave higher scores and lower fishy responses than nickel-hydrogenated soybean oil after both had been exposed to fluorescent light. A mixture of CuHSB oil (33%) and peanut oil received room odor scores equal to or better than peanut oil alone, whether light exposed or not. Although hydrogenated products with remarkable stability to oxidation were obtained by copper hydrogenation of linseed oil, these oils have lower organoleptic stability when compared to nickel-hydrogenated, winterized soybean oil.