Ibtesam I. Ahmed, Manal A. Sorour, Mohamed S. Abbas, Amira Sh. Soliman

Abstract

Soybean oil (SO) and fully hydrogenated soybean oil (FH) blends as a trans-free with different ratios 40:60 (F4S6) and 45:55 (F45S55) were prepared as an alternative to partial as alternative to partially hydrogenated for manufacturing shortening, margarine and confectionary . Rheological properties of different samples of soybean oil, partially hydrogenated soybean oil (PH), and the blend of (SO) and (FH) were measured using Brookfield rheometer at different shear rates and temperatures. The results revealed that soybean oil at low temperatures had shear thickening behavior, while at high temperatures exhibited shear thinning behavior. Partially hydrogenated soybean exhibited shear thinning at different temperatures (1, 10, 20, 30, and 40 ℃), and shear thickening at temperatures 50 and 70 ℃. Meanwhile, F4S6 and F45S55 exhibited shear thickening behavior for all temperatures studied. The viscosity decreased with increasing temperature and displayed shear thinning. The activation energy was determined using Arrhenius law. Chemical properties (Peroxide value, Acid value, saponification number, and iodine values) of different samples were determined. The results revealed that the lowest peroxide value was for FH. However, the lowest saponification number and iodine value were for partially PH‎.