关键词: 凝胶油；蜂蜡-米糠蜡；起酥油；大豆油；协同作用

Abstract: In this study, soybean oil oleogels were developed by using beeswax, rice bran wax or their mixtures (10:0, 9:1, 8:2, 7:3, 6:4, 5:5, 3:7, 1:9, 0:10 m/m) as an oleogelator at concentrations of 5% and 8%, and their physical properties were measured and compared with those of shortening. It was found that the hardness (in the range of 11.9–140.4 g) of oleogels increased first, then decreased, and finally increased slightly with increasing amount of rice bran wax. When the mixing ratio of beeswax and rice bran wax was 8:2, the prepared oleogels had the highest hardness, indicating the synergistic effect of the mixture. Meanwhile, oil separation in oleogels was evaluated by centrifugation. It was found that the oleogels with a low amount of rice bran wax (beeswax : rice bran wax ratio = 5:5) were stable without oil separation. Moreover, oil separation was lower in the oleogels with 8% oleogelator than in shortening. The solid fat content (SFC) of the oleogels (8.5%–4%) was significantly lower than that of shortening (65%–20%) at 10–40 ℃. The melting point of the oleogels (50.2 ℃) measured by differential scanning calorimetry (DSC) was higher than that of shortening (43.1 ℃). The results of X-ray diffraction (XRD) showed the crystalline morphology (β′-type) of the oleogels with 8% beeswax-rice bran wax mixture at an 8:2 ratio was close to that of shortening, both exhibiting fine crystals. It was found that the oleogels provided a good baking performance and resulted in a great reduction in the SFC of baked products and therefore could potentially used to develop healthier products for consumers.

Key words: oleogels; beeswax-rice bran wax mixtures; shortening; soybean oil; synergism