Physicochemical Properties, Crystallization Behavior and Oxidative Stabilities of Enzymatic Interesterified Fats of Beef Tallow, Palm Stearin and Camellia Oil Blends

Properties, crystallization behavior and oxidative stabilities of enzymatically catalyzed interesterified fats were investigated in this study. Interesterified fats were catalyzed by Lipase Lipozyme RM IM, through reaction from beef tallow (BT), palm stearin (PS) and camellia oil (CO)under the mass ratio of 7.55: 2.45: 4 (BT: CO: PS) using 3.65% (w/w) of Lipozyme RM IM at 72.6°C for 3.85 h. After reaction, interesterified fats with 36.8°C sliding melting point (SMP) was obtained. Physicochemical properties (fatty acid profile, triacylglycerol profile, solid fat content (SFC), melting and crystallization curve, polymorphic forms) of interesterified fats were characterized. Results proved that interesterified fats blends after interesterification were improved with desirable β' type crystals and preferable SFC. Triacylglycerol constituent of interesterified fats displayed a decrease in OOO, PSS/SPS, LLL, SSS and increased in PSO/POS/SPO, POO/OPO, POP/PPO, PLO/PLP/PPL by comparison of physical blends without interesterification. Additionally, it is estimated that interesterified fats have a moderate antioxidative stability about 352 days-shelf life at 20°C through the traditional accelerated oxidation test. In conclusion, interesterified fats with desirable properties could be suitable for plastic fats use.