| The phospholipids are important biological active substances. It can prevent and treat high cholesterol and hyperlipidemia. Also have health enhancingeffects such asanti-oxidatants, anti-aging and so on. The phospholipids contains a hydrophilic group and hydrophobic group-akind of typical amphoteric compound, which has good emulsifying property. Currently, it has been widely used in terms offood, medicine and health care products.In this study, ultrasonic extraction was used to extract the phospholipidsfrom mackerel brains. Phospholipids and sorbitol trioleate was mixed into palm oil as additive to study the isothermal crystallization kinetics.Results are as follows:1?Extraction factors of ultrasonic method were optimized by single factor experiment and orthogonal experiment. The optimal conditions were as follows:extraction solvent is95%ethanol; solid-liquid ratio of raw materials and solvent is1:9;ultrasonic power is300W; time is30min; temperature is35?; ultrasonicextraction should be done twice.2?Phospholipids fatty acids composition of mackerel brain was determined by gas chromatography,which contains high unsaturated fatty acid, such as17.9%DHA and2.7%EPA.3?Differential scanning calorimetry was used to analyze the isothermal crystallization process of palm oil. Because Avrami model is only applied to one single crystallization peak, so the optimal conditions for isothermal crystallization were as follows?cooling rate is3k/min, crystallization temperature is6,8?, heating rate is10k/min.4?Differential scanning calorimetry was used to analyze the influence of additives on isothermal crystallization process of palm oil. The result was that phospholipids can promote the crystallization of palm oil.Crystallization rate K increase, and the half time of crystallization t1/2decrease; span85can hinder the crystallization of palm oil.Crystallization rate K decrease, and the half time of crystallization t1/2increase; the blend of Span85and phospholipidcanhinder the crystallization of palm oil, the crystallization rate K decreases, andthe half time of crystallization t1/2increase.5?Nuclear magnetic resonance was used to analyze of the influence of additives on isothermal crystallization process of palm oil. The result was that span85can hinder the crystallization of palm oil.Crystallization rate K decrease, and the half time of crystallization t1/2increase6?Polarized light microscopy was used to analyze of the influence of additives on crystalline form of palm oil. The result is that span85reduce the number of crystallization, and palm oil samples crystallization is smaller. |
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