Aqueous Enzymatic Extraction Of Linseed Oil And Its Microencapsulation

The linseed oil includes a mass of unsaturated fatty acid. It has the important physiological function and the extremely high nutritional value. The high content linolenic acid make it attracted people's attention. The present paper studied on the method of aqueous enzymatic extraction for linseed and the microencapsulation of the linseed oil. The appropriate formula of wall material was chosen, the craft conditions were optimized. The storage stability of the linseed oil microcapsule and its quality were researched.The paper first studied the reasonable method of aqueous enzymatic extraction suitable for linseed . The result showed that 82.3% free oil was obtained when the linseed without gel was breaked up without water and hydrolyzed by enzyme concentration 1.5% at 60℃, pH 9.0 for 5 hours with alkaline proteinase, followed by use of the complex cellulase 1.5% at 50℃, pH 5.0 for 5 hours. The concentration of substrate to solution as 1:5 (w/v).Because the linseed oil was extremely easily oxidized, the linseed oil was microencapsulated by spray drying, Various proteins, such as gelatin, whey protein concentrate(WPC), soybean protein isolate(SPI) and HI-CAP 100 were used as the microencapsulating agents of linseed oil. The result showed, the microcapsules with the best storage stability and high microencapsulation efficiency and yield were prepared form gelatin and sucrose based wall materials. After optimizes, the formula of the wall material is: gelatin/sucrose 1: 6, the total solids 20%(w/v), the load amount 35%(w/w).The storage stability of microencapsulate was improved when pullulan and natural antioxidant like tocopherol, ascorbic acid and lecithin were added to the wall materials. After the researching, pullulan 0.6%, tocopherol 0.15%, lecithin 0.5%. The processing parameters (homogenizing pressure, inlet and outlet temperature) which affected the product quality were optimized by orthogonal experiment. Finally, homogenizing pressure 40MPa, inlet temperature 175℃, outlet temperature 75℃were determined.The vitrification transition temperature and the thermal analysis of linseed oil microcapsule were determination. Finally, this product which has the storage stability stores is in the glass condition when under the normal temperature. The microcapsule wall material has the good thermal stability. The oxidizes initial temperature of the linseed oil was elevated after the microencapsuation. The oxidation stability increased obviously.