Research And Process Design Of Sesame Oil Production By Enzymatic Assisted Water-substitution Method

Sesame is one of the most important oil crops in China which has a long history of cultivation. Sesame oil has high value on nutrition and was rich of polyunsaturated fatty acids in the human body. Sesame oil was loved by both domestic and foreign consumers for its unique flavor and texture, most production methods of sesame oil was water-generation method. Water-generation method was the traditional method in our country, it has many advantages such as mild operating conditions, natural and green product, and simple equipment et.al.But the oil extraction rate of water-substitution method was lower, the oil residual rate and moisture content in the slag was higher, these disadvantages restrict the generation of large-scale production of water-substitution method.With the continuous development of enzyme technology, enzymes are increasingly being used in the process of oil production. Enzyme can hydrolyze many molecules such as cellulose,proteins and destroy the cell structure,this is conducive to water penetration and oil extraction, and then improve the oil extraction rate and reduce the oil residual rate in the slag.Enzymatic processes was added on the basis of traditional water-substitution method in this paper, water-substitution method by enzymatic assisting to product sesame oil. Oil extraction and residual rate was comprehensive survey indicators to study the effect of different kinds of enzymes,the results showed that:acid protease and bromelain has light impact on sesame oil extraction, cellulase, protease, papain and neutral protease has greater impact on the sesame oil extraction, The sort of these four enzymes was alkaline protease> cellulase> papain> neutral protease. Study the compounding effect of these four enzyme using orthogonal test on the basis of former experiments, the optimal condition of the amount of enzymes was obtained:cellulase200U/g, alkaline protease2000U/g, papain3500U/g, neutral protease3000U/g.Thus, preparation in the traditional water-generation method by adding enzyme can effectively improve the oil extraction rate and reduce the oil residual rate in the sesame slag.Oil extraction and residual rate was comprehensive survey indicators to study the optimal conditions in the enzymatic processes on the basis of the best combination of the enzyme amount,and the optimal conditions were pH6.0, temperature50℃, time 3.0h.The oil extraction rate was89.55%and the oil residual rate was6.73%under the optimal conditions.The acid value of obtained sesame oil was1.36mgKOH/g, peroxide value was0.89mmol/kg, saponification value was188.9mg/g, iodine value was102.18, the color was Y23.0R11.8, moisture and volatile matter content was0.25%. The analysis of fatty acid composition of sesame oil by gas chromatography showed that oil prepared by water-substitution method by enzymatic assisting has a high content of unsaturated fatty acids, the main ingredient of it were oleic and linoleic acid,and the content of them were39.72%and43.50%.Its saturated fatty acids were palmitic acid, stearic acid, arachidic acid, and linolenic acid,the content of them were9.46%,5.81%,0.55%and0.32%.In addition, the sesame oil has a small amount of trans fatty acids due to the high temperatures fring sesame seeds, and the content of elaidic was0.12%,the content of anti-linoleic acid was0.20%.Finally, this paper conducted the process design of water-substitution method by enzymatic assisting according to the conditions by the former study.Sesame was fried at200℃for15～20min, added80%water twice after refined and churned against the pulp,and then digested in the best conditions. After this, separated the oil and wet sesame dregs using three-phase centrifuge. Then, choose the right equipment according to the design calculations, design the workshop and complete the related drawings.