Optimization Of Grape Seed Oil Production Process And Its Microencapsulation

Grape seed is the waste of grape breweries,which would cause environmental pollution and economic losses.While grape seed is potential source for production of high-quality oil.With the pursuit of high-quality edible oil and the development of cosmetics,the waste utilization of grape seed has become a hot research topic.However,the extraction process of grape seed oil still needs to be optimized,and the further processing,storage and transportation of grape seed oil still need to be discussed.Therefore,in order to develop the waste utilization of grape seed,the production,processing,storage and transportation of grape seed oil have theoretical basis and practical significance.In this paper,supercritical CO2 extraction technology was used to optimize the extraction process of oil from grape seed which was the waste of grape breweries.The effects of heat treatment on the quality of grape seed oil were studied,and the microencapsulation and shelf life of grape seed oil were also investigated.The main research results include the following three aspects:(1)The technological parameters of supercritical CO2 extraction of grape seed oil were optimized by single factor screening and response surface analysis.The results showed that the optimal extraction temperature was 45?,the optimal extraction pressure was 31.52 Mpa,and the optimal static extraction time was 120 min,which yield corresponding to 14.92%.Compared with the current research,the yield of grape seed oil was improved.(2)The effect of heat treatment on the quality of grape seed oil was studied.The results showed that after heat treatment(including boiling and roasting),the peroxide value,iodine value and acid value of grape seed oil did not change significantly,and they all meets the national standards.After boiling and baking,the grape seed oil still had certain antioxidant capacity(DPPH and ABTS).Within the concentration range of grape seed oil(10-50 mg/mL),the antioxidant activity increased with the increase of sample concentration,and the roasted grape seed oil has the stronger antioxidant activity than the baked grape seed oil.The main fatty acid component of grape seed oil was unsaturated fatty acid,the highest content one is linoleic acid,followed by oleic acid and palmitic acid.After boiling and baking,the content of unsaturated fatty acids in grape seed oil increased significantly from 66.66%to 90.07%and 91.76%,respectively.The content of saturated fatty acids also increased from 6.41%to 9.93%and 10.34%respectively.However,heat treatment lead to decrease of total phenols in grape seed oil,which specific reasons need further study and verification.(3)To explore the encapsulation technology of grape seed oil microcapsules.The results showed that good embedding rate(above 85%)and characteristic indexes were obtained by using the wall materials of maltodextrin and soybean protein isolate,Arabic gum and modified starch respectively,the effect of embedding with maltodextrin and soybean protein isolate was the best;after microencapsulation,the peroxide value of grape seed oil decreased significantly.It can be concluded that microencapsulation of grape seed oil can delay oxidation and increase the storage period of grape seed oil.