Study On Extraction Of Sweet Pepper Seed Oil By Subcritical Temperature And Its Mechanism

China's pepper cultivation area is extensive,the annual output ranks first in the world.At present,the development and utilization of pepper at home and abroad mainly focus on chili food processing,pepper extract by-products(pepper pigment,pepper essence,capsaicin)and other products.However chopsticks accounted for more than 40% of dry pepper seeds did not get a reasonable development and utilization.A large number of studies have shown that pepper seeds are complex in the composition,which is rich in oil,crude fiber,protein and various vitamins and other nutrients,is a high value of the development of nutrients.Subcritical extraction techniques(such as propane and butane)are one of the most popular techniques.Due to its low extraction pressure and high fat yield,it overcomes the drawbacks of supercritical carbon dioxide extraction.In this study,the effects of subcritical propane on the extraction of pepper seed oil were studied.The main contents of this study are as follows.First,the degree of reaction of the Maillard reaction was determined by the change of reactants,intermediates,final products and side reactions in the process of frying pepper seed.The results showed that the content of reducing sugar and amino acid as reactants of Mail ard reaction showed a decreasing trend with the increase of temperature and time.At the same time,due to the presence of polysacchar ide degradation reaction,the content of reducing sugar in a certain range of a slight increase in the range.The content of hydroxymethylfurfural with the Maillard reaction showed a trend of increasing first and then decreasing.At pyrolysis temperatures of 200 °C,the pyrazine and pyrrole compounds that represent roasted aroma substances are increasing.In this experiment,the chilli seeds were fried at 160 °C for 20 min by Maillard reaction,and the next experiment was carried out.Secondly,the subcritical propane extraction of Luzhou pepper seed oil was dynamically monitored.The extraction rate,physical and chemical indexes,fatty acid,vitamin E and thermal stability of pepper seed oil obtained by each time period were determined by dividing the extraction time into five stages.And then compare the similarities and differences between these data of pepper seed oil in each time period,and to provide theoretical basis for subcritical extraction of pepper seed oil.The results showed that the content of linoleic acid in unsaturated fatty acids was more than 70%,and the two fatty acids were composed of palmitic acid,oleic acid and linoleic acid.During the different time periods of dynamic monitoring,the change of vitamin E content was obvious,and the shortening time of extraction to 9 min had little effect on the content of vitamin E in oil.Oil in the active ingredients in the period of time changes occur,we can shorten the extraction time of oil for 9 min.This will not only guarantee the oil out of oil,but the effect of each active ingredient in the oil is smal,you can get the quality of the hot pepper seed oil.Finally,this study will focus on the residual solvent propane in pepper seed oil,and use low temperature ultrasound method for desolvation.The capsaica oil and the original pepper seed oil were analyzed by headspace-solid phase microextraction(HSSPME)combined with gas chromatography-mass spectrometry(GC-MS),and view the desolvation effect and improve the desolvation protocol.The results show that the high temperature of 60 °C,low power 50 W,long 30 min,is the best condition for oil and ultrasonic desolvation.Under these conditions,by adding a certain percentage of fried pepper seed powder to the pepper seed oil,and then through the ultrasonic treatment,can further achieve the purpose of removing the residual solvent.At the same time,it can be a greater degree of compensation for pepper seed oil due to ultrasonic treatment and loss of aroma components.