Preparation Of Prickly Ash Seed Oil And Purification Of ?-Linolenic Acid

Sichuan has already reached the first place in China's prickly ash planting industry,which has become one of the important industries in the economic development of Sichuan Province.Prickly ash seed is a by-product of prickly ash seasoning,which contains high functional oil and is a good new oil resource,but a large number of prickly ash seed is wasted every year.Therefore,it is of great significance for the sustainable development of Zanthoxylum industry to develop Zanthoxylum seeds with advanced technology.In this paper,the extraction technology,physicochemical properties,main fatty acid content,refining of zanthoxylum seed oil and the separation and purification of?-linolenic acid in the oil were studied.The specific results are as follows:?1?The extraction process of zanthoxylum seed oil was studied by using supercritical CO₂.The extraction rate and the content of?-linolenic acid in zanthoxylum seed oil were taken as the index.The extraction process of zanthoxylum prickly ash seed oil was optimized synchronously by response surface on the basis of single factor experiment.It can be seen from the analysis that the influence factors of this process on the extraction rate of zanthoxylum seed are:extraction temperature>extraction pressure>extraction time,and the influence factors on the content of?-linolenic acid in zanthoxylum seed oil are:extraction pressure>extraction temperature>extraction time.Through the simultaneous optimization,the optimum conditions were obtained as follows:extraction pressure 30 MPa,extraction temperature 51?,extraction time 90 min.Under this condition,the extraction of supercritical CO₂ was carried out,and the oil extraction rate of zanthoxylum seeds was 12.52%on average,and the?-linolenic acid content was 4.45%on average.By using response surface synchronous optimization method to simulate,the oil extraction rate and the?-linolenic acid content of Zanthoxylum prickly ash seeds were simulated by response surface synchronous optimization method.?2?The quality characteristics of zanthoxylum seed oil extracted by supercritical CO₂ were compared with that extracted by traditional solvent.Supercritical CO₂ extraction of zanthoxylum oil has rich Zanthoxylum flavor but no peculiar smell,with 12.52%of extraction rate,4.45%of?-linolenic acid content,0.52 g/100g of water content,18.8?KOH?mg/g of acid value,16 mmol/kg of peroxide value,198 mg/g of saponification value,0.36%of unsaponifiable matter.Accoreding to that extracted by traditional solvent,the extraction rate was 9.23%,the?-linolenic acid content was 3.69%,the water content was 0.82 g/100g,the acid value was 22.1?KOH?mg/g,the peroxide value was 20 mmol/kg,the saponification value was 193 mg/g,the unsaponifiable matter was 0.48%.As for the oil extraction rate,Supercritical CO₂ extraction is much higher than solvent extraction.And supercritical CO₂ extraction is better in the accumulation of unsaturated fatty acids for zanthoxylum seed oil,the quality of oil extracted is higher as well.?3?The refining process of zanthoxylum seed oil was studied.Degumming process was adopted at 30?,adding 85%phosphoric acid 0.25%and water 5%for 20 min;alkali refining deacidification process was adopted at 80?,with super alkali conten 0.15%,NaOH concentration 10%,and time 30 min;The decolorization process was adopted at 100?,with decolorization dose of 5%,activated carbon:activated clay=1:8,time 25 min,the degumming rate of 95.5%,deacidification rate of 89.8%,decolorization rate of 95.5%,decolorization rate of 97.1%.This technology has no great influence on the fatty acid composition and content of zanthoxylum seed oil,and the quality index of zanthoxylum seed oil meets the requirements of national standards.?4?Taking the content of?–linolenic for the reference index,the extraction of Zanthoxylumbungeanum seed oil by ultrasound microwave assisted with?-cyclodextrin inclusion using supercritical CO₂ was studied.And the orthogonal test was carried out on the basis of single factor.According to the analysis of orthogonal test table,the primary and secondary factors influencing the process of ultrasound-microwave synergistic?-cyclodextrin inclusion of?-linolenic acid are:?mixed fatty acid+anhydrous ethanol?:?-cyclodextrin and ultrasonic power have the greatest influence,the inclusion time is the second,and the microwave power is the least;according to the analysis of variance of orthogonal test table,?mixed fatty acid+anhydrous ethanol?:?-cyclodextrin has the least influence on ultrasonic power.The process of?-linolenic acid inclusion with?-cyclodextrin by microwave has significant effect,but the effect of microwave power,ultrasonic power and inclusion time is not significant.The results of orthogonal test showed that the optimum conditions were as follows:?mixed fatty acid+anhydrous ethanol?:?-cyclodextrin=1:10?g/g?,microwave power 200 W,ultrasonic power 250 W,and inclusion time 30 min to get the content of?-linolenic acid 22.56%.