Optimization The Extraction Parameters Of Garlic Oil And Estimation The Possibility Of Using Garlic Oil As Antioxidant For Eatable Oil

The main active substances of garlic oil are organic sulfur compounds such as alliin,allicin,ajoene,and diallyl sulfide,which have been proved to have anti-oxidant,antibacterial and anti-tumor effects.The objective of this study is to use ultrasonic treatment,microwave treatment,exogenous cellulase and pectinase to promote the release of garlic oil from bulb cells.Microwave-assisted extraction of garlic essential oil has the advantages of high extraction speed,high efficiency and low energy consumption,but its operation safety in solvent is a concern.Ultrasonic-assisted extraction of garlic oil is one of the most simple and economical extraction methods.The enzymatic hydrolysis of endogenous alliinase in garlic has a significant effect on the composition and antioxidant activity of garlic oil.The effects of alliinase digestion time on the composition of the garlic essential oil and its antioxidant activity were studied.This paper also investigated the effect of adding L-selenylmethylselenocysteine on the composition of the garlic essential oil and its antioxidant activity in the process of garlic allergen-dominated alliinase digestion.The chemical composition of the garlic essential oil obtained under different extraction conditions and its use as an antioxidant in edible oils and fats were studied.It could provide a new type of edible oil natural antioxidant additive that combines functional and antioxidant properties.The main conclusions of the study include:1.According to the results from the experimental study with the orthogonal experiment design on the microwave-assisted extraction under room temperature,the order of the effects of different processing parameters on the extraction efficiency was as follows: liquid-to-material ratio > microwave power > microwave processing time > mass fraction of acetone.The highest yield of garlic oil was 2.62 % under the conditions of acetone mass fraction of 90 %,liquid to material ratio of 1:25,microwave time of 60 s and microwave power of 100 w.The maximum allyl trisulfide content is up to 47.06 %.In addition to diallyl trisulfide,the garlic oil sample extracted with microwave-assisted extraction also contained diallyl disulfide,3-vinyl-1,2-dithia-4-cyclohexene,3-vinyl-1,2-dithia-5-cyclohexene,1-oxa-4,6-diazacyclooctane-5-thione,and(methylthio)acetonitrile,etc.The microwave-assisted extraction of garlic oil has the characteristics of high extraction speed,high efficiency and low energy consumption.However,due to the microwave radiation conditions,the operation of solvent extraction presents a large potential safety hazards,therefore,we also carry out the research on ultrasonic assisted garlic oil extraction process.2.According to the results from the experimental study with orthogonal experiment of ultrasonic-assisted extraction,the order of effects of different processing parameters on the extraction efficiency was as foolows: ultrasonic power >ultrasonic processing time > enzymolysis > mass fraction of acetone.The aforementioned parameters all presented dominant effect on the extraction efficiency.The highest yield of the garlic oil was 1.16 % under the extraction temperature of40 ?,the liquid-to-material ratio of 1:8,the ultrasonic treatment time of 45 min,and ultrasonic power of 180 W / L.The highest active substance(diallyl trisulfide)mass fraction reached 41.48 %.In addition to diallyl trisulfide,the sample obtained by ultrasonic extraction also contained diallyl disulfide,diallyl disulfide,3-vinyl-1,2-dithia-4-ring alkenyl,3-vinyl-1,2-dithia-5-cyclohexene,1-oxa-4,6-diazacyclooctane-5-thione,and other related antioxidant substances.The ultrasonic extraction method is convenient for large-scale production,and the equipment requirements are not high,which could potentially be commercialized for the garlic oil production.It was proved that ultrasonic assisted extraction of garlic oil was one of the most simple and economical extraction methods,and it also had the potential to further increase the extraction rate.3.The effect of enzymatic reaction of endogenous alliinase on the composition and antioxidant activity of garlic oil was also investigated.The results indicated that alliinase was a key enzyme for the conversion of alliin to different sulfur-containing compounds.The enzymatic reaction time had an impact on the quality of garlic oil.In a certain range(? 5 h),longer enzymatic reaction time of alliin favored higher production of diallyl trisulfide,the main active ingredient in garlic essential oil.The proportion of diallyl trisulfide accounted for 41.32 % when the enzymatic reaction was carried out for 5 h.The highest content of total antioxidants in the garlic oil wasobtained after 3 h of alliinase enzymatic reaction.Correspondingly,the higher the content of total antioxidants in garlic essential oil,the stronger ability to prolong the oxidation induction time of Camellia oleifera.When the amount of garlic essential oil reached 10%,the antioxidant stability of Camellia oleoresin was equivalent to that of TBHQ added by the national standard of 0.02 %,and the corresponding shelf life prediction of camellia oil reached an average of 4584 h.4.During the enzymatic reaction of alliinase,the garlic oil obtained by the addition of L-selenosemethylselenocysteine prior to the alliinase enzymatic reaction,and the selenium content in garlic essential oil was up to 8.4mg/kg detected by HG-AFS.It was preliminary proved that the alliinase enzymatic reaction process could integrate the selenium element in the externally added L-selenylmethylselenocysteine into the organic components of the garlic essential oil.When the adding amount of garlic oil was 5 %,the average oxidation induction time of the essential oil of garlic oil containing seleno-containing sulfur compounds was3109 hours,and the average oxidation induction time of common garlic oil to camellia oil was 2311 hours,which was significantly shorter than the former.