Study On The Extraction Of Soy Sauce Fermentation Base Material And Lipase Catalyzed Synthesis Of 1,3-Diacylglycerol From Its Oil

Soy sauce fermentation base material?also named soy sauce residues?are the main by-products of soy sauce fermentation.They are dark brown and the annual yield is enormous,according to statistics,just in Guangdong Province,its yield have more than 150tons per year.In addition,a large amount of valuable components,such as oil,fibers,and isoflavones,were remained in soy sauce fermentation base material.Thus,soy sauce residues have a high recycling value.However,the chemical structures of soybeans were altered after soy sauce fermentation.Such as,the oil residue is tightly combined with fiber and it has occurred O xidation.This process results in the difficult oil removal,thereby restricting these residues utilization.At present,soy sauce fermentation base material is mainly disposed of in a simple and low value-added way,such as as fertilizer or feed,or even buried directly.This will cause environmental pollution and the formation of a great waste of resources.Based on these problems,this paper use a novel extraction technology to realize the comprehensive utilization of soy sauce fermentation base material.At the same time,enzymatic deacidification technology have been used for oil oil deacidification treatment.Through the research to improve resource utilization,and dispose the problem of the soy sauce fermentation makings the harm to the environment.The main research contents and results are as follows:?1?Basic composition analysis.Compared to the three domestic soy sauce production company's soy sauce fermentation base material quality,from the component:moisture,crude oil,protein,dietary fiber and ash.The contet of moisture and salt content of the soy sauce fermentation makings from the company C were the highest?51.42%and 25.71%,respectively?.Company B's soy sauce fermentation makings have most abundant oil,accounting for 38.43%,The basic composition contents of soy sauce fermentation makings from Company A were 36.50±0.31%moisture,33.22±0.38%crude oil,16.71±0.07%protein,23.13±0.71%dietary fiber and 15.41±0.42%ash.Comprehensive oil,protein,fiber three active ingredients of the re-use,Company A's soy sauce fermentation base material is chosen as the main research materials.?2?Extraction and refining of soy sauce fermentation base oil.Based on the best process of extracting oil by the continuous phase transition extraction under low temperature,compared with the traditional extraction method.The Experiment result expresses that the yield of low temperature continuous phase change extraction?with butane as solvent?was about 3%higher than that of the former,and the extraction time was short?only 45 min?,the extraction temperature was 45?carried out,to avoid further high temperature deterioration of the grease.By comparing achieve rate of oil in the three kinds of solvent extraction,the results showed that directly use butane extraction effect is best?wet base gain rate up to 19.46%?,and the moisture and volatile matter,insoluble impurities,POV,iodine value,SV and other indicators are basically within the national standard,but the acid value of 123 mg KOH/g seriously exceeded.Then,compared the effect of four kinds of acid method?directly add and subtract,ethanol extraction,molecular distillation,enzymatic deacidification?,found that enzymatic esterification deacidification,not only will not cause loss of grease,and mild reaction,more suitable for sauce residue oil with high acid value of acid.For example,under the immobilized lipase RM IM catalytic,only need 11 h reaction,sauce residue extraction oil acid value can be decreased from121.38 mg KOH/g to 3.47 mg KOH/g,a drop of 97.14%.?3?Isoflavone extraction and content analysis.soy sauce fermentation makings of soybean isoflavone is mainly still remain in the scum,containing four four kinds of soy isoflavones,such as genistin,daidzein,glycitein,genistein,the four kinds of soybean isoflavones.Compared with not fermented soybean,less daidzein,glycitin two components;but the total amount of soybean isoflavones in soy sa uce fermentation makings is 0.3586%,which was 2.62 times of that of the unfermented soybean.Soybean isoflavones can be achieved by using low temperature continuous phase change and ethanol as solvent.Such as,with 95%ethanol,extraction 2 h,the extraction yield can reach 96.02%.?4?HEMF of soy sauce fermentation base material extraction and content analysis.Results show that there were two forms of HEMF(5-ethyl-4-hydroxy-2-methyl-3?2H?-furanone in the soy souce residues oil extracted with continuous phase transition extraction under low temperature technology,and the total content of 242.25 ppm.?5?Immobilization of highly esterified active lipase.With immobilized rate and the recovery rate of enzyme activity as an index,through the single factor experiment,finally got the best immobilization process conditions:Macroporous resin A,0.075 M pH 7.5 of buffer,resin addition ratio=1:1.3,immobilization temperature 30?,adsorption time 4h.Through the above conditions of Immobilized Lipase Esterification 00S vitality of 865.12U/g,immobilization rate was 94.32%,and the esterification rate was up to 57.04%at 2 h.The optimum temperature of lipase was increased from 40?to 65?,and the esterification activity was increased by 30%.after repeated use 10 times still have 91.56%of the initial enzyme activity,have a good operation stability.?6?The application study in the synthesis of 1,3-DG for the fermentation of sauce residue oil by the immobilized enzyme 00S.Experimental results show that the amount of enzyme added,the amount of glycerol added,the reaction temperature,the reaction time and the auxiliary dehydration method of the reaction system had an effect on the self-made immobilized lipase 00S catalytic esterification rate.When the amount of glycerol added is equal to 1.2 times the free fatty acid formation of the diglyceride,the reaction temperature of 65?,the amount of lipase added 1%,the reaction side of the vacuum side by side when the nitrogen,the fastest esterification rate.Moreover,different metal ions have different effects on immobilized lipase 00S,at the concentration of 2 mmol/L,Ca²⁺,K⁺,Ba²⁺,Mg²⁺showed activation,and the best effect in K⁺activation deacidification rate can reach 70.35%?2h?;Zn²⁺,Mn²⁺,Fe²⁺showed inhibitory effect,among them with Fe²⁺the strongest inhibitory effect.Analysis of the product after esterification reaction,found that enzymatic esterification reaction will not change the composition of lipids,fat acid before and after the acid residue of fat and oil composition in the range of soybean oil GB;The contents of glycerol ester in the deacidified oil were 39.05%1,3-DG,5.00%1,2-DG,9.31%MG,2.24%FFA.