Study On Soy Sauce Brewing With Citrus Peel Inoculated With Double Strain

Soy sauce was made from koji,contains various enzyme produced by microbial,which was preparation though a long period of fermentation,and the protein and starch raw materials are hydrolyzed into a variety of molecules and sugars.These substances contributed to the formation of the seasoning soy sauce,which has excellent functional activity and unique flavor.The use of double strains to brew soy sauce has become a research hotspot.However,most studies have focused on improve the utilization of raw materials and enhance the taste,flavor and color of soy sauce,while ignoring the functional activity of soy sauce.In this paper,we intvestigated that the effect of citrus peel on the changs of antioxidant activity in the process of brewing soy sauc and the quality of raw soy sauce.The main contents were as follows:1.Screening of Aspergillus niger HG-35 by our laboratory(the mold has a strong ability to produce acid protease,cellulase,pectinase,and ?-glucosidase)coupled with Aspergillus oryzae(Huniang 3.042)koji making.We studied that the changes of moisture content and enzyme activities during the process of koji-making,and discussed that the changs of the quality indexes,color and antioxidant activity during the process of moromi fermentation.The results showed that the optimum koji-making conditions were as follows: the ratio of Aspergillus oryzae and Aspergillus niger was 3,the inoculation amount was 0.3%(w/w),the ratio of soybean to flour was 7: 3.There was no significant difference in the moisture cotent and the activities of ?-amylase and neutral protease,compared with the control group(koji prepared with Aspergillus oryzae),the activities of acid protease,cellulase,pectinase and ?-glucosidase were increased by 57%,63%,68% and 107%,respectively.Soy sauce prepared by the above process,which the quality indexes were improved and the contents of total flavonoids,total polyphenols,isoflavone aglycones and antioxidant capacity were significantly improved at the 120 days of fermentation,compared with the control group.Finally,soy sauce prepared with double strains koji can improve the quality and antioxidant activity,which also can increase the health benefits of soy sauce.2.Citrus peel contains a variety of nutrients and functional ingredients.Soy sauce prepared with koji that contains the powder of citrus peel,which optimized the processof the koji-making.We investigated that the effects of citrus peel on the quality index,color,antioxidant,antioxidant and flavor of soy sauce.The results showed that the optimum conditions were as follows:the adding amount of orange power was 10%,the ratio of Aspergillus oryzae and Aspergillus niger was 3 and the time of koji-making was44 h.,and the time was 44 h.Under the condition,the relative error of the theoretical value was only 0.5%.There was no significant difference in the moisture content and the activities of cellulase,pectinase and ?-amylase in the koji with citrus peel,compared with the control group.But,the biomass and neutral protease were 22% and 13% lower than that of the control group,and the acidities of acid protease and ?-glucosidase increased by 12% and 45% compared with the control group.In the 120 days of morimo fermentation of soy sauce,while the total acid content increased by 24%,compared with the control group,there were no significant difference in other quality indicators.However,the contents of total amino acids,essential amino acids and antioxidants were significantly higher than those of the control group,and the color was significantly lighter than that of the control group,and the flavor substances increased by 26.To sum up,soy sauce prepared with citrus peel can not only enhance the quality,color,flavor and the functional activity,but also to avoid waste of resources and increase the added value of citrus peel.