Utilization Of High-salt Liquid Soy Sauce Residues

The waste residues of fermented soy sauce,as an abundant and salty byproduct,are hard to preserve and transport.In recent years it has attracted lots of attention home and abroad about their recycle and reuse.However,hardly any noteworthy effects were observed and fewer comprehensive utilization methods were discovered.Therefore,the soy sauce residues obtained from the different fermentation phase of the high-salt liquid-state soy sauce fermentation,were added into the soybean sauce in order for comprehensive utilization soy sauce residues.In this study,there were three batches of soy sauce residues from five months,five and a half months,and six months,respectively.There were three batches of residues additive amount,the koji/residues additive ratio of 2:8,3:7,4:6 and 5:5,respectively.Moreover,the blank control group was the one without residue addition.The results showed a slightly lower content in total acid,total nitrogen,and reducing sugar as well as a lower value in pH,while no difference in moisture content was observed.As for organic acids,seven varieties were found in the pure soybean sauce while eight to nine varieties were observed in the residue-additive sauce.The tartaric acids and lactic acids were not detected in the former sauce.As for volatile flavor components,48 varieties were found in the pure soybean sauce while 60 to 67 varieties were found in the residue-additive sauce.Above all,residue-additive sauce presented no improvement in physicochemical properties but it had advantages on organic acid contents and volatile flavor components.It also showed that the fermentation period of 5 months and the koji/residues additive ratio of 8:2 were the best option.In addition,the production cost saved by about 20.6%The method used in this study was effective in waste residue recycle,with the value of the byproduct enhanced and the environment pollution caused by landfills avoided.Furthermore,the product obtained was of fine quality,healthy effect,and distinctive flavor because of its less salt addition and moderate residue addition.Simultaneously,the attractive colors and smells given by soy sauce residue fermentation would surely won overwhelming majority of customers.