Study On Processing Technology,Quality And Flavor Of Mussel Sauce

As an important economic shellfish,Mussels not only have high yields and rich nutrition,but also taste good.In China,the processing of Mussels is still rough presently,so the degree of processing and utilization of Mussels needs to be improved.Fermented aquatic food has a long history,especially fish sauce,shrimp sauce and other products play an important role in the condiment industry because of their unique flavor.By inoculating Aspergillus oryzae to the Mussels,this paper studied the effects of different fermentation conditions on the quality of Mussels sauce and analyzed the changes of physical and chemical properties as well as the flavor of Mussels sauce in the fermentation process.Meanwhile,the process of Mussels seasoning is optimized.in order to broaden the scope of Mussels processing and application and improve the flavor quality of fermented aquatic condiments.The main conclusions are as follows:Firstly,the effects of different fermentation conditions on the quality of Mussels sauce were studied.Aspergillus oryzae was selected as the strain starter,and soybean and rice were mixed to make seed koji.The effects of koji material to shellfish meat ratio,salt content,fermentation temperature and fermentation time on the quality of Mussels sauce were studied with sensory evaluation and amino acid nitrogen(ANN)as evaluation indexes.The results showed that under the preparation process of 1:1 starter to shellfish meat ratio,14% salt content and 40 ℃ thermal insulation fermentation for 24 days,the amino acid nitrogen content of Mussels sauce was the highest to 0.65 g / 100 g,and the sensory score was the best.The whole product was yellowish brown,shiny,delicious,mellow and moderately viscous.Therefore,it was determined as the final fermentation process condition.Secondly,the changes of physical and chemical properties of Mussels sauce during fermentation were studied.The change of amino acid nitrogen content(ANN)in the fermentation process was measured by acidimeter method.The results showed that the value increased rapidly at first and then slowly,reaching the highest value of 0.65 g/100 g on the 24 th day.The total acid was determined by PH meter potentiometric titration.It was found that the total acid showed an upward trend and increased rapidly in the early stage of fermentation.It began to increase slowly on the 6th day and finally reached 1.47 g/100 g.The content of reducing sugar was determined by titration.It was found that its content also increased first and then decreased.The a* value,b* value and L* value of Mussels sauce were measured by color difference meter.Except that for a slight decrease in L* value in the later stage,they all showed an increasing trend with the progress of fermentation.The content of biogenic amine was determined by HPLC.The results showed that the content of biogenic amine increased with the increase of fermentation time,but it still met the safety standard.Thirdly,the changes of flavor substances in Mussels sauce during fermentation were analyzed.Based on the quantitative analysis of free amino acids by HPLC,the results showed that the content of total free amino acids increased continuously,and finally reached 32.38g/100 g.In addition,the content of Umami amino acids aspartic acid and glutamate was the highest,which contributed the most to the overall taste of Mussels sauce.The volatile flavor substances in the fermentation process were analyzed by headspace solid phase microextraction gas chromatography-mass spectrometry(HS-SPME-GC-MS),and the key odor active substances were determined by calculating the relative odor activity value(ROAV).The results showed there were 59 kinds of phenolic compounds,including 6 acids,5 ketones,2 phenols,9alcohols,20 aldehydes,1 sulfur compound,7 heterocyclic compounds and 9 esters.A total of19 key volatile aroma compounds were screened by the calculation of ROAV.The results showed that with the progress of fermentation,the fishy smell of the Mussels sauce gradually weakened,and the good smells such as meat flavor,flower and fruit flavor and vegetable flavor gradually enriched and enhanced.Finally,the flavoring technology of Mussels seasoning was optimized and its antioxidant activity was also determined.Taking the sensory evaluation as the evaluation index,the proportion of Mussels sauce,the amount of seasoning oil and concentrated Mussels cooking liquid as well as the fried Mussels meat were optimized by single factor and Response surface test,respectively.The results showed that the best seasoning technology of Mussels sauce was50.9% seasoning sauce,9.4% concentrated Mussels cooking liquid,5.9% seasoning oil and 5%fried meat.In addition,Mussels sauce had certain hydroxyl radical scavenging and total antioxidant capacity,which is positively correlated with the mass concentration of the sample.