Study On Formula And Processing Technology Of Specially Umami Concentrated Chicken Soup

As one of the five basic flavors,umami can make the overall taste of food more harmonious.In recent years,research on processing technologies to improve food umami is very limited,so it is necessary to explore new and efficient umami improvement technologies to meet the urgency of the food industry.This subject mainly focused on five aspects:ultrasonic combined with sodium bicarbonate（Na HCO₃）to assist chicken soup to increase umami,radio frequency pretreatment to assist chicken enzymatic hydrolyzate to increase umami,special umami concentrated chicken soup recipe,flavor enhancement process and dilution ratio optimization.The main research conclusions are as follows:First,the basic technical parameters for umami chicken soup were determined and the effects of 0.1%（w/w）Na HCO₃ combined with different powers（0 W,120 W,180 W,240 W,300 W）of ultrasonic treatment on the taste and flavor of chicken soup were studied.The results showed that the basic process of boiling chicken soup with 0.1%（w/w）Na HCO₃ solution for 15 minutes at 45k Hz for 90 minutes can better extract the umami substances in chicken.As the ultrasound power increased,the color of the chicken broth gradually became darker.The chicken soup treated with120 W ultrasound power combined with 0.1%（w/w）Na HCO₃ had the highest inosinic acid（IMP）content and was the most umami.Chicken soup under 180 W ultrasound contained the most abundant volatile flavor components.Chicken soup under 240 W sonication had the highest concentration of umami amino acids.Chicken broth under 120 W sonication also had the maximum equivalent umami concentration（EUC）value.The results of the electronic tongue and sensory evaluation both showed that the chicken soup treated with 120 W ultrasound combined with 0.1%（w/w）Na HCO₃ had better flavor and sensory characteristics,that is,the saltness and umami taste was significantly improved,and the unpleasant tastes such as sourness,bitterness,and astringency were suppressed.The flavor is stronger than that of traditionally boiled chicken soup.Secondly,the chicken was pretreated by ultrasound（600 W,30 min）,infrared radiation（90°C,30 min）,and radio frequency（120 mm,30 min）,respectively.Then,complex proteolytic enzymes were used for hydrolysis,and the differences in taste and flavor of chicken enzymatic hydrolyzate treated with different physical fields were discussed.The results showed that the chicken enzymatic hydrolysate after RF pretreatment with 120 mm plate spacing had the best overall taste,which could suppress the unpleasant taste of the enzymatic hydrolysate,and had a relatively strong umami expression and maximum EUC value.The chicken enzymolysate treated with infrared radiation at90°C had a stronger flavor and had the largest proportion of umami amino acids.However,the overall taste of the chicken enzymatic hydrolyzate treated with 600 W ultrasound wave was not significantly different from that of the control group,but the flavor was significantly improved.The changes of chicken protein secondary structure indicated that infrared and radio frequency treatment can greatly transform chicken protein spatial structure,and physical field treatment can convert moreα-helix,β-turn and random coil structure intoβ-sheet.Therefore,120 mm plate spacing RF pretreatment for 30 min is more suitable for industry to product low cost and high umami chicken enzymatic hydrolyzate.Finally,the optimal special umami concentrated chicken soup recipe and flavor enhancement process were determined by response surface methodology and orthogonal optimization method.According to the stability coefficient,the optimum addition amount of chicken oil was explored.Moreover,a fuzzy mathematical model was established to determine the optimal dilution ratio.The optimal special umami concentrated chicken soup formula was 7%enzymatic hydrolyzed powder,0.45%dried scallops,0.27%xylose,and 0.4%salt.Based on the orthogonal optimization method,the optimal flavor enhancement process was obtained as follows:the concentration of thiamine is0.5%,the concentration of cysteine is 0.5%,the heating time is 75 min,and the heating temperature is 80℃.The stability of the system was the best when the amount of chicken fat was 15%.According to the sensory evaluation results of fuzzy mathematics evaluation,it is concluded that 30times of dilution was the optimal dilution ratio of the special umami concentrated chicken soup product.