| "Qingliu Beancurd strick" is protected by geographical indications of Qingliu,Fujian province.Moreover,it was produced by a unique and tranditional processing technology,and attracted deeply lots of customers.In order to enrich the kinds of products and develop a series of Qingliu Beancurd strick,we analysed Qingliu Beancurd strick nutrients,determined the flavoring technique of ready-to-eat Beancurd strick by tests of single factor and Orthogonal experiments,optimized hurdle factor during sterilized process by experiments of center combination and bulit a dynamic model of sterilization.We also couducted hazard analysis to products by Weibull Mode,and set up the equation to predict their shelf life.In addition,we applied the theory of HACCP into the production of ready-to-eat Beancurd strick,with the reference to IS022000 standard.The results were as follows:(1)In the process of Ready-to-use Beancurd strick seasoning,the key factors are salt,sugar,and pepper.The best formula is:the Chinese prickly ash 0.8%,star anise 0.2%,hemp pepper 0.5%,salt 0.2%,sugar 1%,5’-ribonucleotide 0.5%,capsicum 5%.The product at this point has good taste and special flavor of Beancurd strick.(2)The way of seasoning research results indicate that the optimum process is:the ratio of condiment and water is 1:3.5,and soaked for 35 min at 5 ℃.The products by using the process have good chewness and color.Moreover,they are neither too hard,nor too soft.The process reduce nutrients to a minimum.(3)Through the Design-Expert 8.0 software,we analysed the results by using center combination and Orthogonal experiment,and the result is that regression model equation of sterilization process is Y = 7.23 + 0.30 A+ 0.40B + 1.68C + 0.45 D-0.93 CD-0.22 A2-0.43 B2-2.33 C2-0.17D2,and the correlation coefficient R2 equal to 0.9540.(4)The best combination by optimized under the sterilization conditions is:the temperature of secondary sterilization is 93 ℃,the sterilization time is 42 min,the content of citric acid is 1.0%,the sorbic acid potassium is 0.04%,and the sodium acetate content is 0.04%.(5)we studied the quality changing rules of ready-to-eat Beancurd strick during the storage,which indicated that the physical and chemical indicators was stable,the content of moisture remained at 38%to 43%,and temperature had more influences on total plate count,in particularly,the reslut of E.coli tests was negative.Hardness had a trend of slow growth along the increasing of storage time.The chewness was within the range from 0.5 to 1.5N,and browning reaction also appeared.The sensory quality was the key factors affecting the shelf life of samples.(6)We got the regression equation of the shelf life by using accelerated shelf lifetest,which was .We also couducted hazard analysis to products by Weibull Mode and predicted the shelf life of the samples under different storage temperature.The results were the shelf life is 196 days,75 days,11 days and 5 days at 25℃,30℃,35℃ and 40℃ separately.Weibull shelf life equation was logt = 0.1237logH + 2.0455(7)We confirmed the key control points by applied the theory of HACCP into the production of ready-to-eat Beancurd strick.The key control points were the acceptance of raw materials,seasoning at low temperature,vacuum packing and secondary sterilization.In addition,we take the preventive measures for every key control point to ensure quality and safety of products. |
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