The Development Of The Conditioning Steak And The Establishment Of Shelf-life Prediction Model

Conditioning beef products,a class of nutritional, delicious, convenient, fast, low-fat meat products get into good graces by more and more new consumers.With the substantial growth of production and consumption, Conditioning beef products will gradually become the main trend of meat consumption in china. However, for its starting late,conditioning products in our country lags behind developed countries in processing. And the conditioning steak has not been sterilized, at the same time, fluctuation of temperature at storage, transport, sales process seriously shorten its shelf life. These problems limit the development of steak industry. In view of the above problems, the Eye Round provided by Kang Mei farm was used to determine the optimal formula of conditioning steak by adding potassium lactate instead of salt, combined with single factor experiment and response surface optimization. And eating quality, nutritional quality and texture characteristics of different degree of doneness conditioning steak was studied. At last, the shelf life of the conditioning steak was studied. On the base of it, the remaining shelf life prediction modeling was established by a simulating fluctuation of temperature at storage, transport, sales process.The above study was intended to provide a theoretical basis and practical guidance for the production process, transport and sales of our conditioning steak.The main research achievements were as follows:1.Study on the slice thickness of conditioning steak. Results showed that, with the increase of the slice thickness, tenderness, texture characteristics fel, chewiness increased at first and then decreased. So 10 mm was the best slice thickness.2.Optimization of basic formula of conditioning steak.The optimized dosage was Sodium replacement ratio 22%, Tenderizer 0.7%,Soy protein isolate 1.0%, Amylum 3.0%.3.Study on the conditioning steak quality of different degrees of doneness. As the degrees of doneness increased, tenderness significantly decreased, L*, a*, b* values showed a reduced trend, cooking loss significantly increased. The hardness, springiness, cohesiveness, chewiness and resilience increased, water content decreased, the content of fat, protein and ash content were increased. Comprehensive evaluation of conditioning steak quality of different degrees of doneness based on principal component analysis. The resurts showed that comprehensive evaluation of Wel-done conditioning steak was the highest, Medium Well was higher, and the Rare was the lowest. Therefore, it was suggested that the conditioning steak should cooked to Well Done.4.The Shelf-life model of the conditioning steak at a constant temperature was established by the method of Regression-Analysis. The Shelf-life model at a constant temperature was Lnφ=8.372(1000/T)-26.813 by measuring the total bacterial accounts. And shelf life of the conditioning steaks was 402 days when stored at-18℃. The model at a constant temperature was Lnφ=7.828(1000/T)-24.768 by measuring the total bacterial accounts. And shelf life of the conditioning steaks was 369 days when stored at-18℃.5.The remaining Shelf-life prediction model was established by a simulating fluctuation of temperature at storage, transportation and sales process. The remaining Shelf-life prediction model at a fluctuat temperature was ΦSL=exp{8.372(1000/Tm)-26.501+ln[ln(Nf/N0)]} × {1- ∑tn/exp[8.372(1000/Tn)-26.501+ln(ln(Nf/N0))]} by measuring the total bacterial accounts. The remaining Shelf-life prediction model at a fluctuat temperature was ΦSL=exp{7.828(1000/Tm)-24.768+ln[ln(Nf/N0)]} × {1- ∑ tn/exp[7.828(1000/Tn)-24.768+ln(ln(Nf/N0))]} by measuring the total volatile basic nitrogen. Experimental results were in good agreement with the theoretical.