Study On Processing Technology And Storage Of Pepper And Salt Walnut Kernel

Walnut is one of the characteristic dried fruits in Xinjiang,which has very rich nutritional value.At present,there are still some problems in processing products of Xinjiang walnut kernel,such as single type of processing products and short storage time.This paper selects the formula,cooking process and packaging method of Xinjiang Yecheng 185 walnut to study the pepper and salt walnut kernel,and explores the influence of different processes on the quality of pepper and salt walnut kernel,so as to provide theoretical basis for production and processing.The main research contents are as follows:(1)Taking experiment material the effects of four spices(red pepper,hemp pepper,black pepper and white pepper)on the oil stability of walnut kernel and the optimum ratio of pepper and salt walnut kernel were analyzed by single factor test and saturated D-optimal design.The results showed that under the baking conditions at 140? during 40min,the comprehensive sensory scores of walnut kernel were ranked as hemp pepper>red pepper>white pepper>black pepper,the order of the peroxidation value of the four kinds of pepper and salt walnuts from small to large is:white pepper>black pepper>hemp pepper>red pepper.The addition ratio of flax pepper and white pepper was obtained by using peroxide value as index of saturated D-optimal design model,then combined with sensory score obtained the best spices for hemp pepper,salt and pepper walnuts hemp pepper.The result showed that salt and pepper walnut kernel flavor was best with lowest peroxide value when pepper addition was 0.575%,the salt addition is 0.77%and impregnated material liquid enrichment to original proportion was 1/4.(2)The baking process of salt and pepper walnuts was studied,and the peroxide value was used as the evaluation index,researched the influence of different levels of salt and pepper walnut meat quality,and peroxide value as the evaluation indexes,combining the response surface optimization method of salt and pepper walnut meat cooked process is optimized,finally get the baking process is:the best baking temperature 130?,bake time 40 min,the soaking time of 12 h.(3)The microwave process of salt and pepper walnuts was studied,and the peroxide value was used as the evaluation index,researched the influence of different levels of salt and pepper walnuts quality,again with peroxide value as the evaluation indexes,combining the response surface optimization method of salt and pepper walnut meat backed process is optimized,finally get the best technology for microwave:microwave power 50%,microwave time 6 min,soaking time 11 h.(4)Under the PET/Al/PE(vacuum)packaging,the predicted shelf life of the baking and cooking process is 748 d,with a relative error of 1.52%;the predicted shelf life of the microwave cooking process is 884 d,with a relative error of 4.24%.(5)The peroxidation values of pepper and salt walnut kernels was increased with the storage temperature in spite of different backing processes,the order of the peroxidation values of three temperatures was:5?<25?<45? when at 35 d,and the order of peroxidation values of different packaging under different processes was the same.While under the normal conditions,the order of the influence of different packaging on oil stability at 35 d was:PET/Al/PE(vacuum)>PET/PP/PE(vacuum)>PET/Al/PE(atmospheric pressure)>PET/PP/PE(atmospheric pressure).(6)In the processing process,the quality of roasted baked salt and pepper walnut kernels is better than microwave salt and pepper walnut kernels during the processing.In the processing process,the quality of roasted baked salt and pepper walnut kernels is better than microwave salt and pepper walnut kernels during the processing.The shelf life of the microwave process is higher than that of the baking process under the storage conditions of the same temperature and the same packaging method.