| Sweet corn,due to the strong seasonality,short storage period,difficult to preserve and other problems,most of the fresh sweet corn is processed into quick-frozen sweet corn to achieve year-round supply.Although the output of sweet corn is large in our country,the research on the processing of sweet corn is relatively late,and the variety of deeply processed sweet corn products is not rich enough,which greatly restricts its development.So,the nutritional composition of local sweet corn was determined and analyzed in the process of processing into quick-frozen form and under different treatment methods,and its applicability as soft packaging sweet corn kernels was judged.According to the nutritional characteristics of sweet corn,combined with the characteristics of flexible packaging food,such as long shelf life,easy to carry,easy to transport and so on,the technology and parameters were obtained through experiments,and the soft packaging sweet corn kernels were processed in order to develop more sweet corn products,increase its economic value,and provide strong technical support for sweet corn processing industry.The main results are as follows:(1)The nutritional components of sweet corn with different treatments were determined and analyzed.the results showed that compared with ordinary corn,this variety of sweet corn had higher water content,higher crude protein content,higher fat content and lower starch content.sweet corn will lose water and soluble sugar through treatment;because the content of glutamic acid is the highest in the content of amino acid,it has fresh taste.Comprehensive analysis of this variety of sweet corn is a suitable raw material for making sweet corn kernels in ready-to-eat soft packaging and candied sweet corn with low sugar.(2)Using quick-frozen sweet corn kernels as raw materials,through a series of analysis such as single factor test and response surface optimization test,the best technology and parameters of sweet corn kernels in ready-to-eat soft packaging were determined as follows: pre-cooking time was 6 minutes;when color protection,the addition amount of citric acid was 0.24%,vitamin C addition was 0.17%;when hardening soaking,the time was 43 minutes,the concentration of calcium chloride was 0.1%;when cooking,the time was 3 minutes,and the addition amount of salt was 3%;by sterilization,the temperature was 100℃ and the time was 10 min.Under this process and parameters,due to color protection,hardening and the addition of salt,the sour,astringent and salty taste of the electronic tongue increased;the product conformed to the commercial aseptic test;the shelf life at room temperature is 180 days.(3)Using quick-frozen sweet corn kernels as raw materials,through a series of analysis such as single factor test,response surface optimization test and so on,the best technology for making candied sweet corn with low sugar was determined as follows: color protection,blanching,boiling,dipping,drying,roasting,returning to soft "vacuum packaging" sterilization.The best parameters are blanching temperature 100℃,blanching time 2min,0.2% citric acid for color protection,0.3% xanthan gum+0.3% CMC for filling,cooking time 14 min,impregnation time 5h,baking temperature 65℃,baking time 5h,microwave sterilization irradiation 20 s.Under this process and parameters,the sour,sweet and astringent taste of electronic tongue increased due to color protection,sugar infiltration and filling process,its sensory,physicochemical and microbiological indexes all met the product quality standard;the shelf life at room temperature is 270 days. |
