Study On Low-sugar Preserved Chestnut Processing Technology

Browing and short shelf life of low-sugar preserved chestnut affect its quality. In order to find some measures, some aspects were studied in this article: First, in order to optimize technologic parameter of low-sugar preserved chestnut, we discussed influence factors, such as thermal treating filling, cum boiling, vaccum preserving, baking and packaging, Ect; Second, the color change of the products in processing procedure was stuied.Third, adding moderate amount of starch enzyme to the chestnut preserved fruit, made parts of starch of chestnut changed into the sugar with the function of the starch enzyme, resolved the problems of the starch back to living and aging in the processing of chestnut. Finally, we systematically studied preservation stability of low-sugar preserved chestnut by Aw and wavelet irradiation. The results were as follows:1. Before the vaccumboiling produced, the thermal treatment not only effected on the color of the chestnut preserved and reduced to the activation of enzyme but also improved filter sugar rate. The best temperature and time were 100℃, 8min.2. Added 0.5% starch enzyme, liquation time was 105min, liquation temperature was 40℃, obvious action impact on the starch of chestnut.3. In the process of low-sugar preserved chestnut, the best color protecting liquid was 0.7%Nacl, 0.4% citric acid, 0.5%EDTA, 0.5%NaHSO₃.4. In order to increase satiation of low-sugar preserved chestnut and fill up sectional interspace, the best mixed filler were the combination of 5% glutin and 5% CMC.5.The factor such as vaccum degree, taking out vaccum time, charging time, dipping time exerted greatly influence on the vaccum preserved speed in the vaccum preserved process.vaccum degree: 0.086～0.090Mpa;taking out vaccum time: 30min; charging time: 60min; dipping time: 5h.6. The traditional boiling and baking produced significant effected on the color.The best conditions: boiling temperature and time were 25℃, 5h; Baking temperature and time were 80℃,2h.7. Aw had significant effected on the microbial stability in low-sugar preserved chestnut. The microbe in products with Aw 0.80 around reproduced quickly during preservation at room temperature, which would affect the quality of products, while molds and yeast in products with Aw<0.65 remained dormant during preservation. The water-affinity substances can reduce Aw.The best combination water-affinity substances: sodium lactic acid 0.3%, citric 0.3%, propylene glycol 0.6%.8. As a new type energy sources and technology, wavelet was better than normal ways in sterilizing.The time of Sterilization in wavelet more than 20s was effective controling growth of microbes.