Peak Sweet Processing Adaptability And Shelf-life Prediction Of Chinese Chestnut

This research aimd to set up the processing suitability and make classification of 15 Chinese chestnut varieties in Yanshan area for peak sweet and extend the shelf-life of the suitable peak sweet chestnut varieties.The main results were as follows:1.Evaluation system of peak sweet processing in chestnut.The comprehensive value evaluation model was established: Y comprehensive value = 0.033 509 hardness +0.033 509 b value+0.185 173 moisture content +0.208 983 total sugar +0.108 499 browning degree +0.430 327 ediblerate as well as Chestnut raw material and peak sweet chestnut correlation model: Y=-1.109+0.015 good fruit rate-0.018 kernel hardness+0.008 starch were established.And both of the correlation coefficient of fitting test model were more than 0.96,which showed fitting degree was high and could be used for the evaluation of peak sweet processing suitability.2.According to the evaluation method established above,the quality indexes of 15 varieties of chestnut raw materials and products in Yan shan area had a variety of analysis.15 chestnut varieties could be divided into five classes,while the varieties of Yanguang,Yanlong,Yankui were determined very suitable,the varieties of Zipo,Yanping were more suitable,the varieties of Yankuan,Duanzhi,Zunyu,Da Banhong were suitable,the varieties of Yanxing,Yanzi,Zaosheng,Yanli,Yanqiu were basic suitable,but the varieties of Zaofeng was not suitable ultimately.3.Compared with the control samples without receiving any sterilization treatment,ultra-high pressure treatment(200,300,400,500 MPa)could dramatically reduce initial microbial count in peak sweet Chestnut,and inhibit the growth of dominant spoilage bacteria including total bacteria,yeast,mold and coliforms,which could be proved that 500 MPa was the best and the microbial count of produce was less than safety limit during 60 d.The peak sweet chestnut quality(sensory,soluble sugar,moisture content)evaluation under 300 MPa was the best.While,it was hard for consumers to accept the peak sweet chestnut that had bad status and appearance under 500 MPa.So,It was suggested that 300 MPa might be the best.4.The Gompertz model(R2>0.97)and the sensory quality evaluation results of peak sweet chestnut showed 300 MPa for 15 minutes was the best that could prolong the shelf-life to 38 d.And the results of verification test was 39 d,with 2.56% error,which meant the predicted value of the model was close to the actual value.5.300 MPa had a small effect on the cell morphology,flavor and core index(browning degree,hardness,moisture content,total soluble sugar)of peak sweet chestnut.So the conclusion of 3 and 4 were proved again.