Study On Presevation Of The Pucheng Chuantoumo

Pucheng Chuantoumo is a traditional food of Shaanxi province,it is attracting more and more people because of its unique shafe,sweet and delicious characteristics.However,it is easy to get rotten during the storage.Thus,exploring the suitable method and prolonging the shelf-life is the key to realizing the development of its industrialization.The effect of hot sterile packaging,sterile packaging at room temperature and food additives on quality of products were studied in this paper.The main results are showed as follows:(1)The effect of three kinds of methods on microbial quantity during the storage of products ware studied.In terms of the total plate count,the change pace of hot sterile packaging at room temperature was faster than that of hot sterile packaging.Sterile packaging Pucheng Chuantoumo at room temperature got bad in the sixth day,its shelf-life was five days.Mould was not detected in the hot sterile packaging Pucheng Chuantoumo within 15 days;The effect of natamycin on microbial quantity was the best among four kinds of food additives,the best concentration was 0.3 g/kg,the shelf-life of Pucheng Chuantoumo would be extended to seven days.(2)Under 25 ? storage conditions,the changes of physicochemical indexs of hot sterile packaging and sterile packaging at room temperature were measured.The results showed,the water content and whiteness of the hot sterile packaging increased firstly and reduced at last,the sterile packaging at room temperature reduced constantly.The water content and whiteness of the hot sterile packaging was higher than the sterile packaging at room temperature within sixth days;pH reduced firstly and increased at last;The phenomenon of staling becomed more and more obvious during the storage,water holding capacity reduced,?H and the ratio of peak heights increased,amylopectin recrystallization took place,the binding force between starch and protein becamed weakly,the pace of staling of Pucheng Chuantoumo packaged at room temperature was faster than that of the hot sterile packaging.The content of acid compounds was the highest in all compounds,during the storage,the content of esters,alcohols and acids decreased,the content of aldehydes,ketones and hydrocarbons increased,three new hydrocarbons and three new ketones appeared.(3)The hardness,adhesiveness and chewiness of Pucheng Chuantoumo increased significantly,resilence and cohesiveness reduced,the texture parameters rangeability of the hot sterile packaging was lower than the sterile packaging at room temperature;The sterile packaging Pucheng Chuantoumo at room temperature got bad in the sixth day,they were not edible,however,the sensory quality of the hot sterile packaging was good within 15 days.(4)With the correlation and factor analysis of the changes in quality parameters,the microbial indicators(the total plate count and the number of mould)and texture parameters were selected as the main indicators to evaluate the deterioration of Pucheng Chuantoumo.(5)The shelf-life of the sterile packaging Pucheng Chuantoumo at room temperature was five days,the shelf-life of Pucheng Chuantoumo would be extended to seven days if natamycin(0.3 g/kg)was used,mould was not decected in the hot sterile packaging within 15 days,in addition,the sensory quality of the hot sterile thermal packaging was good within 15 days,it was edible,Thus,the shelf-life of Pucheng Chuantoumo would be extended to 15 days by using the hot sterile packaging technology.