The Influence Of Irradiation On The Quality Of Pickled Cabbage During Storage

The pickled cabbage is fermented with fresh vegetables and then processed by dipping productsit,it is very delicious and rich in nutrition. The pickled cabbage is a common dish on the table. At present, the domestic mainly uses the heat sterilization to the pickled vegetable processing product to carry on the sterilization preservation. This method will not only undermine the nutrition of kimchi, but also have a certain impact on its taste. Radiation sterilization is a non thermal sterilization technology, it not only has a good effect of sterilization, but also better to maintain the quality of food. In this experiment, we studied the effect of 60Co-gamma ray on the sterilization effect of Sichuan bulb and the quality of the preserved period.In this experiment, we use pickled cowpea as materials, study the 60Co-ray on Sichuan pickled cowpea effect and quality of cowpea in the storage period. The results are as follows:(1) A total of 60 volatile flavor compounds were detected in Sichuan pickled cowpea, including 44 kinds of hydrocarbons,7 kinds of lipids,3 kinds of alcohols,3 kinds of aromatic compounds,3 kinds of aldehydes and ketones. The content of the hydrocarbon in the non sterilized bubble was 17.46%, after irradiation, the alkane flavor compounds decreased. The 3 kGy treatment group was 12.75% ,4kGy treatment group was 10.89%,5 kGy treatment group was 13.99% ,6 kGy was 15.31%,7 kGy treatment group was 15.17%. But after heat sterilization treatment, the changes of alkanes are larger up to 46.69%; After sterilization, the changes of aromatic compounds were different, the content of aromatic compounds in the thermal sterilization group was significantly decreased, aromatic compounds were not detected in 4 kGy and 5 kGy treatment groups in irradiation sterilization group.the contents of other treatment groups were significantly increased; After sterilization treatment, the content of lipid was significantly decreased, and the 6 kGy,7 kGy treatment group did not detect lipid substances; The initial content of alcohol flavor substances was 4.19%, after heat sterilization treatment, the content decreased, but little change, for 4.05%; After irradiation sterilization treatment, the content of alcohol in the bubble was increased, and the dose of irradiation treatment was different; The content of aldehydes and ketones pickled cowpea is not high, only 0.77%, heat sterilization group is not detected flavor compounds of aldehydes and ketones, while the content of irradiation treatment group decreased, but the radiation dose was different.(2) The effect of irradiation on the sterilization of Sichuan pickled cowpea was significant. Irradiated samples of pickled cowpea, in addition to 3 kGy, the total number of colonies was 3 visible colonies,4-7 kGy irradiation dose treatment of kimchi by the initial bacteria 4.1 (LG (cfu/g)), down to 2 (LG (cfu/g)) the following. The initial bacterial content of lactic acid bacteria was 3.7 (LG (cfu/g)), and the initial bacterial biomass was 4.1 (LG (cfu/g)). After 3-7 kGy irradiation were reduced to 2 (LG (cfu/g)) following. The colibacillosischanges is reduced from 360mpn/g to less than 3mpn/g. In storage test at 37?,3 kGy pickles samples in the preservation of the 14 d when a slight bulging bag,4 kGy pickles samples in the preservation of the 15 d when a slight bulging bag, it was found that the main cause of the inflation bag was Candida albicans,and the total number of 3 kGy was 3.6 (LG (CFU/g)?he total number of 4 kGy was 3.67 (LG (CFU/g)). Above 5 kGy irradiation group were not pickled cowpea bulging bag happened in 15 d. After the end of the collection, the total number of colonies was determined. Total bacterial count was 3.3 (CFU/g) in 5 kGy irradiation doses. The total number of colonies in 6kGy and 7 kGy treatment group was less than 2 (LG (CFU/g)), This result is consistent with the heat treatment effect.(3) The effect of irradiation on the sensory quality of Sichuan pickled cowpea was different because of the different irradiation doses, the scores of sensory quality of irradiated groups showed a decreasing trend during normal storage; The scent of 3 kGy and 4 kGy treated groups gradually decreased with time, and occur slight bulging bag on the 60 d, when the first 90 d, produce slight smell of corruption, resulting in decreased sensory quality. The sensory quality of the 5-7 kGy treatment group has been in an acceptable range.(4) The effect of irradiation on the physical and chemical properties (titratable acid?pH?nitrite?colour?crispness) of Sichuan pickled cowpea was different with the prolonging of irradiation dose and preservation time.Irradiation and heat treatment had no significant effect on the titratable?pH. During the normal temperature preservation, the content of the acid and the pH value of the irradiation treatment group were not significantly changed by 5 kGy or more. Irradiation treatment and heat treatment had a great influence on the nitrite of the bulb, and showed different growth and decline in the late preservation, but always less than the national pickled standard and Sichuan pickles local regulations; With L*, a*, b* and c* values to reflect the color of pickles. The effect of heat treatment and irradiation treatment on the color is different. The heat treatment of pickled cowpea L* value, a* value, b* value and C* value decreased, irradiation treatment had little effect on b* and c*, but the a* value and L* value are affected, where the a* value decreases, the L* value increases. The values of L*, a*, b* and C* of each treatment group were decreased gradually during normal storage. However, there was no significant change in the treatment group of 5 kGy or above. The effect of irradiation treatment on the fracturability of pickled cowpea was smaller than that of heat treatment, and 5-7 kGy treatment group was more able to maintain the fracturability value of the pickled cowpea in the preservation period.