The Effect Of Irradiation Processing On Microbial Inactivition And Quality In Pickled Mustard

The irradiation sterilization plays an important role on mircorbial inavtivation and quality in Sichuan pickled. Otherwise sichuan pickled is a kind of popular traditional fermented vegetable products. In order to confirm the best suitable irradiation does. the microbia inactiviton of the pickled mustard were studied by different irradiation does of 60Co-gamma, meanwhile, the sensory evaluation were also studied to confirm the best suitable irradiation does, otherwise, the influence of the quality(includ the total acid. the nitrite. the flavor and the content of free amino acid) of the pickled mustard were studied between the 60Co-gamma irradiation and the thermal processing. these results were designed to provide a theoretical basis for using irradiation sterilization in the actual production of Sichuan pickles. The details were as follows:(1) Comfirming the best suitable irradiation does:in the condition of 4kGy,6kGy, 8kGy. 10kGy irradiation dose treatment of pickled mustard, the total number of colonies, lactic acid bacteria, mold and yeast countde down to below 1 log cfu/g. fecal coliform count were less than 3 MPN/g, it means that low doses of radiation can sterilize the vast majority of microbes in the samples; in the condition of 4kGy,6kGy,8kGy, 10kGy irradiation dose treatment of pickled mustard with the preserved performance, the results were as follows:in addition to the processing of the pickled mustard under the condition of 4kGy the samples appeared obviously phenomenon of bag inflation at 37℃. under other does of irradiation. the pickled mustard preserved at 37℃ had appeared no phenomenon of bag inflation. meanwhile. the pickled mustard under the condition of 4kGy preserved at normal tempreture had also appeared obviously phenomenon of bag inflation after six months, and under other dose of irradiation, the pickled mustard preserved at normal tempreature have appeared no phenomenon of bag inflation; in the condition of 4kGy,6kGy,8kGy, 10kGy irradiation dose treatment of pickled mustard with sensory evaluation, the results were as follows:there was little difference under 4kGy-6kGy irradiation dose of sensory quality of the samples, and under more than 8kGy irradiation does processing the samples affected the organization, as the irradiation does became higher, the pickled mustard tasted soft rotten, with poor chewiness, the higher irradiation does seriously affected the sensory quality.(2) Contrasting the quality of the pickled muasturd between the 60Co-gamma irradiation and the thermal processing:in the condition of 4kGy,6kGy,8kGy, 10kGy irradiation dose treatment of pickled mustard, the difference was no obvious of the 4kGy and other irradiation does were obviously different for the total acid, and there were obvious differences among all the irradiation does for the blank group of the nitrite; analysing the flavor of the pickled mustard in the condition of 4kGy,6kGy,8kGy, 10kGy irradiation dose, the results were as follows:under 4kGy-6kGy irradiation does, there were no obvious differences of total flavor with the samples which had not irradiated, meanwhile the allyl isothiocyanate became more than the samples which havd not irradiated under 6kGy～8kGy, isothiocyanate allyl influenced the flavor of salted vegetables as the characteristic flavor of salted vegetables, meanwhile the curcumene, zingiberene and the someride bisabolene. sesquiphellandrene of the zingiberene had became more than the samples which had not irradiated, pickled mustard had added the ginger as auxiliary materials to improve the flavor in the process of fermentation. Zingiberene as important in ginger ginger flavor substance had the effection of anti-cancer, anti-tumor, in the 4kGy-6kGy irradiation would’t destroy the main flavoring substances in pickled mustard, and was superior to the traditional heat sterilization method; analysing the content offree amino acid in pickled mustard in the condition of 4kGy, 6kGy,8kGy,10kGy irradiation dose, the results were as follows:under 4kGy-6kGy irradiation does, the content of free amino acid in pickled mustard had improved and under 8kGy-10kGy irradiation does the content of free amino acid in pickled mustard had reduced than the samples which had not irradiated, it meant that higher irradiation does was not good for the Sichuan pinkled and the suitable low irradiation does was better than the traditional heat treatment in the mircorbial inavtivation.