Processing Of Spicy Chili Chicken Grain By Microwave And Its Fresh Keeping By Modified Atmosphere Packaging

With the change of diet habits,Chinese-prepared food is gradually becoming a mainstream in modern fast-paced life.Compared to traditional baked drying process,microwave heating has more merits and popularization values,such as fast heating speed,controllability and energy efficiency.With its good appearance and taste,the microwaved spicy chili chicken(MSCC)which is new,convenient,timesaving and save,was developed on a lab scale.As for quality control of MSCC,a standard process and a seasoning quantification were used to provide support for development of Chinese-prepared food and industrialization of MSCC.The quality of Chinese-prepared food during storage has increasingly aroused widespread concern.There is a wide use of modified atmosphere packaging(MAP)in packaging of fresh fish,meat,fruits and vegetables but very seldom in Chinese-prepared food.To investigate the effect of different MAP conditions on the quality of MSCC during cold storage and to prolong the shelf-life of MSCC,the microbial indexes,fat oxidation,protein oxidation and volatile flavor compounds of MSCC were measured.(1)The three factors and three levels of response surface experiment were designed on the basis of single factor experiment.To determine the best condition,sensory test evaluated by fuzzy mathematics was also carried out.And the optimal conditions were as follows:the chili powder 4.81 g,the starch sauce 17.25 g,heating time 8.31 min.Under such process condition,the sensory score of MSCC was 4.297.Moisture content,cooking loss and color of MSCC were measured.The results showed that moisture content decreased and the cooking loss increased as microwave heating time increased.And the addition of starch helped to reduce the water loss during heating.With microwave heating time prolonged and more chili pepper added,we saw a declined L*value and a elevated a*value.(2)In this experiment,the sensory evaluation,basic composition,color,fat oxidation and volatile flavor compounds of MSCC and stir-fried spicy chili chicken(SSCC)were compared.The score of MSCC and SSCC were 78%and 82.25%,respectively.The results indicated that the color and taste of MSCC were slightly worse,and the flavor was better.The POV values of MSCC and SSCC were 0.1812 meq/kg(sample)and 0.2548 meq/kg(sample),respectively.The TBA values of MSCC and SSCC were 0.5687 mg MDA/kg and 0.8248 mg MDA/kg,respectively.There were 32 and 23 volatile compounds detected from MSCC and SSCC,respectively.MSCC has lower fat content,lower fat oxidation,and more volatiles.(3)MSCC was packaged with different gas compositions:A:100%N2,B:10%O2+90%N2,C:20%O2+80%N2,D:20%02+40%N2+40%C02,E:20%O2+80%CO2,and was tested for quality changes after 30 days’ storage.The microbial community diversity of MSCC was also analyzed.The results showed that POV,TBA values and total microbial counts and hexanal content increased,free thiols and unsaturated alcohols dropped continually during storage.High O2 levels aggravated fat oxidation,protein oxidation and the growth of microorganism while anaerobic conditions extended shelf life of MSCC.Carbon dioxide could inhibit the growth of microorganisms,reduce species diversity,and curb fat oxidation.(4)MSCC was packaged with different gas compositions:A:100%N2,B:10%O2+90%N2,C:20%O2+80%N2,D:20%02+40%N2+40%CO2,E:20%O2+80%CO2,and was tested for quality changes after 180 days’ frozen storage.The results showed that POV values increased,while the increasing trend slowed down gradually after 120 days.TBA values increased slowly after 90 days.The oxygen boosted fat oxidation while carbon dioxide inhibited fat oxidation.But Carbon dioxide had little effect on the quality changes of MSCC under frozen conditions.Content of volatile compounds decreased significantly under frozen conditions,unsaturated alcohols,esters and ketones dropped while nonanal increased during frozen storage.Frozen storage conditions resulted in a more pronounced inhibition of fat oxidation and the growth of microorganisms than cold storage conditions.Frozen MSCC retained a high quality after 180 days.