【作者】 孟鸿菊；

【导师】 杨坚； 徐毅；

【作者基本信息】 西南大学 ， 农产品加工及贮藏工程， 2008， 硕士

【摘要】 近几年来,随着人们消费观念的转变,我国肉类消费发生了明显的结构性变化,呈现从冷冻肉-热鲜肉-冷却肉的发展过程。冷却肉的生产已经呈现出强劲的发展势头,但冷却肉的货架期一直是限制其发展的关键因素,如何延长冷却肉的保鲜期成了冷却肉加工业亟待解决的问题,采用合理有效的保鲜技术是保证高品质冷却肉不可缺少的重要环节。本论文以冷却牛肉为原材料,研究了包装材料对冷却牛肉保鲜效果的影响;贮藏温度对冷却牛肉保鲜效果的影响;联合保鲜技术对冷却牛肉保鲜效果的影响。开发利用栅栏技术,对冷却牛肉真空热缩包装保鲜技术进行了初步研究。为冷却牛肉真空热缩包装保鲜技术的推广提供理论依据和技术指导。本试验通过对贮藏期间冷却牛肉感官综合评定、理化指标(pH值、TVB-N、球蛋白沉淀、汁液流失率)、微生物指标(菌落总数)的测定来探讨真空热缩包装技术对冷却牛肉保鲜效果的影响。实验结果如下:第一部分:包装材料对冷却牛肉保鲜效果的研究选取(PE、PVC、Ny6、POF、Cryovac(r)BDF-2001)5种不同阻隔性的热缩材料,采用热水收缩和热风收缩两种不同的热缩方式处理冷却牛肉,对冷却牛肉在低温贮藏过程中的细菌总数、TVB-N、汁液流失率、pH值、球蛋白沉淀、感官综合评定进行了分析,结果表明:1.在不同的包装材料中,具多层共挤复合聚烯烃的高阻隔Cryovac(r)BDF-2001热缩袋包装冷却牛肉取得了最好的保鲜效果,在初始菌落总数相同的条件下,冷藏过程中各项指标均好于其它组,延长了冷却牛肉的保质期。2.在不同的真空热缩包装方式用于冷却肉的保鲜中,通过对冷却牛肉贮藏期间各项指标的测定分析可看出,真空热水收缩包装方式效果明显好于真空热风收缩方式,热水收缩处理方式使冷却牛肉的保鲜期达到15天以上。第二部分:贮藏温度对冷却牛肉保鲜效果的研究选取试验一Cryovac(r)BDF-2001热缩袋作为包装材料,采用真空热水收缩包装和0℃、4℃、6℃三个温度作为冷却牛肉的贮藏温度,通过试验测得的各项指标进行比较分析,发现0℃下冷却牛肉取得了较好的保鲜效果,在此温度下,在整个贮藏期间冷却牛肉的汁液流失率较其它组低,感官综合评定分值最高,TVB-N值和菌落总数值也最低,有效地延长了冷却牛肉的保鲜期。第三部分:联合保鲜技术对冷却牛肉保鲜效果的研究结合试验一、二部分的研究结果,选取Cryovac(r)BDF-2001热缩袋作为包装材料,0℃作为贮藏温度,进一步研究天然保鲜剂和真空包装方式、天然保鲜剂和真空热水收缩方式相结合处理冷却牛肉,对不同处理组的保鲜效果进行综合比较分析,结果表明:1.从对照组(无菌蒸馏水结合真空包装、无菌蒸馏水结合真空热水收缩包装)处理组中处理冷却肉,单独比较分析这两组对照组,从试验所得的各项指标比较分析,结果表明,无菌蒸馏水结合真空热水收缩包装处理组用于冷却牛肉的保鲜取得了较好的保鲜效果。2.比较分析对照组和经保鲜液浸渍的处理组,从试验测得的各项指标分析比较,发现经保鲜液处理的冷却牛肉,无论是结合真空包装还是真空热缩包装方式,在相同条件下抑菌效果明显好于对照组,在初始菌数相同的条件下,处理组的菌落总数在整个贮藏过程中呈现先下降后上升的趋势,而对照组的菌落总数值一直处于上升趋势,这说明经保鲜液处理的冷却牛肉有效发挥了抑菌作用,抑制了微生物的生长繁殖,减缓了冷却牛肉的腐败变质,有效的提高了冷却牛肉的品质。3.在四种保鲜液(保鲜液1:0.2%茶多酚+1.0%壳聚糖+1.0%乙酸;保鲜液2:0.2%茶多酚+0.05%Nisin;保鲜液3:1.0%壳聚糖+1.0%乙酸+0.05%Nisin;保鲜液4:0.2%茶多酚+1.0%壳聚糖+1.0%乙酸+0.05%Nisin)中,保鲜液4处理组抑菌效果最好,从试验测得的各项指标表明茶多酚、壳聚糖、Nisin按一定的比例复配,能充分发挥各自的抑菌作用,起到优势互补,协同增效的作用,取得了最好的保鲜效果,延长了冷却牛肉的保鲜期。4.相同保鲜液处理冷却牛肉中,联合保鲜包装技术(保鲜液结合真空热水收缩包装、保鲜液结合真空包装)处理冷却牛肉,保鲜液结合真空热水收缩包装取得了较好的保鲜效果。使冷却牛肉的保鲜期延长到25天以上。更多还原

【Abstract】 In the last few years, with the transformation of people’s expense idea, meats expense in our country has had the obvious constitutive change, from the cold frozen meat - hot fresh meat -chilled meat. The cooling meat’s production has had the strong development momentum, but the cooling meat’s shelf life has been the key aspect of limiting its development, how to lengthen the freshness days of chilled meat has becomed the urgent question to be solved in the chilled meat processing industry, Taking the reasonable effective technology of maintaining freshness is essential important link. the high quality cooling meat The paper take chilled beef as a raw material, studied the influence of the packing material to chilled beef ; the influence of the storage temperature to chilled beef; the influence of the union maintaining freshness technology to chilled beef . The developing and using the stockade technology in chilled beef , researched preliminarly on vacuum contraction packing about maintaining freshness in order to provide the theory basis and the technical guidance for VHCP of chilled beef .This experiment test sense organ synthesis evaluation, the physics and chemistry target (the pH value, TVB-N, Globulin precipitate, Weight loss)、the microorganism target (Bacterias total) during storage days the determination to discuss the effects on VHCP technique to chilled meat for keep freshness. The experimental result is as follows:Part 1: The research on packing material to chilled beef freshnessChoose (PE, PVC, Ny6, POF, Cryovac(r) BDF-2001) 5 kinds of different impediment pyrocondensation materials, uses two kind of different pyrocondensation way (the hot water contraction and the hot blast contracts) to deal with chilled beef, Analysising bacterium total, TVB-N, the juice rate of personnel loss, pH the value, the globulin to precipitate, the sense organ synthesis evaluation, the results follows:1. During the different packing material, Cryovac(r) BDF-2001 pyrocondensation bag with the multi-layer altogether to push the compound polyolefine is the best, and obtaines the best freshness effect, the each target studied is better than other group and lengthen the freshness dates of chilled beef.2. Among the different VHCP ways used in chilled beef, We can get the point from the each target studied during the storge days that the VHWCP is better than the VHBCP in maintaining freshness, and lengthen the freshness days to above 15 days.Part 2 : The storage temperature on freshness of chilled beefChoosing the packing material of Cryovac(r) the BDF-2001 pyrocondensation bag and taking VHWCP and 0℃, 4℃, 6℃three temperatures as the storage temperature .Analysis and find that 0℃had the better fressness effect , under this temperature , the weight loss is less than the other goups , and the total sensoy evalucation is highest. the TVB-N value and the total is lowest .It can lengthen the freshness dates of chilled beef.Part 3 : The union maintaining freshness technology on chilled beefChoosing the packing material of Cryovac(r) the BDF-2001 pyrocondensation bag and taking VHWCP and 0℃as the storage temperature , further studing the natural antistaling agent and the vacuum packing way, the natural antistaling agent and the VHWCP dealing with chilled beef Carrying on the synthesis comparative analysis and indicated finally:1. From CK (CK+VP, CK+VHWP) dealed with chilled beef, Comparatively analysising on these two groups, from the experimental obtained each target comparative analysis, indicating finally, the distilled water union VHWCP treatment group used in chilled beef on maintain freshness get better freshness effect.2. the comparative analysis CK and the treatment group , found that the chilled beef dealed with the freshness fluid which together with VP or VHWC ways can control the bacteria well by the research target , underthe same bacteria total , The initial bacteria total of the treatment group changed from low to high during the total storge days .but the CK group is high from beginning to the end , It can get the point that the treatment group with fressness liquid have worked on controlling growth of micbacteria and keep the freshness of the chilled beef , enhancing the quality of chilled beef.3. Among the 4 kind of freshness liquid (1: 0.2%Tp+ 1.0% Ch+ 1.0% Ac ; 2 : 0.2%Tp + 0.05%Nisin; 3: 1.0% Ch+ 1.0% Ac + 1.0% Ch+ 1.0% Ac; 4 : 0.2%Tp +1.0% Ch+ 1.0% Ac +0.05%Nisin), the treatment group with freshness liquid 4 can control the growth of bacteria well, We can take the conclution from the target studied that Tp.Ch.together Nisin can make use of the controlness bacteria , and the effect will work on, It can lengthen the freshness days effectively.4. During the same fresh liquedmaintains on chilled beef , the union freshness packing technique (fresh liquid and VHWCP ; fresh liquid and VP), fresh liquid and VHWCP ways can get Better freshness effect.It can increase the freshness days to above 25 days.更多还原