【作者】 彭涛；

【导师】 邓洁红；

【作者基本信息】 湖南农业大学 ， 农产品加工及贮藏工程， 2012， 硕士

【摘要】 提供质量安全、营养卫生和美观新鲜的猪肉已成为消费者的要求,但猪肉保鲜时间短(冷鲜肉货架期6d),严重制约了肉品行业发展。为了解决这些问题,本文以新鲜猪里脊肉为研究对象,通过对比冷藏、微冻、冻藏三种不同保鲜技术,以贮藏过程中理化指标、感官评定综合指标以及微生物指标为猪肉的鲜度指标,探讨了微冻技术在猪肉保鲜中的适应性研究,以及探讨微冻保鲜技术在猪肉贮藏过程中的工艺优化和猪肉微冻保鲜复合包装技术应用研究,为猪肉保鲜提供理论与应用依据。本文主要结论如下：(1)冷藏技术在前期贮藏过程中猪肉品质较好,但保质期较短,不利于猪肉较长时间保鲜；冻藏条件下猪肉的保质期较长,但汁液流失率大,持水性差,组织结构损伤大,不利于猪肉的品质保藏；稳定微冻(-2℃)贮藏保质期明显高于冷藏技术,比冻藏技术短,但在汁液流失率和持水性以及组织结构上都要优于冻藏技术,能较好的保持猪肉的品质。综合猪肉的品质和货架期,表明微冻技术要优于冷藏与冻藏技术,是适合猪肉贮藏保鲜的技术。(2)在猪肉微冻保鲜技术的工艺优化研究中发现,-1℃贮藏条件的猪肉明显差于-2℃和-3℃；-2℃与-3℃之间的差异不大,从能耗角度来看,-2℃是贮藏猪肉最佳的温度。在-2℃贮藏温度下,猪肉国家二级鲜度至少可到达25d。.2±2℃贮藏条件猪肉汁液流失率明显大于-2℃和-2±1℃,但三者持水率差异不大；从理化指标和感官评价综合指标来看,-2±2℃贮藏条件明显差于-2℃和-2±1℃：-2℃和-2±1℃之间的差异不大,表明贮藏环境温度波动在1℃范围内对猪肉品质影响小。在-2±1℃贮藏环境下,猪肉国家二级鲜度约为25d。(3)经-25℃浸液降温方式的微动保鲜的猪肉明显优于-2℃风冷和--25℃风冷方式；猪肉经过-25℃浸液降温,再贮藏在-2℃温度下,猪肉国家二级鲜度至少可到达30d。另外,重量为100g肉样在-25℃浸液中降温到肉样中心温度-2℃所需的时间约为5min,-25℃风冷条件需要时间约为120min,-2℃风冷需要时间约为800min。(4)在稳定-2℃微冻贮藏环境中,复合保鲜包装技术要优于自然包装技术与真空包装技术,猪肉的国家一级鲜度至少有20d,猪肉的国家二级鲜度至少有30d。更多还原

【Abstract】 Provided quality safety, nutrition hygiene and beautiful&fresh pork has become the requirement of the consumers, However, Fresh-keeping storage time is short (shelf life of cold fresh meat is6days), which seriously restrict the development of meat industry. In order to solve this problem. The study treats the fresh meat as the research object, By comparing the different preservation technology of cold storage, partially frozen and frozen storage, To store process physical and chemical indexes, sensory comprehensive index and microbiology indicators for pork freshness index and discuss the partially frozen technology in the fresh pork adaptive research and a crisp fresh technology in pork in the process of storage technology optimization and fresh pork a crisp compound packing technology application research, to provide the theory and application of fresh pork basis.The main research results are as follows:(1) During store processing, The quality of Pork was better with the cold storage technology, but the shelf life was shorter, which was not good for a long time preservation; The quality guarantee period of the pork was long with Frozen hidden conditions, but sample in the Frozen with large liquid loss rate and poor water-holding capacity,and that its organizational structure were damaged large, this storage technology went against pork quality preservation. Stabilize a crisp (-2℃) storage samples of the liquid loss of less wastage rate and good water-holding capacity; Stable a crisp (-2℃) storage shelf life was significantly higher than the cold storage technology, than frozen hidden technology short, but in the water-holding capacity and liquid loss rate and organization structure than frozen hidden technique, the better to maintain the quality of the pork. The guarantee period of quality and comprehensive pork, show that partial freezing technology is superior to the cold storage and frozen hiding technology, and is suitable for pork fresh-keeping technology.(2) On study of pork a crisp fresh preserving technology.we can found that-1℃storage conditions of the pork in-2℃obvious difference and-3℃;-2℃and-3℃the difference between much from energy consumption perspective,-2℃is the best temperature storage pork. In-2℃storage temperature, the pork national secondary fresh degree can be reached at least25d.-2±2℃storage conditions pork liquid loss churn significantly greater than-2℃and-3℃, but the water rate difference three little; From the expiration period index and sensual evaluation comprehensive indicators,-2±2℃storage conditions obvious difference in-2and-2degree is-3℃;-2±2℃and the difference between the degree is-2±1℃is not big, show that storage environment temperature fluctuations in1℃scope of pork quality effect is small. In-2±1℃degree is storage environment, pork national level2fresh degree about25days.(3) According to the-25℃soaking liquid cooling way of keeping fresh of budge pork is obviously superior to-2℃air cooled and-25℃air cooling method; Pork with-25℃soaking liquid cooling, and storage in-2℃temperature, the pork national secondary fresh degree can be reached at least30d. In addition, weight of100g pork-25℃in soaking liquid cooling to the center of pork-2℃temperature the time required for about5min,-25℃air-cooled conditions need time was about120min,-2℃air-cooled need time was about800min.(4) Stable a crisp (-2℃) partial freezing storage environment, composite modified atmosphere packaging technology was superior to the natural packaging technology and vacuum packaging technology, pork freshness national level1at least20days, pork national level2fresh degree at least30days.更多还原