【作者】 徐宁；

【导师】 肖红梅；

【作者基本信息】 南京农业大学 ， 食品工程， 2012， 硕士

【摘要】 泡椒凤爪作为传统禽类酱卤肉制品的主要品种之一,具有高蛋白、低脂肪、低热量、口感细腻、酸辣开胃等特色,深受广大消费者的喜爱。目前,我国关于泡椒凤爪的研究较少,泡椒凤爪市场发展也比较缓慢,关键影响因素是泡椒凤爪在加工、贮藏、运输和销售等一系列过程中,由于冷链系统不完善,极易遭受微生物的污染,导致产品质量不稳定,货架期短,不利于产品工业化发展。本研究以真空包装泡椒凤爪为试材,研究不同贮藏温度对泡椒凤爪贮藏期间产品品质变化的影响；分析贮藏过程中感官品质、微生物指标及理化指标之间的相关性；结合回归方程对泡椒凤爪不同贮藏温度下的货架期进行预测,为企业产品开发、工艺改进等提供理论依据。具体研究内容及结果如下：1.泡椒凤爪贮藏过程中的品质变化以南京某公司真空包装泡椒凤爪为实验材料,定期检测其在10℃、25℃、30℃和37℃下条件下,感官品质、pH值、挥发性盐基氮(total volatile basic nitrogen, TVB-N)、硫代巴比妥酸反应物(thiobarbituric acid reactive substance, TBARS)、菌落总数、大肠菌群等指标,并进行相关性分析。结果表明：在不同的贮藏温度、时间下,各项指标变化差异显著(p<0.05)。产品感官品质随着贮藏温度的升高、贮藏时间的延长表现为组织变软发黏,色泽变暗无光泽,伴有大量汁液流出并出现不良的气味；pH值呈先下降后上升的趋势,且贮藏温度越高变化越显著；TVB-N和菌落总数呈持续上升的趋势；TBARS值在贮藏前期呈上升趋势,在贮藏后期呈下降的趋势。其中贮藏温度与各指标(pH值、TVB-N、TBARS值、菌落总数和感官指标)均呈极显著相关(p<0.01)；菌落总数与感官品质、pH值、TVB-N和TBARS值也均呈极显著相关(p<0.01),说明菌落总数与产品各贮藏品质指标的变化具有显著相关性。贮藏温度和微生物是导致本产品劣变的主要因素。2.泡椒凤爪在不同贮藏温度下的货架期预测在研究不同贮藏温度(10℃、25℃、30℃和37℃)下真空包装泡椒凤爪贮藏特性变化的基础上,对实验数据进行多元逐步回归分析,建立不同温度下产品货架期的预测方程,经过残差分析、修正和验证后,各温度下货架期预测方程分别为：Y10℃=5.570×TVB-N+234.434×TBARS+6.194×菌落总数-52.737(R2=0.951)；Y25℃=3.337×TVB-N+106.333×TBARS+9.146×菌落总数-23.511(R2=0.988):Y30℃= 0.823+0.662×TVB.N+4.225×菌落总数(R2=0.955):Y37℃=9.238+0.143×TVB -N+ 14.193×TBARS+1.1530×菌落总数-2.432×感官评分(R2=0.985)。通过对回归方程的方差分析结果表明,回归模型均有很大的F值和极小的P值(p<0.001),回归方程的决定系数R2均大于0.95,表明回归模型能很好的预测产品的货架期。将各指标的限值带入回归方程,预测得出真空包装泡椒凤爪10℃、25℃、30℃和37℃贮藏条件下的货架期分别为206 d、141 d、35 d和18 d,实验预测结果与实际贮藏寿命接近,说明该模型可作为工厂实际生产中的理论参考依据。更多还原

【Abstract】 Pickle Chicken feet is one of the main varieties of the traditional poultry product which has a vast number of consumers because of its high protein, low fat, low calorie, delicate taste, sour and hot appetizer features. But the market of chicken feet product develops slowly. The key factor which restrict the market development is the microbial contamination, which leads to the instability of product quality, short shelf life, and unsafely for product industrialization development. The microbial contamination mostly happens in the processing, storage, transportation and sales, because the cold chain system is not perfect. This study used vacuum-packed pickle chicken feet as test materials. Sensory quality, pH, TVB-N, TBARS and total bacterial count of chicken feet stored at different storage temperature were detectived. We analyzed the correlation of sensory quality, microbial indictors and physicochemical index. Combining with the regression equation to predict the shelf life of vacuum-packed chicken feet with pickled peppers at different storage temperatures was researched, which will help the product market development of the company. The contents and results are shown as follows:1. Study on quality characteristics of vacuum-packed pickle chicken feet during different temperatures storage.Sensory evaluation, pH, TVB-N, TBARS and total number of bacterial colony count with the storage time were evaluated and undertook correlation analysis. The results revealed that the storage temperature and time had a significant effect (p<0.05) on the quality and shelf life of vacuum-packed pickle chicken feet. With the storage temperature and storage time extension, the product sense appeared as soft tissue of sticky, darken in color dull, with a large amount of sap and undesirable odor; the trend of pH values was decreased with storage time rising, then increased. The higher storage temperature, the more significant changes of pH values; TVB-N and the total number of colonies had continued to rise trend; TBARS value rose in early period of storage, and showed a downward trend at the late period of storage. In addition, storage temperature had an obvious correlation with quality property indexes (p<0.01); the total number of bacterial colony also had an obvious correlation with sensory quality, pH, TVB-N and TBARS (p<0.01). This showed that storage temperature and microorganism were the main factors leading the deterioration of vacuum-packed chicken feet with pickled peppers.2. Research on prediction shelf-life of vacuum-packed chicken feet with pickled peppers at different temperatures.On the basis of storage properties data of chicken feet with pickled peppers at 10℃、 25 ℃、30℃、37℃, using multiple regression equation, we established the products shelf life prediction equation under different temperature. After the residual analysis, modification and verification, prediction equations of the shelf life under different temperature were respectively that Y10℃= 5.570 x TVB-N+234.434 × TBARS+6.194 x TBC-52.737 (R2=0.951); Y25℃= 3.337 × TVB-N+106.333 × TBARS+9.146 x TBC-23.511 (R2 =0.988); Y30℃= 0.823+0.662 x TVB-N+4.225 x TBC (R2=0.955); Y37℃= 9.238+ 0.143 × TVB-N+14.193 × TBARS+1.153 × TBC-2.432 × Sensory evaluation (R2 =0.985). Based on the results of variance analysis to regression equation showed that regression equations have high F value and minimum value (P<0.001), the regression equation of the coefficient of determination R2 were greater than 0.95, which showed that the regression model can well predict the shelf life of the product. Each index limit value into the regression equation, when stored at 10℃, the shelf life was 206d; when stored at 25 ℃, the shelf life was 141d; when stored at 30℃, the shelf life was 35d; when stored at 37 ℃, the shelf life 18d. The experimental results showed the prediction shelf life is similar as practical life. The equation could be used as the actual production theoretical basis.更多还原