Díaz Pedro, Nieto Gema, Garrido María Dolores, Bañón Sancho
Department of Food Technology, Nutrition and Hygiene, Veterinary Faculty, University of Murcia, Espinardo, Murcia 30071, Spain.
Meat Sci. 2008 Oct;80(2):287-92. doi: 10.1016/j.meatsci.2007.12.002. Epub 2007 Dec 8.
The aim was to study spoilage during the refrigerated storage of cooked pork loin processed by the sous vide method. Samples were packaged under vacuum into polyamide-polypropylene pouches, cooked at an oven temperature/time of 70°C/12h, chilled at 3°C and stored at 2°C for 0, 5 or 10 weeks. Microbial (psychrotrophs, lactic acid bacteria, Enterobacteriaceae, moulds and yeasts), physical-chemical (pH, water activity, TBARS, acidity, L(∗)a(∗)b(∗) colour, texture profile analysis and shear force) and sensory (appearance, odour, flavour, texture and acceptance) parameters were determined. The results showed that sensory spoilage preceded microbiological spoilage of sous vide pork loin. Counts bellow 1logcfu/g of psychrotrophs, anaerobic psychrotrophs, Enterobacteriaceae and lactic acid bacteria were detected in any control week, while moderate counts (2-3logcfu/g) of moulds and yeasts were found. Minor changes in water activity, lipid oxidation, CIELab colour, hardness, cohesiveness or gumminess were associated with spoilage of pork loin, only decreases of lactic acid, springiness and shear force were observed. The pork loin was unacceptable after 10 weeks. This loss of acceptance was mainly due to the deterioration of meaty flavour and odour, although the loss of appearance, juiciness and firmness also contributed. Moderate warmed-over and rancidity were detected. The sensory analysis was the most effective method for determining the shelf life of the sous vide pork-based dishes.
目的是研究真空低温烹饪法加工的熟猪里脊肉在冷藏储存期间的变质情况。将样品真空包装到聚酰胺 - 聚丙烯袋中，在70°C/12小时的烤箱温度/时间下烹饪，在3°C下冷却并在2°C下储存0、5或10周。测定微生物（嗜冷菌、乳酸菌、肠杆菌科、霉菌和酵母菌）、物理化学（pH值、水分活度、硫代巴比妥酸反应物、酸度、L(∗)a(∗)b(∗)颜色、质地剖面分析和剪切力）和感官（外观、气味、风味、质地和可接受性）参数。结果表明，真空低温烹饪猪里脊肉的感官变质先于微生物变质。在任何对照周中，嗜冷菌、厌氧嗜冷菌、肠杆菌科和乳酸菌的计数均低于1logcfu/g，而霉菌和酵母菌的计数为中等水平（2 - 3logcfu/g）。水分活度、脂质氧化、CIELab颜色、硬度、内聚性或胶黏性的微小变化与猪里脊肉的变质有关，仅观察到乳酸、弹性和剪切力的下降。10周后猪里脊肉不可接受。这种可接受性的丧失主要是由于肉味和气味的恶化，尽管外观、多汁性和紧实度的丧失也有影响。检测到中度的加热过度和酸败。感官分析是确定真空低温烹饪猪肉菜肴货架期的最有效方法。
