Argyri Anthoula A, Panagou Efstathios Z, Nychas George-John E, Tassou Chrysoula C
Hellenic Agricultural Organization-DEMETER, Institute of Technology of Agricultural Products, Sof. Venizelou 1, Lycovrissi, 14123 Athens, Greece.
Department of Food Science and Human Nutrition, Laboratory of Microbiology and Biotechnology of Foods, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece.
Biomed Res Int. 2014;2014:515623. doi: 10.1155/2014/515623. Epub 2014 Aug 18.
Green fermented olives cv. Halkidiki were subjected to different treatments of high hydrostatic pressure (HHP) processing (400, 450, and 500 MPa for 15 or 30 min). Total viable counts, lactic acid bacteria and yeasts/moulds, and the physicochemical characteristics of the product (pH, colour, and firmness) were monitored right after the treatment and after 7 days of storage at 20(°)C to allow for recovery of injured cells. The treatments at 400 MPa for 15 and 30 min, 450 MPa for 15 and 30 min, and 500 MPa for 15 min were found insufficient as a recovery of the microbiota was observed. The treatment at 500 MPa for 30 min was effective in reducing the olive microbiota below the detection limit of the enumeration method after the treatment and after 1 week of storage and was chosen as being more appropriate for storing olives for an extended time period (5 months). After 5 months of storage at 20(°)C, no microbiota was detected in treated samples, while significant changes for both HHP treated and untreated olives were observed for colour parameters only (minor degradation). In conclusion, HHP treatment may introduce a reliable nonthermal pasteurization method to extend the microbiological shelf-life of fermented table olives.
绿橄榄品种哈尔基季基（Halkidiki）接受了不同的高静水压（HHP）处理（400、450和500兆帕，处理15或30分钟）。处理后以及在20℃储存7天以让受损细胞恢复后，监测了产品的总活菌数、乳酸菌和酵母菌/霉菌，以及产品的理化特性（pH值、颜色和硬度）。发现400兆帕处理15和30分钟、450兆帕处理15和30分钟以及500兆帕处理15分钟的处理方式效果不佳，因为观察到微生物群有恢复。500兆帕处理30分钟的处理方式在处理后以及储存1周后能有效将橄榄微生物群减少到计数方法的检测限以下，并被选为更适合长时间（5个月）储存橄榄的方法。在20℃储存5个月后，处理过的样品中未检测到微生物群，而仅在颜色参数方面观察到HHP处理和未处理橄榄都有显著变化（轻微降解）。总之，HHP处理可能引入一种可靠的非热巴氏杀菌方法来延长发酵食用橄榄的微生物货架期。
