Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, Faculty of Agriculture, Aristotle University of Thessaloniki, GR 54124 Thessaloniki, Greece.
Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, Faculty of Agriculture, Aristotle University of Thessaloniki, GR 54124 Thessaloniki, Greece.
Int J Food Microbiol. 2015 Sep 2;208:122-30. doi: 10.1016/j.ijfoodmicro.2015.06.001. Epub 2015 Jun 6.
The effect of an autochthonous starter culture developed by oleuropeinolytic strains belonging to the Lactobacillus plantarum group on the physicochemical and microbiological characteristics and the biophenol content of table olives fermented under reduced salt conditions was studied. Black (cv. Kalamata) and green (cv. Chalkidikis) olives were fermented in two different kinds of brine (Brine A containing 2.3% NaCl, 32.3mM Ca-acetate and 33.9mM Ca-lactate and Brine B containing 4% NaCl, pH5.0 in both brines). The sensory attributes of olives fermented by oleuropeinolytic starter culture assessed by a trained panel did not differ significantly compared with industrial processing. It is possible to carry out significant changes in table olive processing applying a completely microbiological procedure using oleuropeinolytic strains of the L. plantarum group as both the debittering and the fermentation agent in order to achieve improved sensorial and nutritional characteristics of the final product. Table olives processed by the suggested methodology may constitute a good source of biophenols in the diet, especially hydroxytyrosol and tyrosol. The inactivation potential of Escherichia coli O157 EDL-932 and Listeria monocytogenes Scott A in olives fermented by oleuropeinolytic starter culture was evaluated. The population of each pathogen in olive homogenates of both cultivars is inactivated by more than 6logCFU/ml in less than 24h. When whole fermented olives were submerged in peptone/saline (containing 6.7logCFU/ml of the relevant bacterial pathogen) for 30min followed by rinsing in distilled water, the population of viable foodborne pathogens dropped more than 4 logs in olive pulp. During subsequent storage at 22 or 4°C the population of L. monocytogenes Scott A was further eliminated under the detection limit in both olive cultivars whereas the population of E. coli O157 EDL-932 could be detected in olives stored in peptone/saline at 22°C for 7days. The inhibitory effect of olives fermented by oleuropeinolytic starter culture in reduced salt brines on pathogens is due to the antimicrobial activity of the phenolic compounds and the antagonistic action of the associated microflora.
研究了属于植物乳杆菌组的橄榄苦苷裂解菌株开发的本土起始培养物对低盐条件下发酵的餐桌橄榄的理化和微生物特性以及生物酚含量的影响。用两种不同的盐水（盐水 A 含有 2.3%NaCl、32.3mM 醋酸钙和 33.9mM 乳酸钙，盐水 B 含有 4%NaCl，两种盐水中的 pH 值均为 5.0）发酵黑（cv. Kalamata）和绿（cv. Chalkidikis）橄榄。经过训练的小组评估，用橄榄苦苷裂解起始培养物发酵的橄榄的感官属性与工业加工没有显著差异。通过使用橄榄苦苷裂解的植物乳杆菌组菌株作为脱苦剂和发酵剂，在餐桌橄榄加工中进行重大改变是有可能的，以便获得最终产品的感官和营养特性的改善。用建议的方法加工的餐桌橄榄可能成为饮食中生物酚的良好来源，特别是羟基酪醇和酪醇。评估了橄榄苦苷裂解起始培养物发酵的橄榄中大肠杆菌 O157 EDL-932 和单核细胞增生李斯特菌 Scott A 的失活动力。在两种品种的橄榄匀浆中，每种病原体的种群在不到 24 小时内就被灭活超过 6logCFU/ml。当整个发酵橄榄浸泡在含有 6.7logCFU/ml 相关食源性病原体的蛋白胨/盐水（peptone/saline）中 30 分钟，然后用蒸馏水冲洗时，橄榄果肉中的活菌数下降超过 4 个对数。在随后在 22 或 4°C 下储存时，在两种橄榄品种中，李斯特菌 Scott A 的种群进一步减少到检测限以下，而在 22°C 下储存在蛋白胨/盐水中的橄榄中可以检测到大肠杆菌 O157 EDL-932 7 天。低盐盐水发酵的橄榄对病原体的抑制作用是由于酚类化合物的抗菌活性和相关微生物区系的拮抗作用。
