LFMFP, Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Member of Food2Know, Coupure Links 653, B-9000 Ghent, Belgium.
LFMFP, Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Faculty of Bioscience Engineering, Ghent University, Member of Food2Know, Coupure Links 653, B-9000 Ghent, Belgium.
Int J Food Microbiol. 2014 May 16;178:120-9. doi: 10.1016/j.ijfoodmicro.2014.03.012. Epub 2014 Mar 18.
Sweet bell peppers are a significant constituent of retail, chilled-stored and packaged food products like fresh salads, marinades and ready-to-eat (RTE) meals. Previously, through general screening of the Belgian market and by means of source tracking analysis in a plant manufacturing minimally processed, vegetable salads the susceptibility of fresh-cut sweet bell peppers to lactic acid bacterium (LAB) contamination was substantiated. The determination of the metabolic profiles of Leuconostoc gelidum subsp. gasicomitatum and Lactococcus piscium, two major psychrotrophic, spoilage-related LAB species, on sweet bell pepper (SBP) simulation medium under different packaging conditions - 1.) vacuum: 100% N2, 2.) air: 21% O2, 79% N2, 3.) MAP1: 30% CO2, 70% N2 and 4.) MAP2: 50% O2, 50% CO2 - facilitated a better understanding of the spoilage potential of these microbes as well as the presumptive contribution of O2 in the spectrum of produced volatile organic compounds (VOCs) associated with poor organoleptic properties of food products. Generally, none of the applied gas compositions inhibited the growth of the 4 L. gelidum subsp. gasicomitatum isolates, however the presence of O2 resulted in buttery off-odors by inducing primarily the accumulation of diacetyl and pungent "vinegar" smell due to acetic acid. The 3 tested isolates of L. piscium varied greatly among their growth dynamics and inhibition at MAP2. They exhibited either weak spoilage profile or very offensive metabolism confirming significant intraspecies diversity.
甜椒是零售、冷藏和包装食品的重要组成部分，如新鲜沙拉、腌料和即食 (RTE) 餐。此前，通过对比利时市场的全面筛选，并通过对工厂生产的最低限度加工的蔬菜沙拉中的源追踪分析，证实了新鲜切割甜椒易受乳酸菌 (LAB) 污染。在不同包装条件下——1. 真空：100% N2；2. 空气：21% O2，79% N2；3. MAP1：30% CO2，70% N2；4. MAP2：50% O2，50% CO2——确定了嗜冷、与变质相关的两种主要 LAB 物种——嗜冷明串珠菌亚种和气生肠球菌在甜椒 (SBP) 模拟培养基上的代谢谱，这有助于更好地了解这些微生物的变质潜力，以及 O2 在与食品感官特性不佳相关的挥发性有机化合物 (VOC) 产生谱中的假定作用。一般来说，没有一种应用气体成分抑制了 4 株嗜冷明串珠菌亚种气生肠球菌分离株的生长，然而，O2 的存在通过主要诱导二乙酰和刺鼻的“醋”气味的积累导致了黄油异味，因为 O2 存在导致了二乙酰和刺鼻的“醋”气味的积累。测试的 3 株嗜冷明串珠菌亚种气生肠球菌分离株在 MAP2 中的生长动态和抑制作用差异很大。它们表现出较弱的变质特征或非常令人讨厌的代谢，证实了显著的种内多样性。
