Natrella Giuseppe, Difonzo Graziana, Calasso Maria, Costantino Giuseppe, Caponio Francesco, Faccia Michele
Department of Soil, Plant and Food Sciences, University of Bari, Via Amendola 165/A, 70126 Bari, Italy.
Foods. 2020 Oct 12;9(10):1446. doi: 10.3390/foods9101446.
Undesired volatile organic compounds (VOCs) can negatively affect the flavor of fresh food products; especially those characterized by a mild and delicate aroma. Finding connections between chemical and sensory analyses is a useful way to better understand the arising of off-flavors. A study was conducted on stracciatella; a traditional Italian cream cheese that is emerging on international markets. Samples were prepared by adding two different preservatives (alone or combined): sorbic acid and an olive leaf extract. Their influence on flavor preservation during refrigerated storage was investigated by chemical, microbiological and sensory analyses. A strong change of the VOC profile was ascertained after 8 days in the control cheese and in the sample added with leaf extract alone. The samples containing sorbic acid, alone or in combination with leaf extract, gave the best chemical and sensory results, demonstrating a significant shelf-life extension. In particular, these samples had lower concentrations of undesired metabolites, such as organic acids and volatiles responsible for off-flavor, and received better scores for odor and taste. Ex and Ex-So samples had significantly higher antioxidant activity than Ctr and So throughout the entire storage period, and the color parameter shows no differences among samples taken on the same day. The use of the olive leaf extract, at the concentration tested, seemed to be interesting only in the presence of sorbic acid due to possible synergic effect that mainly acted against Enterobacteriaceae.
不需要的挥发性有机化合物（VOCs）会对新鲜食品的风味产生负面影响；尤其是那些具有温和细腻香气的食品。找出化学分析和感官分析之间的联系是更好地理解异味产生的一种有用方法。对斯特拉奇亚泰拉奶酪进行了一项研究，这是一种在国际市场上崭露头角的传统意大利奶油奶酪。通过添加两种不同的防腐剂（单独或混合使用）来制备样品：山梨酸和橄榄叶提取物。通过化学、微生物和感官分析研究了它们在冷藏储存期间对风味保存的影响。在对照奶酪和仅添加叶提取物的样品中，8天后确定挥发性有机化合物（VOC）谱有强烈变化。含有山梨酸的样品，单独或与叶提取物混合使用，在化学和感官方面都给出了最佳结果，表明保质期有显著延长。特别是，这些样品中不需要的代谢物浓度较低，如导致异味的有机酸和挥发性物质，并且在气味和味道方面得分更高。在整个储存期间，Ex和Ex-So样品的抗氧化活性明显高于Ctr和So，并且同一天采集的样品的颜色参数没有差异。在所测试的浓度下，由于可能主要对肠杆菌科起作用的协同效应，橄榄叶提取物似乎仅在有山梨酸存在时才有趣。
