Filtration is the most widespread stabilisation operation for extra virgin olive oil, preventing microbial and enzymatic changes. However, during the harvest, the workload of olive mills is at its peak. This results in two approaches to filtration: (i) delays it until after harvesting, increasing the risk of degraded oil quality, and (ii) filters it immediately, increasing the workload. The aim of our experiment is to assess the risk of delaying filtration and establish a safe delay time. Changes in the sensory profile and volatile compound contents were evaluated during 30 days in filtered and unfiltered samples. Significant differences were related to filtration: both turbidity grade and microbial contamination; no differences for the legal parameters were found. Two, contrasting, results were obtained with respect to oil quality: (i) the fusty defect, appearing in less than five days in unfiltered oils, leading to the downgrade of the oil’s commercial category, and (ii) filtration removing some lipoxygenase volatile compounds. Consequently, a fruity attribute was more pronounced in unfiltered samples until day five of storage; it seems that, from this point, the fusty defect masked a fruity attribute. Hence, filtering within a few days strongly reduced the risk of degraded oil quality compared to a delayed filtration.

中文翻译：

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过滤计划：新鲜生产的初榨橄榄油的质量变化。

过滤是最原始的特级初榨橄榄油的稳定化操作，可防止微生物和酶的变化。但是，在收获期间，橄榄磨的工作量已达到顶峰。这导致了两种过滤方法：（i）将其推迟到收割后，增加了油质下降的风险，（ii）立即对其进行了过滤，增加了工作量。我们实验的目的是评估延迟过滤的风险并建立安全的延迟时间。在30天内，对经过过滤和未经过滤的样品的感官特性和挥发性化合物含量进行了评估。显着差异与过滤有关：浊度等级和微生物污染；没有发现法律参数的差异。与此相反，在油质方面有两个结果：（i）过早的缺陷，在不到五天的时间内就出现在未过滤的机油中，导致该机油的商业级降级；（ii）过滤除去了一些脂氧合酶挥发性化合物。因此，直到储存的第五天，未过滤样品中的果味属性才更加明显。从这一点看来，过时的缺陷掩盖了果味的特性。因此，与延迟过滤相比，几天之内过滤可大大降低机油质量下降的风险。过分的缺陷掩盖了果味的特性。因此，与延迟过滤相比，几天之内过滤可大大降低机油质量下降的风险。过分的缺陷掩盖了果味的特性。因此，与延迟过滤相比，几天之内过滤可大大降低机油质量下降的风险。