Abstract The quality of olive oil depends, among other factors, on the quality of the olives used. Ergosterol is proposed as a marker for olives degraded by yeast or mold, since yeast as well as mold produce ergosterol, whereas olives do not. Ergosterol was determined in olive oil by on-line HPLC-GC-MS, using the high efficiency of HPLC to separate ergosterol from the sterols that are present at far higher concentrations. The detection limit was around 0.1 mg kg−1 oil. Among 50 extra virgin olive oils, 5 contained less than 0.1 mg kg−1 ergosterol, 18 were in the range 0.1–2 mg kg−1 and the highest concentration was 39 mg kg−1. Oil extracted from degraded olives contained ergosterol in a range of 21–289 mg kg−1, with higher values in the samples with a high number of yeast and mold cells. Being a marker for degraded olives, the ergosterol concentration should be related to fatty acid ethyl esters, formed by ethanol from fermentation by yeast, but the ergosterol concentration is considered more pertinent, since the ethyl esters only detect activity of yeast and their concentration depends on the conversion of the ethanol to fatty acid ethyl esters by transesterification in the olives.

中文翻译：

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麦角甾醇作为在橄榄油生产中使用降解橄榄的标志物

摘要 橄榄油的质量取决于所用橄榄的质量等因素。麦角甾醇被提议作为被酵母或霉菌降解的橄榄的标记物，因为酵母和霉菌会产生麦角甾醇，而橄榄则不会。通过在线 HPLC-GC-MS 测定橄榄油中的麦角甾醇，利用高效的 HPLC 将麦角甾醇与浓度高得多的甾醇分离。检测限约为 0.1 mg kg-1 油。在 50 种特级初榨橄榄油中，5 种含有少于 0.1 mg kg-1 的麦角甾醇，18 种在 0.1-2 mg kg-1 范围内，最高浓度为 39 mg kg-1。从降解橄榄中提取的油含有 21–289 mg kg-1 范围内的麦角甾醇，在具有大量酵母和霉菌细胞的样品中具有更高的值。作为退化橄榄的标记，