Background The aroma chemistry and the contribution of the aroma compounds to the anti-oxidative properties of roasted yam have yet to be characterized. The growing popularity of roasted yam in regions where they are being consumed calls for a concerted effort to elucidate their aroma chemistry as well as their anti-oxidative properties. Results The aroma compounds in roasted white yam (Dioscorea rotundata) were isolated and identified using static headspace-gas chromatography-mass spectrometry (SH-GC-MS) and gas chromatography-olfactometry (GC-O). In addition, the anti-oxidative activities of the most abundant volatile heterocyclic compounds (2 pyrroles, 4 furans and 3 pyrazines) were evaluated on their inhibitory effect towards the oxidation of hexanal for a period of 30 days. Twenty-nine aroma-active compounds with a flavour dilution (FD) factor range of 2-256 and an array of odour notes were obtained. Among them, the highest odour activities (FD ≥ 128) factors were determined for 2-acetyl furan and 2-acetylpyrrole. Other compounds with significant FD factors ≥ 32 were; 2-methylpyrazine, ethyl furfural, and 5-hydroxy methyl furfural. Conclusion Results of the anti-oxidative activity showed that the pyrroles exhibited the greatest antioxidant activity among all the tested heterocyclic compounds. This was followed by the furans and the pyrazines which had the least antioxidant activity.

中文翻译：

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香气化合物对烤白山药 (Dioscorea rotundata) 抗氧化特性的贡献。

背景芳香化学和芳香化合物对烤山药的抗氧化特性的贡献还有待表征。烤山药在消费地区越来越受欢迎，需要共同努力来阐明它们的香气化学以及它们的抗氧化特性。结果采用静态顶空-气相色谱-质谱(SH-GC-MS)和气相色谱-嗅觉(GC-O)对烤白薯(Dioscorea rotundata)中的香气成分进行分离鉴定。此外，对含量最多的挥发性杂环化合物（2 吡咯、4 呋喃和 3 吡嗪）的抗氧化活性进行了为期 30 天的对己醛氧化的抑制作用的评估。获得了 29 种香气活性化合物，其风味稀释 (FD) 因子范围为 2-256，并具有一系列气味。其中，2-乙酰呋喃和2-乙酰吡咯的气味活性（FD≥128）因子最高。其他具有显着 FD 因子 ≥ 32 的化合物是；2-甲基吡嗪、乙基糠醛和5-羟甲基糠醛。结论 抗氧化活性结果表明，吡咯在所有被测杂环化合物中表现出最大的抗氧化活性。其次是抗氧化活性最低的呋喃和吡嗪。2-甲基吡嗪、乙基糠醛和5-羟甲基糠醛。结论 抗氧化活性结果表明，吡咯在所有被测杂环化合物中表现出最大的抗氧化活性。其次是抗氧化活性最低的呋喃和吡嗪。2-甲基吡嗪、乙基糠醛和5-羟甲基糠醛。结论 抗氧化活性结果表明，吡咯在所有被测杂环化合物中表现出最大的抗氧化活性。其次是抗氧化活性最低的呋喃和吡嗪。