了解实验室诱导和常规干燥的坚果中的麦卡达米亚核中的棕色中心形成的化学途径
Marcela Martinez1, Helen M Wallace1, Chris Searle2
1Centre for Planetary Health and Food Security, School of Environment and Science, Griffith University, Nathan, QLD, 4111, Australia.
Heliyon
|February 15, 2024
概括
马卡达米亚坚果在高温和湿度下存储不当会导致棕色中心,这是一个主要的缺陷. 适当的干燥和储存实践对于防止树木坚果生产中的这些损失至关重要.
科学领域:
- 农业科学 农业科学
- 食品科学 食品科学 食品科学
- 收获后技术 收获后技术
背景情况:
- 马卡达米亚坚果的生产在全球范围内激增,但像棕色中心这样的内部缺陷导致了重大的经济损失.
- 马卡达米亚核中的棕色中心是一种变色缺陷,与不适当的储存条件,特别是高温和湿度有关.
- 棕色中心形成背后的特定化学变化在很大程度上仍未被描述.
研究的目的:
- 为了研究麦卡达米亚坚果中棕色中心核和白色核之间的化学差异.
- 确定与棕色中心形成相关的关键化学化合物和反应.
- 在受控实验室条件下比较棕色中心开发与行业最佳实践.
主要方法:
- 麦卡达米亚坚果样品经过受控的高湿度和温度条件 ("诱导") 或使用澳大利亚麦卡达米亚协会 (AMS) 推的方法在收获后立即干燥.
- 分析包括测量水分,糖,脂肪酸度,过氧化物值,营养含量和挥发性化合物.
- 气色谱-质谱法 (GC-MS) 用于识别挥发性化合物.
主要成果:
- 与AMS干燥样本 (1.44%) 相比,诱导棕色中心的发生率明显高 (10.33%).
- 诱导的棕色中心比诱导的白色核具有更高的水分含量.
- 识别了诸如nonanoic acid,octanoic acid和2,3-butanediol等挥发性化合物,这些化合物与棕色中心形成和脂质氧化有关.
结论:
- 在高温和湿度下进行不适当的干燥和储存是马卡达米亚坚果中棕色中心形成的主要驱动因素.
- 糖水解和梅拉德反应与棕色中心的发展有关.
- 建议实施适当的干燥和储存实践,以减轻棕色中心缺陷造成的损失.
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