Institute of Organic Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg, Germany.
Hamburg School of Food Science─Institute of Food Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany.
J Agric Food Chem. 2023 Feb 15;71(6):3093-3101. doi: 10.1021/acs.jafc.2c07498. Epub 2023 Jan 31.
Storage is a critical step in the post-harvest processing of hazelnuts, as it can lead to mold, rancidity, and off-flavor. However, there is a lack of analytical methods to detect improper or extended storage. To comprehensively investigate the effects of hazelnut storage, samples were stored under five different conditions for up to 18 months. Subsequently, the polar and nonpolar metabolome were analyzed by H NMR spectroscopy and chemometric approaches for classification as well as variable selection. Increases in hexanoic, octanoic, and nonanoic acid, all products of lipid oxidation and responsible for quality defects, were found across all conditions. Furthermore, the concentration of free long-chain fatty acids increased in samples stored at high temperatures. Harsh short-term storage resulted in an increase in fumaric and lactic acid, glucose, fructose, and choline and a decrease in acetic acid.
储存是榛子收获后处理的一个关键步骤，因为它可能导致霉菌、酸败和异味。然而，缺乏分析方法来检测不当或延长的储存。为了全面研究榛子储存的影响，将样品在五种不同条件下储存长达 18 个月。随后，通过 H NMR 光谱和化学计量方法对极性和非极性代谢组进行分析，以进行分类和变量选择。在所有条件下，均发现己酸、辛酸和壬酸增加，所有这些都是脂质氧化的产物，也是导致质量缺陷的原因。此外，在高温下储存的样品中，游离长链脂肪酸的浓度增加。苛刻的短期储存导致富马酸和乳酸、葡萄糖、果糖和胆碱增加，而乙酸减少。
