Department of Food and Nutrition, University of Helsinki, Post Office Box 66, Agnes Sjöbergin katu 2, FI-00014 Helsinki, Finland.
Department of Food and Nutrition, University of Helsinki, Post Office Box 66, Agnes Sjöbergin katu 2, FI-00014 Helsinki, Finland.
Food Chem. 2021 Jan 1;334:127577. doi: 10.1016/j.foodchem.2020.127577. Epub 2020 Jul 18.
A precise quantification of insect chitin is needed in order to avoid overestimation of crude protein due to chitin-bound nitrogen. An UPLC/FLR method was optimized and validated for the determination of glucosamine (GlcN) hydrolyzed from chitin in insect materials. The method was applied for quantifying the chitin content in mealworms (Tenebrio molitor) and crickets (Acheta domesticus). A baseline separation was obtained using an Acquity HSS T3 C18 column, with an external calibration curve of excellent linearity, and a low limit of detection and quantification of GlcN. Even though the recovery of GlcN from spiked cricket material was slightly lower compared to that using spectrophotometric method, the UPLC/FLR method proved a sensitive and specific method of quantification of insect chitin. Chitin contents in T. molitor and A. domesticus were 4.6 ± 0.1% and 4.5 ± 0.0% on dry matter basis, respectively. Less than 0.01% of chitin was present in insect protein-enriched fractions extracted with 0.1 N NaCl at pH 10.
为了避免因几丁质结合的氮而高估粗蛋白，需要精确量化昆虫几丁质。本文优化并验证了一种用于测定昆虫材料中几丁质水解的葡糖胺（GlcN）的 UPLC/FLR 方法。该方法应用于定量测定黄粉虫（Tenebrio molitor）和蟋蟀（Acheta domesticus）中的几丁质含量。使用 Acquity HSS T3 C18 柱获得基线分离，外部校准曲线具有极好的线性，GlcN 的检测限和定量限较低。尽管与使用分光光度法相比，从添加蟋蟀材料中回收的 GlcN 略低，但 UPLC/FLR 方法证明是一种灵敏且特异的昆虫几丁质定量方法。T. molitor 和 A. domesticus 的几丁质含量分别为干物质基础上的 4.6±0.1%和 4.5±0.0%。用 0.1N NaCl 在 pH 10 下提取的富含昆虫蛋白质的部分中，几丁质含量低于 0.01%。
