Chinese Academy of Inspection and Quarantine, Beijing 100176, People's Republic of China.
College of Food Engineering, Ludong University, Yantai 264025, People's Republic of China.
J Agric Food Chem. 2022 Aug 3;70(30):9442-9450. doi: 10.1021/acs.jafc.2c01617. Epub 2022 Jul 12.
Sesame can trigger a systemic allergic reaction. In the present study, we investigated the responses of the structure and IgE binding of sesame allergens to different roasting treatments (120, 150, and 180 °C for 5 to 30 min). We analyzed the tryptic digestion peptides using a label-free mass spectrometry method. The total amount of soluble proteins in sesame was significantly reduced by roasting at 180 °C, followed by 150 °C. Ses i 1 was the most stable protein during processing as it still possessed a higher protein abundance compared to other allergens after roasting under 180 °C. The most unstable allergens were Ses i 4 and Ses i 7, which suffered severe protein degradation at 180 °C. Roasting at 180 °C remarkably increased the secondary structure content of α-helices but decreased that of β-sheets, whereas roasting at 120 and 150 °C had a limited effect on the secondary structure of sesame proteins. Moreover, serum pool Western blot analysis showed that the main allergens were oleosin of Ses i 4 and Ses i 5. The IgE-binding ability of sesame allergens was significantly decreased under 180 °C roasting, as well as the solubility of sesame proteins, which showed remarkable congruence in changes. Relative quantification results indicate that individual sesame allergens respond differently to the roasting process. In general, sesame allergens are unstable under roasting treatment. Therefore, the allergenic potential of sesame allergens may be minimized by selecting appropriate parameters during processing.
芝麻可能引发全身性过敏反应。在本研究中，我们研究了芝麻过敏原的结构和 IgE 结合对不同烘焙处理（120、150 和 180°C 烘烤 5 至 30 分钟）的响应。我们使用非标记质谱法分析了酶解肽。在 180°C 下烘烤会显著降低芝麻中的可溶性蛋白质总量，其次是 150°C。Ses i 1 是加工过程中最稳定的蛋白质，因为与其他过敏原相比，它在 180°C 下烘烤后仍具有较高的蛋白质丰度。最不稳定的过敏原是 Ses i 4 和 Ses i 7，它们在 180°C 下会遭受严重的蛋白质降解。180°C 烘烤显著增加了 α-螺旋的二级结构含量，但降低了 β-折叠的含量，而 120 和 150°C 对芝麻蛋白的二级结构影响有限。此外，血清池 Western blot 分析表明，主要过敏原是 Ses i 4 和 Ses i 5 的油蛋白。180°C 烘烤下芝麻过敏原的 IgE 结合能力显著降低，芝麻蛋白的溶解度也显著降低，两者的变化具有显著的一致性。相对定量结果表明，个别芝麻过敏原对烘焙过程的反应不同。总体而言，芝麻过敏原在烘焙处理下不稳定。因此，通过在加工过程中选择适当的参数，可以最大限度地降低芝麻过敏原的致敏潜力。
