Table_1_Formation of Nε-Carboxymethyl-Lysine and Nε-Carboxyethyl-Lysine in Pacific Oyster (Crassostrea gigas) Induced by Thermal Processing Methods.DOCX

Advanced glycation end products (AGEs) are important endogenous hazardous substances produced during the thermal processing of foods, which have attracted much attention due to the potential health risks. The current research first investigated the effect of different thermal processing methods (steaming, boiling, sous vide (SV), and sterilizing) on the formation of two typical markers of AGEs, including Nε-carboxymethyl-lysine (CML) and Nε-carboxyethyl-lysine (CEL), in Pacific oyster (Crassostrea gigas). The compositions, lipid oxidation, di-carbonyl compounds, and AGEs in 12 kinds of processed oysters were detected, and the Index values (total Z-score) were calculated. The SV treatment at 70°C caused higher processing yield and lower CEL level while sterilizing in oil at 121°C greatly resulted in the formation of CML. The Index value of SV-treated oysters was much lower than steamed, boiled, and sterilized ones. Correlation analysis showed that the CML and CEL levels were positively correlated with fat content, a* and b* value (p < 0.05), and negatively correlated with moisture content and L* value (p < 0.05). Besides, thiobarbituric acid reactive substances had a negative correlation with CML (r = −0.63, p < 0.05) while no significant correlation with CEL (p > 0.05), suggesting that lipid oxidation had a greater effect on the formation of CML but less on the formation of CEL. In summary, SV treatment at 70°C within 15 min was a recommended thermal processing method to reduce the formation of AGEs in oysters.

晚期糖基化终末产物（advanced glycation end products, AGEs）是食品热加工过程中产生的重要内源性有害成分，因其潜在健康风险而受到广泛关注。本研究首先探究了不同热处理方式（清蒸、水煮、低温慢煮（sous vide, SV）以及灭菌处理）对太平洋牡蛎（Crassostrea gigas）中两种晚期糖基化终末产物典型标志物——Nε-羧甲基赖氨酸（Nε-carboxymethyl-lysine, CML）与Nε-羧乙基赖氨酸（Nε-carboxyethyl-lysine, CEL）生成量的影响。对12组不同处理的牡蛎样品的成分组成、脂质氧化水平、二羰基化合物含量以及晚期糖基化终末产物水平进行了检测，并计算了其综合指数值（总Z评分）。70℃低温慢煮处理可获得更高的加工得率，且CEL水平更低；而121℃油浴灭菌处理则显著促进了CML的生成。经低温慢煮处理的牡蛎样品的综合指数值显著低于清蒸、水煮及灭菌处理组样品。相关性分析结果显示，CML与CEL的含量与脂肪含量、红度值（a*）及黄度值（b*）呈显著正相关（p < 0.05），与水分含量及亮度值（L*）呈显著负相关（p < 0.05）。此外，硫代巴比妥酸反应物水平与CML含量呈显著负相关（r = -0.63，p < 0.05），但与CEL含量无显著相关性（p > 0.05），这表明脂质氧化对CML的生成影响更大，而对CEL的生成影响相对较小。综上，15分钟内70℃低温慢煮处理是可降低牡蛎中晚期糖基化终末产物生成量的推荐热处理方式。