College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China.
Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.
J Agric Food Chem. 2024 Aug 28;72(34):19177-19186. doi: 10.1021/acs.jafc.4c04019. Epub 2024 Aug 14.
The common presence of glycidyl esters (GEs) in refined vegetable oils has been a concern for food safety. The present study aimed to investigate the inhibitory effects of three carotenoids derived from microalga on GE formation in both rice oil and a chemical model during heating. The addition of astaxanthin (AS), lutein (LU), and β-carotene (CA) at 0.6 mg/g in rice oil can reduce GE formation by 65.0%, 57.1%, and 57.5%, respectively, which are significantly higher than those achieved by common antioxidants such as l-ascorbyl palmitate (39.0%), α-tocopherol (18.5%), -butyl hydroquinone (42.7%), and quercetin (26.2%). UPLC-Q-TOF-MS/MS analysis showed that two new compounds, that is, propylene glycol monoester and diester of palmitic acid, were formed in the CA-added chemical model, which provided direct experimental evidence for the inhibition of antioxidants including AS, LU, and CA against GE formation not only by indirect antioxidative action but also by direct radical reactions to competitively prevent the formation of cyclic acyloxonium intermediates. Furthermore, it was interestingly found that only AS could react with the GEs. The adduct of AS with GEs, astaxanthin-3-O-propanetriol esters, was preliminarily identified using Q-TOF-MS/MS in the heated AS-GE model, suggesting that reacting with GEs might represent another distinct mechanism of AS to eliminate GEs.
精炼植物油中普遍存在缩水甘油酯（GEs），这引起了人们对食品安全的关注。本研究旨在探讨三种源自微藻的类胡萝卜素对加热过程中稻米油和化学模型中 GE 形成的抑制作用。在稻米油中添加 0.6mg/g 的虾青素（AS）、叶黄素（LU）和β-胡萝卜素（CA），可分别使 GE 形成减少 65.0%、57.1%和 57.5%，显著高于棕榈酸抗坏血酸酯（39.0%）、α-生育酚（18.5%）、-叔丁基对苯二酚（42.7%）和槲皮素（26.2%）等常见抗氧化剂的抑制效果。UPLC-Q-TOF-MS/MS 分析表明，在添加 CA 的化学模型中形成了两种新化合物，即丙二醇单酯和棕榈酸二酯，这为 AS、LU 和 CA 等抗氧化剂不仅通过间接抗氧化作用，而且通过直接的自由基反应来抑制 GE 形成提供了直接的实验证据，从而竞争性地阻止环状酰氧鎓中间体的形成。此外，有趣的是发现只有 AS 可以与 GEs 发生反应。在加热的 AS-GE 模型中，使用 Q-TOF-MS/MS 初步鉴定了 AS 与 GEs 的加合物，虾青素-3-O-丙三醇酯，这表明与 GEs 反应可能是 AS 消除 GEs 的另一种独特机制。
