Food Biotechnology Program, Faculty of Science and Technology, University Sains Islam Malaysia, Bandar Baru Nilai 71800, Malaysia.
Department of Animal Production and Biodiversity, Institute of Tropical Agriculture and Food Security, University Putra Malaysia (UPM), Serdang 43400, Malaysia.
Molecules. 2020 Oct 28;25(21):4978. doi: 10.3390/molecules25214978.
A diet containing cholesterol is an essential component of biological function; however, cholesterol oxidation products (COPs) remain a major public health concern. This study investigated the effects of cooking methods (boiling and frying) on the production levels of COPs in processed foods. Samples, as represented by minced beef, chicken sausages, and fish fillets, were subjected to different cooking methods followed by COP extraction using a saponification method. Then, six common COPs, 5α-cholest, α-epoxy, β-epoxy, 25-HC, triol, and 7-keto, were quantified by triple quadrupole gas chromatography-mass spectrometry (GS-MS/MS). A significantly high number of COPs were detected in minced meat, of which 7-keto and triol were detected as major oxidation products, followed by chicken sausages and fish fillets ( ≤ 0.05). Compared to boiling, frying generated significantly more COPs, specifically triol (0.001-0.004 mg/kg) and 7-keto (0.001-0.200 mg/kg), in all samples. Interestingly, cholesterol level was found to be slightly (but not significantly) decreased in heat-treated samples due to oxidation during cooking, producing a higher number of COPs. Notably, the fish fillets were found to produce the fewest COPs due to the presence of a low amount of cholesterol and unsaturated fatty acids. In conclusion, adapting boiling as a way of cooking and choosing the right type of meat could serve to reduce COPs in processed foods.
含有胆固醇的饮食是生物功能的重要组成部分；然而，胆固醇氧化产物（COPs）仍然是一个主要的公共卫生关注点。本研究调查了烹饪方法（煮沸和油炸）对加工食品中 COPs 产生水平的影响。以绞碎牛肉、鸡肉香肠和鱼片为例的样品，采用不同的烹饪方法，然后用皂化法提取 COP。然后，通过三重四极杆气相色谱-质谱联用仪（GS-MS/MS）定量了六种常见的 COPs，即 5α-胆甾烷、α-环氧化物、β-环氧化物、25-HC、三醇和 7-酮。在绞碎的肉中检测到大量的 COPs，其中 7-酮和三醇是主要的氧化产物，其次是鸡肉香肠和鱼片（≤0.05）。与煮沸相比，油炸在所有样品中产生了更多的 COPs，特别是三醇（0.001-0.004mg/kg）和 7-酮（0.001-0.200mg/kg）。有趣的是，由于烹饪过程中的氧化，热处理样品中的胆固醇水平略有（但不显著）降低，产生了更多的 COPs。值得注意的是，由于胆固醇和不饱和脂肪酸含量较低，鱼片产生的 COPs 最少。总之，采用煮沸作为烹饪方式并选择合适类型的肉可以减少加工食品中的 COPs。
