The increase of atherogenic index on fatty acids composition as a consequence of trans fat acids reduction in industrialized foods: the Brazilian scenery

Abstract The use of fats with a low melting point is attractive to the food industry, as it contributes to improving the texture, color and stability characteristics of the food. These fats are obtained from vegetable oils through some processes such as hydrogenation or interesterification. However, the partial hydrogenation process leads to the formation of trans fat. In several countries, actions have been taken to eliminate the presence of elaidic acid, a trans fatty acid (C18: 1t) from processed foods. This trans fatty acid and palmitic acid, a common saturated fatty acid (C16: 0) are proven to be atherogenic. The aim of this work was to evaluate the composition of fatty acids of 39 types of commercialized foods in Brazil, including cookies, snacks, wafers, instant noodles, frozen sandwiches and pizzas, mixtures for food preparation, microwave popcorn, margarines, spreadable cheeses and pastry dough. The lipids were extracted and their Fatty Acid Methyl Esters (FAMEs) identified by Gas-Chromatography (GC). The fatty acids found in greater quantity were oleic, linoleic and palmitic acids; whereas the trans fatty acids were detected in 51.3% of the samples. On the other hand, when trans fast were reduced in some foods, it could be observed increases in the palmitic acid (C16:0) content. This high content of palmitic acid is justified by the addition of palm oil and its derivatives, which can be used in interesterified oil mixtures or can be directly used in industrialized food formulations, even without interesterification. Governments and organizations in favor of human health should be aware that the use of dietary fatty acids which compromise the atherogenic index is not a healthy alternative. Consumers should therefore be alerted to the risk of consuming foods containing these fats until the food industry is banned from using them or finds healthier alternatives for making food.

摘要 低熔点油脂在食品工业中极具应用价值，因其可有效改善食品的质地、色泽与稳定性能。此类油脂多通过氢化或酯交换等工艺从植物油中制取。然而部分氢化工艺会产生反式脂肪。目前多国已采取措施，旨在去除加工食品中的反油酸（elaidic acid）——一种反式脂肪酸（trans fatty acid，C18:1t）。研究证实，该反式脂肪酸与常见饱和脂肪酸棕榈酸（palmitic acid，C16:0）均具有致动脉粥样硬化性。本研究旨在分析巴西市场在售的39种食品的脂肪酸组成，涵盖曲奇、零食、威化饼、方便面、冷冻三明治与披萨、食品制备预拌粉、微波爆米花、人造奶油、涂抹型奶酪及酥皮面团。采用萃取法提取脂质，通过气相色谱（Gas-Chromatography，GC）鉴定其脂肪酸甲酯（Fatty Acid Methyl Esters，FAMEs）。检出含量较高的脂肪酸为油酸、亚油酸与棕榈酸；另有51.3%的样品中检测到反式脂肪酸。此外，部分食品中反式脂肪酸含量降低时，其棕榈酸（C16:0）含量会相应升高。该棕榈酸含量偏高的原因在于添加了棕榈油及其衍生物——此类物质既可用于酯交换油脂混合物，也可直接应用于工业化食品配方，无需经过酯交换工艺。各国政府与关注人类健康的相关组织应意识到，使用会升高致动脉粥样硬化指数的膳食脂肪酸并非健康之选。因此，需提醒消费者注意食用此类含脂食品的健康风险，直至食品工业彻底禁用此类油脂或研发出更健康的替代方案。