Potential factors that influence the occurrence of trans fatty acids in fried foods: a case study on plantain chips sold within the Accra Metropolis, Ghana

Abstract

Dietary trans fatty acids (TFAs) are largely unregulated in Ghana despite known health risks. However, data on TFA levels in Ghanaian foods, especially in deep-fried snacks, are lacking, even though suboptimal frying, a common practice among food vendors, may contribute to TFA formation. This study assessed the TFA content in plantain chips, a popular deep-fried snack, using gas chromatography with a flame-ionizing detector (GC-FID) to fill this knowledge gap. A total of 120 plantain chip samples were statistically acquired from various processors and vendors in the Accra Metropolis, and the total fat and TFA concentrations were quantified. Additionally, a survey was conducted on 30 commercial plantain chip processors via in-depth interviews. The fat content of the plantain chips ranged from 26.0 g to 30.9 g/100 g, with TFA concentrations varying between 1.41 g and 2.88 g/100 g fat and 0.41 g and 0.78 g/100 g food. Seven trans isomers of oleic acid (OA), linoleic acid (LA), and alpha-linolenic acid (ALA) were detected in all the food samples, at varying concentrations. The specific isomers identified included one from OA (t9-C18:1), two from LA (c9, t12-C18:2; t9, c12-C18:2), and four from ALA (c9, c12, t15-C18:3; c9, t12, t15-C18:3; c9, t12, c15-C18:3; t9, c12, c15-C18:3; and t9, c12, c15-C18:3). Almost all (97%) commercial plantain chip processors admitted to reusing oils four or more times before disposal and reported using different types of oils, primarily refined, bleached deodorized palm olein and soybean-based oils. The reuse of oils and the types of oil used were identified as contributing factors influencing TFA occurrence in the snack. Stricter regulations on oil usage in food processing are needed to minimize TFAs in Ghanaian foods.