Développements récents en matières de raffinage et de modifications : élimination des contaminants dans les huiles alimentaires et réduction du taux d’acides gras trans

Abstract

As a result of the general concern for food safety, the removal of minor contaminants (PAH, pesticides, dioxins, PCB’s…) from oils and fats has the be examined in detail. Also, in recent years a lot of attention has been given to the lowering of the trans fatty acids content in oils and fats for food products; the reason for this move is the potential negative health impact of trans fatty acids.In general, contaminants can be removed either during neutralization, by adsorption on activated carbon or during the deodorization process. To reach an efficient removal, the process conditions applied need to be optimised to achieve almost complete detoxification but with minimal costs.Traditionally, partially hydrogenated fats were used in nearly all food products because of their interesting melting properties. Nowadays, these products are replaced by trans free alternatives in most food products (margarines, bakery products…).This has created renewed interest for other modification processes: multiple dry fractionation and chemical and enzymatic interesterification. The challenge is to produce trans free fats with the same functionality as the trans rich products, but at comparable cost.