Oxidative Stability of α-Linolenic Acid in Corn Chips Enriched with Linseed Oil Pro/Antioxidative Activity of Tocopherol

Abstract

Extruded products, particularly those which are corn-based, are widely consumed salty or sweet snacks; moreover, they very often provide a basis for breakfast for people around the world. Extruded products are characterised by a low nutritional value, and a particularly low content of polyunsaturated fatty acids of the n-3 group. An attempt was made to enrich extruded corn crisps with α-linolenic acid (ALA) through the addition of refined linseed oil at an amount of 5 %. Corn crisps were produced with the addition of the oil concerned so that the concentration of ALA in the finished product was at least 2 g 100 g-1 (in a portion). With such a content of ALA, the crisps may be classified as 'functional food' in accordance with Commission Regulation (EU) No 432/2012 of May 2012. The following were tested: oxidative stability, and changes to the content of ALA during 6-month storage of crisps with the addition of linseed oil and various concentrations of δ-tocopherol and ascorbic acid. The crisps were packed in polyamide/polyethylene barrier film packages (30/70 μm), using either atmospheric air of argon for the packaging process. The study showed that with each applied concentration of δ-tocopherol added to the linseed oil (200-800 mg 100 g-1), it had a strong pro-oxidant effect. Packaging in argon atmosphere play very protective role in ALA stabilisation in functional corn crisp.