Evaluation of grain and oil quality of packaged and ozonized flaxseed

Abstract Flaxseed (Linum usitatissimum L.), high in substances with functional properties, depends on good practice for assuring the post-harvest quality and maintenance of its nutritional properties. This study evaluated the effect of ozonation and two types of packaging on the grains and oil quality of brown and golden flaxseed stored. The freshly harvested grains were kept in three different conditions viz. control, polyethylene-coated paper packaging and polypropylene plastic packaging for 90 days at room temperature (21 ± 2 °C), with four replicates of 1.5 kg. Ozone injection occurred within a 110 m³ room containing the packages at 10 ppm for 120 min. The results showed that ozonation on different types of packaging and storage did not influence the moisture content of the grains and index peroxide on flaxseed oil. The golden flaxseed variety showed an increase in free fatty acids after storage, as well as mean values for higher fungi count than those of brown flaxseed, indicating higher contamination. The packaging influenced the lipid content for both varieties studied, and, for brown flaxseed, the polyethylene-coated paper packaging showed better maintaining of quality after storage. The type of packaging influenced the color parameters only before of the storage, i.e., instants after ozone application, and the polyethylene-coated paper packaging presented color values similar to the control, indicating that exposure to the ozone gas did not alter the grains. Thus, polyethylene-coated paper packaging showed better conservation of lipids and maintenance of color parameters. Further studies are desirable to determine the appropriate package for the ozonation process and storage of golden flaxseed.