Wheat bran is an important source for human and animal feed. Its nutritional aspects include a high content of fibre and minerals, as well as phenolic compounds that help prevent chronic diseases. However, wheat can be susceptible to contamination by fungus, which can produce mycotoxins such as deoxynivalenol (DON) and zearalenone (ZEN), causing adverse health effects. Therefore, methods should be developed to reduce possible contamination. Ozone can be used for this purpose as it is considered safe and environmental friendly. The aim of this study was to evaluate the reduction of DON and ZEN concentrations in wheat bran using the ozonation process as well as to evaluate the effect of ozonation on the nutritional quality of bran. Considering this, wheat bran naturally contaminated with both DON and ZEN was processed using ozone at different conditions. The nutritional quality of the bran was evaluated after processing considering the following aspects: the total phenolic content and the bran antioxidant capacity (by using both DPPH and ABTS radicals). The results showed that the degradation of ZEN was higher and faster than the degradation of DON, which could be explained by their molecular structures. The total phenolic content and antioxidant capacity of the bran were not affected by the ozonation process, which is preferable from a nutritional point of view. Therefore, ozonation was demonstrated to be a possible method for reducing mycotoxins in wheat bran, although more studies are needed in order to better understand and optimise processing and product quality.
Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached-deodorized (RBD) soybean oil. The oxidative stability of the oil samples was determined using the Oil Stability Index method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. All extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Oil Stability Index method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT. The present study confirmed that gamma radiation did not affect the peanut skin extracts’ antioxidative properties when added to soybean oil.
Peels and seeds are the primary by-products of the passion fruit agroindustry. This study was designed to evaluate the potential of passion fruit peel and seeds flour (PFF) as a source of fiber and minerals to enhance the functional properties of drinkable yogurt. Proximate composition, mineral content, technological (pH, viscosity, color, and syneresis), and microbiological analyses (lactic acid bacteria, as well as yeast and mold counts), acceptance test, descriptive sensory analysis, and shelf life assessments were analyzed. Drinkable yogurts fortified with PFF showed higher fiber levels (both soluble and insoluble) and mineral content (potassium, magnesium, and manganese). Incorporation of PFF increased the viscosity and promoted changes in the color parameters of yogurts. During storage, the pH and the number of viable lactic acid bacteria decreased while the syneresis and yeast and mold counts increased. The shelf life of drinkable yogurts was estimated to be 21 days. Regarding sensorial aspects, drinkable yogurt fortified with 2% of PFF was considered the most viable product for market exploitation. The present contribution indicates that the use of passion fruit by-products in the development of drinkable yogurts is a viable alternative which can be explored for nutritional, technological, and sensory purposes by the food industry.