Enrichment of soybean oil with carotenoids from chili paste by-product: enhancement of quality, oxidative stability, and thermo-resistance.

Soybean is one of the most important crops worldwide, providing vegetable oil that is usually used in domestic and industrial food preparations. However, due to its high unsaturated fatty acid content, it is subjected to significant thermal oxidation and degradation. For this, the present study aims to improve the thermo-stability (170 °C for 10 h/day for 5 days) of refined soybean oil by enrichment with carotenoids of chili by-product as natural antioxidants at different concentrations (0.05, 0.2, and 0.5 ppm) in comparison to soybean oil supplemented with β-carotene at similar concentrations (positive control) and oil without any addition (negative control). The quality assessment of soybean oil, physicochemical parameters, and oxidation degree were assessed before and after heat treatment. The effect on the fatty acids profile was also carried out by gas chromatography coupled with flame ionization detector (GC-FID). According to the results registered during different steps of heat treatment, it was revealed that the enrichment of soybean oil with carotenoids enhanced the quality characteristics and reduced the oxidation incidence. More interestingly, the supplementation of refined soybean oil with 0.5 ppm of carotenoids was significantly able to reduce oxidation, giving soybean oil the best thermo-stability improvement. In addition, the carotenoids allowed more protection of fatty acids, particularly linoleic and linolenic acids, after heat treatment. The carotenoids from chili by-product represent a good source of natural bioactive compounds that could be used to enhance the thermal stability of refined soybean oil. [ABSTRACT FROM AUTHOR]