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ABSTRACT The oxidative stability of linseed (L), cotton (A), and coconut (C) oils, as well as of linseed:cotton (LA), linseed:coconut (LC), and linseed:cotton:coconut (LAC) compound oils was evaluated under accelerated storage at 60°C/20 days. Coconut oil showed to be rather stable, mainly due to low levels of peroxides, conjugated dienes, ρ-anisidine, and long induction period. In addition, along with cotton oil, it improved the stability of linseed oil in the formulation of LAC compound oil. As to fatty acid profile, the compound oils showed to be composed mainly by unsaturated fatty acids. Cotton and coconut oils presented higher retention of total phytosterols, 78.87 and 76.16%, respectively, after 20 days of storage, when compared to linseed oil. The highest retention of total tocopherols at the end of storage was observed in LA (90.81%). In relation to antioxidant activity, by the DPPH method, with the increase in storage time, a reduction in the antioxidant substances of linseed, LC, and LAC oils was observed. Through the FRAP method, oscillations were observed, especially in linseed and compound oils. Although the oils were degraded over time, it was possible to verify that cotton and coconut oils contributed to increase the stability of linseed oil, which, in turn, raised the levels of coconut oil bioactive compounds.

The aim of this study was to determine the chemical composition -physico-chemical properties, fatty acid and tocopherol compositions and total phenolic compounds -and evaluate the radical-scavenging activity of crude oil extracted from passion fruit (Passiflora edulis f. flavicarpa) seeds, aiming to use the agro-industrial by-products. The oil seed extraction was performed by Soxhlet method and the oil yield from the seeds was 30.39%. The oil showed high levels of unsaturated fatty acids (87.59%), including mainly linoleic (73.14%) and oleic (13.83%) acids, tocopherol (499.30 mg/kg) and phenolic compounds (1,314.13 mg GAE/kg). The physico-chemical characteristics were similar to those of other edible oils and the oil showed significant antioxidant activity. Therefore, the potential utilization of the passion fruit seed oil as a raw material for food, chemical and pharmaceutical industries could be favorable.

Abstract The present study aims to evaluate the influence of extraction methods on the quality of bioactive compounds and antioxidant capacity in Pterodon emarginatusVogel (sucupira) oils. The oils were extracted from the sucupira seeds by Soxhlet and by the extraction system of Bligh & Dyer. The oils were analyzed as to fatty acid profile, tocopherols, phytosterols, carotenoids, total phenolics, and total antioxidant capacity. The extraction by Soxhlet showed better yield of total lipids and was more efficient to extract tocopherols, phytosterols, and carotenoids, besides presenting better antioxidant activity by DPPH•. However, this method showed insufficient capacity to extract the polar lipid components of the sample, as evidenced by the low results of total phenolic compounds. On the other hand, the Bligh & Dyer method preserved the fatty acid profile and was also effective to extract higher phenolic compounds content and presented superior antioxidant activity when assessed by FRAP, ABTS•+, and oxidative stability index.

Abstract Each year, the consumption of vegetable oils increases gradually. Some oils, such as chia, sesame, and quinoa, are consumed due to the nutritional properties and health promoters that have been recognized in their components. Based on this premise, the present study aimed to characterize chia (Salvia hispanica), sesame (Sesamum inducum), and quinoa (Chenopodium quinoa) oils, in order to enable their applications in the development of new food products. Chia oil presented higher degradation, as it stood out with higher amounts of free fatty acids (4.46%) and peroxide value (18.35 meq/kg). It is an oil that is rich in polyunsaturated fatty acids (75.47%), and, consequently, with high refractive index (1,475) and iodine value (192.86 g/100 g). Quinoa oil stood out for its higher oxidative stability (17.55 h) and higher amount of phenolic compounds (190.84 mg/100 g). Sesame and quinoa oils showed no significant difference for carotenoids, but sesame oil had higher content of total tocopherols (656.50 mg/kg). Thus, the oils can be used in technological processes and/ or in the formulation of new food products, in order to their increase the nutritional value.