Blends of Cold Pressed Black Cumin Oil and Sunflower Oil with Improved Stability: A Study Based on Changes in the Levels of Volatiles, Tocopherols and Thymoquinone during Accelerated Oxidation Conditions

Abstract

Blends (5%, 10% and 20%, w/w) of cold-pressed black cumin (Nigella sativa) oil (BCO) with sunflower oil (SO) were formulated. Oxidative stability (OxS) of SO and blends during storage at thermal accelerated oxidation conditions including Rancimat method (110C) and Schaal oven test (60C) was studied. Progression of oxidation was followed by measuring peroxide value (PV), conjugated dienes (CD) and conjugated trienes (CT). Changes in the volatile oxidation compounds, thymoquinone and tocopherols levels of oils and blends during thermal oxidation were also recorded. Blending did not affect significantly the fatty acids profile of blends wherein linoleic and oleic acids were the main constituents. Inverse relationships were noted between PV and OxS at termination of storage. Levels of CD and CT in SO and blends increased with increase in time. Nine volatile oxidation compounds including hexanal, (E)-2-hexenal, 2-heptanone, (E)-2-heptenal, 1-octen-3-one, 1-octen-3-ol, (E)-2-octenal, (E,E)-2,4-octadienal and (E,E)-2,4-decadienal were identified using the headspace/solid phase microextraction-gas chromatography/mass spectrometry (HS/ SPME-GC/MS). Hexanal and (E)-2-heptenal were predominant identified compounds wherein these compounds increased during oxidation at 60C. Stability of blends was better than SO, most likely due to changes in the levels of thymoquinone and tocopherols' found in BCO. PRACTICAL APPLICATIONBlending of edible oils have emerged as an economical way of improving organoleptic and physicochemical characteristics of vegetable oils besides enhancement the oxidative stability. Among new sources of edible oils with high levels of bioactive compounds, cold pressed black cumin oil (BCO) is of interest and may play a role in human health. At different levels of blending SO with BCO, the stability of sunflower oil (SO) was enhanced. The optimal level of BCO enrichment will depend on the actual food application. It is expected that commercial exploitation of BCO:SO blends with affordable cost for consumers will be soon realized.Journal of Food Biochemistry 00 (2016) 00-00 V C 2016 Wiley Periodicals, Inc.

Oil/fat blending strategy for improving milk fat globule membrane stability and its effect on fatty acid composition

“…The palmitic, oleic and linoleic acids in the CEO represented the main fatty acids, accounting for 14.0, 23.9 and 57.3%, respectively. This result was in agreement with that of Kiralan et al (). In addition, Heidarian Miri et al () reported an increase in oleic acid content in milk from a lactating goat after supplementation with cumin seed extract.…”

“…Blending two or more oils can increase the fatty acid composition (Khusaibi et al ). However, the blending of sunflower oil with cold‐pressed black cumin improves the stability while maintaining the same fatty acids before and after blending (Kiralan et al ).…”

Design of flavonoid microparticles with channel forming properties to improve oxidative stability of sunflower oil

“…IP values of SO were higher than ML, both with and without flavonoid microparticles incorporated at the same concentration, which can be expected due to the antioxidant action of tocopherol in SO. It is well‐known that vegetable oils are natural sources of antioxidants such as tocopherols, which protect PUFA from oxidation and improve the oxidative stability of oils , being alpha‐tocopherol the most abundant isomer in SO .…”

Phytochemical Content, Oxidative Stability, and Nutritional Properties of Unconventional Cold-pressed Edible Oils

“…Black cumin oil showed the highest AV (15 mg KOH/g) and PV (58 meq O 2 /kg) ( Table 1). When Kiralan et al [22,23] determined the PV of fresh black cumin oil, the level of hydroperoxides was affected by the extraction method used and was lower (18-31 meq O 2 /kg). A high level of hydroperoxides was also detected in blackcurrant and poppy seed oils, amounting to 30 meq O 2 /kg for both.…”