Physicochemical characteristics, oxidative stability, pigments, fatty acid profile and antioxidant properties of co-pressed oil from blends of peanuts, flax seeds and black cumin seeds

Authors: SURI, KANCHAN - Guru Nanak Dev University; SINGH, BALWINDER - Khalsa College; KAUR, AMRITPAL - Guru Nanak Dev University; Yadav, Madhav

Submitted to: Food Chemistry Advances
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/6/2023
Publication Date: 3/15/2023
Citation: Suri, K., Singh, B., Kaur, A., Yadav, M.P. 2023. Physicochemical characteristics, oxidative stability, pigments, fatty acid profile and antioxidant properties of co-pressed oil from blends of peanuts, flax seeds and black cumin seeds. Food Chemistry Advances. https://doi.org/10.1016/j.focha.2023.100231.
DOI: https://doi.org/10.1016/j.focha.2023.100231

Interpretive Summary: Extraction of oil from a blend of seeds is a novel approach to improve the stability and nutritional qualities of the oil. Thus, in order to improve the chemical properties, oxidative stability, heat stability, and the desired nutritional values of vegetable oil, we tested extracting it from blends of peanut, black cumin and flax seeds. The black cumin seeds and flaxseeds are rich in bioactive compounds, pigments, and good fatty acids. Blending these two oilseeds with peanuts prior to oil extraction, showed a significant improvement in its stability and nutritional qualities over unblended peanut oil. By increasing the amount of black cumin seeds blended with peanuts from 10 to 40% increased the oil’s oxidative stability index, total phenolic content, chlorophylls and carotenoids content. By increasing the level of flax seeds blended with peanuts from 10 to 40% increased the acid value, polyunsaturated fatty acids content and improved other heart healthy components of the oil. Overall, we found that blending 60% peanuts, 20% black cumin seeds and 20% flax seeds gave the oil with the highest oxidative stability and the nutritional qualities.

Technical Abstract: Extracting an edible oil from blends of oilseeds (premixed in different ratios) is a novel approach for improving its nutritional qualities and stability. In this study, raw peanut seeds (PS), premixed with black cumin seeds (BS) and flaxseeds (FS) at 10, 20, 30 and 40% levels (individually or collectively) were co-pressed (CP) to obtain edible oils. The oil yield, physicochemical properties, oxidative stability index (OSI), total phenolic (TPC), chlorophyll content (ChC) and carotenoid content (CaC), radical scavenging activity (RSA), fatty acid composition, '6/'3 ratio, atherogenicity (AI) and thrombogenicity (TI) indices of twelve oils obtained by co-pressing (CP-1 to CP-12) seed mixtures were investigated and compared. As the proportion of BS during its premixing with PS was increased from 10 to 40%, the OSI and RSA increased and the oil became darker in colour due to an increase of ChC, CaC and TPC. The polyunsaturated fatty acid content, AI, TI and '6/'3 ratio was improved by increasing the proportion of FS (from 10 to 40%), during its premixing with PS. The co-pressing of 20% BS and 20% FS collectively with PS (CP-10) improved the AI, TI, OSI and '6/'3 ratio of oil. These results suggest that the BS and FS can be premixed with PS for obtaining a co-pressed oil with a better OSI, fatty acid profile, balanced '6:'3 ratio and high nutritional qualities.