Composition and oxidative stability of oil from Salvia hispanica L. seeds in relation to extraction method

Abstract

This study evaluated the influence of the extraction method on the composition, quality and oxidation stability of chia seed oil. Commercial chia seeds were purchased from a local market and oils were obtained using various methods: Classical Soxhlet extraction using hexane and acetone, supercritical fluid extraction with CO2 at 70 and 90°C, and screw‐pressing from native seeds (cold process), and from seeds conditioned at 110°C (hot process). The oils were characterized by their contents of sterols, tocochromanols, phenolic compounds, carotenoids and squalene, acid and peroxide values and induction times. It was found that the method of obtaining oil had an influence on the extraction of components and oxidative stability. The most favorable method was classical extraction with acetone. This solvent was the most effective in the extraction of total lipids and bioactive components, especially phenolic compounds and carotenoids. The content of these components was highly correlated with induction time. The recovery of oil was generally lower by pressing than by extraction methods and the content of sterols and phenolic compounds was also reduced. In turn, fluid extraction at 70°C was effective in the extraction of squalene and the quality of oil extracted by this method was comparable to cold pressed oil. Practical applications: Chia seeds contain a large amount of oil (from 25 to 35%), which is rich in polyunsaturated fatty acids, mainly α‐linolenic and linoleic acids, with share of ca. 60–67% and 20%, respectively. The high content of PUFA makes this oil very susceptible to oxidation. The seeds are also abundant in many phytochemicals (sterols, tocopherols, squalene, waxes, carotenoids, and phenolics), but their extractivity to the oil depends on the processing conditions. In the study, we evaluated the composition and stability of chia seed oils obtained by classical solvent extraction, supercritical fluid extraction with CO2 and screw‐pressing. It was shown that the most favorable method was the extraction with acetone. This solvent was the most effective in extraction of total lipids and bioactive components, especially phenolic compounds and carotenoids. Oil obtained by extraction with acetone was additionally characterized by the highest oxidative stability. This information may be of support to producers for obtaining chia oil more stable and with better nutritional and nutraceutical properties. Oil obtained by extraction with acetone is very different from other oils considering the quality, stability, and contents of bioactive compounds.

Application of a novel approach to modelling the supercritical extraction kinetics of oil from two sets of chia seeds

“…2b) were very similar (PUFA and ALA concentrations around (81% and 59%, respectively). Our results agree well with those of other authors, who used chia seeds from several geographical origins, and applied different extraction methods and operational conditions [7][8][9][10][11][17][18][19][20].…”

“…Thus far, different solvents (ethyl acetate, acetone, propane, petroleum ether and hexane) and extraction techniques (cold and hot pressing, Soxhlet, Ultrasound-Assisted Extraction and Pressurized Liquid Extraction) have been applied to obtain chia seed oil [7][8][9][10][11]. A viable and eco-friendly alternative to the use of organic toxic solvents is the extraction with supercritical CO 2 (scCO 2 ), which is non-toxic, non-flammable, non-mutagenic and carcinogenic and is abundant and inexpensive.…”

Extraction Technology Can Impose Influences on Peanut Oil Functional Quality: A Study to Investigate the Lipid Metabolism by Sprague–Dawley Rat Model

“…The CP technology has been considered as an ideal edibleoil-producing method, because it can produce high-quality products without high temperature or chemical treatment. As reported in previous studies, compared with the HP methods, the chia seed oil derived from the CP technology contained significantly higher tocopherols and squalene (Dąbrowski, Konopka, Czaplicki, & Tańska, 2017;Duthie, Crozier, & Goldberg, 2003), which might imply that the consumption of the cold-pressed oils was good for human's health. However, several studies claimed that the polyphenol compounds (PC), and some other minor components, such as total tocopherols (TTCs), in hot-pressed oil were higher than Investigation on lipid metabolism by Sprague-Dawley rat model .…”

“…CPO contained higher TTC and PC than HPO and EAO ( P < 0.05), which suggested that cold process technology might protect this kind of bioacitive component. A recent study showed that compared with hot press methods, cold press technology could preserve squalene in Salvia hispanica L. seed oil (Dąbrowski et al., ). Moreover, Nakić et al.…”

“…CPO contained higher TTC and PC than HPO and EAO (P < 0.05), which suggested that cold process technology might protect this kind of bioacitive component. A recent study showed that compared with hot press methods, cold press technology could preserve squalene in Salvia hispanica L. seed oil (Dąbrowski et al, 2017). Moreover, Nakić et al (2006) reported that pumpkin seed oil extracted by Soxhlet apparatus at a temperature below 70°C contained significantly higher squalene than the pumpkin seed oil prepared by roasting process at a temperature from 100 to 130°C.…”