Some Chemical Characteristics and Oxidative Stability of Cold Pressed Grape Seed Oils Obtained from Different Winery Waste

Abstract

Various grape seed samples collected in wineries, as a by‐product before and after the fermentation process of pomace and after fermentation and distillation process of pomace, are used for oil extraction by cold pressing. Fatty acid profile, content and composition of tocopherols, content and composition of phenols, as well as the oxidative stability of oils are investigated. Obtained results show that cold pressed grape seed oils are characterized by different nutritional quality and oxidative stability, due to peculiar effects of the fermentation and distillation processes. Cold pressed oil obtained from cleaned and dried seeds of grapes after fermentation and/or distillation process is richer in bioactive compounds compared to the oil obtained from grape seeds without fermentation. On the other hand, the high temperature in distillation process of pomace has a negative effect on the content of some bioactive compounds and oxidative stability of oil from this waste material. Practical Applications: In this paper, different cold pressed grape seed oils are analyzed for nutritionally important compounds and oxidative stability. The results show that, depending on the source of grape seeds as waste material, the nutritional quality of the obtained oils differs. In the production of high quality cold pressed grape seed oil, seeds from different sources of waste should not be mixed. It is not recommended to use the seeds from the waste material after distillation process in the production of high quality cold pressed grape seed oil. Some chemical characteristics of cold pressed grape seed oils obtained from different winery waste are analyzed. The different waste materials have a pronounced effect on the quali‐quantitative profiles of bioactive compounds and induction period of oils. Obtained results show that cold pressed grape seed oils are characterized by different nutritional quality and oxidative stability, due to peculiar effect of fermentation and distillation processes. For production of high quality cold pressed oil, seeds from different winery waste material should not be mixed.

The Potential of Grape Pomace Varieties as a Dietary Source of Pectic Substances

“…The grape seeds are reported to contain about 3–6% of the total dry weight of grapes [ 85 , 86 ]. The grape seeds are reported to consist of 11% protein, 35% fiber, 3% minerals, 7% water [ 87 ], 7–20% lipids [ 20 , 88 , 89 , 90 ] and 7% phenolic compounds [ 30 ], tocopherols and β-carotene which are found in grape seed oil. Licev et al [ 91 ] have been reported that grape seeds consist of 25–45% water, 34–36% oil, 4–6% tannins, 2–4% phenolic substances, 4–6% nitrogen compounds, 2–4% minerals, 10–11% cellulose, 8–10% pentosans and 25–28% lignin, but Cotea [ 92 ] has been noted that grape seeds includes 28–40% water, 28% cellulose, 0.8–1.2% nitrogen compounds, 4–6% tannins, 10–25% oil and 2–4% mineral substances.…”

“…Licev et al [ 91 ] have been reported that grape seeds consist of 25–45% water, 34–36% oil, 4–6% tannins, 2–4% phenolic substances, 4–6% nitrogen compounds, 2–4% minerals, 10–11% cellulose, 8–10% pentosans and 25–28% lignin, but Cotea [ 92 ] has been noted that grape seeds includes 28–40% water, 28% cellulose, 0.8–1.2% nitrogen compounds, 4–6% tannins, 10–25% oil and 2–4% mineral substances. The concentration of minority compounds may vary depending on the technological process, environmental and cultivar conditions [ 89 , 93 ].…”

In Vitro Digestion of Grape Seed Oil Inhibits Phospholipid-Regulating Effects of Oxidized Lipids

“…Additionally, single polyphenols were measured by high-resolution LC-MS (Table 2). Catechin, ferulic acid and p-coumaric acid were depicted as they are common polyphenols in grape seed oil [47,48]. It could be shown that these three polyphenols decreased mainly between zero and two hours of the in vitro digestion.…”

Impact of plum processing on the quality and oxidative stability of cold-pressed kernel oil

“…The increase in tocopherol content can be explained by the effect of alcohol during the fermentation process, which accelerates the separation of individual components, affecting primarily the porosity of the kernel. However, during distillation, although this process may continue, high temperatures cause degradation of the tocopherols and decrease their content (Bjelica et al, 2019). The β+ɣtocopherol were dominant in all oil samples, with 48.5 mg•100g -1 in PKBF, while in oil samples from PKAF and PKAD, this tocopherol homologues were represented by 57.7 and 56.4 mg•100g -1 , respectively.…”