Grape pomace and seeds, good source of functional compounds such as polyphenols, are waste by-products generated during wine making. Extraction is a very important step for later use of polyphenols. Herein we investigated the effects of conventional (CSE) and non-conventional extraction methods (subcritical water extraction (SWE) and pressurized ethanol extraction (PEE) on extraction yield, total phenolic content (TPC) and antioxidant capacity (AC) of Black Borgoña (Vitis labrusca L.) grape, pomace and seeds. Chemical composition showed the greatest amount of protein and lipids in pomace and seeds. Calcium was present in a high concentration in seeds (137.24 mg/100 g DM). PEE samples retained the highest TPC among all the extraction methods for grape, pomace and seeds with 21.42 ± 0.43, 54.36 ± 3.37 and 56.5 ± 3.81 mg GAE/g DM, respectively. The highest AC was determined by FRAP in seeds, 431.16 ± 37.71 µmol TE/g DM, followed by 329.04 ± 13.3 µmol TE/g DM in pomace when PEE was used. Significant correlations between antioxidant capacity and total phenolics were observed for all samples. This study demonstrated that non-conventional green method PEE is an efficient method to achieve the highest TPC and AC of Black Borgoña grape, pomace and seeds.

The objectives of this study were to evaluate the effects of the grape cultivar geographical location and extraction technique on the total phenolic compounds (TPC), antioxidant capacity (AC), oil yield and quality of Quebranta (Vitis vinifera) grape seeds. Seeds were defatted with supercritical CO 2 and the bioactive compounds were extracted with subcritical water and macerations with methanol, ethanol, and acetone. The differences in grape seed oil yield were not significant (p > 0.05). The most abundant fatty acid determined was linoleic (66.37-67.37%). The highest TPC corresponded to the extracts from zones A and B obtained with subcritical water, 167.56 ± 10.40 and 161.83 ± 4.95 mg GAE/g dw, respectively. The highest AC by DPPH was also achieved by the extracts from zones A and B (1,479.90 ± 12.86 and 1,628.15 ± 80.32 µmol TE/g dw, respectively) with subcritical water extraction. The highest AC by FRAP was observed in the subcritical water extracts from zones B and C, 1,429.29 ± 29.75 and 1,389.54 ± 7.46 µmol TE/g dw, respectively. Grape seed is a valuable source of nutritionally oil and bioactive compounds, which can be obtained from by-products of pisco production for potential use in the food and pharmaceutical industries.

Proximal composition, dietary minerals, total phenolic compounds (TPC) and antioxidant capacity (AC) were quantified in Black Borgoña (BBGP) and Quebranta grapes pomace (QGP) from Chincha and Ica (Peru). TPC and AC of grapes seeds and oil were also investigated, as quality and fatty acids of the oil. The highest amount of protein was for QGP (Chincha) (13.29 ± 0.01 g/100 g dw) and lipids in BBGP (Ica) (13.67 ± 0.01 g/100 g dw). Fe in QGP (Chincha) (61.46 ± 2.76 mg/100 g dw) and Ca in BBGP (Ica) (424.24 ± 13.35 mg/100 g dw) were higher than in the other samples. The most abundant fatty acid was linoleic with 71.70 ± 0.01% in Black Borgoña grape seed oil (BBGSO) (Chincha). Highest TPC corresponded to Quebranta grape seeds (QGS) (Ica) (14.43 ± 0.75 mg GAE/100 g dw). The highest AC by DPPH and FRAP was achieved by QGS (Chincha) (1255.39 ± 61.45 µmol TE/g dw) and QGS (Ica) (960.77 ± 56.68 µmol TE/g dw), respectively. Differences in AC by ABTS for grape seed oil were not significant (p > 0.05). In conclusion, BBGP and QGP, seeds and oil showed an enormous potential for their application as functional additives in the food industry.

Grape seed oil, which is extracted with highly toxic organic solvents that are harmful to human health, is produced from tons of grape pomace waste, generated during winemaking. Sometimes, this waste is used to make compost or is burnt, which causes environmental contamination. The functional qualities, antioxidant capacity (AC), α-tocopherol and total phenolic compounds content (TPC) of Black Borgoña (Vitis labrusca) grape seed oil, extracted by supercritical CO2, were evaluated. The high content of linoleic acid (w-6) and monounsaturated fatty acids contributed to the beneficial effect on ​​the functional quality indices, which were 0.20, 0.23, 11.80 for IA, IT and H:H, respectively. In addition, a POV of 6.23 ± 0.08 milliequivalents of peroxide/kg oil and an anisidine index of 2.70 ± 0.05 indicated a good quality oil. Also, a high concentration of α-tocopherol (9.82 ± 0.02 mg/100 g oil) and a high TPC (114.14 ± 3.24 mg GAE/kg oil) were obtained. This study demonstrated that supercritical CO2 extraction is a suitable method for the delivery of a high-quality grape seed oil.