Grape seed pomace as a valuable source of antioxidant fibers

Abstract

BACKGROUND Grape seed pomace is a valuable by‐product from winery/oil extraction industries and a potential source of bioactive compounds. Hot water extraction is the most widely used technology for polysaccharide recovery from plant and seed sources. To obtain an antioxidant fiber‐rich extract (AFE) from defatted grape seed pomace, seed:water ratio (1:10–1:20) and extraction temperature (70–90 °C) effects on extraction yield, total sugars, total phenolic compounds and condensed tannins were investigated. RESULTS The best extraction results were achieved at the highest seed:water ratio and temperature. At these conditions, the extraction yield and total sugar content of the freeze‐dried AFE were 100.1 g kg−1 and 725.3 g kg−1, respectively. The AFE presented high total phenolic content (16.2 g GAE kg−1), condensed tannins (515.1 mg CAT kg−1), soluble (219.1 g kg−1) and insoluble fibers (132.4 g kg−1), besides protein (171.1 g kg−1) and ash (152.6 g kg−1). The antioxidant capacity of the AFE was 382.7, 823.7 and 1439.4 μmol Trolox g−1 for DPPH, ABTS and ORAC methods. CONCLUSION The AFE was shown to be not only an interesting source of fiber with antioxidant capacity, which could become a potential foodstuff, but also an ecofriendly and sustainable alternative to use grape seed pomace. © 2019 Society of Chemical Industry

ACE Inhibitory and Antihypertensive Activities of Wine Lees and Relationship among Bioactivity and Phenolic Profile

“…These compounds are highly valued by the food, pharmaceutical, and cosmetic industries because they show a wide range of beneficial health effects. In this sense, winery by-products have been successfully used to obtain antioxidant [31], antimicrobial [32], anti-inflammatory [33], antihyperglycemic [34], or antihypertensive compounds [14,16,17,35]. For instance, extracts rich in phenolic compounds (proanthocyanidins or resveratrol), with antihypertensive properties in both rats and humans, have been extracted from stem, grape seeds, or skin, respectively [13,[15][16][17][36][37][38].…”

Biologically active compounds contained in grape pomace

“…Similarly to the determination of the total amount of polyphenols, it was not possible to apply the ANOVA test. Therefore, a comparison of the obtained data was performed using the Kruskal-Walllis test as displayed in (2019) publishing the values ranging from 0.12 ±0.0 to 0.23 ±0.0 mmol Trolox.g -1 dry weight.…”

“…Namely, it was for example herbs, vegetables, fruits, or agro-industrial waste. The reason for attention on these products is because they are rich in polyphenols and they can be used instead of synthetic antioxidants that are used in the pharmaceutical, food, or cosmetic industry (Casagrande et al, 2019).…”

Optimization of extraction time and temperature for natural antioxidants of öküzgözü grape pomace using various solvent ratios

“…Although, the highest antocyanin concentration was found at 40 °C for 90 min, a slight decrement of antocyanin content at 40 °C for 150 and 180 min was observed because of the degradation of anthocyanin during application and the formation of new compouds. In addition, the chemical components and anthocyanin values of winery waste products vary according to the type of grape, growing conditions, extraction parameters and analysis method (Ben Aziz et al, 2019;Costa et al, 2019).…”