Optimization of antioxidant extraction and characterization of oil obtained by pressing cold from Vitis labrusca seeds

The grape industry generates a large number of residues as peel, seeds and pulp, which also contain antioxidants (Santos et al., 2011). This has aroused the interest of the industry itself in recycling, in order to reduce costs, environmental impacts, and add value to the product (Spigno & De Faveri, 2007). Seeds of vinification were the residues that started the exploitation of the phenolic compounds of this class, followed by bagasse (Melo, 2010). By this way, considering the diversity of polyphenols sources from plant matrices and their physicochemical structures, as well as its properties (such as antioxidant activity), it is hard to find a universal extraction method that can be applied in all samples (Alara et al., 2018). Aspects such as time, temperature, particle size and type of extraction are crucial because they alter the yield of the extracted antioxidant compounds (Alcântara et al., 2019). In addition, the extractor solvent polarity also affects the antioxidants extracted (Bosso et al., 2016). In this regard, the extraction optimization for each sample plays a key role because it also enhances the global economic process (Mukherjee et al., 2014). In this manner, the development of grape seeds extraction method can add commercial and industrial values for grape culture. By this way, this study seeks to optimize the extraction process by statistical simplex-centroid mixing scheme, assessing the obtained extracts, as well as, the oil extracted from seeds by cold pressing in terms of antioxidant activity, resveratrol content and fatty acids.