World wine industry transforms 10% -25% of raw grapes into residues, mainly represented by lees, grape marcs, seeds and stems. These byproducts are a rich source of polyphenols and therefore they can be used to produce new added value products. The aim of this work was to determine the best process conditions (treatment time, % of ethanol and pH of the solvent) during solid-liquid extraction of polyphenols from grape marcs, by analyzing the phenolic content of the extracts, namely: total polyphenol content, flavanols, flavonols, phenolic acids and anthocyanins. Antioxidant activity of the extracts was also determined. An extraction time of two hours was enough since longer times did not increase process yields. Best extraction yields were obtained for 75% ethanol solutions. Basic pH led to better yields in extracting media with low percentage of ethanol, whereas acid pH presented better extraction yields in extracting media with high percentage of ethanol. Among all the polyphenols extracted, anthocyanins were the most abundant representing over 40% of the total. In general, the best process conditions were 2 h of extraction in a 75% EtOH liquid mixture at pH = 2.

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The relevance of plant-based food alternatives to dairy products, such as vegetable milks, has been growing in recent decades, and the development of systems capable of classifying and predicting the sensorial profile of such products is interesting. In this context, a methodology to perform the sensorial analysis of vegetable milks (oat, soya, rice, almond and tiger nut), based on 12 parameters, was validated. An electronic tongue based on the combination of eight metals with pulse voltammetry was also tested. The current intensity profiles are characteristic for each non-dairy milk type. Data were processed with qualitative (PCA, dendrogram) and quantitative (PLS) tools. The PCA statistical analysis showed that when using three first principal components, which covered 77% of variance, the eight samples can be differentiated, and the preparation method (artisanal milks or commercial) is one of the main differentiation factors, together with raw material type. The

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