The present invention relates to a dry grape extract that is characterized in that it comprises one or more polyphenol compounds in a weight percentage of the total of the composition of the extract of between 5% and 70%, both limits included, said percentage relating to the total content of polyphenols present in the extract, and said polyphenol or polyphenols preferably being selected from flavan-3-ols, myricetin, quercetin, ellagic acid, and any combination thereof, which, when mixed in different concentrations, form specific compositions of the extract with functional properties and high oxidant potential. Said extract is achieved by means of drying a liquid composition extracted directly from grapes or indirectly from vinification-process by-products. Said extract can be used as it stands as a nutritional supplement, or as a functional ingredient in a supplement or in a food. In addition to the food use thereof, the extract may be used to produce cosmetic products.
