Upcycling of grape pomace for the formulation of high added value pizza bases

In recent years, research has emphasized the reutilization of agri-food chain by-products by exploiting their functional compounds, with the aim to formulate high added value foods. Annually, the winemaking process produces significant amounts of wastes and by-products, necessitating careful management due to the large production in a limited period. Grape pomace, for example, is a source of bioactive compounds with antioxidants, anti-inflammatory and antimicrobial properties. In this context, pizza bases were formulated replacing wheat flour with 15,20 and 25% of skin flour (GS) and skin/seed flour (GM) assessing the impact of substitution on the chemical, technological and sensory properties. The highest percentage of oenological flours, allowed to label the pizza bases with “high fiber content” nutritional claim according to the EC Regulation 1924/2006 by reaching more than 6 g of dietary fiber/100 g. Moreover, in all enriched samples, and mostly when GM was used, the incorporation led to an increase in the level of anthocyanins and phenolic compounds, as well as enhanced antioxidant activity. On the other hand, as the substitution level increased, hardness, chewiness and crust and crumb color intensity were negatively affected. However, the analysis of volatile compounds, showed that the addition of these innovative flours reduced the presence of pyrazine and increased the concentration of esters, acids, ketones and aldehydes, with a consequent sensory impact, especially on the scents of must, acid and pungent.