Barley malt wort and grape must blending to produce a new kind of fermented beverage: A physicochemical composition and sensory survey of commercial products

In the last few decades, the beer industry experienced a revolutionary moment. Italy is also part of this scenario, with many microbreweries opened in the last few decades. The merging of beer and wine has led to the development of a new kind of fermented beverage, nowadays internationally known as Italian Grape Ale (IGA). The aim of this work was the physicochemical, volatile, and sensory profile characterization of 22 commercial samples. IGAs was complex and heterogeneous derived from the possibility to choose the percentage of added grape must, the process step of the addition (boiling, whirlpool, primary fermentation), different tank materials (steel, cement, wood), and different types of fermentation (bottom, top, spontaneous). However, some distinctive characteristics emerged, such as high ethanol content, low bitterness and low pH. A high percentage of added grape must can enhance these features, although it had a negative effect on foam stability. Concerning the sensory profile, maturation in wooden barrels associated with spontaneous fermentation (the “brett” character increases the vinous sensation) was the best strategy to get the flavour in between wine and beer. Taken together, these data will support the brewery to plan and make this new kind of fermented beverage.