Study of some volatile compounds of raw grappa obtained using marc treated in different ways and stored in plastic tunnels
Marc stored in plastic tunnels was treated as follows: without any treatment; with the addition of lysozyme; with the addition of potassium metabisuphite solution in water; and with the addition of potassium metabisulphite powder, selected yeast, sugar and N-compounds. After a storage period of 80 d, marc was distilled in batches. The raw grappa made with treated marc resulted in lower levels of fusel alcohols and higher concentration of ethyl esters from C8 to C12 compared with grappa made with untreated marc. Sensory evaluation indicated that the marc treated with selected yeast was preferred.