Acetaldehyde Vapors Influence Postharvest Quality of Table Grapes

Abstract ‘Sultanina’ and ‘Perlette’ grapes ( Vitis vinifera L.), with initially low sugar concentrations (13% to 14% total soluble solids content; TSS) and high acidity received postharvest application of 0.2% to 0.9% acetaldehyde vapors for 24 hr. This treatment increased TSS, decreased acidity of the juice, and enhanced the sensory preference by judges in a test panel. However, the response was limited to early picked fruit with low TSS and high acidity and the treatment damaged the berries of ‘Sultanina’ grapes and left some off-flavor. The levels of acetaldehyde and ethanol in the juice were positively correlated with the amount of applied acetaldehyde, the level of ethanol being 20 times higher than that of acetaldehyde. After 4 days of shelf life, the levels of both acetaldehyde and ethanol declined in the juice.