Evaluating the influence of maceration practices on biogenic amine formation in wine

Biogenic amines are formed during winemaking from precursor amino acids, mainly by lactic acid bacteria during malolactic fermentation (MLF). Various factors can influence the amino acid content of the grape must and wine; including contact with the grape skins before, during and after alcoholic fermentation. The quantity and composition of amino acids in the must can potentially dictate the subsequent formation of biogenic amines. In this study we investigate the influence of compounds extracted from the grape skins by different maceration practices applied during winemaking on the formation of biogenic amines. Wines were made on small scale with two red grape cultivars. Treatments consisted of free-run juice (no skin contact), skin contact during alcoholic fermentation, cold maceration and extended maceration; followed by MLF in all treatments. Our results show that higher levels of precursor amino acids and biogenic amines were detected in the absence of skin contact, extended maceration and to a lesser extent in conventional maceration. Cold maceration before fermentation initially increased the extraction of amino acids and formation of biogenic amines, but resulted in the lowest concentrations of these harmful compounds in the final wines. Cold maceration therefore appears to have a protective effect against biogenic amine accumulation during MLF.

► Grape skin maceration can enhance amino acid extraction and biogenic amine production. ► Cold maceration led to lowest biogenic amines in finished wines. ► High biogenic amines were produced during malolactic fermentation (MLF) with conventional and extended maceration. ► No maceration also resulted in high levels of total biogenic amines after MLF. ► Pectinolytic enzyme had no impact on biogenic amine formation.