Sedimentation clarification of viura musts. Utilization of amino acids during fermentation

The influence of sedimentation on viura mustʹs concentration of free amino acids and changes during fermentation were studied; the results were compared with an unclarified sample. The protein fraction was reduced by this treatment; the amino nitrogen increased slightly in the decanted must, and the concentration of ammonium nitrogen was similar in both samples. The decanted must had a greater concentration for most of the amino acid constituents of proteins, neutral as well as basic. This treatment did not alter the medium sufficiently to modify yeast utilization of these nutrients during fermentation; in fact, in both samples, basic, neutral, and acidic amino acids were consumed in a similar manner in the first half of fermentation (until 50% sugar consumption) and were excreted similarly in the freshly produced wine.