Influence of Oxygen on Proline Utilization During the Wine Fermentation

Abstract

In order to overcome sluggish or stuck fermentations, it may be necessary to utilize oxygen and yeast-utilizable nitrogen sources found in some yeast foods. Government regulations in the US preclude the use of large amounts of yeast foods — even those derived from yeast or proteins often employed as food ingredients. The present work describes the conditions under which proline, an amino acid naturally present in high concentrations in musts, can be utilized fully as a source of nitrogen. Oxygen is required for proline degradation; it is also a requirement to ensure sufficient yeast growth and to avoid sluggish fermentations.