Wine Expert #8 – the many roles of Nitrogen during alcoholic fermentation
Wine yeast requires certain essential elements to transform must into wine: sugars, vitamins and minerals, some oxygen, and also very importantly, a sufficient concentration of Yeast Asssimilable Nitrogen. This type of nitrogen (YAN) is composed of amino acids, some small peptides and ammonium that can be used by yeast cells to not only complete fermentation, but also to fully develop the sensory profile of the wine. Many wine musts are deficient in nitrogen and the type of nutrient used and the timing of additi on is crucial in the development of AF.