Improvement of fermentative yeasts <i>S. cerevisiae</i> by Non-GMO strategies for the reduction of urethanes in Sherry wines

During alcoholic fermentation, the yeasts responsible for process produce various metabolites, including urea. The reaction of urea with ethanol spontaneously generates ethyl carbamate in wine, a carcinogenic metabolite whose concentration needs to be regulated. Yeasts during arginine metabolic pathway. For this purpose, adaptive evolution has been used by using toxic analogue l-arginine, l-canavanine, selective pressure, once increasing genetic variability population sporulation and subsequent conjugation. Using strategy, five putative variants parental yeast have obtained seem reduced production, thus being able achieve lower carbamate.