Overproduction of 2-phenylethanol by industrial yeasts to improve organoleptic properties of bakersʹ products

2-Phenylethanol (PEA), an important alcohol derived from phenylalanine, is involved in aroma and flavour of bakersʹ products. Four spontaneous mutants of an industrial bakersʹ yeast, V1 strain, were isolated for their resistance to p-fluoro-DL-phenylalanine (PFP), a toxic analogue of L-phenylalanine. Mutants overproduced this amino acid and showed variations in their internal pool for several other amino acids. Moreover, a rise in PEA production after growth in industrial medium (MAB) was observed in three of the mutants, although their growth and fermentative capacities were slightly impaired. However, concentration of PEA remained higher during dough fermentation and also after baking, thus improving taste and aroma in bread.