As yeast extracts are commonly used as a source of amino acids, the present work studies the potential of one Saccharomyces cerevisiae strain and several non-Saccharomyces yeasts to be used as a source of amino acids. All the strains studied were able to grow using sugar cane molasses as medium. Pichia strains proved to be the best biomass producers, but Yarrowia showed the highest rates and the best yield of hydrolysis from protein to free amino acids. Yarrowia strains also proved to contain the greatest quantity of essential amino acids. Finally, a phylogenetic tree was obtained from the amino acid profile which agrees with the classification of the strains. (c) 2006 Elsevier Inc. All rights reserved.