Bread making with Saccharomyces cerevisiae CEN.PK113‐5D expressing lipase A from Bacillus subtilis: leavening characterisation and aroma enhancement

Summary Lipase A from Bacillus subtilis was expressed in the yeast Saccharomyces cerevisiae CEN . PK 113‐5D strain as a cell wall‐immobilised enzyme. The recombinant yeast was used in bread making to test the effect of lipase A on the bread properties such as rheological and aromatic properties. The results were compared to the not transformed strain and the commercial baker's yeast. The recombinant strain resulted a good leavening agent comparable to the commercial baker's yeasts provided 1% sucrose was added to the dough. Whereas, during the leavening, the trend of the rheological properties (cohesivness, gumminess and rigidity) differed from the commercial and the nontransformed (NT) strains. Moreover, using of the recombinant strain enhanced total aroma which achieved in the baked product a value of 9 μg per g product vs the 4 and 5 μg per g product of the NT strain and the commercial baker's yeast, respectively. To our knowledge, this is the first time that a bacterial lipase is used in bread making.