August 14, 2007/Tokyo/Asia Pulse -- Japan's Kirin Holdings Co. and the Keio University Institute of Advanced Biosciences have discovered a strain of brewer's yeast that processes large amounts of sulfurous acid -- an antioxidant that helps keep beer fresh - without synthesizing hydrogen sulfide, which has an unpleasant sulfur smell.

The yeast was discovered by conducting a thorough analysis of the metabolic products synthesized by brewer's yeast. The study revealed that brewer's yeast strains synthesize large amounts of hydrogen sulfide when processing a tiny number of metabolites of the amino acid asparagine.

Using this information, the research group selected yeast with large amounts of asparagine metabolites. The result was a brewer's yeast that synthesizes around 150% more sulfurous acid without yielding any hydrogen sulfide. Kirin will use this yeast to brew its beers.

The company has developed a proprietary method for this kind of metabolome analysis and plans to adopt the same technique for producing other alcoholic beverages, medicines, health foods and functional foods.

From the August 27, 2007, Prepared Foods e-Flash