Lesaffre Et Cie

Societe Industrielle Lesaffre

Philippe Clement

Jean-Paul Rossi

Annie Loiez Nee Hennette

Didier Colavizza

Annie Loiez Born Hennette

New broad spectrum strains of bread-making yeast having

Strains of bread-making yeast, a process for obtaining same, and the

A complete and reproducible process for producing novel strains of yeast, comprises making a first screening test and at least one other screening test selected from a group of screening tests which do not resort to any measurement of gas release, selecting by means of said first and at least one other said screening test the desired strains from a group of diploid strains prepared previously either by hybridation, or by mutation of existing strains. The tests are as follows: A first test consists of measuring the average multiplication coefficient of a given strain by following the optical density variation of a standard medium seeded by a suspension of cells obtained from this strain. A second test consists of measuring in the same manner the average multiplication coefficient of the said strain in the presence of an inhibitor acid added to the standard medium. A third test consists of measuring the maltose adaptation of said strain in the presence of glucose by determining the amount of maltose subsisting in a standard medium after a known amount of glucose added to this medium has been completely consumed. A fourth test consists of measuring the invertase content of said strain. A fifth test consists of measuring the latent time of said strain. The hybridation can consist of systematic haploid crossings derived from quick Saccharomyces Cerevisiae strains adapted to maltose and haploids derived from very slow strains not adapted to maltose, but well adapted to sweet doughs and sometimes also to acid doughs.

Strains of yeast for bread-making and novel strains of yeast thus

Active dried baker's yeast is prepared by selecting a yeast strain stable to drying, cultivating the yeast strain in several aerobic fermentation stages and selecting conditions for the last stage that produce a compressed yeast having preferred gas release characteristics, harvesting and carefully washing the yeast from the last stage to obtain compressed yeast having the preferred gas release characteristics, adding to the compressed yeast an emulsion of an emulsifying agent, dividing the resultant mixture into fine particles, and drying the particles by flash pneumatic conveyor drying and/or fluidized bed drying to obtain active dry yeast having greater than 92% dry matter content. The dry yeast have an activity almost equal to fresh yeast on non-sweetened dough or on sweetened dough.

Preparation of dried baker's yeast

Fermentation of acid-containing dough in bread-making is carried out with a baker's yeast in the form of compressed fresh yeast or dried yeast that has reduced inhibition to acid in the dough. The yeast is preferably prepared by selecting a strain of quick yeast, adapted to maltose and stable on conversation and drying, and cultivating the yeast by a process wherein during a last discontinuous cycle of multiplication of the yeast, a discontinuous flow of molasses is carried out by brief interruptions of flow.

Fermentation of acid-containing doughs

A dry yeast composition in particulate form containing at least 92% dry matter is prepared consisting essentially of active dry bakers' yeast capable of fermenting sweetened doughs containing more than 5% sugar and an emulsifying agent having an HLB value of between 3 and 11. The emulsifying agent is added to the yeast before drying and protects the yeast during drying.

Growing community of inventors

Roubaix, France

Philippe Clement