Baker's Yeast

Animalia sp.; Apis mellifera; Candida krusei; Plantae sp.; Saccharomyces diastaticus.

British Isles; Cuba; Dominican Republic; Egypt; former USSR; Georgia; Ireland; Netherlands; Puerto Rico; UK.

Colonies. Growth in 5% malt extract: after 3 days at 25°C, the cells are globose, ovoidal or elongate, (3.0-8.0) × (5.0-10.0) μm, and are usually isolated or in small groups. After one month at 20°C, a sediment is present. Growth on 5% malt agar: after one month at 20°C, growth is butyrous and light cream-coloured. The surface is smooth, usually flat, occasionally raised or folded and opaque. Growth on the surface of assimilation media: pellicles are not formed. Dalmau plate culture on morphology agar: pseudohyphae are either not formed or are rudimentary. Teleomorph. Formation of ascospores: vegetative cells are transformed directly into persistent asci containing one to four globose to short ellipsoidal ascospores. Ascospore formation, observed almost exclusively on acetate agar, was usually below 10% except in highly fertile homothallic strains where sporulation ranged from 40-95% in 6-10 days at 20°C.