Aureobasidium pullulans (de Bary) Arnaud (Ach 1-1) was grown in a glucose fed-batch fermentor to 106 g dry wt l -1 in 48 h. The cells were dried in a fluidized bed dryer with a final viability of 62%. After 7 months at 4°C, the viability was 28% of the initial value (= 2.3 · 10 10 c.f.u. g -1 dry matter). A protection level of 89% was achieved with the biomass preparation at 1 · 10 8 c.f.u. ml -1 after 28 and 7 days for apples stored respectively at 5 and 25°C against Penicillium expansum. Our process is suitable to produce large quantities of the strain Ach 1-1 as biological control agent for apple preservation.

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Bifidobacterium crudilactis FR62/b/3 belongs to a new population of bifidobacteria isolated from raw milk and raw milk cheese. The objective of this work was to study the large scale culture of the strain and its stability in a dry formulation. Growth rate of Bifidobacterium crudilactis FR62/b/3 was optimal at a pH of 5.0 and a temperature of 37˚C. At a temperature growth of 33˚C and a pH of 5.0, the stationary phase was reached after 22 h, the viable cell number and the mean dry biomass concentration were respectively of 8.3 × 10 9 CFU/mL and of 2.1 g/L. Resistance of Bifidobacterium crudilactis FR62/b/3 to freeze-drying and effect of a variety of cryoprotectants to maintain the viability were also evaluated. Sorbitol was the most suitable cryoprotectant for freeze-drying as well as storage whereas sucrose and monosodium glutamate were only efficient during storage.

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