Production of probiotic Lactobacillus acidophilus cell cncentrates using solid state Fermentation technology and their performance

To overcome many problems associated with liquid culture techniques for the production of cell concentrates, SSF used after maintaining the following conditions technique, such as paddy husk, fortified with the various additives attempted to produce cell concentrates of Lactobacillus acidophilus 111. Factors affecting the growth of L. acidophilus 111 in respect of nutrients, minerals, salts, legumes, surfactants, pH, temperature, moisture content, static or shaking method of incubation, CO₂ atmosphere were studied. The results showed that a viable count of 10 log ₁₀ cfu/g could be achieved when peptone (1%), yeast extract (1%), skim milk powder (1%), MnSO₄ (0.05%), black gram (10%), tween 40 (1%) were used with the growth conditions of pH of 7.0, incubation temperature of 37°C, moisture content of 50%, CO₂ flushing. To enhance the keeping quality, the SSF culture was dried at 15, 20, 25 and 30°C atmospheric temperatures for 20 h. The results showed that the viable count was only marginally reduced to 8 log₁₀ cfu/g on drying at 20°C for 20 h. The dried SSF culture when used as an inoculum, performed equally with the liquid culture in milk with respect to the curdling time and titratable acidity.