Optimizing some conditions for spray drying in synbiotic capsule from Bacillus subtilis natto strain

The study is of determination of various conditions for spray drying in producing synbiotic in the form of capsule from Bacillus subtilis natto. The experiments were conducted to examine effects of various factors such as the resistant starch-to-matodextrin ratio before drying, the inlet gas temperature and the inlet flow. The optimization experiments are administered: a ratio of wall materials to the core material is 5% (w/v) in which the ratio of resistant starch and maltodextrin is 1:9, the inlet gas temperatureis 110 0 C, the inlet flow is 5.60 ml/minute and the spray pressure is 2 bar. In the condition for spray drying as mentioned earlier, the initial step for trial production of synbiotic capsules was conducted with the cell density of B.subtilis natto being 8.55 ± 0.18 log(CFU/g), the activating effect of nattokinase is 518.2 FU/g and the moisture is 9.11%. During 60 days’ preservation of the product, the resulting indexes such as the cell density of B.subtilis natto in the capsule, the activating effect of nattokinase and the moisture are stable.