Process Development for the Spray-Drying of Probiotic Bacteria and Evaluation of the Product Quality

In our laboratory, we do research on beneficial microbes, including probiotics, which are live microorganisms that can be added to food to improve the health of consumers, Usually by competing with pathogenic bacteria in the gut to exclude them and relieve symptoms, like diarrhea or other gastrointestinal disorders. Nowadays, many techniques have been applied to guarantee that the probiotics will survive in food during the shelf life. And also, they needed to tolerate the harsh conditions of the gastrointestinal tract to exert their beneficial effects inside the gut.

We studied many technologies that can enhance the survival of probiotics, either in food or in the human host. Among the techniques, microencapsulation by spray drying is of great interest because it's simple, fast, and reproducible, providing high yields at low energy requirements. It's challenging, however, to determine the right conditions to obtain dried probiotics.

And for that, suitable protectants must be chosen. Skim milk, maltodextrin, or other like probiotic inulin have been used with different probiotic strains. The area of microencapsulation is a happily evolving field of research that has the potential to impact the food industry by providing new products to be used as functional ingredients.

In this study, we demonstrate how to obtain a microencapsulated preparation of a potential probiotic culture using the spray drying technique. We also show how to determine the main parameters to characterize the powder, obtain it, and how to evaluate the survival rate of the probiotic.