Effect of the drying methods on the stabilization of symbiotic microbeads produced by ionic gelation

Lactobacillus salivarius was encapsulated by ionic gelation using high polymerization degree agave fructans and sodium alginate to obtain symbiotic microspheres stabilized by different drying methods. The microbeads were characterized by physicochemical, reconstitution, microstructure, thermal, radiographic and infrared properties. The viability of L. salivarius was evaluated for one month at 4 °C and under in vitro gastrointestinal conditions. The ionic gelation-drying technique allowed an encapsulation efficiency greater than 90 %. Oven-dried microbeads showed higher viability under in vitro gastrointestinal conditions. Freeze-drying microbeads showed higher viability during storage at 4 °C, and spray-dried microbeads showed a more notable survival at 40 °C after one month of storage. All samples showed up to 7 log CFU/g of viability after in vitro digestion, which is a benefit for consumer health. It was concluded that the ionic gelation-drying process allows obtaining dry microbeads with the potential to be added to various food products.