Spray drying of probiotics and other food-grade bacteria: A review

Background: Probiotic and starter bacteria are generally dried to produce easy-to-use ingredients that are stable and flexible for applications in the food, feed and pharmaceutical industry. The overall demand for dried probiotic bacteria has increased in the context of a rapidly growing market, evidencing the need for their larger scale production. Scope and approach: The spray-drying of bacteria enables a larger production scale than the freeze-drying currently used; energy costs are lower and the process is sustainable. This is also a promising way to microencapsulate bacteria within various protective matrices to ensure their improved resistance during storage, technological processes and digestive stresses. Key findings and conclusions: This review highlights some key strategies to improve the viability and efficacy of probiotics spray-drying, such as the enhancement of bacterial resistance, improved protection of the drying medium and optimization of the drying process. It also focuses on factors during the pre- and post-drying stages which may influence the quality and efficacy of spray-dried probiotic powders. (C) 2017 Elsevier Ltd. All rights reserved.