Lactobacillus plantarum 21805 encapsulated by whey protein isolate and dextran conjugate for enhanced viability

Probiotics incorporated into food products are often insufficiently potent because of unfavorable interference during processing. This study addressed these issues by encapsulating Lactobacillus plantarum into whey protein isolate (WPI) and dextran (DX) conjugates using an encapsulator. The objective of this work is to investigate the effect of encapsulation using WPI and DX conjugates on the viability of Lactobacillus plantarum. The formation of the conjugates was confirmed with absorbance of the intermediate- and late-stage products, degree of grafting, browning index, and gel electrophoresis. Extending the heating time from 1 to 5 h increased the content of high molecular weight conjugates. These conjugates provided better protection of probiotics under processing stress conditions, gastrointestinal conditions, and storage. Furthermore, encapsulated L. plantarum exhibited a reduction of only 0.33 log CFU/mL after 90 d of storage at 4 °C. Thus, microencapsulation of probiotics can enhance the viability of functional food products and facilitate corresponding research.