Microencapsulation of Lactobacillus plantarum ATCC 8014 through spray drying and using dairy whey as wall materials

- Lactobacillus plantarum ATCC 8014 was microencapsulated with dairy by-products.
- Viable cell counts in all microcapsules after drying were above 9.0 log CFU g−1.
- The microcapsule cell count was above 7.0 log CFU g−1 after drying and milk storage.
- Whey and whey retentate provided high resistance in a simulated gastrointestinal tract.

The present work proposes the use of whey, permeate and whey retentate as wall materials for the microencapsulation of Lactobacillus plantarum ATCC 8014 by spray drying and reveals that whey and whey retentate are the best wall materials for protecting bacterial cells from high temperatures during spray drying. After 56 days of storage at 20 °C, all microencapsulated samples showed viable cell counts above 6 log colony-forming units (CFU) g−1, the minimum quantity of probiotic bacteria required for functional food. The microcapsules in milk stored at 4 °C for 42 days also showed cell counts above the minimum value for functional foods. The microcapsules were exposed to conditions simulating the gastrointestinal tract, and cell counts were above 8 log CFU g−1. In these conditions, whey and whey retentate showed the best survivability, and the permeate in the presence of 0.5% (w/v) bile salts did not provide protection. Microcapsules produced using the various types of dairy whey showed no differences in morphology and measured 7.0 ± 1.0 μm in size. Whey, permeate and whey retentate are promising and suitable wall materials for the process of microencapsulation through spray drying of probiotic microorganisms.