Table 4 Microencapsulation of EOS bacteria using mixed materials/blends
EOS bacterial strain | Encapsulation technique (including cross-linker and critical oxygen exposure time) | Microcapsule matrix material | Purpose of employed anaerobic conditions | Bacterial viability following Oâ‚‚ exposure | Additional notes | Reference/study |
|---|---|---|---|---|---|---|
B. bifidum CCRC 11844 | Extrusion (0.1 M CaCl2; 1 h hardening time) | Alginate + Gellan gum (supplemented with peptides and FOS as excipients) | Bacteria culturing for encapsulation | High viability during storage (4 oC, 8 weeks), SGF (1 h) and BS (1 h) exposures | Mean PS = 0.5 mm; Alginate only beads demonstrated poorer bacteria protection | |
B. lactis | Pickering emulsification (0.03% w/v tea protein; no total stirring time was mentioned) 3D printing | Tea protein + Xanthan gum | CFU plating | High viability during storage (4 °C, 11 days) in SGF (2 h), and in SIF (with BS, 2 h) | Reduced viability with hydrogels made via simple cooling-based gelation and without oil droplet incorporation; PS = 2.4 - 2.5 mm | |
B. bifidum BB01 | Extrusion (40 min hardening time) | Chitosan + Xanthan gum | Bacteria culturing for encapsulation | Moderate viability during SGF (2 h) and BS (2 h) conditions | Viability was improved with additional xanthan gum coating; PS = 450 µm; EE = 78 -92% | |
B. animalis subsp. lactis BB-12 | Emulsification (0.5 M CaCl2; 30 min gel formation/hardening time) | Alginate + Xanthan gum/Whey/Carrageenan/CNC/Milk (all containing glucose and some containing either Inulin or L-cysteine-HCl) | Bacteria culturing for encapsulation | Moderate viability during storage (4 °C and −18 °C, 30 days); Moderate viability in SGF (1.5 h) and SIF (1.5 h + 30 min pH adjustment) | All blended alginate microcapsule variations enhanced the viability protection compared to the pure alginate microcapsules; The addition of inulin improved viability, while L-cysteine-HCl only slightly increased the viability protection | |
B. bifidum F-35 | Emulsification (double layer: 10 U/g transglutaminase for WPI + 0.0655 M CaCl2 for alginate cross-linking; 3.34 h total stirring (emulsification, gelation) time) | WPI + Alginate | Bacteria culturing prior encapsulation and CFU plating | High viability during storage (in yogurt, 4 °C, 14 days) | Storage stability was not significantly higher than unencapsulated bacteria; PS ~ 280 µm | |
B. animalis Bb-12 | Emulsification (5% w/v CaCO3; 1.3–1.5 h total time of stirring) | Alginate + Chitosan | Bacteria culturing prior encapsulation and CFU plating | High viability up to 21 days, but poor by 60 days of storage in fermented dairy beverages, 4 °C; high viability in SGF (1 h) and SIF (time not reported) but poor following digestion after 60 days storage | - | |
B. infantis ATCC 15697 | Extrusion (0.4 M CaCl2; 30 min hardening time) | Alginate + WPI/PPI | Bacteria culturing prior encapsulation and CFU plating | High viability during storage (4 °C, 28 days); Moderate viability in SGF (3 h) | PS = 1.11 - 1.62 mm EE = 81.89–94.09% | |
B. animalis subsp. lactis Bb-12 | Extrusion (3% w/v CaCl2; 30 min hardening time) | Alginate + Agar | CFU plating | No storage and simulated GI studies were conducted | PS = 1.85 mm EE = 52% (39% with casein incorporation into the gel matrix) |
