Electrosprayed Ethyl Cellulose Core-Shell Microcapsules for the Encapsulation of Probiotics

Area of Science:

• Materials Science
• Biotechnology
• Food Science

Background:

• Probiotic viability is crucial for their health benefits.
• Traditional encapsulation methods can be limited by shell material properties and processing solvents.
• Ethyl cellulose (ETC) offers potential as a protective shell material.

Purpose of the Study:

• To develop electrosprayed ethyl cellulose core-shell microcapsules for probiotic encapsulation.
• To evaluate the effect of different core compounds on probiotic stability.
• To assess the protective efficacy of ETC microcapsules against environmental stressors.

Main Methods:

• Production of ETC core-shell microcapsules via electrospray.
• Encapsulation of Bifidobacterium animalis subsp. lactis (Bifido) with varying core compositions (concentrated Bifido, Bifido-maltodextrin, Bifido-glycerol).
• Characterization of microcapsule size, water activity, and viable cell counts.
• Assessment of probiotic stability over four weeks at 30 °C and 40% RH.

Main Results:

• Core-shell microcapsules ranged from 3 µm to 15 µm in diameter.
• Microcapsules exhibited low water activity (<0.20) and high initial viable cell counts (10^9-10^11 CFU/g).
• Bifido-glycerol core samples showed minimal viable cell loss (≤3 log CFU/g) after four weeks, compared to non-encapsulated Bifido (7.57 log CFU/g loss).

Conclusions:

• Electrosprayed ETC core-shell microcapsules provide a protective matrix for Bifido probiotics.
• Glycerol as a core compound significantly enhances probiotic cell viability and stability.
• This encapsulation technique extends probiotic viability, overcoming limitations of solvent-based shell materials.