Encapsulation of probiotics in soybean protein-based microparticles preserves viable cell concentration in foods all along the production and storage processes

Abstract

The influence on the stability of Lactobacillus plantarum CECT 220 (25 °C/60% relative humidity) of microencapsulation by simple coacervation followed by spray-drying using different Ca²⁺-to-soybean protein isolate ratios was evaluated. After optimisation, the selected soybean protein concentrate (SPC) microparticles were used to evaluate the tolerance of L. plantarum under acidic conditions (lactic acid, pH = 4; and HCl, pH = 3) and heat stress (80 °C for 1 min) in contrast to free cells. Moreover, after the heat treatment, the influence of the simulated gastric fluid was evaluated. Additionally, different foods were formulated using either microencapsulated or freeze-dried L. plantarum, and the stability of cells during the shelf-life of the formulated foods was studied. Results show that encapsulation with SPC enhanced significantly the stability of the Lactic Acid Bacteria all along the probiotic food value chain, from production to the end of the food shelf-life.

Keywords:

• Soybean proteins
• probiotics
• encapsulation
• thermal resistance
• gastric resistance
• probiotic food value chain

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Fundación Obra Social La Caixa (Proyecto “Desarrollo de tecnologías para la incorporación eficiente de probióticos en alimentos – BIPRO”).