Survivability of lactobacilli cells upon coating with methacrylic acid copolymers

This study aimed to evaluate the coating effect of methacrylic acid copolymers (MAc) on alginate beads, with respect to protection, survivability, and in vitro release of lactobacilli cells under simulated gut conditions, and to evaluate the effect of oven drying and fluidized bed-spraying as a mean to dry and coat alginate beads with MAc. MAc-coated beads exhibited protective effects for lactobacilli cells against low acidic environment providing higher survivability (71.82–96.11%) compared to uncoated beads (28.67–61.68%), and also higher cell release under sequential gut conditions (P<0.05). Lactobacillus casei BT 1268 showed a high cell release and was thus selected for further analysis using spray coating-drying via fluidized bed. Scanning electron microscopy revealed that fluidized bed-spray drying produced beads with irregular shapes but consistent coating and with lactobacilli cells clearly embedded within the inner matrix. Oven dried and fluidized bed-spray dried MAc-coated beads of L. casei BT 1268 also showed similar cell release, indicating the possible use of fluidized bed-spray as a more economical and less time consuming method for the protection and maintenance of cell viability

Survivability of encapsulated lactobacilli in high acid foods

This study aimed to evaluate the survivability of lactobacilli cells encapsulated in calcium alginate beads coated with methacrylic acid copolymers (MAc) in high acidic foods (orange juice and mayonnaise). Lactobacilli survived well at low temperature (4 °C) for 6 wk in orange juice, 4 wk in heat-treated orange juice, 12 wk in mayonnaise, and 8 wk in heat-treated mayonnaise (P<0.05), without affecting the acidity of orange juice and mayonnaise during storage. FTIR spectra showed that the characteristic peaks of calcium alginate and MAc were not altered, designating no high affinity interaction between calcium alginate and MAc. DSC of MAc-coated alginate beads indicated an increased in melting temperature, demonstrating improvement in molecular orientation in the MAc-coated alginate beads compared to the control. Sensory evaluation revealed that panellists could detect the presence of MAc-coated alginate beads, leading to a lower acceptance score