Development, characterization and viability study of probiotic microcapsules produced by complex coacervation followed by freeze-drying

Abstract

Technique of complex coacervation was used to produce microcapsules of Lactobacillus acidophilus La-5 encapsulated in gelatin and gum arabic which were then freeze-drying. Microcapsules were characterized using scanning electron and optical microscopy, and resistance of probiotics was evaluated during release into a simulated gastrointestinal tract and storage at different temperatures. The complex coacervation process produced microcapsules with a high encapsulation efficiency (77.60% and 87.53%), ranging from 127.14-227.05 μm with uniform distribution. Microencapsulation was an efficient approach to achieve significant protection of probiotics against simulated gastrointestinal conditions compared with free cells. Encapsulation also improved the viability of probiotics during storage at either −18 ºC for 120 days, 7 ºC for 105 days or 25 ºC for 45 days. Therefore, complex coacervation was demonstrated to be adequate and promising for encapsulation of probiotics.

Effect of two types of wall matrix on viability of lactobacillus plantarum under simulated gastrointestinal fluids

“…Indeed, a low gastric pH (pH 2.0) and the presence of the digestive enzyme pepsin weakens Lactobacillus paracasei and reduces its survival [41,1]. Low pH damages cell membranes, changes the structure of proteins and nucleic acids and thus disrupts biochemical pathways [53]. Our nding was similar to the study performed by Ebrahimnezhad et al [15].…”

A Brief Review of Edible Coating Materials for the Microencapsulation of Probiotics

“…Successful methods used in the microencapsulation of probiotics include: spray drying [21,22]; spray chilling (also called spray cooling or congealing) [23,24]; spray freeze drying [25,26]; lyophilisation [27,28]; electrospraying [29,30]; layer-by-layer [31,32]; fluidised bed drying [33,34]; extrusion [35,36] and its improved version: the vibrating nozzle technology [37,38]. Emulsification [39,40] and coacervation [41,42] are other important and often used physicochemical techniques. Although uniform particle size distribution may be preferred in many applications, these different microencapsulation methods produce microcapsules with a wide range of particle sizes.…”

“…The fact that gelatine is one of the oldest and multiple-purposes ingredients in the food industry makes it also one of the most studied proteins as coating agent in the preparation of microcapsules [152]. Moreover, the properties of gelatine and its ability to interact with a wide variety of polysaccharides allows its use as a coating material in a several microencapsulation methods, such as extrusion, complex coacervation, spray chilling, spray drying, and lyophilisation [23,42,67,100,153,154]. Another particular advantage of using gelatine as a coating material is its linear structure, which provides a better oxygen barrier than globular proteins.…”

Examining the Effect of Freezing Temperatures on the Survival Rate of Micro-Encapsulated Probiotic Lactobacillus acidophilus LA5 Using the Flash Freeze-Drying (FFD) Strategy

“…The typical freeze-drying process consists of 3 steps: freezing, primary drying, and secondary drying. During these 3 steps, cells are exposed to various stresses, especially dehydration, compromising cell survival [ 28 ]. During FD the following process occurs: freezing at low temperatures below the melting point, drying by sublimation at a pressure below that corresponding to the triple point and desorption of the bound water [ 29 ].…”