Emerging Technologies and Coating Materials for Improved Probiotication in Food Products: a Review

Abstract

From the past few decades, consumers’ demand for probiotic-based functional and healthy food products is rising exponentially. Encapsulation is an emerging field to protect probiotics from unfavorable conditions and to deliver probiotics at the target place while maintaining the controlled release in the colon. Probiotics have been encapsulated for decades using different encapsulation methods to maintain their viability during processing, storage, and digestion and to give health benefits. This review focuses on novel microencapsulation techniques of probiotic bacteria including vacuum drying, microwave drying, spray freeze drying, fluidized bed drying, impinging aerosol technology, hybridization system, ultrasonication with their recent advancement, and characteristics of the commonly used polymers have been briefly discussed. Other than novel techniques, characterization of microcapsules along with their mechanism of release and stability have shown great interest recently in developing novel functional food products with synergetic effects, especially in COVID-19 outbreak. A thorough discussion of novel processing technologies and applications in food products with the incorporation of recent research works is the novelty and highlight of this review paper.

Probiotic Properties Including the Antioxidant and Hypoglycemic Ability of Lactic Acid Bacteria from Fermented Grains of Chinese Baijiu

“…Adequate bacterial activity during gastrointestinal transport is a prerequisite for the health benefits of probiotics entering the human body [ 36 ]. Tolerance to gastrointestinal conditions (low pH, digestive enzymes, bile salts) is essential for probiotic activity [ 23 , 37 ].…”

Natural sources and encapsulating materials for probiotics delivery systems: Recent applications and challenges in functional food development

“…However, the physical isolation of microbial cells during encapsulation shields the cells from direct exposure to high oxygen levels permeating the formulation. Enhanced oxygen tolerance in encapsulated probiotics has been demonstrated in several investigations, notably, in the dairy industry for products such as yogurt, ice-cream, cheese etc ( 24 , 75 ). Alginate encapsulated L. acidophilus and Bifidobacterium spp.…”

“…Another disadvantage of freeze drying is the necessity to select probiotic bacteria tolerant for low process temperatures. Researchers recommend a pre-stress conditioning phase, exposing bacteria to low temperatures to acclimate them as well as optimizing the process conditions to ensure viability of the cells ( 24 ).…”

“…Nature of encapsulating material has a crucial role in determining encapsulation efficiency. A number of polymeric materials including polysaccharide hydrocolloids (alginate, xanthum, chitosan, carrageenan, cellulose), fats and proteins have been used for microencapsulation ( 24 ). Alginate is one of the most widely used materials due to its characteristics property to resist pH 2–2.5 (gastric pH) and expand at neutral to alkaline pH ( 38 ) ( Table 2 ).…”

“…An alternative strategy to enhance the oxygen tolerance of encapsulated cells can be to co-encapsulate an oxygen-consuming bacterial strain such as Streptococcus thermophilus , and create a favorable microenvironment for microaerophilic/anaerobic bacterial survival ( 24 , 78 ). Additional precautions can be taken by setting up anaerobic environment during the encapsulation process, deoxygenating the encapsulating matrix in liquid phase ( 79 ) and adding anti-oxidants such as L-cysteine to sustain the microaerophilic and anaerobic organisms ( 77 ).…”