Clinical trials have demonstrated that an increase in the number of probiotic bacteria in the gut promotes gut health and resistance to disease (Audet et al., 1988). However, many studies have shown that the amount of probiotics that reach the sites where it can provide benefits is often very low (Chandramouli et al., 2004). Factors that cause a significant decrease in probiotic numbers include: low pH, presence of oxygen in the product, storage temperature, etc. and extreme conditions of the digestive system (Charles and Ruth, 1998; Chandramouli et al., 2004; Dimantov et al., 2004). The microencapsulation technique was developed to enhance the survival of probiotics under adverse conditions (Dimantov et al., 2004; Fabian and Elmadfa, 2006). Commonly used microencapsulation techniques in probiotic microencapsulation include extrusion, emulsification, and spray drying (Chandramouli et al., 2004; Dimantov et al., 2004). The extrusion compression technique is the simplest method of making microencapsulated products (Dimantov et al., 2004). However, the large size of the composition obtained by this technique affects the sensory properties of the product (Chandramouli et al., 2004). Emulsification technique for smaller composition size and application potential in large production. With this method, the size of the composition is still large, affecting the organoleptic properties (Dimantov et al., 2004). In addition, microencapsulation products from emulsification technique are more expensive than extrusion techniques due to the oil consumption in the preparation process (Gill et al., 2001). Spray drying technique has advantages for small-sized inoculants, does not affect the organoleptic, economic efficiency and can be applied on a large scale (Chandramouli et al., 2004, Dimantov et al., 2004). However, the weakness of the spray drying technique is its low survival rate and instability during storage, as well as its ineffectiveness in protecting probiotics under artificial gastric conditions (Jankowski et al., 1997). ). Research by Ding et al. (2009) showed that the microencapsulation carrier plays an important role in protecting probiotic bacteria during storage, under bile salt and gastric conditions. Therefore, carrier selection is essential to preserve probiotic activity. Maltodextrin is a starch hydrolysis product with prebiotic properties and is commonly used in spray drying as a carrier with its anti-adhesion properties during drying (Kailasapathy, 2002). Whereas whey protein is an industrial by-product, probiotic microencapsulation by this carrier has significantly enhanced probiotic efficacy in previous studies (King, 1995; Charles and Ruth, 1998; Adhikari et al. al., 2000; Krasaekoopt et al., 2003). Therefore, the combination of these two carriers will improve the viability of the probiotic during spray drying as well as under storage conditions. Prebiotics are short-chain carbohydrates that cannot be broken down by human enzymes but are a source of substrates for probiotic bacteria to reach the colon (Chandramouli et al., 2004). Therefore, products that are fortified with both probiotics and prebiotics will enhance the benefits to the body and are called synbiotics (Audet et al., 1988). The role of prebiotics in enhancing prebiotic viability has been reported in many previous studies (Chandramouli et al., 2004). However, research on combinations of prebiotics to enhance the protective effects of probiotics has not been fully reported. Therefore, in this study, the effect of prebiotic Galactooligo Saccharide (GOS) (0% and 2% w/v) on the viability of microencapsulated L. casei by 10% whey protein (w/v) and maltodextrin 5% (w/v) by spray drying technique was investigated. The composition was checked for size, surface structure as well as density of L. casei during 50 days of storage at 10oC and under gastric conditions (SGF) and bile salts (SIF).
References
Audet, P., C. Paquin and C. Lacroix (1988). “Immobilized growing lactic acid bacteria with κ-carrageenan — locust bean gum gel.” Applied Microbiology and Biotechnology 29(1): 11-18.
Chandramouli, V., K. Kailasapathy, P. Peiris and M. Jones (2004). “An improved method of microencapsulation and its evaluation to protect Lactobacillus spp. in simulated gastric conditions.” J Microbiol Methods 56(1): 27-35.
Charles, D. and D. Ruth (1998). “The biotechnology of lactic acid bacteria with emphasis on applications in food safety and human health.” Agricultural and Food Science 7(2).
Dimantov, A., M. Greenberg, E. Kesselman and E. Shimoni (2004). “Study of high amylose corn starch as food grade enteric coating in a microcapsule model system.” Innovative Food Science & Emerging Technologies 5(1): 93-100.
Gill, H. S., K. J. Rutherfurd, M. L. Cross and P. K. Gopal (2001). “Enhancement of immunity in the elderly by dietary supplementation with the probiotic Bifidobacterium lactis HN019.” Am J Clin Nutr 74(6): 833-839.
Jankowski, T., M. Zielinska and A. Wysakowska (1997). “Encapsulation of lactic acid bacteria with alginate/starch capsules.” Biotechnology Techniques 11(1): 31-34.
Kailasapathy, K. (2002). “Microencapsulation of probiotic bacteria: technology and potential applications.” Curr Issues Intest Microbiol 3(2): 39-48.
King, A. H. (1995). Encapsulation of Food Ingredients. Encapsulation and Controlled Release of Food Ingredients, American Chemical Society. 590: 26-39.
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Đăng ngày: 24/07/2020