Oleogel emulsions as a potential delivery system of probiotics

Abstract: The food industry is currently researching oleogels and oleogel emulsions and how they can improve probiotic stability in food systems. The purpose of this study is to design and develop an oleogel emulsion as a delivery system for probiotics via oleogel emulsion encapsulation. The aim of this work was to evaluate oleogel emulsion combinations that had a primary oleogelator of beeswax, and structured with a secondary oleogelator of glycerol monostearate in combination with 100 ml soybean oil. The texture, DSC, rheology, PLM, visual and OBC analysis results indicate that oleogels composed in a 7:3 ratio between beeswax and glyceryl monostearate had a desired stability range between 45-50 ℃. The oleogel texture showed a firmness of 204.3±13.8g and a toughness of 502.4±50.0 g.mm. The oleogel retained 100% of the oil after 60 days. The melting curves presented T_on (Onset Temperature) of 37.5±0.4 ℃, with a T_p (peak temperature₎ at 51.8±0.3 ℃, and a DH of 8.4±0.1J/g). The soybean oleogel emulsion experiments tested different ratios of emulsifiers including Tween 80, phospholipon, and lecithin in ratios of (0.5, 1, 1.5, 2%) and ionized water at ratios of (5, 10, 15%). Results of texture, visual, and OBC analysis indicated that oleogel emulsions containing beeswax: glycerol monostearate oleogel added with 0.5% of Tween 80 and 10% of water presented a significant potential as a probiotic delivery system due to its physical stability. The Tween 80 oleogel emulsion retained 69% stability after 60 days and the texture resulted in a firmness of 304.1±50.9g and a toughness of 685.0±95.2g.mm. Preliminary probiotic testing indicated increased viability. This study is beneficial because it provided a new alternative of delivery systems for food scientists, and facilitated the challenge of probiotic viability in oleogels systems.