Potential application of monoglyceride structured emulsions as delivery systems of probiotic bacteria in reduced saturated fat ice cream

This study investigated the potentialities of saturated monoglyceride structured emulsions (MSEs) as delivery systems of probiotics in ice cream. MSEs containing a probiotic Lactobacillus rhamnosus strain were prepared using anhydrous milk fat (AMF-MSE) or sunflower oil (Oil-MSE) as lipid phase and were added to the ice cream mix in substitution to milk cream just before freezing. Results highlighted the good capacity of MSEs to protect probiotic bacteria cells against stresses suffered during processing and storage. The physical state of the lipid phase included in the emulsion did not affect the survival of microorganisms. At the same time, the use of MSEs as fat phase allowed to obtain ice cream with minor modifications in terms of quality characteristics in comparison to control sample. In particular, Oil-MSE demonstrated the ability to create a melt-resistant fat network structure in ice cream when milk fat was replaced with sunflower oil. It was concluded that the monoglyceride crystalline structures formed in the MSE played both probiotic protective and structuring role. This approach allowed obtaining a low-saturated fat ice cream functionalized with probiotic bacteria.