Casein-maltodextrin conjugate as an emulsifier for fabrication of structured calcium carbonate particles as dispersible fat globule mimetics

Abstract

Dispersible fat globule mimetics (FGMs) are demanded in manufacturing reduced fat products. The objective of the present study was to fabricate a group of FGMs with calcium carbonate particles (CCPs) as the core, coated with two sequential layers of anhydrous milk fat (AMF) and milk protein. The fabrication involved two steps: emulsifying an oil phase with CCPs suspended in AMF into an aqueous phase with dissolved emulsifiers to create an S/O/W suspension and spray drying the suspension. Experimentally, CCPs were suspended at 20–33.3% w/w in melted AMF at 80 °C that was then emulsified at 5% w/v into a neutral aqueous phase with 5% w/v sodium caseinate (NaCas), 10% w/v casein–maltodextrin (MD) conjugates, or 5% w/v NaCas and 5% w/v MD. Particle structures, encapsulation performance, and properties of skim milk hydrated with spray-dried powder were studied. The casein-MD conjugate treatment had the smallest particles (3.25 μm), the best encapsulation performance, and the best stability in skim milk (an increase of particle size by 30.5% after 10-day storage at 5 °C). Overall, casein-MD conjugates are better emulsifiers than NaCas in preparation of the studied FGMs that may be used to simultaneously improve sensory properties and increase the calcium content of reduced-fat products.