Xylooligosaccharides as an innovative carrier matrix of spray-dried natural blue colorant

Abstract

Xylooligosaccharides (XOS) are emerging prebiotic carbohydrates with a high potential to promote health and wellness due to their ability to modulate gut microbiota. Their use as a carrier of milk proteins-crosslinked genipin, an innovative natural blue colorant, was examined in this study. Fructooligosaccharides (FOS), a standard prebiotic carbohydrate, and maltodextrin (MD), a standard carrier material, were compared to XOS as wall materials. The effect of the carrier system on the powdered blue colorants was assessed regarding their size, morphology, free-genipin content, blue color intensity, moisture content, water activity, hygroscopicity, water adsorption, and physical structure. Their technological properties as food colorants were evaluated by incorporating in foodstuffs: beijinho, Chantilly, and muffin. XOS exhibited positive effects compared to other carriers evaluated. XOS-based microparticles presented higher free-genipin retention; smaller particle diameter equal to 6.5 ± 0.4 μm, and higher blue color intensity. The microparticles produced with XOS were more hygroscopic compared to other carrier matrices. However, similar to FOS and MD, the blue colorant carried with XOS presented an amorphous structure. XOS was the best carrier in food applications due to the less interference on the blue color in the powder colorant. The XOS microparticles could be easily incorporated into some food matrices. Therefore, spray-dried blue colorant using XOS presented significant innovative potential in many food products, acting as a functional ingredient, replacing artificial blue colors, and incorporating prebiotic properties.