Microstructure of Microcapsules Consisting of Whey Proteins and Carbohydrates

Abstract

Microstructure was studied on spray‐dried microcapsules with wall systems consisting of mixtures of whey protein isolate (WPI) and maltodextrins (DE 5, 10, 15) or corn syrup solids (DE 24). Structure of microcapsules was appreciably affected by type of carbohydrate and by the WPI‐to‐carbohydrate ratio. The extent of surface indentation was inversely related to the proportion of WPI in the wall system. Ratio of low‐to‐high molecular weight solutes in the wall system affected structure. At a WPI‐to‐carbohydrate ratio of 1:1 or higher, whey proteins improved the surface‐smoothness and decrease surface indentation of maltodextrin‐based microcapsules. Combinations of WPI with high‐DE value carbohydrates were more effective than those with carbohydrates of low DE value in limiting surface‐dents formation.

The effects of rheological properties of wall materials on morphology and particle size distribution of microcapsule

“…The decrease in ME may have resulted from the wall material being insufficient to produce a sufficiently strong structural matrix, and from insufficiently thick layers of the wall material between the encapsulated oil droplets (Hogan et al 2001). ME improved with increasing total solids concentration, which confirms the findings of the colleagues (Sheu & Rosenberg 1998). However, an increase of total solids concentration in the wall materials led to a higher viscosity of the emulsion, causing spray-drying to fail.…”

“…Almost all microcapsules produced with HI-CAP 100 presented surface dents, which was attributed to the mechanical atomisation, drying, and cooling solidification involved in spray-drying (Rosenberg et al 1985). During spray-drying, rapid cooling generated dents due to the wall material shrinkage, especially at high drying rates (Sheu & Rosenberg 1998;Teixeira et al 2004). Sheu and Rosenberg (1998) reported that whey proteins improved the surface smoothness and decreased the surface indentation of maltodextrin-based microcapsules.…”

“…During spray-drying, rapid cooling generated dents due to the wall material shrinkage, especially at high drying rates (Sheu & Rosenberg 1998;Teixeira et al 2004). Sheu and Rosenberg (1998) reported that whey proteins improved the surface smoothness and decreased the surface indentation of maltodextrin-based microcapsules. Combinations of whey protein isolates (WPI) with high-DE carbohydrates limited the surface dent formation better than those with low-DE carbohydrates.…”

“…Microencapsulation has become an attractive approach to transform liquid foodstuffs into stable and free-flowing powders for more convenient incorporation into dry food systems (Teixeira et al 2004). It also often involves a variety of biopolymers derived from natural gums, proteins, modified starches, and their blends (Sheu & Rosenberg 1998;Adhikari et al 2003;Muthukumarasamy et al 2006). These biopolymers serve as wall materials with desirable properties such as a good solubility, but they differ in interfacial functionality and rheological properties (Fortuna et al 2004;Weinbreck & Wientjes 2004;Norziah et al 2006).…”

Profile of Spray-Dried Emulsions Stabilised by Milk Proteins

“…Sheu i Rosenberg [45] analizowali wpływ równoważnika glukozowego DE maltodekstryny (5, 10, 15 i 24) i proporcji izolat białek serwatkowych : maltodekstryna (1 : 19, 1 : 9, 1 : 1, 3 : 1) na strukturę mikrokapsułek suszonych rozpyłowo emulsji zawierających 30 % oleju kokosowego. Stwierdzono, że cząstki o większej gładkości, mniejszym zakresie powierzchniowych wgłębień i wcięć uzyskuje się przy proporcji izobat : maltodekstryna 1 : 1 lub 3 : 1 oraz wyższym równoważniku DE.…”