Starch dextrins, encapsulation

Initial work began with testing various starches for encapsulation properties. Low viscosity, stable starch dextrins were first evaluated versus gum arabic for encapsulation efficiencies. Dispersions of corn and tapioca dextrins were used to encapsulate single fold orange oil. 

One sees from the data, presented in TABLE 1, that the starch dextrins have the ability to encapsulate the orange oil, but does not encapsulate as much oil as gum arabic. 

The starch dextrins match the viscosity and stability of the gum arabic when placed in solution, however other properties such as emulsifying and emulsion stabilizing properties are poorer in the dextrins. We believe that the emulsifying properties inherent in gum arabic are partially responsible for its encapsulating abilities. 

Gum arabic, standard starch dextrins and laboratory prepared low viscosity starch octenylsuccinates were used for all encapsulation work. 

Emulsions of lemon oil stabilized with gum arabic, a conventional starch dextrin and a low viscosity starch octenylsuccinate were spray-dried and evaluated for encapsulating efficiencies. Oil retentions and surface oil determinations were made according to the Materials and Methods section. TABLE 3 demonstrates the superiority of the starch octenylsuccinate in flavor retention and surface oil to gum arabic and a starch dextrin (5) ... 

As can be seen from the data in TABLE 5 the low viscosity starch octenyl-succinate closely matches the oxidation resistance of gum arabic. This product would offer improved shelf-life over a standard starch dextrin and similar stability to a gum arabic encapsulated flavor. 

In the food industry, because the spray dryer is commonly available, economical, fast, and produces good-quality material [16], it becomes the most common means of encapsulation. The encapsulation process is simple and similar to the one-stage spray drying process. The coated material is called the active or core material, and the coating material is called the shell, wall material, carrier, or encapsulant [43]. The active material to be encapsulated, such as an oil or fia-vor in an oil base, is dispersed in a hydrocolloid carrier, e.g., gelatin, modified starch, dextrin or maltodextrin, or gum arabic. After the emulsifier is added, the mixture must be... 

Viability of Starch Derivatives as Flavoring Encapsulants. The capillary GC vapor phase flux term (defined by a percent external standard or ZEStD flux) previously described (34) was used to screen starch derivatives (oxidized, dextrinized and/or covalent amino acid linkage) as to their flavor encapsulation potential. The samples were prepared as previously described (34) with the exception of an added reduced pressure deaeration step, thus allowing the use of the headspace diffusivity versus retention standard curves to predict volatile lemon oil retention following spray drying. 

---