The chemical analysis of encapsulated flavors poses unique problems due to the presence of the encapsulating wall material. The importance of chemical and instrumental analyses of encapsulated flavors in quality control and product evaluation cannot be over-emphasized. Barring a brief mention of surface oil determination by simple solvent extraction and total oil determination by steam distillation of encapsulated lemon oil, there is little scientific literature directed towards methods of analysis of encapsulated flavors. This investigation was undertaken to assess the applicability of existing methods and to develop new methods for analyzing encapsulated orange peel oil. The determinations evaluated were moisture content, total oil, surface oil and peroxide value.
Maltodextrin samples (4, 10, 20, 25 and 36.5 DE, referred to as 040, 100, 200, 250 and 365, respectively) were obtained from the Grain Processing Corporation (Muscatine, IA), and cold pressed orange peel oil was obtained from Universal Flavors (Indianapolis, IN). All organic compounds or solvents and inorganic chemicals used in the analyses were ACS certified grade.
Encapsulation of Orange Peel Oil
Maltodextrin solutions with 30 percent (w/w) solids content were allowed to hydrate overnight. Orange peel oil (20% w/w of solids) was emulsified into the carbohydrate solution using a laboratory homogenizer. The emulsion was immediately fed to a Niro Utility Model spray drier equipped with a centrifugal wheel atomizer. Operating at an inlet and outlet air temperature of 190 ± 3°C and 90 ± 30°C, an evaporative capacity of 6 Kg/hr, was obtained. The powders were stored in airtight glass jars at 4°C prior to analysis.