Microencapsulation of Limonene by Freeze Drying: Effect of Type and Concentration of Wall Material

Document Type : Research Article

Authors

Masoud Najaf Najafi

Rassoul Kadkhodaee

Research Institute of Food Science and Technology (RIFST)

https://doi.org/10.22067/ifstrj.v7i3.10127

Abstract

Limonene is one of the widely used natural flavorings in the food industry. This compound has high volatility and sensitivity to oxidation and hence a significant portion of it is lost during processing and storage of foods. This work was, therefore, aimed at microencapsulating D-limonene by using freeze drying. To this end, oil-in-water emulsions composing of 10% limonene (wall material basis) in an aqueous solution of 2, 5 and 10% sodium caseinate or modified starch (capsul) was prepared by ultrasound. The influence of the type and concentration of wall material on the properties of freeze-dried microcapsules such as percent of oil retention, surface oil content, encapsulation efficiency, moisture content and release rate of oil was evaluated. Comparison of microcapsules characteristics revealed that those made up with 10% modified starch could retain more limonene than those containing sodium caseinate or lower concentrations of modified starch with longer half-life over 6 weeks of storage at 25 °C.

Keywords: Microencapsulation, Sodium caseinate, Modified starch, Limonene, Freeze drying

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