Comparative study on efficiency of nutmeg microencapsulation (freeze‐drying method) using native and OSA sorghum starch as wall materials in combination with gum arabic

Abstract

AbstractBackground and objectivesNutmeg oleoresin (Myristica fragrans Houtt.) is used widely in the culinary, medicine, and ornamental products and is known for significant antioxidant, antifungal, antimicrobial, and pharmacological properties. Quality of nutmeg oleoresin can be retained through encapsulation techniques which suppresses the degradation of flavoring ingredients. The main objective of this research was to estimate the suitability and feasibility of sorghum starch (native and octenyl succinic anhydride) as shell material in combination with gum arabic.FindingsMost of the emulsion formulations showed better stability after 24 hr. The freeze‐dried nutmeg microcapsules had excellent flow properties. The freeze‐dried powdered samples showed flake‐shaped microgranules with various sizes with no apparent cracks and holes on external surfaces. The studied wall matrices comprising 1 portion of sorghum starch with 2 portions of gum arabic resulted in high oil retention (99.4%), while GA:OSA showed the highest encapsulation efficiency (92.87%). The sample composed of 1:2 ratio of gum arabic with OSA starch resulted in the lowest peroxide value after 60 days of storage.ConclusionIn the current study, coating materials arabic gum, sorghum native starch, and modified OSA starch worked as potential source to encapsulate nutmeg oleoresin by freeze‐drying. The highest encapsulation efficiency of 92.87% with lower surface oil (0.33 g/10 g) was obtained by gum arabic and native starch in a ratio of 1:3.Novelty and significanceThe research introduces the sorghum starch (native and OSA‐modified form) as innovative wall material for microencapsulation of nutmeg oleoresin using freeze‐drying method with remarkable encapsulation efficiency.