DANYANG YING, LUZ SANGUANSRI, MARY ANN AUGUSTIN*

*Corresponding author

CSIRO Food & Nutrition, 671 Sneydes Road, Werribee, VIC 3030, Australia

Abstract

Microencapsulation is a technology that protects sensitive ingredients against degradation.
The development of microencapsulated nutrients has enabled their stabilisation in liquid and powdered formats. While they have been successfully incorporated into powdered blends and some processed foods, the successful incorporation of sensitive nutrients into extruded products remains a significant challenge. This is due to the high temperature and shear encountered during the production of extruded products. Another application of interest is the use of microencapsulated ingredients in tablet form using generally regarded as safe (GRAS) ingredients. Microencapsulated ingredients need to be robust enough to withstand physical stresses during extrusion and tabletting. We discuss recent developments in our laboratory that have resulted in superior microencapsulated ingredients for improved delivery of lipophilic nutrients in these applications.

INTRODUCTION

Microencapsulation is a process by which an active component (core) is packaged within a secondary material (encapsulant) to form a microcapsule. Microencapsulation has wide ranging applications including its use for masking bitter flavours (e.g. peptides), protecting flavours prone to degradation (e.g. essential oils), and controlling the release of functional ingredients (e.g. anti-microbials, leavening agents). Microencapsulation is also used to protect nutrients against degradation and enable their delivery to target sites in the body after ingestion. Microencapsulation technology has been effective in the delivery of sensitive ingredients such as omega-3 fatty acids, vitamins, probiotics and polyphenols. The sensitive ingredients need to be protected at all stages of the production and during storage. The encapsulant material which surrounds the bioactive components, protects these sensitive ingredients against environmental stresses by isolating them from the surrounding environment until its release is triggered at a desired site and time. The chosen encapsulant material and the encapsulation process used h ...