Nano- and micro- encapsulation of curcumin by spray drying technique: characteristics and applications in food

Abstract

Curcumin (CUR) is an important natural polyphenol, extracted from the rhizome of Curcuma Longa used for thousands of years by the Asian population, both as a food ingredient (dye, preservative, spice) and as a remedy for certain gastrointestinal diseases, inflammation, cataracts, and bacterial infections. Unfortunately, CUR, like many polyphenols, has a low bioavailability due to its low water solubility, chemical instability at pH variations, low cell absorption, and rapid metabolism. To overcome these challenges, many researchers have applied various CUR encapsulation techniques. In this study, an overview of the principles and conditions for nano/micro-encapsulation of CUR through the spray-drying has been presented. Different biopolymers including polysaccharides and proteins have been utilized for this purpose. For nanoencapsulation of CUR, an innovative spray-drying technique has recently been developed, the so-called nano-spray-dryer, whose operations and advantages are briefly discussed in this paper too. The results from the literature on the optimization of physico-chemical and technological parameters, the nature of encapsulating materials, and the characteristics of the spray-dried CUR-loaded powder particles are also highlighted. Finally, the applications of spray-dried CUR powders in food functionalization with the focusing on the antioxidant, antimicrobial, and coloring properties are described.