Chapter Eighteen - Antioxidant activity analysis of nanoencapsulated food ingredients

Abstract

Encapsulation provides the easy dispersibility of antioxidants in all food matrices; it can improve the food fortification process, release of antioxidant ingredients, and extend the shelf-life and bioavailability of them when ingested in the intestine. Wall material can participate in antioxidant reactions; therefore, it can raise antioxidant activity of encapsulated antioxidants. Encapsulation processing can decrease the antioxidant activity of core materials because of coating them within the wall materials or degradation of sensitive compounds during the encapsulation process. Analytical techniques for measuring the antioxidant activity of encapsulated ingredients are spectroscopic methods (FRAP, DPPH, ABTS, HORAC, ORAC, TRAP, CUPRAC, PFRAP, Folin-Ciocalteu method, fluorimetry), electrochemical techniques (amperometric, cyclic voltammetric, biamperometric, and biosensor techniques), chromatographic techniques (HPLC, GC, TLC), and cellular antioxidant activity (CAA). Among them, DPPH, total phenolic compounds (TPC), ABT, ORAC, and CUPRAC are used more than the other techniques to evaluate the bioactivity of nano/microencapsulated food ingredients, since these methods are simpler, more effective, and quicker than other ones. In this chapter, a brief overview of the mentioned techniques will be presented along with the relevant studies in measuring antioxidant activity of nanoencapsulated food ingredients.