**2. Functional-antioxidant food - concept and classification**

## **2.1 Concept**

Functional-antioxidant food is food containing one or more antioxidant substances extracted from plants or animals or synthesized. Bioactive substances belong to the group of protein, carbohydrate, or secondary metabolites.

#### **2.2 Classification**

Functional-antioxidant food could be classified according to different criteria, for example, shape or bioactive ingredient style. Classification of functionalantioxidant food follows their shape are susceptible to drug classifications. Hence, functional-antioxidant food classification base on their bioactive ingredient style (**Figure 1**). Functional-antioxidant food is mainly three large groups (protein, carbohydrates, and secondary metabolites. The current chapter presents antioxidant substances commonly used in the manufacture of functional-antioxidant food such as such as collagen, pectin, alginate, fucoidan, laminarin, inulin, glucosamine, ulvan, chondroitin, polyphenol, lignin, alkaloid, and flavonoid.

**Figure 1.** *Classification of functional-antioxidant food.*
