*3.1.2.1. Anthocyanins*

**Concentration of phenolic acids (µg/g of dry sample)**

**Maize grain color** *p***‐Hydroxybenzoic**

White Yellow Yellow

Red Mexican blue American blue

Purple

8460 **Table 1.** Concentrations of some phenolic acids in maize grain with different colors.

1.3

3.7

4.5

11.5

18.9 319.90

1.15 58.6 Traces

14610

Pedreschi and

Cisneros [19]

1237.5

428.4

2712.58

5.1

2123.2

95.7

230.1

4543.2

 **Vanillic**

**Caffeic**

**Syringic**

*p***‐Coumaric**

34.4

4841.4

18.4

 **Ferulic**

**Protocatechuic**

 **Reference** Del Pozo‐Insfran

et al. [27]

Das and Singh

[13]

Sosulski et al. [20]

Zilic et al. [22]

220 Phenolic Compounds - Natural Sources, Importance and Applications

Del Pozo‐Insfran

et al. [27]

Del Pozo‐Insfran

et al. [27]

Anthocyanins are a class of water‐soluble flavonoids that are visible to the naked eyes. They are glycosides of polyhydroxy and polymethoxy derivates of 2‐phenylbenzopyrylium or fla‐ vylium salts and are responsible for the red, purple, and blue colors of many fruits, vegetables, and cereal grains [23]. In maize grain, they are located in the pericarp, the aleurone layer, or in both structures [24]. Anthocyanins have sugars attached to the B‐ring at the 3′ and 5′‐hydroxyl position. The two most important types of glucosides are 3‐monoglycoside and 3‐4‐diglyco‐ side. As a rule, the 3‐hydroxyl always has a sugar, except in 3‐desoxypelargonidin, 3‐desoxy‐ cyanidin, and 3‐desoxydelphinidin [25]. The basic structure of the anthocyanidins present in maize grain is shown in **Figure 4**.
