**4. Textural attributes of cooked gari (***eba***) and possible influence of pectin**

Gari is a roasted, fermented cassava grit, consumed raw, soaked in cold water, or reconstituted in hot water into *eba*, and is common in the diets of millions of people in developing countries [20]. The instrumental texture attributes of *eba* produced from different cassava varieties reported by Awoyale et al. [20] showed that variations exist in their textural attributes. For instance, the hardness of the *eba* was higher in TMS15F1467P0011 gari (54.58 N/m2 ) and lower in TMS14F1035P0004 gari (13.71 N/m2 ) (**Table 1**). This means that consumers that prefer the firm-textured *eba* can consume the *eba* prepared from the TMS15F1467P0011 gari, while those that prefer the soft-textured *eba* can consume the *eba* prepared from the TMS14F1035P0004 gari. This was in agreement with the hardness of the *eba* prepared from different cassava varieties using the backslopped fermented gari (21.03–30.22 N/m2 ) [3]. Hardness is defined as an indicator of the most direct response to taste, which has a direct relationship with chewiness, gumminess, and cohesiveness in the texture profile analysis [3]. It was reported by Zhai et al. [22] that the hardness of the blends of waxy rice starch and pectin gels significantly decreased with the increase in pectin inclusion. The authors attributed this observation to the fact that the pectin formed hydrogen bonds with the waxy rice starch molecules, which interfered with the formation of ordered structures during starch retrogradation. This implies that the pectin content in the TMS14F1035P0004 gari may be high and that of the TMS15F1467P0011 gari may be low, hence the lower hardness of the *eba* prepared from TMS14F1035P0004 gari [22]. This observation was also supported by Gafuma et al. [23]. These researchers reported that pectin contributes to a softer texture of bananas during cooking and cooling, which was attributed to the high water retention capacity of pectins. In addition, the high water binding and holding capacity of pectins may keep the cooked banana structural matrix moist, thus maintaining starch in a gelatinized state, hence making pectin-treated bananas relatively soft in a cooled form [23].

The degree to which the *eba* sticks to the hand, mouth surface, or teeth is known as adhesiveness [3]. The adhesiveness of the *eba* ranged from −177.50 N/m2 to −39.36 N/m2 , with TMS13F1343P0004 gari having the highest and TMS15F1482P0098 gari the lowest (**Table 1**). This implies that the *eba* prepared from the TMS13F1343P0004 gari may be more adhesive compared to that prepared from the TMS15F1482P0098 gari [3]. Zhai et al. [22] reported that the decrease in adhesiveness in the blends of waxy rice starch and pectin gels with the increase in the pectin content may be associated with the covering of the starch molecules by the pectin, resulting in reduced starch-to-starch hydrophobic interaction. Consequently, the low adhesiveness of the *eba* prepared from TMS15F1482P0098 gari may be attributed to the high pectin content. This is because the lower hydrophobic interaction might have led to inhomogeneity and instability in the network structure of the *eba*, thus reducing the textural characteristics [22].

Usually, the *eba* is squeezed manually, during which the mechanical and geometrical characteristics are assessed, molded into balls with the hand, dipped into the soup, and then swallowed [3]. Hence, moldability is how well the product withstands a second deformation relative to its resistance under the first deformation [3]. The *eba* from TMS13F1053P0010 gari (0.89) had the lowest moldability, and the IITA-TMS-IBA980581 gari (0.98) had the highest moldability (**Table 1**). A similar range of values (0.84–0.98) was reported for the moldability of *eba* prepared from backslopped fermented gari [3]. The high moldability of the *eba* from IITA-TMS-IBA980581 gari may be linked with increased pectin concentration upon cooking and cooling, which may be attributed to the retrogradation of starch [23].


*Cassava Pectin and Textural Attributes of Cooked gari (*eba*) and fufu Dough DOI: http://dx.doi.org/10.5772/intechopen.109580*

*Means with the same letters within the same column are not significantly different (p < 0.05);*

*\*p < 0.05;*

*\*\*p<0.01*

*Values are means of six replicates. Source: Awoyale et al. [21].*

#### **Table 1.**

*Instrumental texture attributes of* eba *produced from different cassava genotypes.*

For consumers that chew *eba* before swallowing, the stretchability is the degree to which the *eba* returns to its original shape after compression between the teeth [3]. The stretchability was higher in the *eba* prepared from the TMS15F1466P0195 gari (1.14) and lower in the *eba* prepared from the TMS14F1287P0008 gari (0.91) (**Table 1**). The high stretchability of the *eba* from the TMS15F1466P0195 gari may be due to the gari's high peak and breakdown viscosities [3]. However, the values of the stretchability of the *eba* prepared from backslopped fermented gari (0.88–1.06) fall within the values of the stretchability of the *eba* in this study [3].

Gumminess is also defined as the energy required to disintegrate a semi-solid food until it can be swallowed [3]. The gumminess of the *eba* ranged from 12.98 to 52.10 N/m2 . *Eba* prepared from TMS14F1035P0004 gari had the lowest gumminess, and the *eba* from TMS15F1467P0011 gari had the highest gumminess (**Table 1**). The gumminess of the *eba* prepared from the backslopped fermented gari (20.54–27.10 N/m<sup>2</sup> ) falls within the values of the gumminess of the *eba* in this study [3]. The low gumminess of the *eba* prepared from TMS14F1035P0004 gari may be due to the low hydrophobic interaction that might have led to inhomogeneity and instability in the network structure of the *eba*, thus reducing the textural characteristics [22].
