**2. Production of gari and fufu**

Gari is a dry, crispy, creamy-white/yellow and granular product, which is produced by crushing the cassava root into a mash, fermented (lactic fermentation, optional in some locations), dewatered, and sieved into grits. The grits are then roasted manually or mechanically to make the gari [11]. However, the processing of cassava roots into gari differs from one location to another. Some producers/ consumers may prefer sour or bland taste gari, fine or coarse particle size gari, palm oil mixed gari, or even gari enriched/fortified with different legumes or protein sources [11–13].

Peeling of freshly harvested cassava roots manually with a knife is most common, but mechanical peelers are now available in countries such as Nigeria and Ghana [12]. The importance of the peeling process is to remove the brown peel, which might affect the gari color and increase its fiber content. Washing of the peeled roots is done to remove all extraneous materials, which could contaminate the gari. Grating of the washed cassava roots is done using a motorized cassava grater, but hand graters, made by fastening the perforated grating sheets on the wood, are still used in some countries. Grating is done to increase the surface area of the cassava root and free up the moisture so that dewatering of the mash can be done easily. The grated cassava mash is bagged using a polypropylene/polyethylene woven bag or basket (lined with

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

**Figure 1.** *Production of gari [11].*

a polypropylene sack) and left for between 1 and 5 days to ferment, depending on the taste preferred by the consumers. Apart from the taste, fermentation helps to reduce the cyanogenic potential of the product [12].

The fermented mash is then dewatered by pressing with a manual screw or hydraulic press or even wood tied at both ends with a rope, which is still common in most rural communities. Pressing is done to reduce the moisture content of the grated mash before roasting. The cake formed after dewatering is pulverized by a pulverizer/cake breaker or by hand and sieved with a manual woven sieve or rotary sieve, to remove the fiber and lumps. The sieved grit is then roasted, cooled, and packaged (**Figure 1**) [12].

An earthenware stove and a roasting pan made of molded aluminum or stainless steel are used for roasting on a wood fire. In some communities, the roasting pan is smeared with a small amount of palm oil prior to roasting, to produce yellow gari. However, mechanical roasters are now available in Nigeria and Ghana. The roasting

**Figure 2.** *Production of fufu powder [15].*

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

process develops the gari flavor and improves digestibility, and the extent of drying determines the crispiness and storability of the product. It is important to add that in some communities, the grit is partially toasted and finally dried under the sun, which is not very good as the product will be contaminated. The gari is then cooled for some hours, graded (sieved) depending on the particle sizes preferred by the consumers and packaged depending on the distribution outlet. However, most rural communities package in 50 kg bags for retail. The roasted gari can be consumed in the form of cooked dough (*eba*) with a preferred soup by reconstituting it in boiled water [14]; hence, the textural attributes are very important and may be influenced by the pectin content of the roots.

Fufu is produced by peeling the cassava roots using a stainless-steel knife, washing them with clean water, and soaking them in fermenting drums for four days. The fermented roots are then sieved through a muslin cloth and allowed to form sediment. The sediment is collected and packed in woven polyethylene sacks and dewatered using a manually operated pressing machine. The cake is pulverized and spread on a black polyethylene sheet for drying under the sun. The dried fufu is milled using a hammer mill, cooled, and packaged (**Figure 2**) [15]. Fufu can be sold in a wet form (a semi-solid cake) or in a flour form. Fufu is consumed by reconstituting in boiled water to form a cooked dough, which is consumed with preferred soup [15], thus the need for textural attributes of the fufu that may be affected by the pectin content of the cassava roots.

### **3. Influence of pectin on the textural attributes of cassava roots**

The texture of foods is related to the structure formed by micro- and macromolecular elements forming the cell wall and other regions [16]. Most of the textural changes in roots and tubers during processing are related to pectin and starch contents and the composition of the amylose/amylopectin ratio. Softening of cell walls during the cooking of cassava root was studied for intracellular compounds such as cations (Ca2+ and Mg2+), phytic acid, and pectins. It appeared that the cassava variety with the longer cooking time had a lower level of cations and phytic acid and higher levels of chelator-insoluble pectic polysaccharides. It is therefore likely that mealiness is associated with pectins in cassava roots [6]. Maieves et al. [17] reported that cassava varieties whose starch granules are more deeply related to parenchyma tissues, pectin, and cellulose tend to be harder in texture, both in raw and in cooked cassava roots. Infante et al. [18] added that the presence of pectic substances (salts of pectinic and pectic acids, and protopectin) in cassava root may contribute to the texture and hardness of cassava roots, which in turn could be responsible for the mouth feel of cooked or processed foods. A correlation between pectin composition and the cooking quality of boiled cassava roots provided the first evidence that pectins are involved in determining the texture of root and tuber products. In the case of boiled cassava, a soft texture was related to higher levels of methoxylated pectins (i.e., pectins with side groups limiting their ability to form egg-box complexes with Ca2+) and lower levels of nonmethoxylated pectins [19]. This was linked with higher pectin methyl esterase activity, which is associated with increased firmness as the pectin methyl esterase rapidly demethylates pectin in the cell walls and middle lamellae, allowing for hardening through cross-linking with divalent cations [19].
