5.2.3.5 Agbelima
Agbelima is a fermented product popular in the Ivory Coast and Ghana. It is used in the preparation of a wide range of traditional meals including banku, akple and kenkey, and can easily be produced in larger quantities at a relatively low cost (Ellis et al., 1997). The production of agbelima involves the use of an inoculum, locally called kudeme. Many different methods exist for the processing of kudeme. The main purpose for using this inoculum is for souring and texture degrading, which helps to improve the texture, colour and flavour (Sefa-Dadeh, 1989). The cassava roots are peeled, steeped in water for initial fermentation and then ground to paste like fufu and the paste is again left to ferment for 2 days in jute sacks and then pressed. Finally, the paste is removed from the sacks, crumbled or granulated, and then steamed. The difference from fufu preparation is the steaming step in the final stages. Microflora for fermenting cassava dough into agbelima showed a dominance of LAB consisting of species of Lactobacillus, including Lb. brevis, Lb. plantarum and Leuconostoc mesenteroides, as well as yeasts such as Candida krusei, C. tropicalis and Zygosaccha-romyces bailii (Amoa-Awua et al., 1996,1997; Kofi et al., 1996). Studies conducted by Mante et al. (2003) demonstrated the inhibitory effect of LAB against different enteric pathogens during the fermentation of cassava dough into agbelima. Vibrio cholerae C-230, Salmonella typhimurium 9 and Salmonella enteritidis 226 were not detectable in 10 g of sample after 4 h, when inoculated into the 48 h fermented product, agbe-lima. The inhibitory effect was attributed to the acid production by LAB. Sensory attributes like colour, smoothness, cohesiveness, aroma and sourness determined consumer acceptability of agbelima (Dziedzoave et al., 1999).
5.2.3.6 Attieke, Placali and Kivunde
Attieke and placali are two other cassava-fermented products consumed in the Ivory Coast and neighbouring countries (Firmin, 1995). Attieke is similar to agbelima but has a slightly sour taste and is eaten with milk or meat or vegetables. To produce attieke, cassava roots are peeled, cut into pieces, washed and grated. During grating, the cassava mass is mixed with 10 % of a traditionally prepared inoculum and about 0.1 % palm oil. The inoculum is prepared by storing boiled cassava roots for three days in an unwashed jute bag previously used for inoculums preparation. The inoculated pulp is fermented overnight in covered bins. After fermentation, the pulp is filled into bags and pressed for several hours. The pressed pulp is taken from the bags and squeezed through a sieve to obtain granules that are sun-dried and then cleaned to remove fibres and waste. The dried granules are steamed to produce attieke, which is sold in small plastic bags as a ready-to-eat food. In the inoculum as well as at the start of fermentation, LAB such as Leuconostoc mesenteroides subsp. mesenteroides and Enterococcus faecalis were found as the dominant species (Coulin et al., 2006). Attieke was originally prepared and consumed exclusively by some ethnic groups in the Ivory Coast. In recent years, the product has become popular among urban consumers beyond the boundaries of the Ivory Coast, because of its suitability as convenient fast food, which is either consumed hot or cold (Assanvo et al., 2006). Attieke and placali are generally produced by fermentation of bitter cassava roots and the fermentation is controlled by several microorganisms, some of whom have positive effects such as product preservation, flavour development, cyanide reduction and changes in functional properties (Abodjo et al., 2010). Kivunde is another traditional fermented food from cassava that is popular in Tanzania (Kimaryo et al., 2000).
5.2.3.7 Abacha (Wet Cassava Chips)
Abacha or Akpu-mmiri, or wet cassava chips, are a popular fermented cassava snack product of south-eastern Nigeria. To prepare abacha, the cassava roots are washed, peeled, boiled in water for about 1 h and cut into longitudinal slices or chips. These chips are soaked in water for l-2 days, during which the water may be changed once or twice. At the end of fermentation (during which the taste of the chips becomes almost bland), the chips are removed, washed two or three times with fresh cold water for consumption (Iwuoha and Eke, 1996).
5.2.3.8 Tapai
Tapai is a well-liked Indonesian delicacy prepared by fermenting glutinous rice or cassava roots. Fermented glutinous rice is named tape ketan, while fermented cassava is named tape ketella (Indonesian), tape telo (Javanese) or peujeum (Sundanese). Both are produced in Indonesia on a home industry scale by traditional manufacturers or at home for family consumption. To prepare Tapai from cassava, roots are cut into pieces, smeared with ragi (a mixture of flour and spices in which yeast and fungi have been active), and either wrapped in banana leaves or placed unwrapped in a tray for 5–7 days. During fermentation, moulds such as Chlamydomocular oryzae converts starches to sugars, and yeast such as Endomyces fibuligera converts sugars to alcohol and flavour components (Beuchat, 1987). The tapai has a refreshing and slightly alcoholic flavour and is eaten either as it is or after baking. There are many recipes with tapai as the main substrate. The cassava tapai is ground, mixed with brown sugar, moulded into balls, dipped in flour and deep fried. The cassava tapai is ground, mixed with ingredients, wheat flour, and egg, moulded, sprinkled with shredded cheese and baked as a cake (cheese tapai cake). Cassava tapai is also cooked in coconut milk with palm sugar and pandanus leaves and consumed as a delicious snack (Gandjar, 2003). The microorganisms associated with cassava fermented foods are given in Table 5.1.
5.2.4 Novel Fermented Foods from Cassava
5.2.4.1 Fermented Sweet and Sour Flour
A technology has been developed at the Central Tuber Crops Research Institute (CTCRI), Thiruvanathapuram, India for extraction of fermented sweet and sour flour from cassava. In this process, a mixed starter culture (Lactobacillus cellobio-sus, Streptococus lactis, Corynebacterium sp. and Pichia membranaefaciens) was used to ferment cassava roots. It improved the extraction of starchy flour without liberating foul odours (George et al., 1995). This approach beneficially modifies the functional properties of the starch, while leaving the granular structure intact (Nanda and George, 1996). It also lowers the cyanide content, improves the shelf life, and gives better cooking qualities to the flour, especially the enhanced puffing characteristics suitable for bakery products (Balagopalan, 2000). Nutritional values and in vitro digestibility of the fermented cassava flour is much higher compared with non-fermented flour (Moorthy and Padmaja, 1995). The fermented cassava sweet and sour flours are used to make various bakery products such as bread, cakes, pastries, etc. (Balagopalan, 2000).