Cassava retting: Optimisation of a traditional fermentation by an experimental research methodology

Abstract

Retting, a spontaneous and traditional fermentation of cassava roots in Central Africa, was optimised in terms of time and the quality of the endproduct. Optimal conditions were achieved by using an experimental research methodology. Temperature is the most influential factor, with an optimum of 34°C for quicker retting. The roots should be peeled and soaked in water immediately after harvesting to increase the quality of cassava foods. Inoculation of water with juice from a prior retting helps in cassava detoxification but has no influence on the time or the quality of foo-foo. Foo-foo samples had the most favourable organoleptic quality when an incubation temperature of between 28 and 37°C was used. Using optimal conditions, retting time was reduced 3-fold, and foo-foo of high and constant quality could be processed.

The effects of processing techniques in reducing cyanogen levels during the production of some Cameroonian cassava foods

“…o15 mm) during the first 48 h of fermentation for the production of Nigerian fufu, which also affected product organoleptic qualities (Oyewole, 1994). The reduction in cyanogen levels has been found to be strongly correlated to the degree of root size reduction, which is also directly related to the rate of softening and acidification (O'Brien et al, 1992;Ampe et al, 1994;Westby and Choo, 1994).…”

“…Cooke (1979) reported that the optimum pH and temperature of linamarase activity are 5.5-6.5 and 30 1C, respectively. It has been observed that soak-water temperatures of 30-37 1C caused high rates of acidification, shorter periods of soaking (at least 60 h), high cyanogen reduction levels and acceptable product organoleptic qualities (Oyewole and Odunfa, 1992;Ampe et al, 1994). Studies on Nigerian lafun and fufu production have shown that a soaking period of about 40-60 h and temperature range of 30-35 1C were best conditions for submerged fermentation products, while other variables such as root size, age of the roots, and changing of the soak waters have effects on product quality (Oyewole, 1994).…”

Microbiological and biochemical characterization of cassava retting, a traditional lactic Acid fermentation for foo-foo (cassava flour) production

“…Retting of cassava entails steeping roots in water for 3 to 4 days. During the consequent fermentation, roots are softened (34), the endogenous cyanogenic glycosides (linamarin and lotaustralin) are degraded (3), and characteristic flavors develop (1,36). In the West and in Asia, retting is used for the treatment of certain Malvaceae, such as linen flax (7), and other plants, such as cucumber (39).…”

“…These products provide almost 50% of the caloric intake of the population (47). Despite the economic importance of these processed products, most of the published work on cassava retting has focused on the detoxification of the cyanogenic glycosides during fermentation (2,3,14,27) or the influence of bacterial inoculation on foo-foo flavor and root softening (1,34,36). In previous studies on the microbiological aspects of this fermentation for production of foo-foo (34) or related products (9,37), aerobic or air-tolerant microorganisms were counted or isolated but strict anaerobes were not considered.…”

Influência da tempertura, tempo e concentração de pectinase na textura, rendimento e características físico-químicas da mandioca (Manihot esculenta C.) durante fermentação.

“…Durante a fermentação da puba, Almeida et al (1987), verificaram que o processo fermentativo pode ser acelerado empregando-se em vez das raízes inteiras, pequenos fragmentos colocados em água a temperaturas próximas a 30ºC. Trabalhos realizados para obtenção de fufu por Okafor et al (1984) sugerem que o tamanho da raiz afeta a velocidade de maceração, porém Ampe et al (1994), trabalhando com raízes inteiras concluíram em seus experimentos que esse fator não tem efeito significativo na velocidade deste processo. Assim como outras variáveis como o tempo de estocagem, a retirada da película externa e a variedade da mandioca parecem ter pouca ou nenhuma influência na velocidade de maceração para produção de fufu.…”