Enriching nutritive value of cassava root by yeast fermentation

Abstract

Cassava (Manihot esculenta) is extensively cultivated throughout the tropics and subtropics regions due to its ability to grow in diverse soil conditions and minimal management. Experiments were made to study the cassava root fermentation by yeasts in order to enhance the nutritive value of their products (fresh pulp and chips). Both cassava chip (CC) and fresh cassava root pulp (FCR) samples were fermented by Saccharomyces cerevisiae in solid-liquid media fermentation conditions during 132 hours and dried at 30ºC. Products were analyzed for proximate composition, mineral composition, essential aminoacids and antinutrient content. There were increases (p < 0.01) in protein (30.4% in CC and 13.5% in fermented cassava root -FCR) and fat contents (5.8% in CC and 3.0% in FCR). S. cerevisiae fermented cassava products had very low hydrocyanic acid (HCN) contents (CC, 0.5 mg kg -1 and FCR, 47.3 mg kg -1 ). There was a remarkable increase in lysine content in the fermented cassava chip (FCC). The best acceptability and organoleptic attributes (color, texture and aroma) of enriched cassava chip were achieved after 132h of bioprocessing. The results of this study suggest that FCC can be nutritionally improved with S. cerevisiae for animal feeding. Key words: Saccharomyces cerevisiae, fermentation, cassava chip, fresh cassava root pulp, protein, animal feed ENRIQUECIMENTO DO VALOR NUTRITIVO DA MANDIOCA POR FERMENTAÇÃO COM LEVEDURASRESUMO: A mandioca (Manihot esculenta) é extensivamente cultivada nas regiões tropical e subtropical devido à sua habilidade de crescer em diveresas condições de clima e manejo. Experimentos foram efetuados para estudar o aumento do valor nutritivo de subprodutos derivados de raízes de mandioca (polpa fresca e raspas) por processos de fermentação. Amostras de raspas (RM) e de polpa fresca (PF) foram fermentadas por Saccharomyces cerevisiae, em condições de meio sólido-líquido durante 132 horas e secas a 30ºC. Foram avaliados a composição aproximada, composição mineral, aminoácidos essenciais e conteúdo de antinutrientes dos produtos obtidos. Houve aumentos (p < 0.01) em proteínas (30,4% em RM e 13,5% in PF) e conteúdo de gorduras (5,8% em RM e 3,0% in PF). Os subprodutos de mandioca fermentados por S. cerevisiae apresentaram baixos conteúdos de ácido hidrocianídrico (RM, 0,5 mg kg -1 e PF 47,3 mg kg -1 ). Houve aumento considerável de lisina nas raspas fermentadas (RMF). Valores aceitáveis de cor, textura e aroma das raspas de mandioca enriquecidas formam obtidos após 132 de bioprocessamento. Sugere-se que a RMF pode ser nutricionalmente melhorada para alimentação animal pelo uso de S. cerevisiae. Palavras chave: Saccharomyces cerevisiae, fermentação, raspas de mandioca, polpa fresca de mandioca, proteína, nutrição animal.

Bio-Ethanol Production from Non-Food Parts of Cassava (Manihot esculenta Crantz)

“…Other factors to consider are the different levels of cyanogenic glycosides and proteins in different parts of the cassava plants, which may have affected establishment of yeast in the solution. These compounds affect the growth of yeast in fermenting broth depending on whether they are metabolized by yeast or not, which directly affects growth and metabolism of yeast (Boonnop et al 2009;Klinke et al 2004). In particular, lignocellulosic materials in hydrolyzed leaves, stems, and peels may result in production of small molecular weight compounds such as furan derivatives, phenolic compounds, and amine-based compounds such as vanillin, all inhibiting fermentation (Endo et al 2008).…”

Improving Cassava Quality for Poultry Feeding Through Application of Biotechnology

“…Zvauya and Muzondo [81] concluded that there was a marked improvement in protein level following microbial fermentation of cassava with A. oryzae. There was a 13.5% increase in protein and a marked reduction in HCN after cassava root pulp was fermented by S. cerevisiae in solid-liquid media fermentation conditions during 132 h and dried at 30°C [71].…”

“…Cassava chip is an energy source with low crude protein, which when fermented with yeast could increase from 1-3% to 30.4% crude protein [71]. To obtain cassava products with high protein content and a relatively balanced amino acid profile for use in poultry feeding, cassava …”

Enrichment of protein content in cassava (Manihot esculenta Crantz) by<br>supplementing with yeast for use as animal feed

“…Recently, Oboh and Akindahinsi (2003) (reported that S. cerevisae could also be used for enriching cassava products. Boonnop et al (2009) demonstrated that supplementation of cassava chip with Baker's yeast (S. cerevisae) could increase crude protein from 2% to 32.4%. Moreover, Brewer's yeast (S. cerevisae) is by-product that can be produced in association with the production of beer, one of interesting microorganism used for enrichment of animal feed.…”