Evaluation of the Potentials of Some Cassava Varieties in Nigeria for Bio-Ethanol Production

Suitability of four cassava varieties (98/2101, 98/0505, TME 419, and TMS 4(2) 1425) for ethanol production was investigated. The total starch and amylose contents of variety 98/2101 were higher than those of the other three varieties. Variety 98/2101 also gave the highest ethanol productivity and yield. This was followed by variety 98/0505 while TMS 4(2) 1425 gave very low ethanol concentration and yield. The final ethanol concentration and yield were influenced by the age of variety 98/2101. The optimum age for harvesting this variety for ethanol production is 12 months. Above 12 months, some of the tubers started rotting and even ethanol yield per cassava flour decreased. On the whole, the starch contents of the varieties investigated were lower than the values reported for other varieties in other parts of the world. Efforts should therefore be made to develop cassava varieties with higher starch contents in Nigeria.Keywords: Cassava varieties, Fuel ethanol, Koji, Amylase enzymes, Bio-fuel

Microalgal pigments: A source of natural food colors

Naturally sourced colorants and dyes are currently gaining demand over synthetic alternatives due to an increase in consumer awareness brought forward by health and environmental issues. Microalgae are unicellular organisms which are microscopic in size and represent major photosynthesizers with the ability to efficiently convert available solar energy to chemical energy. Due to their distinct advantages over terrestrial plants such as faster growth rates, ability to grow on non-arable land, and diversity in the production of various natural bioactive compounds (e.g., lipids, proteins, carbohydrate, and pigments), microalgae are currently gaining promise as a sustainable source for the production of natural food-grade colorants. The versatility of microalgae to produce various pigments (e.g., chlorophylls, carotenoids, xanthophylls, and phycobiliproteins) that can be commercially exploited as a source of natural colorant is there to be explored. Various growth factors such as temperature, pH, salinity, and light in terms of both quality and quantity have been shown to significantly impact pigment production. In this chapter, we comprehensively review the characteristics of microalgal pigments and factors that affect pigment production in microalgae while evaluating the overall feasibility of exploiting them as a natural source of food colorants