Selected Ghanaian cassava and sweetpotato cultivars: Evaluation of flour and wort quality

Abstract

Studies were conducted on the suitability of flour samples of three cultivars of cassava (Afisiafi, Gblemoduade, and Tekbankye) and sweetpotato (Sauti, Farah, and TIB2) as brewing adjuncts. Significant varietal differences (p<0.05) were observed in fat content and ash of the flours. In addition, the protein content of sweetpotato flours varied with cultivar. Wort colour and free amino nitrogen (FAN) levels were dependent on the cultivar. Worts from the sweetpotato flours exhibited intense colour (11.34-16.85 EBC) compared with for cassava (6.49-8.49 EBC), suggesting that they may be suitable for the production of distinctive beer types in Ghana. Since Sauti wort was the lightest among the sweetpotato worts, it should be the sweetpotato cultivar of choice for the production of lager beer. There were significant differences (p<0.05) in FAN level, extract content and fermentability of cassava worts. Wort from Afisiafi had the highest extract content suggesting that it might be a suitable brewing adjunct for lager beer. Gblemoduade produced a more alkaline (pH 6.27) wort than all other samples. The rate of filtration of cassava wort samples was unacceptably slow, indicating a high beta glucan content.