Abstract
Cassava is a shrub belonging to euphorbiaceous family, widely cultivated in South America, Africa and the Pacific because of its roots with starches of high nutritional value. There is a variety called Manihot utilissima or bitter cassava, which contains high concentrations of cyanogenic elements that make it unusable and poisonous raw material which avoided for human consumption, while the high concentrations of carbohydrates place it as a potential source of starch mainly for industrial use. The wet extraction method was used to get starch from bitter cassava (Manihot utilissima). A factorial (2x3) design was implemented for the experimental set up, with 2 levels of time and mincer speed and 2 for the temperature of H2O, with 2 independent replicates. The comparison with the dry extraction method was also studied, this method consists in drying the bitter cassava over night at 50°C. The yield of starch obtained in wet method ranged from 17.2 to 39.4 g of starch (mean of 26.6 g) obtained from the original samples of 250 g of wet bitter cassava, yielding yields ranging from 6.88 to 15.76% (average 10.64%) of the dry mass. The results were then analysed using PAST software v3.16 for ANOVA statistical evaluation, trend and Pareto were used to determine optimal conditions for the extraction of starch by wet and dry methods. Once the assumptions for analysis of variance (ANOVA) were made, it was concluded that a higher yield of starch is obtained from lower speeds and time, whereas the temperature of H2O is not significant for the process, giving as optimal value for wet method = 0.0678762 for 1/x of the yield of starch obtained, with a starch purity of 64.90% ± 1.21% ranging up to 85.37% ± 1.42%. The extraction of bitter cassava starch has demonstrated its potential for the use of this variety of cassava which generates an added value to the product.
