Efeito do congelamento de raízes de mandioca (manihot esculenta crantz) na conservação e no conteúdo de cianetos

Abstract

The consumption of fresh cassava roots is strongly affected by its short shelf life post-harvest conservation and the presence of cyanogenic glycosides (CNp), compounds toxic to humans and animals. In order to increase shelf life and reduce the CNp content, fresh cassava roots were frozen at -20 oC for a period of one month. During freezing, parameters such as pH, color, cooking time and cyanide content. Two varieties were used, one being described as sweet variety (Munhaça) and the other as bitter variety (Nkussi). After one month of freezing, there were no significant changes in pH and color of frozen cassava roots. The cooking time was significantly reduced by 30%, with a week of freezing, showing the influence of the freezing of the roots in the rapid reduction of its cooking time. One month of freezing of cassava roots resulted in a significant decrease in the cyanide content in frozen and cooked cassava roots, where the sweet variety decreased from 36.12 to 5.15 mg HCN / Kg and the bitter variety from 1011.63 to 102.7 mg of HCN / Kg on dry basis, respectively. From this work, it can be concluded that the freezing of cassava roots can be an alternative for conserving and reducing the cyanide content of cassava. (TRADUÇÃO NOSSA)