Cardoso A P, Ernesto M, Cliff J, Egan S V, Bradbury J H
Ministerio da Saude, Laboratorio Nacional de Higiene de Alimentos e Aguas, Maputo, Mozambique.
Int J Food Sci Nutr. 1998 Mar;49(2):93-9. doi: 10.3109/09637489809089388.
The cyanogenic potential (ppm HCN equivalents) of 80 samples of cassava flour (obtained from the Mujocojo and Terrene-A areas of Nampula Province and the markets of Nampula City in Mozambique) were determined using a new simple kit, based on the use of picric acid paper (Egan et al., 1997). The kit is compact, requires only a small amount of water and is very simple to use in the field. Comparison with the results of a semi-quantitative method shows a mean deviation between the two methods of 20% (SD 12%). All samples fitted a single population distribution with a mean value of 45 ppm HCN equivalents (SD 37). Two maxima were observed in the distribution curve at 11-20 and 41-50 ppm. Five samples exceeded 100 ppm with two values of 200 ppm. The WHO safe level for cyanogens in cassava flour is 10 ppm. The lowest levels (2 and 6 ppm) were obtained from cassava flour prepared from sweet cassava. Over 76 samples the mean value of the cyanogenic potential of cassava flour produced by heap fermentation is only one half as large as that produced by sun-drying (P < 0.005). Interventions needed to reduce cyanogen levels are (1) improvements in processing methods, such as replacement of sun-drying by heap fermentation, (2) introduction of additional vegetables, pulses and fruit to alleviate the monotonous cassava diet of the people and (3) introduction of high-yielding, disease-resistant, low-cyanide cultivars.
使用一种基于苦味酸试纸的新型简易试剂盒（Egan等人，1997年），测定了80份木薯粉样本（取自莫桑比克楠普拉省的穆乔科霍和泰伦内 - A地区以及楠普拉市的市场）的生氰潜力（以ppm HCN当量计）。该试剂盒体积小巧，仅需少量水，在野外使用非常简便。与一种半定量方法的结果比较显示，两种方法之间的平均偏差为20%（标准差12%）。所有样本符合单一总体分布，平均值为45 ppm HCN当量（标准差37）。在分布曲线上观察到两个峰值，分别在11 - 20 ppm和41 - 50 ppm处。有5个样本超过100 ppm，其中两个值为200 ppm。世界卫生组织规定的木薯粉中氰化物安全水平为10 ppm。最低水平（2 ppm和6 ppm）来自甜木薯制成的木薯粉。在76多个样本中，堆肥发酵生产的木薯粉生氰潜力平均值仅为晒干生产的木薯粉的一半（P < 0.005）。降低氰化物水平所需的干预措施包括：（1）改进加工方法，如用堆肥发酵替代晒干；（2）引入更多蔬菜、豆类和水果，以缓解人们单调的木薯饮食；（3）引入高产、抗病、低氰品种。
