Influence of water pH on cyanide elimination during cassava fermentation harvested in Maluku, Democratic Republic of the Congo
DOI:
https://doi.org/10.59228/rcst.026.v5.i2.279Keywords:
Cassava, pH, cyanide, cyanide removal, fermentationAbstract
This study analyzes the influence of pH on the detoxification of cassava (Manihot esculenta Crantz) during retting, a vital process for food security in the Democratic Republic of Congo. The objective is to evaluate the impact of reusing fermentation water on the elimination of cyanogenic glycosides, a common practice in water-stressed areas such as the Batéké Plateau. Twelve varieties (7 improved and 5 local) were subjected to comparative trials at the University of Kinshasa. The results obtained illustrate that while water reuse can accelerate root retting (reducing it to less than 48 hours), it leads to acidification of the environment. The increase in lactic acid bacteria lowers the pH to a dangerous level of 3.3. The excessive acidity of the medium inhibits the activity of linamarase (β-glucosidase), which is responsible for the hydrolysis of cyanogenic glycosides. During the third retting process in the same water, the residual cyanide levels in the cassava remain alarmingly high. This study highlights the rapid softening of roots achieved through water reuse, which contradicts the sanitary requirement for detoxification. Ultimately, pH management is the crucial parameter for the safety of the final product and to guarantee consumer health; it is imperative to adjust the pH before any further use.
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