A Review of Cyanogenic Glycosides in Edible Plants

Cyanogenic glycosides are natural plant toxins that are present in several plants, most of which are consumed by humans. Cyanide is formed following the hydrolysis of cyanogenic glycosides that occur during crushing of the edible plant material either during consumption or during processing of the food crop. Exposure to cyanide from unintentional or intentional consumption of cyanogenic glycosides may lead to acute intoxications, characterized by growth retardation and neurological symptoms resulting from tissue damage in the central nervous system (CNS). Processing methods can detoxify cyanogenic glycosides and reduce the risk of cyanide poisoning. The efficiency of cyanide removal, however, depends on the processing technique employed and the extent of processing. Processing operations such as fermentation, boiling/cooking, and drying, applied to process food‐containing cyanogenic glycosides have been reported to reduce cyanide content to acceptably safe levels. The present review discusses the level of cyanogenic glycosides in specific plant foods, health implications of consuming cyanogenic plants and effect of various processing method on cyanogenic glycosides with updated information gathered from the published reports on cyanogenic glycosides

The implementation of a dualistic model for scale up of a tunnel drying of cassava chips

Tunnel dryer is a combination of two or more cabinet dryers arranged in a serial order in a tunnel. It has found application in drying of both food and non-food origin but its scale up process has hitherto been based on experimentation and experience without comprehensive scientific background which often leads to the poor performance of those dryers. In this study, theoretical modelling for tunnel drying which could effectively predict the dryer’s performance was developed. The modeling process involved the segmentation of drying parameters into an equipment and material models. Equipment model entails the parameters supplied by the dryer such as air temperature, velocity, humidity profiles and heat transfer to the samples being dried (cassava chips). Material model embraces properties of cassava chips such as drying kinetics and drying equilibrium moisture conditions of the sample.The results of the scale up values are 4860 kg/cycle, 600kW, 111 kW, 6.075 m3, 150 oC and 12 for dryer batch capacity, heater’s wattage, fan’s wattage, dryer’s volume, allowable temperature and number of trucks respectively. The study identified and itemized critical model parameters necessary for effective scale-up of tunnel drying. More so, the effectiveness of the dualistic model for tunnel drying of cassava chips has been demonstrated and methods are outlined for using the model to scale up from bench scale test through pilot plant testing to full scale dryer operation. Incorrect application of these parameters would impede successful scale-up of this dryer