Study on Solar Drying of Fenugreek Leaves

Popularly known in the Indian subcontinent as Kasuri Methi, fenugreek (Trigonella foenum-graecum) leaves are an ancient spice used in various curries, subzis and parathas. The leaves have a bitter taste, but when added after dried, their distinctive taste fascinates the taste buds. Apart from being used as a condiment, it is also added while preparing starchy vegetables, thick gravies and raitas for flavour. Fenugreek contains a very high amount of Protein (4.4 g/100 g). However, these Protein compounds are highly volatile and susceptible to heat and solar radiation. There is a great loss of biochemical constitutions of fenugreek dried with sun drying as compared to mechanical drying. It is noted that the large drying period for which the product is exposed to the atmospheric oxygen has an effect on the reduction in quality aspects. Therefore, controlled drying by forced convection will provide a better-dehydrated product of fenugreek. In the present investigation, efforts have been made to study the drying characteristics of fenugreek and to compare the natural convection drying behaviour of fenugreek with open sun drying and shade drying.