Analysis of modes of heat transfer in baking Indian rice pan cake (Dosa,) a breakfast food

Heat transfer by individual modes is estimated
during baking of rice (Oryza sativa) pan cake (Dosa), a
traditional food. The mathematical expressions proposed
could be used to modify the baking oven for controlling the
individual modes of heat transfer to obtain the desired
product texture, colour and flavour. Conduction from the
rotating hot plate is found to be the most prominent mode
of heat transfer and is critical for obtaining the desired
product characteristics such as texture and flavour. Temperature
profiles along the thickness of Dosa are obtained
and compared with those obtained experimentally. Heat
transfer parameters such as thermal conductivity and
emissivity of Dosa are determined (0.42 W/m K and 0.31,
respectively). The effect of material of construction of the
hot plate such as alloy steel, teflon coated aluminum, cast
iron and stainless steel on product texture was studied and
stainless steel was found to give good surface finish to the
product, which was confirmed by scanning electron
microscope. Sensory evaluation was carried out to evaluate
the product acceptability. The thermal efficiency of the
baking oven was 51.5%.