Integrated hot air roasting machine

The roasting operation enhances the organoleptic properties and the device comprises of the roasting, resting and cooling operation in a single machine, which are done sequentially. The invention relates to an integrated hot air roasting machine for roasting / toasting of cereals, pulses, spices, oil seeds and ready to-eat snack foods using flue gas. The product processed by using this device has uniform color, moisture and other sensorial properties, and the material is processed under hygienic conditions in a continuous manner. All the variables such as residence time, temperature of the hot air, resting time and cooling time of the roasted material are dine sequentially by use of a programmable logical controller (PLC). The development of the integrated hot air roasting machine would result in reduction in human drudgery, clean and hygienic end product free from sand, ash and will have uniform color and uniform roasting. The device is energy efficient as the hot air is recirculated. The capacity of the integrated roasting machine range from 100 ~ 150 kg / h. The air velocity for fluidization of grains vary from 1.5 ~ 2.4 m / s, at an air temperature ranging between 300 ~ 350°C. The residence time of roasting can be varied from 20-150 seconds according to the input raw material. The roasted material will be discharged through the out let chute of the hot air roasting machine to the resting chamber, where the material is held inside this chamber for the moisture to stabilize. The material is then allowed in to the cooling chamber to cool the material to the room temperature of around 30°C with the final moisture of around 4~5%.