CASHEW NUT PROCESSING OVERVIEW
HARVEST, POST HARVEST, HANDLING & STORAGE OF RAW CASHEWNUTS.
The cashew apple and not abscise from trees naturally when ripe.
Maturation occurs over a period of several weeks during the dry season.
Nuts are collected from the ground by hand.
Frequent passes though the planting must be made if apples are to be utilized,
as they are highly perishable. Rain at harvest may increase rot and stimulate not germination.
POST HARVEST HANDLING
The presence of caustin cashew nut shell liquid ( CNSL)
in the shels makes cashew processing little difficult and hazardous.
Nuts are dried in the Sun on the hard ground i.e. on concrete yards.
The nuts should be spread on the hard ground.
For proper drying of nuts constant turning is important.
Nuts require two / three days of Sun drying.
Dried nuts should be stored in Jute bags and kept above the floor on wooden dunn.
Direct contact of nut bags and floor should not be there, as this may damage the cashew nuts.
The warehouse should be well ventilated with low humidity.
PROCESSING OF RAW CASHEW NUTS
1) Steam Cooking
3) Drying of Kernels
Steam is developed in the boiler up to 100 / 125 psi and released in the cashew cooker for about 25 to 30 minutes.
This expands the shell and softens the nuts due to penetration of the steam in the shell.
After steaming process the nuts are spread out on the floor. After few minutes the nuts again gets hard.
The nuts are de-shelled by hand, and leg operated cutters. The nut is kept between two sets of
blades to fit the contour of the blade. By pressing the pedal the two blades pierces the cashew
nut. Simultaneously the handle of the cutter is moved up to splits the nut. After de-shelling the
kernels are seperated from the shell and goes for drying.
DRYING OF UNPEELED KERNELS
The Kernels are dried in the tray dryers to remove the tanning and moister content inside the
Kernel. Drying also helps in easy peeling of Red / Brown skin.
The Kernals should be dried at 700C for 6 / 7 hours.
PEELING OF DRIED CASHEW KERNELS
The process of removing red / brown skin ( Testa ) present on the Kernel by hand or by
automatic machine is called PEELING
GRADATION OF CASHEW KERNELS
The peeled cashew Kernels are graded on the basis of size, shape and colour.
FILLING AND PACKING
Before packing, the graded kernels should be dried again for 1 hour at 700C, so as to remove the little amount of moisture gain during peeling.
and grading process.
The kernels are filled in tins with the help of vibratory filling machine.
The filled tins are vacuumized and gas is infused (CO2 / Nitrogen) with Vita packing machine.
The gas infused tins are hand-soldered using lead free solder.
Cashew kernels can also be packed in flexible pouches.