Cashew nut trees, even though originally native to Brazil, have spread all over the tropical world and today, the significant producers of cashew include Nigeria, India, Vietnam and the Ivory Coast. The key differentiator about the cashew nut is the fact that the nut appears beyond the fruit. The cashew fruit can also be called as cashew apple and the nut appears beyond the fruit. The cashew nut is the seed and this is surrounded by a double shell. In order to finally reach the seed, that’s the cashew nut, these shells have to be removed and this entails systematic processing.
Initially, the raw nuts are cleaned and dirt, sand, rocks and some other particles and foreign matter are removed.
After cleansing, the nuts are dried in the open sun, in order to get rid of the moisture. To be able to make certain that the nuts are dried on both the sides, they have to be rolled over on a regular basis. The drying process occurs under sunlight, usually in an open lawn.
The outer shell of the cashew is extremely hard and should be softened. This is done by way of the roasting process. Here, the cashews are roasted at a stove, which is supplied with steam from a boiler. The roasting time depends on the nature of the cashew and is judged based on experience.
Once the outer shell is softened, it’s cut. The cutting process can be manual in addition to automatic. In the event of automatic operation, there are special machines which do the job. However, the blade setting is highly critical, to make sure that inner kernel isn’t affected. The manual method involves the use of either leg or hand operated machines. There’s a greater control in this process and a greater proportion of kernels come out undamaged. However, great care has to be taken, because the shell contains an allergic resin. This can be harmful, if not properly handled.
Drying in a hot chamber
Even though the outer shell of the cashew has been cut, there is an adhering seed coat or testa. This has to be removed. Since this seed coat is closely held on to the seed, the only way to remove this will be by drying in a hot chamber. Usually, the cashews are held in trays and hot air from a blower is passed over them. The temperature maintained is usually about 75 to 80 degrees Celsius. When the testa is softened, further processing is simple.
In this phase, the testa is peeled. Although in the past, the manual method of peeling was utilized, this has now been mechanized. The most commonly used method is to blow off the testa away by way of high pressure air. This will guarantee testa removal with no damage to the kernels.
Grading and Packing
Finally, the kernels are rated. The broken pieces are separately sorted and the whole kernels also sorted based on their shape, color and other parameters. Packing of different grades is done in a hygienic environment and the cashews are prepared to hit the market for consumption.