Steps to Process a Cashew Nut
Cashew nut trees, even though originally native to Brazil, have spread all over the tropical world and now, the major manufacturers of cashew include Nigeria, India, Vietnam and the Ivory Coast. The key differentiator concerning the cashew nut is the fact that the nut appears beyond the fruit. The cashew fruit can also be known as as cashew apple and the nut seems outside the fruit. In order to finally get to the seed, which is the cashew nut, these shells have to be eliminated and this entails systematic processing.
The steps involved are
At first, the raw nuts are cleaned and dirt, sand, stones 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 need to be rolled over on a regular basis. The drying process happens under sunlight, usually in an open yard.
The outer shell of the cashew is very hard and should be softened. This is done by means of the roasting process. Here, the cashews are roasted in a cooker, which is supplied with steam from a boiler. The roasting time depends on the nature of the cashew and is judged based on experience.
When the outer shell is softened, it is cut. The cutting process can be manual as well as automatic. In the event of automatic operation, there are special machines that do the job. But the blade setting is extremely critical, to ensure that inner kernel is not affected. The manual method involves the use of either hand or leg operated machines. There’s a greater control in this process and a higher 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. Because this seed coat is tightly held on to the seed, the only way to eliminate 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. Once the testa is softened, further processing is simple.
In this phase, the testa is peeled. Although previously, the manual method of peeling was used, this has now been mechanized. The most commonly used method is to blow the testa away by way of high pressure air. This will guarantee testa removal with no damage to the kernels. Other methods employed include freezing, suction, passing the kernels via rubber rollers, etc..
Grading and Packing
Lastly, the kernels are rated. The broken pieces are sorted and the entire kernels also sorted according to their shape, color and other parameters. Packing of different grades is done in a hygienic environment and the cashews are ready to hit the market for consumption.