Walnut processing: stages and equipment
Walnut processing is considered as one of the most labor-intensive stages in the walnut business. Walnut processing consists of some cycles, combined into one large technological process. This process consists of the following main stages: harvesting, picking, washing and cleaning of the green pericarp, drying, calibration, cracking the walnut, aspirating, sorting the kernels, inspecting the color of the kernel.
In order to better understand how walnut processing is going on, it is important to study in detail each stage and what equipment is used on each of it.
Zbiory
The first stage of processing is called harvesting. In households, it occurs either manually, or the owners wait until the nut naturally falls from the trees and can be collected. To save time, special machines — shakers — are used in factories. They quickly shake the walnut from the tree. Shakers can be hydraulic and mechanical, and they can remove walnuts from trees in a minute of work.
Walnut picking
As a rule, walnuts are harvested manually or with the help of special equipment – walnut picker. At large enterprises, the collection is carried out by special machines. This process is very fast.
Walnut washing and cleaning off a green pericarp
Washing and getting rid of the green pericarp – is the next step in the processing of walnuts. This step is necessary, so that the walnut kernel does not turn black, does not dry out and the shell is not covered with mold. Walnuts are washing up in special rotary washers. Rotary washer do it very quickly and efficiently. At home, walnuts are washed manually or using household walnut cleaners from green pericarp. The principle of such a cleaner is simple: the nut is loaded into a special drum, in the drum it is separated from the green peel, washed with water and can be sent for drying.
Walnut drying
Drying is necessary so that the walnut does not become moldy and damp. On a large production scale drying is carried out using special equipment. If the walnut is poorly dry, it can be dried in well-ventilated and warm warehouses. At home it is dried in warmth or in the fresh air under the canopy.
Walnut calibration
At the calibration stage, the walnut is sorted into fractions for high-quality cracking by industrial nutcrackers, in order to increase the integrity of the kernel. In big productions, dried walnuts are calibrated on rotary calibrators, the productivity of which can reach up to 500 kg/h. At home, walnuts can be calibrated with a help of household calibrators with a productivity of 50 to 200 kg/h or manually.
Walnut cracking
Cracking – is the process of separating the shell from the kernel. On a production scale, walnuts are cracked with industrial nutcrackers, the productivity of which reaches up to 200 kg/h and after the rut the integrity of the kernels is maintained at the maximum level. At home, walnut cracking is carried out manually or with a help of mechanical or electric nutcrackers.
Aspiration
Aspiration is a process of the dust and small particles removal from walnut kernels. It is carried out on special aspiration tables. Aspiration occurs mainly on a production scale.
Sorting kernels by fractions
The next step is sorting the kernel into a fractions. Here, the kernels are sorted by standards and this allows entrepreneurs or households to increase the walnuts price on the market. Calibrated by the fractions equally used in large-scale production, medium-sized industries and also at home. This process requires a lot of time and great care while doing at home.
Core color inspection
The final step in walnut processing is to re-check the color of the kernels. This is mainly used when walnuts preparing for sale.
From the point of view of time and labor costs, the entire walnut processing may seem lengthy and complicated, but in fact it runs very quickly on a production scale and can slow down if you do everything manually at home.