Drying is the most important stage of walnut processing in walnut orchards and private farms. In private or industrial gardens that have just begun to bear fruit and give only a couple of bags, drying is carried out in the open air or in a well-ventilated room. For large volumes, this method is not suitable, since industrial gardens yield tens and thousands of tons.
Problems of walnut drying:
The first problem is the drying of the walnut with the remains of the green fruit. It does not affect the drying process, but directly affects the quality of the walnut, the processing and the cost of the walnut. The pericarp dried on the walnut turns the shell and kernel dark, prevents cracking of the walnut and significantly reduces the value of the walnut and kernel.
Always clean the walnut from the pericarp and its remains. So you will get a quality walnut and earn more.
The second problem concerns large volumes of walnuts (from a ton or more). Natural walnut drying requires a large area – outdoors and indoors. For drying, walnuts are spread in a thin layer on nets, tarpaulins or pallets. Since the weather outside is unstable, the nut must be cleaned at night in a dry room. In addition to space, of course, drying requires human labor, namely staff who will monitor the weather, turn the nut for even drying, bring it indoors and bring it back outside. The larger the volume of the nut, the more space and personnel will be required.
For drying industrial volumes of walnuts, a dryer or drying complexes are required. This is equipment on which neither garden owners nor those who buy fresh walnuts from the public can save money.
Insufficient or uneven drying increases the risk of mold formation. Mold can appear within a month after drying, and later. Nuts with mold will not be bought, and therefore the owner will receive losses.
A hygrometer is used to check the humidity of a walnut; the moisture content of the walnut in the shell should exceed 10%. Unfortunately, it is impossible to check the uniformity of drying, and one can only hope for a responsible attitude of the staff to their work and good conditions for drying.
Dryers have a walnut stirring system and temperature control, which ensures high-quality walnut drying.
There are situations when, after drying, the walnut turned out to be overdried. Such situations are extremely unpleasant, because an overdried walnut loses its weight and elasticity, and in the process of processing it begins to crumble badly. It is impossible to increase the humidity of walnut on an industrial scale. Therefore, always monitor the drying process and use moisture meters to prevent excessive moisture loss.