To store and enjoy walnuts for as long as possible, it’s important to dry them properly before moving them into storage. Here you can find out the best way to dry them and what to look out for.
From mid-September to the end of October, ripe walnuts fall from the tree on their own, landing on the ground and detaching themselves from their shells. During this time, it is important to regularly go to pick up the nuts from the damp grass as quickly as possible. Otherwise, the increased moisture in the fall can quickly lead to mold. Before the gathered walnuts can go into the pantry or storage, you must first dry them. Only then can the tasty nuts be stored for about a year without losing flavor or quality.
How to treat freshly harvested walnuts?
The collected walnuts should first be freed from the remnants of the outer shell. If the nuts are left in a protected place for a day after harvesting, the shell can be removed more easily. Gloves and old clothes or an apron should be worn when doing this. The walnut shell contains tannic acid, which leaves stubborn stains. It is best to use a coarse brush to clean the nuts. Under no circumstances should you wash the walnuts, as this could allow fungal spores to enter the fruit and cause premature spoilage.
Why do walnuts mold when they dry?
Nut shells absorb moisture from the ground and from the air. It penetrates through small crevices and openings into the interior of the walnut, where mold spores can rapidly form and spread. If the fruit is not properly dried before storage, moisture and mold can ruin the entire crop within a few weeks. It is also important to check the collected nuts for pre-existing mold before drying.
What is the best way to dry walnuts?
For drying, it has proven useful to line fruit crates with several layers of sandwich paper and spread the walnuts out in a single layer. It is important to leave enough space between the nuts so that they get air from all sides. Wooden frames covered with fabric or a grid are also well suited for drying walnuts. If the frames are built appropriately, they can be stacked or hung up to save space, while the air can still circulate well between the nuts.
In the beginning, walnuts should be turned daily, and later every two to three days. Regular and frequent turning prevents mold growth and promotes an even drying process. In addition, rotten fruit can be identified and sorted out. Otherwise, the mold may spread to the rest of the harvest.
Where is the best place to dry walnuts?
It is recommended to dry walnuts indoors, where they are protected from the weather and night humidity. The best place is a uniformly warm, sheltered room with a temperature between 20 and 25 °C / 68 and 77 °F and normal, not too high humidity. The drying temperature should not exceed 28 °C / 82 °F, otherwise the oils contained in the walnut may become rancid and the nuts will no longer taste good.
How long should walnuts be left to dry?
Depending on the weather and moisture content at harvest and on the given room conditions, drying walnuts can take three to six weeks. But time and patience pay off and reward with full flavor and long shelf life. Properly dried and stored, walnuts will keep for a year or more. You can find out whether the drying process is complete by testing them regularly. To do this, open two or three nuts and look at the kernel. If it is pliable and rubbery, the nut is not yet dry enough.
On the other hand, if the shell and walnut kernel are brittle, while the partitions between them rustle, the nuts are ready to be stored and moved to a suitable storage area. It is then best to fill the dry walnuts into nets, burlap bags or potato sacks and hang them in a dark, dry place. In this way, even ventilation can be ensured. At a room temperature of 10 to 18 °C / 50 to 64 °F, walnuts also do well in shallow baskets, wooden stairs or fruit crates.
Can walnuts be dried on the heater or in the oven?
At temperatures above 28 °C / 82 °F, there is a risk of nuts becoming rancid. Therefore, walnuts are best dried and stored in an insulated attic, cellar or pantry. For this reason, the nuts should not be dried over a radiator, in a dehydrator or in an oven. This would be much faster, but the quality and taste would suffer greatly from the excessive heat.