The short answer
Keep walnut kernels in a cool, dry and dark place. Once the pack is open, seal them airtight and store them in the refrigerator.
Why proper storage matters
Walnut kernels are sensitive to heat, light, air and moisture. Exposure can make them lose their clean flavour more quickly. Good storage begins with the right place and continues with careful sealing after opening.
Keep away from light and heat
Choose a cool, dry and dark place. Heat and strong light shorten the time in which the kernel keeps its best quality.
Use an airtight container
After opening the pack, place the kernels in a clean container that closes well to reduce exposure to air and moisture.
Refrigerate after opening
Refrigeration is the safest everyday option for opened walnut kernels, especially in a warm room or when they will not be eaten soon.
Protect from strong odours
Walnuts can absorb odours from other foods. A properly closed container protects them inside the refrigerator as well.
What to do after opening the pack
Press excess air out of a resealable pack or transfer the kernels to a container that closes well. Keep the container clean and dry, and use a dry utensil whenever you take out a portion.
If you have several grades, such as whole halves, quarters or walnut pieces, keep them in separate containers.
A tight seal, a low temperature and protection from moisture and odours are the simple foundation of good storage.
What to check before eating
Look at the kernels and smell them. A strong rancid odour, unusually bitter taste, moisture or visible deterioration means the product should not be eaten. When in doubt, choose safety.
Frequently asked questions
Where should I store an unopened pack of walnut kernels?
In a cool, dry and dark place, away from heat sources, moisture and strong odours.
What should I do after opening the pack?
Seal the kernels in an airtight container and keep them in the refrigerator, particularly if they will not be eaten soon.
Can I keep them in the original packaging?
Yes, provided the pack can be resealed properly and is not damaged. Otherwise use a clean airtight container.
How can I tell if walnut kernels have spoiled?
A strong rancid smell, unusually bitter taste, moisture or visible deterioration are reasons not to eat the product.