When do walnuts go rancid

So why do walnuts go stale more quickly than other nuts? And how can you store them to make them last longer? Read on to find out more. But if you've only started eating walnuts recently you might find our article on Everything You Need To Know About Walnuts a little more useful. To understand why walnuts go rancid so quickly, we first need to know a little more about the process of rancidification itself.

Rancidification happens when fats and oils are exposed to air, light, moisture or bacteria, causing them to oxidize and to change at a molecular level.

When oxidation occurs, fatty acids and oils, like those found in nuts, begin to change into short-chain aldehydes and ketones, which taste unpleasant and smell bad. The reason why walnuts go rancid so quickly is that they contain a very high level of fatty acids, meaning that they are more susceptible to oxidation when stored incorrectly. Other nuts that go rancid very quickly include pistachios and pine nuts, which also have a very high-fat content.

The good news is that the oxidation process can be slowed down by storing nuts correctly. Before worrying about storing walnuts make sure you are buying fresh, good quality walnuts so your chances of a rancid walnut are slim to none! While it is true that walnuts remain fresh and edible for a long time, there does come a point when they no longer taste good. The shelf life of walnuts with a shell is more than for those without a shell.

Unshelled walnuts can last for a whole year, sometimes even more than that. Hence, you can expect quality walnuts to remain fresh for at least 12 months if they are still in their shell. After the best by date on the packet, most walnuts go bad, but some still retain their freshness if stored properly.

As stated before, shelled walnuts go bad faster than unshelled ones. If you keep them in the fridge, they will not turn rancid before six months. The best way to tell whether an unshelled walnut has gone bad is by looking at its shell. However, if you have shelled walnuts, you will need to use some of your senses to figure out if they have gone stale.

You see a layer with dark spots on them. They smell unpleasant. The degrading oil gives them an odor like that of cooking oil. They taste bitter. Walnuts never taste bitter, but stale ones do because of the oil that turns rancid.

If you notice any of these signs, that means your walnuts have gone bad and you need to discard them. How to Store Walnuts Properly? To check rancidity, perform a sniff test. Walnuts should have a fresh nutty aroma, but if they seem to smell more like rancid oil or cooking oil — the walnuts have gone bad.

Some other chief signs include the nutmeat looking much darker than the usual, a paint-like smell, and a bitter flavor. Just like most other nuts, walnuts too are very high in fat content. The key here is to store the nuts properly by keeping them away from certain food-damaging elements, including heat, air and moisture.

You can simply keep them out of direct sunlight to prevent the shell from heating up. Just crack only enough walnuts that you are going to use in the following few days. Speaking of shelled walnuts, they become vulnerable to moisture and oxygen as soon as they are shelled.

Once you open the packaging, transfer the walnuts into an airtight container and put them in the refrigerator. This extends the shelf life of walnuts from weeks to even 2 months. Freezing them can extend their life even further if put in a vacuum food bag or a sealed container.

Frozen walnuts retain their freshness for up to 12 months. In short you should go for unshelled walnuts if you plan to stock them up. Unshelled ones keep a lot better than the shelled nuts, while going for a cold storage works best for both the varieties.