How to store and freeze olives and pickles.

Before you open it

Olives in a glass jar or a tin have been heated and sealed shut. The heat kills the germs that make food go bad, and the seal keeps new ones out. That is why they can sit on a shelf for a long time.

Keep them somewhere cool and dark, like a kitchen cupboard, not next to the oven or in the sun. Look for the best-before date on the label. It tells you how long they stay at their best.

Olives in big barrels and buckets work a little differently. They are not heated. The salty water they float in, called brine, protects them instead. So the lid must stay shut, and the olives must stay under the brine.

After you open it

Once you open a jar, air and germs can get in. From now on the olives live in the fridge, where the cold slows germs down.

Keep the olives covered by their brine. Brine is like a blanket that protects them. Use a clean spoon to take them out, not your fingers.

If the olives came in a tin, move them and their brine into a glass or plastic box with a lid. Then eat them within the time the label says.

Restaurants and shops with an open bucket or barrel follow the same rules, just bigger. Close the lid every time, keep the olives under the brine, and use the oldest ones first.

What if the brine is gone?

Olives without brine do not last long. They start to dry out in a few hours. Plain water is not a good swap, because it waters down the salt that keeps them safe. If you lose the brine, keep the olives in the fridge and eat them soon.

Some things look strange but are normal. A little oil on top of the brine comes from the olives themselves, because olives are full of oil. A thin white layer is usually harmless yeast. Scoop it off and eat the olives soon if they smell fine.

Can you freeze olives?

Yes, but you usually do not need to, because they already keep well in the fridge. Freezing turns the water inside the olive into tiny bits of ice. The ice breaks the olive a little, so it comes out soft.

Soft olives are still great on pizza, in pasta sauce or in bread. To freeze them, drain off the brine, pat the olives dry and spread them on a tray so they do not stick together. When they are frozen, put them in a bag or box. Let them thaw in the fridge before you cook with them.

Peppers and pickles too

Pickled peppers, gherkins, cucumbers, mushrooms and onions follow the same rules. Closed jars go in the cupboard. Open jars go in the fridge, with the pickles under their liquid.

When to throw them away

Throw olives or pickles away if you see fuzzy mould, if they smell sour or rotten, if the brine has gone slimy or thick, or if the lid or tin is puffed up. A puffed-up lid means germs are making gas inside. Do not taste it. If you are not sure, throw it out.