How do pickles and olives keep after opening?

In an opened jar of turşu (Turkish pickles) or olives, what decides things is not the time that has passed but whether the product stays under its own brine and what goes into the jar. Both of these conditions can be watched by eye; that is why what is described here is what to look at rather than a number of days. How a jar is used makes far more difference than the date it was opened.

What does the brine do?

Brine is not only the liquid the product sits in; it is what defines the environment around the product. With its salt and its acidity, it sets the conditions inside the jar.

A piece left above the liquid stays outside that environment. A surface in contact with air behaves differently; usually that is where the color changes, where it softens or dries first. The first spoiling in a jar usually shows on a single piece at the top.

As the level drops, that part left outside grows. So the real issue in a jar is whether the dwindling product still sits under the liquid.

Why does the fork that goes into the jar matter?

Every time you reach into the jar, whatever is on what you reach with is left in the liquid. Taking pieces by hand, or dipping in a fork that has been eaten from, adds everything from outside into the environment of the jar.

So only a clean, dry fork or spoon goes into the jar. If you take from the same jar several times a day, keeping that utensil separate makes it easier to do.

Wiping the lid and the rim of the jar is part of the same job. A crumb left on the rim sits between the threads of the lid and comes back every time the lid is opened. Not leaving the jar open on the table for a long time makes a difference too, for both temperature and contact.

What do you do when the level drops?

Pushing what is left down under the liquid is the first and simplest step. If the product has run low, moving it into a smaller jar does the same job; in a small jar the liquid is enough to cover what remains and the air above it is reduced.

The most common thing people do is pour the liquid away. Yet the brine is what carries the product; when it is poured off, what remains is a product left dry. Topping it up with water thins that environment too, because the salt and acid levels are what make up the environment itself.

Making sure the lid closes fully is the last step. If the label carries a storage instruction for after opening, that instruction is what counts; the suggestions here do not take its place.

What do you look at to decide?

The signs to watch for are in the jar itself: the liquid clouding, a layer forming on the surface, a clear change in smell, the product softening more than it should, the lid bulging, or unexpected pressure when you open it.

If one of these signs is there, the jar is not eaten from, and the decision is not made by tasting. Picking out part of it and using the rest is not a suitable method for this item either; because the liquid is shared, the visible part cannot be judged on its own.

No number of days is given here, and that is deliberate. The salt level of the product, its acidity, whether it is homemade and how the jar is used all set the time together; a single number meets none of these conditions. The only thing that can be measured is your own jar: the level, the clarity and the smell.

What can you do today?

You can take the open jars out of the fridge and look at their levels; pushing the pieces left on top down under the liquid is a job of a few seconds.

Setting aside a separate fork for the jar is a one-time arrangement too. Keeping that fork next to the jar lets the habit remind you of itself.

You can try moving the product into a smaller jar when it runs low. This both lets the liquid cover what is left and frees up space in the fridge.