In my kitchen at home I do something I've heard many times you're not supposed to do: I keep a a bottle of olive oil right next to the stove. It's my go-to everyday cooking oil (I like California Olive Ranch Everyday Extra Virgin Olive Oil), and it's just easier if it's always right there at arm's reach. But I do like to do things right, and I've started worrying that maybe I needed to reconsider my system. I've been thinking a lot about how to keep olive oil fresh. So I called up Maia Hirschbein, the oleologist at California Olive Ranch, to find out just how much trouble I was really in, and to get the final word from an expert on how to store olive oil and how to keep olive oil fresh—for as long as possible.
Keep your favorite oil safe from the big bad three—oxygen, light, and heat—with one of these elegant bottles.
Hirschbein was glad to hear I wanted to talk about the subject, because no matter how good your olive oil is, she says, it's how you store it once you get home that really makes the difference when it comes to preserving its flavor and quality. Here's what she suggests:
1. Use That Bottle Up Within a Month
Light, air, and heat all contribute to the degradation of olive oil, she notes, particularly oxygen. The moment you open a bottle of olive oil (just like a bottle of wine), oxygen starts flooding it, and the degradation process begins. That's why Hirschbein suggests using up a bottle of olive oil within a month or two of opening it. How quickly the oil goes rancid depends on many factors, however, including where and how you store it and the temperature of your kitchen. (To track the oil's quality over time, Hirschbein suggests smelling the olive oil right when you open it and before every subsequent use—just like you'd sniff that open bottle of milk before using it to make sure it's still fresh. You'll know when your olive oil is going rancid when you notice that it "starts to take on a more crayon or Band-Aid smell.")
Hirschbein assured me that if you're plowing through olive oil quickly in your kitchen, storing it next to the stove is not the worst thing you can do—in fact she also keeps her everyday cooking oil right by her stove, in a ceramic cruet with a pour spout. (More on that below.) But she stores her specialty extra virgin olive oils, which she uses to finish a dish, in a dark cupboard away from the stove.
2. Store Olive Oil in the Right Containers
Hirschbein uses a ceramic cruet (which of course I've now ordered for myself). A ceramic cruet is especially good for storing olive oil because it not only blocks out light and air, but the thick ceramic walls help block out heat too. If you're going to use a cruet, though, you have to wash it throughly before you refill it each time. Otherwise you'll be mixing older oil in with your fresh oil, which will of course affect the oil's taste.
I really love having a pour spout on my bottle of olive oil—it just makes swirling it into a skillet so much easier—but I was worried it might let too much air in. Fortunately Hirschbein says that the amount of air that gets in through the small opening of the pour spout is not any worse than the amount of air that gets in every time you open your bottle of olive oil. You can get one of the spouts that has a cap on top for even more air protection, though the ones with the little metal flap over the top are not really air-tight. For more on our favorite olive oil cruets, read here.
3. If You Must Buy in Bulk, Go for a Bag-In-Box Option
Extra virgin olive oil can be expensive, and it can be tempting to buy it in the largest container possible to save money. But the bigger the container, the more time the oil is going to be exposed to oxygen, heat, and light before you finish it all up. That's why, if you want to buy olive oil in bulk, Hirschbein suggests buying a bag-in-box container, which helps eliminate oxygen exposure.
You've probably seen this kind of packaging for for boxed wine, but it's relatively new for olive oil. Keep your eyes open for it though—some stores do carry it, and you can also order it online. If you store that bag-in-box in a cool, dark place, and decant the oil into a ceramic cruet (that you've cleaned throughly before refilling), you'll be following all the best practices for how to store olive oil. (Just make sure you know you're actually going to go through that whole bag-in-box within a couple months before you make the investment.)
Originally Appeared on Epicurious