Credit: Mara Weinraub
In 2022, I visited Piro’s olive farm and mill in Italy to watch just-picked olives turn into the oil we use to dress salads, roast veggies, and dip our breads. It was a technological marvel and, as I saw this vibrantly hued, very high-quality extra-virgin olive oil appear before my eyes, I thought about the many bottles of oil back home on supermarket shelves. I wanted to know how to spot a worthy everyday olive oil at the grocery store without having to visit its production facility first.
Credit: Mara Weinraub
As fate would have it, Nancy Ash, president of Strictly Olive Oil and longtime member of the California Olive Oil Council Taste Panel, was there to answer all my questions — and then some. She happily shared her decades of knowledge and lesser-known tips about what to look for when picking up a bottle of olive oil. These are the three most important things she considers before buying any bottle of oil.
Credit: Aliza Gans
1. The packaging should protect the oil.
This is the number-one thing Ash looks for when shopping for oil. She buys olive oil that’s stored in either a tin or dark glass — basically anything that mitigates light and oxygen from getting into the oil. (While we were chatting, she mentioned California Olive Ranch 100% California Extra-Virgin Olive Oil as a quality option to pick up when shopping in the supermarket.) Clear glass doesn’t protect the oil, and although some producers store these olive oils in an opaque box, the bottles, Ash points out, are typically displayed out of the box on store shelves, which means that the oil is degrading before you even open it.
“Anything sold in plastic,” she advises we “walk on by.” (Plastic is porous, explains Ash, which allows for oxygen to pass through the bottle and, once again, degrade the oil.)
Credit: Mara Weinraub
2. It should also have a harvest date.
Not to be confused with the best-by date, which is typically used to indicate peak quality, the harvest date tells you when the olives were picked from the trees. “What the harvest date tells me is that the producer understands what they’re working with,” says Ash. She explains that the harvest date is usually on the back of the bottle, although, as she points out, “It’s not always easy to find.”
“If there isn’t a harvest date on a bottle,” she adds, “there’s a good chance that the producer has put two different years of harvest into that bottle.” That matters because olive oil goes rancid relatively quickly. How quickly? Generally speaking, olive oil is good for 18 months from when it was harvested. So if a bottle contains oil from last year’s harvest, there’s a good chance that it will turn rancid before you’re able to finish it.
Credit: Christine Han
3. You should consider how much and how often you use the oil.
While it’s tempting to buy a sizable tin because it’s a better deal, you might want to reach for a smaller container. As soon as you open the oil, explains Ash, you’re introducing oxygen to the tin, which, as we now know, deteriorates the oil. If you’re someone who uses a large tin’s worth of oil on a regular basis, then go ahead and buy it in bulk. Otherwise, she recommends you buy oil in a quantity that you’ll use up within two to three months.