Are Pickles Cucumbers? Here's What You Need to Know About the Pickling Process

Fresh cucumbers have a mild, refreshing taste, but once you ferment them, you end up with something different entirely: a salty, sour pickle. It's amazing to think that these two foods are related, and if you're interested in learning more about the process that turns cucumbers into pickles then you've come to the right place.

How Do Cucumbers Become Pickles?

The main process at work here is fermentation. Cucumbers are submerged in a saltwater brine or vinegar; with time (anywhere from several days to even months), those cucumbers will turn into pickles. "Cucumbers ferment in a fairly straightforward process that begins with bacteria of the lactic acid bacteria family," David Ehreth, founder and president of Sonoma Brinery in Healdsburg, California, explains. "These are bacteria that do not cause harm to humans and whose metabolic process is to harvest sugars from cucumbers and convert those sugars into energy for the bacteria and lactic acid as a byproduct." This bacteria naturally lives on the skins of cucumbers.

The saltwater brine provides an environment in which lactic acid bacteria grows and unwanted bacteria does not. Ehreth adds that the salt also draws out fluids from the cucumber that offer nutrients to the bacteria. This gives pickles their salty taste and crisp texture. The lactic acid bacteria turns the sugars from the cucumber into lactic acid, which gives cucumbers their funky, sour flavor. A standard brine is made up of 95 percent water and five percent salt. Depending on the brine or vinegar you're using and how flavorful you want your pickles to be, the fermentation process can take a few days to several months.

Lacto-Fermented Versus Vinegar-Pickled Cucumbers

When cucumbers are placed in a saltwater brine, they undergo lacto-fermentation and develop a funky, sour flavor. Vinegar-pickled cucumbers, on the other hand, rely on the acidity of the vinegar to give the cucumbers that sour tartness, Jennifer Sargent, associate development chef for Vlasic pickles, explains. "In terms of flavor, the lacto-fermented pickles will have a bold and much saltier flavor profile," she says. "Vinegar-pickled cucumbers will have a stronger acidity and sourness." Vlasic pickles are vinegar-pickled and heat treated so that they can be safely stored at room temperature.

Jordan Harvey, executive chef of Hearth and Hill in Park City, Utah, describes lacto-fermented pickles as a living, breathing thing. "Flavored with fresh garlic, peppercorns, and dill, these pickles pack more of a crisp bite to them with fresh flavors standing out more versus the vinegar-pickled kind where flavors are heightened through the added acidity." While it can take a month for vinegar to flavor cucumbers, Harvey notes that pickles can be left in a saltwater brine for a few days or weeks depending on temperature, humidity, and flavor preference.

What Types of Cucumbers Are Best for Making Pickles?

All three of our experts agree that kirby cucumbers are best for pickling because of their thinner skin, which allows the pickling solution to penetrate. "Nearly all commercial pickles are made from cucumbers referred to, not surprisingly, as 'pickling cucumbers,'" Ehreth says. Pickling cucumbers are not too big (so they can fit in a jar or container), have bumpy, relatively thin skin, plus a small seed cavity and fairly thick flesh.

If you're buying cucumbers to pickle, ensure that they are firm, unblemished, and that the skin isn't shriveled (which indicates they're past their prime). Fresh is best. "If you can't grow them yourself, a local farmers' market will yield fresher produce," Sargent says. She recommends storing cucumbers in the refrigerator until you're ready to process them, ideally within 24 hours of harvesting. Before submerging them in the pickling liquid, she recommends washing the cucumbers in plenty of cold water to remove any residual soil which can harbor unwanted bacteria.

What Are Half-Sour Pickles?

A half-sour pickle is exactly what it sounds like: a pickle that is fermented on the outside and still resembles a cucumber on the inside. "I think of the half-sour as the king of pickles due to the beautiful balance of fresh cucumber flavor and texture with the tart and salty character of a pickle," Ehreth says. "Neither overwhelming nor lacking for tartness, full of palate-lifting cucumber flavor yet seasoned with a perfect spice and garlic bouquet."

If you're making pickles at home, Ehreth says that you can tell they are half-sour when the cucumber skin changes from bright green to olive green. "Take a pickle out of the ferment at about day four (or just when the color of the skin changes), cut it from one end to the other into spears, and you should see that the area around the skin is darkened and somewhat translucent while the interior still appears like a fresh-cut cucumber," he says. If you're happy with how your half-sour pickle tastes, put the rest of the pickles in the refrigerator to slow down the fermentation. The longer you wait to eat them, the more sour they will taste; in a few weeks you will have full-sour pickles. "You can make a whole-sour out of a half-sour, but you can't make a half-sour out of a whole-sour. Don't wait," Ehreth says.