Lemon zest deserves its name. These parings from the outer skin of a lemon are zesty, zippy and zingy, adding a distinctive note to many recipes. But what if you don't have fresh lemons on hand? Can you simply use lemon juice to substitute for lemon zest? And if so, how?
Using Fresh Lemon Juice as a Lemon Zest Replacement
If you have fresh lemons on hand, you can darn well get zest from them, so why even think about using their juice instead of their zest? Well, maybe you have your reasons. Maybe the lemon peel is too thin or too discolored to be usable.
Or, maybe you have only waxed fruit on hand (lemons are often given a waxy finish to make them appear smooth and slick). This coating is supposedly edible, but you probably don't want it in your food. The process of dewaxing lemons involves either softening the wax with heat (in the microwave or with very hot water), cooling the fruit and then scrubbing it with a vegetable brush; or vigorously washing the fruit with a special preparation, either a homemade vinegar-and-water solution or a commercial product.
So, you don't have the time or inclination to zest the lemons you have on hand. That's OK — all you have to do is squeeze the juice out of 'em. Some cooks recommend using 2‒3 tablespoons of fresh juice for every tablespoon of zest called for in your recipe; others recommend replacing a teaspoon of zest with 2 tablespoons of juice. This is obviously not an exact science. It's best to add a little juice at a time until you achieve the level of flavor you want.
Also, keep in mind that using liquid instead of zest, unless the quantity is extremely small, will change the nature of the mixture. You may need to reduce the amount of other liquid elements.
Be Prepared: Freezing Fresh Lemon Juice
A long-term solution would be to always have fresh juice available (a good idea whether or not you'll be using it as a zest substitute). This is fairly easy to accomplish, and you'll only need to visit the supermarket once.
Buy a bag of lemons. When you get them home, squeeze out their juices. If you have a juicer, all the better. Make sure all the seeds are removed. Pour into an ice cube tray, measuring 2‒3 tablespoons of juice per compartment. After the juice has frozen, remove the cubes, place in tightly sealed freezer bag and store in the freezer for up to six months.
Using Bottled, Canned or Otherwise Packaged Juice
Packaged lemon juice usually doesn't taste much like lemon zest. It tends to be lemon-sour instead of lemon-bright. Additives and preservatives in packaged juice tend to give it a chemical aftertaste, as well. Still, it has the advantage of longevity; after it's opened, it can be stored in the refrigerator for up to 18 months.
Bottled juice — even that made from concentrate with additives — can be a successful substitute for lemon zest in many recipes, using the same general proportions as fresh juice. The smaller the amount of zest called for, the more successful the recipe is likely to be. If your recipe asks for a large amount of zest (more than a few tablespoons), you're probably better off either making a dash for the supermarket or holding off on the recipe until you have some zest in the kitchen. A lot of lemon juice can make a major change to the taste and consistency of a dish.
Be careful when using lemon juice as a substitute in baked dishes, since the acidic juice can react with baking powder and baking soda, creating a lot of air bubbles and an unappealing texture.
Bottled organic lemon juice without additives is available in many supermarkets and health food stores. It may be more expensive than other packaged juice, but it does offer a fresher taste. After it's opened, organic lemon juice shouldn't be stored in the fridge longer than two weeks. You can store it in the freezer, however, by using the ice cube tray method.