What exactly is citrus zest? is there an alternative to using zest when a recipe calls for it? what's the best way to get it off the fruit? can you freeze it?
Zest is the very outermost layer of a citrus fruit's skin. Beneath the colored zest is the spongy white (and bitter) pith, and beneath that is the fruit's flesh. Zest is full of intense flavor; this is where the oil of a citrus fruit resides.
Why would you want to use, say, lemon zest instead of lemon juice in a recipe? When you add lemon juice, you not only add lemon flavor, but also liquid and acid -- which can alter the taste and chemistry of a mixture. If you want only the flavor of lemon, pure and simple, you use zest.
Recently, I tested the tools I've accumulated that can be used to remove the zest from a citrus fruit. An actual zester is a little gadget that, when pressed against and dragged along the fruit, actually peels off little strips of zest. It's nice to have something called a zester, and you do get nice little curlicues of zest, but it's not very efficient.
The box grater is definitely the zester of last resort. I have three Microplanes of varying finenesses, and they all did a really good job of removing a very fine layer of zest. My go-to vegetable peeler, a Kuhn Rikon with a horizontal blade, did a respectable job, but my two swiveling vertical-blade peelers left it in the dust. This is my preferred method if I need large pieces of zest or thin slices, in which case I stack up a few layers of zest and, with a sharp knife, make very fine julienne strips.
You can freeze zest in any form. I wrap mine tightly in plastic wrap, then place that package in a sealable plastic bag from which I've sucked out as much air as possible.
Erica Marcus writes for Newsday. E-mail your queries to firstname.lastname@example.org, or send them to Erica Marcus, Food/Part 2, Newsday, 235 Pinelawn Road, Melville, NY 11747-4250.