If life gives you lemons, make lemon confit.
Or preserved lemons, as I've otherwise seen them called. But Eric Ripert calls it lemon confit, and his was the recipe that caught my eye the other day as I flipped through his book A Return to Cooking. I happen to have a bunch of the fattest, juciest lemons I've ever seen in my refrigerator, freshly picked by my brother and sister-in law in Florida from a tree in their yard. So I had lemons on my mind as I read Ripert's book.
I've seen several versions of this preparation, all of which are attributed to Morocco. Ripert's method is the simplest: Quarter the lemons and layer them with lots of kosher salt in a canning jar, then seal and refrigerate for at least a month, preferably three. The lemons will keep for up to a year.
Sound tasty? Maybe not at first. But according to Ripert, the result is a condiment that gives you all the flavor of the lemon without the acidity. Before using, rinse away the salt and scrape off the excess flesh to leave the dried-out rind, which is the part you want.
The procedure is interesting because it combines two distinct methods for preserving food: salt curing and canning.
Curing works by drawing the moisture out of foods, which inhibits spoilage, since bacteria, like anybody else, need water to live.
Canning works by sealing foods in a sterile, typically airless environment. No bacteria, no oxygen, no spoilage. Canning works very well -- the food can theoretically last indefinitely -- but you have to be careful. While the lack of oxygen prevents most bacteria from growing, it opens the door to certain bacteria (called anaerobic bacteria) that actually thrive in an oxygen-free environment. The most notorious of these, Clostridium botulinum, produces the deadly nerve poison -- better known as Botox nowadays -- that causes botulism. (That's right, the same toxin that can kill you can be used, in carefully-administered doses, to paralyze the muscles in your face. This results, oddly enough, in younger-looking skin.)
To avoid botulism, or any other bacterial growth, you can make sure the food is sterile by heating it to 240°F in a pressure cooker before sealing. For very acidic foods, such as tomatoes, many fruits—and yes, lemons—ordinary boiling will do, since the acidity also helps to inhibit bacteria. (Boiling water never gets hotter than 212°F, which is why you need a pressure cooker to hit the higher temperature needed for non-acidic foods.)
Ripert's procedure, however, doesn't say anything about heating or boiling at all. So are we really canning here, or does he just want us to use the canning jar as a handy, easy-to-seal container? And if we just fill the jar with salt and lemons and then seal, it won't be airless in there, either. Although presumably any bacteria that grew in there would eventually use up all the oxygen. And will the lemons keep for a year even after you open the jar?
Am I overthinking this? Of course. But what do you expect from a guy who writes a whole blog dedicated to margarine?
Truth be told, I'm not really all that worried. I'm pretty sure that between the acidity of the lemons and all that salt, bacteria won't have much of a chance whether you seal the jar or not. It's just that I like to know how stuff works. I've seen several other procedures for preserved lemon that do call for boiling, so it might be interesting to try it both ways and see if I notice a difference. But first I need to get my hands on a large canning jar.
And don't panic. If you ever do come across a can that's infected with botulism, you'll be able to tell because it will be bulging at the ends from the pressure of the gases produced by by bacterial metabolism, kind of like a soda can that's been shaken or carried too high up a mountain. I've never seen one, but if you ever do, just throw it away.
Those lemons you speak of from our Florida garden are called Ponderosa Lemons. Do you want to put in a yearly order? With love from your sister-in-law
Posted by: Kiki | January 12, 2005 at 02:14 PM