I am a notorious cheapskate.
I started my first restaurant job at 14, and, by 18, the Book of Yields was my grimoire. I learned how to stop profits from vanishing into thin air, how to maximize every return. If you're in this industry long enough, battling food cost simply becomes a way of life. Particularly in the realm of pastry, where wildly expensive necessities often break the curve—fresh cream and butter, imported chocolate and vanilla, flats of local eggs and fat spring strawberries.
Which is how I stumbled into the habit of making fresh lemon syrup from leftover lemon rinds, just the sort of thing a penny-pinching pastry chef would come up with at home. Home, because in my restaurant days, I'd always zest my lemons before juicing, or else carefully peel them for candy, so I never felt too bad about pitching the pithy rinds. But, living outside the pastry dungeon, my resentment of having to pay retail for citrus has grown to an all-time high, while my need for candied peel has hit an all-time low.
That cocktail of frustration and thrift saw me hoarding lemon rinds in a bowl, stubbornly refusing to toss them out despite having no clear purpose for them in mind. The mountain grew with every batch of lemon bars that I tested, retested, and tweaked (recipe here), until my husband was convinced I lacked the strength to part with the rinds on my own. He dragged a trash can to my side, gesturing to the bowl, palms spread and pleading.
"What are you waiting for," he implored, Samwise to my Frodo. "Just let it go!"
But I couldn't see past the golden glow, nor could my greed be overcome. The rind was mine!
A used lemon rind may not seem precious to you (wicked! tricksy! false!), but toss one into the garbage disposal and consider the instant blast of springtime freshness Exhibit A—proof positive that we're all flushing essential oil down the drain, then paying out the nose to buy it back again, one teeny-tiny bottle at a time.
Or, at least, that was my first thought when I was forced to part with my lemon rinds or come up with a plan on the fly. So I threw in a few cups of sugar and hoped that science would kick in and reward my determination with something juicy-sweet.
Sugar's too hygroscopic to just sit there. I knew it would draw out whatever juice the rinds had left to offer, maybe even a bit of essential oil. Nothing to rival the intensity of commercial, expeller-pressed oil, but certainly enough to boost the aroma of my lemon bars with some citrus-scented sugar.
What I didn't expect was that within a few hours, the sugar would dissolve completely, leaving me with a full pint of liquid sunshine: thick and yellow and sweet, but tempered by the natural astringency of the pith. The rinds seemed almost rehydrated, so plump with syrup that I crushed them in a potato ricer to squeeze out every last drop.
I was all but vibrating with glee as I bottled it up.
See, unlike any other sort of homemade syrup, the technique I stumbled upon—one I later learned was a sort of quick and dirty oleo-saccharum—didn't require adding any juice or water to the rinds. Fourteen ounces of sugar went in, 16 ounces of syrup came out; as close to alchemy as I'll ever come.*
* Of course, that's not how science works, and I knew that at least a portion of the syrup was surely juice. My obsession with The Book of Yields taught me that some of the sugar and syrup was inevitably discarded with the rinds, so it wouldn't be a simple matter of addition and subtraction to determine the final percentage of juice. Even so, from the syrup's viscosity alone, I can presume the juice content to be very low. And, given what I know about its low juice and high sugar content, I suspect that citric acid in the rinds may have partially inverted the syrup, since I've yet to have a batch recrystallize.
The syrup was luscious and, well, syrupy! Clearly more sugar than water, and thus amenable to recipes that won't tolerate any significant quantity of water or juice. Like, say, whipped cream.
What followed was nothing short of an infomercial as I ran around the kitchen dorking out over the possibilities of my fresh lemon syrup. Oh, look, a French 75! How about some crystallized violets? Maybe I should make lemon chantilly, or pancake syrup? Hot damn, now we're talkin' brunch. Mmmm, brunch, I bet it could make a nice lemon poppy seed vinaigrette, or a glaze for salmon....
But, wait, there's more!
Honestly, there really is. Since then, I've discovered that fresh lemon syrup is a fantastic addition to homemade granola, a replacement for cream in white chocolate ganache, a complement to sweet tea, and a worthy part of almost any sorbet. Because the syrup is never boiled to dissolve the sugar or reduce the juice, it doesn't take on any of that slow-cook funk that ruins so many fruity desserts. Its flavor stays pure and clean, adding a burst of lemony sweetness to everything from marinades to cocktails and candied pistachios, without ever watering them down.
Since the syrup's mostly sugar, it produces a crispier shell than candied nuts that call for simple syrup, while in cocktails, its one-two punch of sweetness and flavor simplifies the common combination of simple syrup and lemon juice.
Wringing out every ounce of value may only seem important to you after paying up for cases of pricey citrus, like Meyer lemons (which make an intensely aromatic syrup), but you don't have to be managing food cost like a pro to appreciate having a bottle on hand—plus, my recipe truly shines with workaday supermarket fruit. So, the next time you find yourself juicing a big bag of lemons for meringue pie, or even just a handful to make garlicky tahini, do me a favor and don't toss out those precious rinds.
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