Citrus season is winding down, and I am bummed about it. I have been gorging on Sumo citrus for weeks now, trying to cram as much vibrant, tangy sweetness into my mouth as possible until the bumpy fruits disappear for the year.
In an attempt to prolong the joy Sumos bring me, I’ve even been saving their peels. They may not be juicy and sweet, but they still have a ton of flavour hanging out in their cellular walls, waiting to be extracted — and you can do that with a little sugar. Sugar pulls the oils out of the peel, and said oil in turn dissolves the sugar, creating a syrup fancy bartender types call “oleo saccharum.” You can measure everything out — which we discussed here — but you can also just chuck it all in a jar, shake, and strain when you remember.
I prefer the latter method, obviously.
Gather your peels and remove them from the pith (the white part on the inside) with a y-peeler (or cheese slicer) as much as possible. The pith can give your syrup a bitter flavour, so try to avoid including thick swaths of it.
You can make a little syrup or a lot of syrup, depending on how many peels you have. If you want to make a lot of syrup, stash your peels in the freezer until you have whatever amount you deem to be “enough.” A couple of citrus fruits will give you a couple of tablespoons of syrup, depending on how much zest they have to offer.
In any case, all you have to do is toss your peels into a jar and add a spoonful of sugar. Shake the jar to rough up the peels and coat them with sugar; you want each strip to sparkle with sucrose, with a little excess at the bottom of the jar. If your peels are not fully coated, add more sugar and shake the jar again.
Let the jar sit for several hours — or all night — gently shaking it a couple of times as you remember to do so. The longer your extraction time, the more likely you are to extract bitter flavours, though I left a jar of lemon peels extracting for several days and it tastes just fine.
Strain the peels out of your syrup, then use the fragrant, sweet, and slightly floral liquid to sweeten cocktails, tea, or plain seltzer. You can also drizzle it on desserts and baked goods like cake, ice cream, or pancakes.