Key Lime Marmalade


I never quite understood marmalade. It was one of those things the early pioneers must have made: fresh fruit was precious, the vitamins scarce, and therefore even the seemingly inedible peel had to be used in any way possible. So they’d chop it up, boil it down into a thick goop, and eat it on toast. And to add insult to injury, the peel’s offensive, acerbic bitterness was masked with an obscene amount of sugar to make it even barely palatable.



No, thank you. Sugar-soaked garbage is still garbage.

Perhaps I was being a snob. But thanking the gods of modern agriculture (and our glorious Mediterranean climate), I was content to enjoy only the juicy, sweet citrus flesh that is always available in abundance, and (because I have always been an ecologically responsible snob), whisk the peels away to their duty in the compost bin.

So certainly I was surprised when Rick told me that though he loved all the jam I was making, he really missed having toast with marmalade. I mean, Rick generally has pretty good taste and there are very few things that he enjoys eating that I do not. So was I missing something? Was there some magic in those sticky, slimy bits of castoff peel that I had previously not experienced? I knew that lemon zest was a wonderful thing, but…marmalade? Maybe I could find a way to make it work.


So I read recipes. And more recipes. 13 cups sugar to 8 cups water and pulp. Add gelatin. Add pectin. Use a food processor. Use a cheese grater. Don’t make it, buy it. 1 lb sugar for every half cup of pulp. Never EVER use anything other than Seville oranges or Spanish ghosts will haunt you forever (and force-feed you marmalade made the right way)…

…there is seemingly a lot of argument in what the “right” way is. I will not get into a huge diatribe about the history (other than a mention of the fascinating etymology that brought us the name “marmalade“), but I will tell you that after trying out many recipes and a LOT of prep time I have finally come upon a recipe that is right for me. Not too sweet, not too bitter. Spreadable on toast, but not drippy. Never cloudy, never off-color. Keeps in a jar in the cupboard for up to a year.

This recipe, and the culinary journey that produced it, have changed marmalade for me completely. It is now something that I enjoy quite a bit (plus it makes Rick awfully happy to have it around the house)!


Key Lime Marmalade
4 c prepared citrus (see below for instructions)
4 c water
4 c sugar (or white evap. cane juice)

This recipe works well with any citrus, and the directions are the same for all kinds. Feel free to experiment with mixing several types of fruit, including grapefruit, eureka or meyer lemons, standard or key limes, tangerines, kumquats, or any type of orange (blood orange marmalade would be beautiful). Make sure to wash the fruits thoroughly before starting this process, as the peel is incorporated into the recipe and not discarded.

Not sure how much fruit you should start with? Here are some basic amounts that would give you the right amount of marmalade-fodder:
3-5 large thin-skinned grapefruit
5-6 large thick-skinned grapefruit (you will not use the white spongy pith)
5-8 large oranges
8-10 regular oranges, blood oranges, or large lemons
10-15 small lemons, tangerines, or large limes
15-20 key limes

To prepare the fruit:
Using a paring knife, carefully peel the citrus leaving as much of the white pith attached to the fruit as you can. The object here is to only take off strips of the “zest” part of the peel. Finely julienne the slices of zest, either long- or short-ways (depending on your degree of comfort using a knife and the intended aesthetic of the finished marmalade – long, thin strips are the toughest to accomplish, but make the prettiest preserves). Section out the citrus following a basic suprême method: remove the pith, collect all the juice and flesh, and leave all the membranes and seeds behind.

Depending on the ripeness and size of the fruits, the supremes might be able to be slid out by hand without too much fancy knifework. The limes I was working with were fairly easy to section out by hand.

Place the julienned zest, the supremes of flesh, and any juice into a bowl roughly twice the volume of the lime mixture. Add enough water to cover the mixture, which should be around 4 cups and appear “soupy”. This recipe is VERY basic, and can be adjusted to any amount you wind up with after preparing the fruit; just adjust the water and sugar accordingly.


At this time, you may add any other flavors you’d like. I *love* grapefruit marmalade with fresh-grated ginger. I also made some lime marmalade with a pinch of salt and a fresh jalapeño (diced finely, seeds and all), which I intend to use as a condiment for meats or an addition to a grilling glaze.

Cover this with a lid or plastic wrap, and leave for at least 4 hours (it’s better overnight). This resting period leaches some of the bitterness and softens the zest, making the final marmalade quite palatable. It also allows the flavors of the different citrus and spices to meld together.

Once the mixture has rested, transfer it to a non-reactive stock pot that is at least double the capacity of the marmalade (once it starts to boil, it can increase in volume very quickly and is napalm-hot). Add an equal amount of water by volume (you can eyeball it), and a little less than an equal amount of sugar. It takes FAR less sugar than most recipes call for to make a sturdy marmalade – there is quite a bit of pectin in citrus.

Simmer the mixture over medium heat until it reaches its jelling point, which is 8 degrees above boiling on a candy thermometer (roughly 220 degrees Fahrenheit), or until a small amount dropped onto a cold plate and placed in the freezer for 1-2 minutes forms a solid “skin” that wrinkles when it’s poked at. With some practice making jams/jellies without added commercial pectin, you’ll be able to tell a jelling point by the sound and appearance of the bubbles and won’t need to check with these other methods.

(Nifty little tip: take some basic commercial jelly out of the fridge and melt it in a pan until it’s a bubbling liquid. THAT’S what jelling point looks/sounds like. Now pour it over a fruit tart. There y’go. Yum!)

Carefully transfer the very VERY hot marmalade into sterilized jars and fill to within 1/2 inch of the top. Making sure the edge is clean (I LOVE my canning funnel!), place the lids on the jars and screw down tightly. If you are planning on putting these up for later, process them in a basic water-bath canning system for 10 minutes. Here are some basic safety guidelines regarding canning, provided by the National Center for Home Food Preservation. Read this before you attempt to can any kind of food on your own – canning is easy and fun, but can be very dangerous if done incorrectly.

Key lime marmalade on a toasted whole wheat/oat roll. Dee-lish.




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