Rhubarb-Lime Marmalade with Ginger
This piquant sweet-and-sour marmalade combines fresh limes and rhubarb with a bit of ginger zing. It is somewhat labor-intensive, but adds a brilliant zest to your morning toast. By Joshua McGee.
Rhubarb-Lime Marmalade with Ginger by Joshua McGee
- 600g fresh, unblemished limes, plus more for juice
- 400g trimmed rhubarb stalks
- 1.4 liters of filtered water
- 1700g granulated white sugar
- 2cm length of ginger rhizome, peeled and cut into four slices
- Heavy medium stock pot
- Large stock pot
- Silicone spoon and ladle
- 5 – 6 pint (½ liter) canning jars with lids and rings
- Circular rack, or clean kitchen towel, for jar sterilization
- Citrus reamer or citrus press
- Mandoline (optional)
- Very sharp knife
Scrub limes with a vegetable brush (yes, even if they are labeled as organic). Cut in half and juice with a reamer or press.
Peel membrane off of rhubarb stalks and slice, crosswise, as thinly as possible. You can use your mandoline's thinnest setting, or spend a lot of time and patience with a very sharp knife. Place in a large glass bowl.
Cut the pointed tips off of the lime halves and discard the tips. Cut the lime halves in half again, and slice thinly. Add to the glass bowl.
Measure the volume of your lime juice, then add the juice of more limes until the volume of lime juice is 600ml (you can discard the peels of these limes.)
Add the lime juice, water, and ginger to the bowl and stir. Transfer to heavy pot. Bring to a boil over medium-high heat. Cover pot and reduce heat to lowest setting. Simmer for one hour to soften lime peels and rhubarb. Remove ginger slices.
Slowly stir in sugar, at low temperature, until dissolved (this may take up to ten minutes). Increase heat to medium-high again; bring syrup mixture to a boil; and boil uncovered at medium-high heat for 45 minutes – 1 hour, stirring frequently (at least every five minutes) to keep the sugar from sticking to the bottom of the pot.
While the marmalade is cooking, sterilize your canning jars in the large pot via water immersion. The steps for sterilizing and canning are beyond the scope of this post, but there are plenty of guides online.
Once the boiling marmalade reaches 105°C on a candy thermometer, stir thoroughly, extinguish flame, and ladle into your sterilized jars. Apply lids and rings (per a reliable guide) and process in boiling water for five minutes. Remove and set jars aside to cool for 24 hours at room temperature, following all the normal safety steps and checks.