In 1908, Frank Nicholas Meyer, a professional food explorer, brought a decorative Chinese hybrid of mandarin and lemon to the U.S. For the next seven decades, Meyer lemon trees continued to be thought of as mostly ornamental plants. Productive trees grew almost exclusively within California, and it wasn’t until Alice Waters started using them did Meyer lemons begin its slow, but steady courtship with the broader culinary world.
Meyer lemons are less acidic than the standard lemon, and have bright, thin skins with an aromatic, almost herbal scent. The description hardly does it justice. Meyer lemons are delightful. As their season wanes, save a dozen or two to preserve.
Sugar preserves the lemons, and pectin is what makes it into marmalade, instead of just a glass of sugary juice full of peels. Pectin occurs naturally in the rind and seeds of citrus fruits, and there’s enough in the lemons of this recipe to keep you from having to supplement it with a store-bought thickener. The trick with marmalade is giving pectin enough time to develop and boiling the juice and sugar to 220° F so the mixture gels together as it cools. Unless you plan on immediately eating the whole batch, the jars must be sterilized and processed to keep bacteria from forming in the damp, dark recesses of the stored container.
This recipe has always worked for me, but don’t double it. Volume and proportion relative to heat is important for getting the marmalade right. Besides normal marmalade uses, you can also stir this into some bubbly water for an off-season lemonade or use it to sweeten cocktails.
Put two glass plates in the freezer. Make sure you have a 5-quart non-reactive pot, 6 ½-pint sealing jars, cheesecloth or a coffee filter, and kitchen string.
Ingredients: 6 Meyer lemons (1 ½ lbs.); 4 cups of water; 4 cups of sugar
1. Quarter each lemon lengthwise. Remove the seeds and collect them in the cheesecloth. Tie the little bag of seeds with kitchen string and place it in the pot.
2. Thinly slice the lemons and scoop them into the pot. Cover the pot and let the lemons soak with the seeds on the kitchen counter for 24 hours.
3. With the seeds still in the pot, bring the lemon mixture to a boil, then turn down the heat and let it simmer for about 45 minutes. Stir in the sugar and boil over moderate heat for 15 to 30 minutes. At this stage, the sugar thickens and will not gel when cool until it reaches the right temperature. You can test this with a candy thermometer, or by putting a few drops onto the frozen plate. If the drops turn to jelly on the plate, the marmalade is good to go. The longer you cook it, the more caramel-y and solid it gets. I think the marmalade tastes best erring on the lighter side.
4. While the marmalade simmers, sterilize the jars. The method differs depending on the jars you use, but the point is to boil off absolutely all the bacteria in the jars and lids before filling.
5. Ladle the hot marmalade into the jars until they are ¼ inch from the top. Wipe the rims with a damp cloth and place the lids.
6. Jars need to be processed in a water-bath canner to activate the rubber seal. This is essentially a large pot with a wire rack set at the bottom to keep the jars from making direct contact with the heat source. Water should be filled at least an inch above the top of the jars. Bring the water to a boil, and boil the jars for 5 minutes. Remove the jars with tongs and let them cool completely on a rack. The marmalade should gel as it cools, and opened jars should be stored in the refrigerator.