Lemons top the list of the five foods I’d want with me should I ever find myself deserted on an island.

I figure I’d be eating a lot of seafood while stranded on said island and lemons are the perfect pairing for fish. But also, I’d use lemons to flavor the local spring and coconut waters I’d be sipping in the sunshine. And I could use spent lemon halves (mixed with the sea salt I’d have all the time in the world to evaporate from the surrounding ocean) to disinfect the bamboo cutting boards I’d have pressed together for use in my makeshift island kitchen.

Picking five foods, from all the options on the global market today, that you wouldn’t want to live without is a fanciful exercise. If you care to know, my other four would be sushi rice, garlic and tomatoes, for sure, with red wine and milk chocolate duking it out for the final spot on the team. But since I don’t typically carry any of these things on my person, it’s highly unlikely I’d ever find myself stranded anywhere with them.

Back here in the real world, I must admit that lemons don’t naturally grow on trees in Maine. A more fruitful green-eating mental exercise might be thinking about my top five lemon substitutions.

Let’s get the hard truth out of the way first, folks. There is no real substitute for lemons when making lemon tarts and lemon bars. Well, there are limes, but in Maine we’ve got the same non-local situation with those. While you can substitute for the brightness a lemon (or a lime) adds to savory dishes and the chemical reaction citric acid in lemon juice triggers when baking (more on the later, too), it’s nearly impossible to recreate the lasting sweet-tart flavor of lemon when it’s mixed in the right proportions with sugar.

Substitute these ingredients for lemons, depending on what you’re cooking: Sumac, white vinegar, white wine, apple cider vinegar or whey. Photo by Christine Burns Rudalevige

Moving to the savory side of the menu, though, your best 1:1 substitution for lemon juice in dishes that don’t require cooking (like hummus, pesto, berry puree, or sweet pea mash is white vinegar, which, chemically speaking, has relatively the same amount of hydrogen ions in play and therefore a similar acidic bite. If you want a slightly softer bite and a smoother edge in these uncooked dishes, use apple cider vinegar in the same ratio.

In cooked dishes (like sauces for seafood or chicken created by deglazing the pan the protein was cooked), it’s best to run with a dry white wine like sauvignon blanc, pinot grigio or pinot gris, when lemon juice is called for. Keep in mind that it will take twice as much dry white wine (and time to reduce the sauce) as the amount of lemon juice listed in the recipe to achieve the same results.

Another, and arguably more hyper-local lemon replacement for lemon juice in savory dishes, is whey, the liquid leftover from making fresh cheese or straining yogurt. I can’t give universal replacement ratios for whey, though as whey will vary in acidity (and salt content) based on the curds it was separated from. Best to taste your whey before adding it to your dish so you understand just how sour and salty it may be.

If your recipe calls for a quick squeeze of lemon juice to finish the dish so that all the other flavors pop, you’ve got two interesting options. Chopped fresh cilantro (sometimes called fresh coriander in both recipes and on grocery store labels) stirred in at the very last second will do the trick. In the heat of cooked dishes, like chili, curries or spicy soups, these tender leaves quickly lose their flavor, so serve the dishes right away for best results.

Sumac, a bright-tasting spice made from reddish berries of non-poisonous sumac trees, is widely used in Middle Eastern cooking and is available from local spice merchants like Gneiss Spice in Bethel, Gryffon Ridge in Dresden and Skordo in Brunswick and Portland and is grown locally at Goronson Farm in Scarborough. You must sprinkle sumac liberally over fish, kebabs and salads just before they are served to achieve the lemony pucker. And that liberal application is even more important for baked goods and cooked sauces.

Give this lemony spice a whirl in the Double Sumac and Raspberry Snacking Cake. Perhaps you’ll like it enough to make it one of your desert-island foods.

After the cake has cooled, pour the Raspberry-Sumac Glaze over it. Photo by Christine Burns Rudalevige

Double Sumac and Raspberry Snacking Cake

If you need a nut-free option for this cake, substitute an equal amount of whole wheat flour for a nutty taste, omit the almond extract and increase the yogurt to 1/2 cup to maintain the moist texture.

Makes one (8-inch square) or one (9-inch) round cake

FOR THE CAKE:
12 tablespoons unsalted butter, softened, plus more for greasing the pan
1 ½ cups granulated sugar
3 large eggs, at room temperature
½ teaspoon vanilla extract
¼ teaspoon almond extract
1½ cups all-purpose flour, plus more for pan and coating the whole berries
½ cup almond flour
2 teaspoons ground sumac
1/2 teaspoon kosher salt
1/3 cup plain yogurt
1 cup frozen raspberries

FOR THE RASPBERRY-SUMAC GLAZE
1 ½ cup frozen raspberries
1/2 cup sugar
¾ teaspoon ground sumac

Preheat the oven to 325 degrees F. Lightly butter and flour an 8-inch square or 9-inch round pan.

To make the cake, combine the butter and sugar in bowl of an electric mixture. Beat butter and sugar on medium speed until pale and creamy, 2-3 minutes. Reduce the mixer speed to low, and add eggs, 1 at a time. Add the vanilla and almond extracts.

Whisk together all-purpose flour, almond flour, sumac and salt in a medium mixing bowl. Add half of the flour mixture to the batter. Beat on low speed just to combine. Add the yogurt. Beat on low speed just to combine. Add the remaining flour mixture, again beating on low speed just to combine. Toss the frozen raspberries with a tablespoon of flour and use a rubber spatula to fold them into the batter.

Transfer the batter to the prepared pan and bake until a wooden pick inserted in center comes out clean, 40-50 minutes. Cool cake in pan for 10 minutes; remove from pan, and cool completely on a wire rack.

To make the glaze, combine the raspberries, sugar and 1 tablespoon water in a small saucepan over medium-low heat. Stir the mixture as it heats up, the sugar melts, and the berries break down, and the glaze starts to thicken, 7-8 minutes. Remove from heat and stir in sumac. Let the glaze stand for 5 minutes before spooning it over the cooled cake.

Local foods advocate Christine Burns Rudalevige is the editor of Edible Maine magazine and the author of “Green Plate Special,” both a column about eating sustainably in the Portland Press Herald and the name of her 2017 cookbook. She can be contacted at: cburns1227@gmail.com