Food & Cooking 15 Smart Ways to Repurpose Kitchen Scraps to Reduce Food Waste (and Save Money) By Kelly Vaughan Kelly Vaughan Kelly is a former associate digital food editor for MarthaStewart.com. Editorial Guidelines Updated on March 2, 2023 Share Tweet Pin Email Trending Videos Photo: Aaron Dyer Before you toss your kitchen scraps, first consider whether they can be repurposed. After all, using those leftover bits—like Parmesan rinds or even butter wrappers—is a smart way to reduce food waste and save money, and something savvy cooks have always done. As a nation, we waste 35 to 40 percent of our food supply, says Jill Lightner, author of Scraps, Peels and Stems: Recipes and Tips for Rethinking Food Waste at Home. Find out how to cut down on this waste with these clever ideas for using leftover egg whites, coffee grounds, that last bit of tomato paste, and even onion skins. 01 of 15 Butter Wrappers Rather than discard the wrapper after you've used a stick of butter, stash it in the freezer inside a resealable plastic bag. When you need to butter a baking dish, take out a wrapper, let it soften slightly, and use to grease a cake pan or cookie sheet. 02 of 15 Cheese Rinds Do as the Italians do and add the rind of an aged cheese to a stock, soup, or sauce. Freeze leftover rinds from hard cheeses such as Parmigiano-Reggiano or Pecorino Romano, and you'll have them on hand to add to a pot of beans or minestrone soup to thicken it and impart a rich, savory flavor. Remove the rind just before serving. 03 of 15 Bread Ends Tara Donne Rather than discarding stale bread, turn it into croutons or breadcrumbs using a sharp, serrated knife or food processor. Store breadcrumbs in an airtight zip-top bag or container for up to two months. 04 of 15 Egg Yolks If you have a recipe that only calls for egg whites, save the yolks for recipes like lemon curd, chocolate mousse, or spaghetti carbonara. To prevent the yolks from gelling, add a pinch of salt (for main dishes) or a heaping teaspoon of sugar (for desserts) per every four yolks. Store in the refrigerator for up to two days. 05 of 15 Egg Whites Johnny Miller On the other hand, if you're looking for ideas for using egg whites, whip them up for Swiss Meringue Buttercream to frost a cake or cupcakes, use them to make a pavlova, or turn them into a healthy egg white breakfast scramble. 06 of 15 Citrus Zest After you've squeezed all of the juice from a lemon or lime, freeze the spent halves in a resealable plastic bag (for up to three months). Grate the desired amount of frozen zest the next time you have a recipe that calls for fresh zest. 07 of 15 Extra Chocolate You have leftover chocolate from baking, but it's not enough to make the same recipe again. Don't toss the leftover piece! You can instantly elevate any dessert with fresh chocolate curls. For longer curls, melt the chocolate, then pour it onto a flat, smooth surface and spread it to a thin, even thickness. Once cool, slowly scrape the chocolate up with a bench scraper. 08 of 15 Onion Skins To give a broth or soup base a deeper, more amber hue, leave the skin on the onions after you've cut them into halves or quarters. The skins will beautifully color the stock; strain before using. 09 of 15 Eggshells Ryan Liebe Use eggshells as pots to start seeds. Plant seeds according to package instructions, and nestle planters in an egg carton on a sunny windowsill, where they can be watered easily. The first leaves to sprout will be the cotyledons or seed leaves, which supply nutrients to the young plant until the first true leaves (resembling those of the parent plant) appear. When plants have grown to about 3 inches and have at least two sets of true leaves, they are ready to be transplanted to the garden. 10 of 15 Tomato Paste Jen Causey When your recipe calls for just a small amount of tomato paste, the rest of the can may go to waste. Make sure this doesn't happen by opening both ends of the can using a can opener. Remove one metal end and discard it. Wrap the entire can in plastic wrap and freeze overnight. The next day, use the other metal end to push the frozen paste out the open end. Discard the can, tightly rewrap the unused portion, and store it in freezer for up to three months, slicing off just as much as you need each time you cook. 11 of 15 Cake Trimmings Lennart Weibull The next time you bake a cake, don't toss the trimmings into the trash. Keep them to use as building blocks for another dessert, such as a trifle layered with whipped cream and fresh raspberries. You can freeze cake pieces in an airtight container for up to one month. 12 of 15 Vanilla Bean Pods Lennart Weibull Once you've scraped the beans from vanilla pods stick the pods in a container of granulated sugar, this will infuse the sweet stuff with natural vanilla flavor. Or make your own vanilla-infused simple syrup to mimic the sweetener used for an iced coffee or latte at your favorite coffee shop. 13 of 15 Coffee Grounds Bryan Gardner After brewing a fresh pot of coffee, make a coffee body scrub, oil, or soap using the grounds. It works wonders as a natural exfoliant for your body or lips. 14 of 15 Bones and Shells Instead of discarding a chicken carcass or beef bones, or the shells of lobster or shrimp, save them for a flavorful beef, chicken, or seafood stock that you can use for soup, risotto, or pot pies. Gather the bones in a freezer bag, label it, and stash it in your freezer until you have time to make stock. 15 of 15 Vegetable Scraps Aaron Dyer Save carrot tops, celery leaves, onions, garlic, and leftover herbs or herb stems to use for a quick vegetable stock. First, pulse the vegetables in a food processor until finely chopped. Then fill a saucepan with about twice as much water as you have vegetables, bring to a boil, and stir them in. Was this page helpful? Thanks for your feedback! Tell us why! Other Submit