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Raw black beans are harvested from the ground. As a result, it's not uncommon to find small pebbles mixed in with them. To make sure your bagged beans are safe to eat, spread them out on a baking sheet and sift through them by hand, picking out any small rocks you come across. You don't want to sink your teeth into one by accident! Most rocks will be light gray in color, which helps them stand out easily from the dark beans. It's a good idea to give the beans a quick rinse prior to soaking, especially if they're visibly dirty. A preliminary rinse will sanitize the beans and start breaking down the waxy starches coating the outside of the beans that makes them take longer to cook. Stir the beans up from the bottom by hand as you rinse to make sure the water gets distributed evenly throughout. A good long soak may make a separate rinse unnecessary if you're planning on cooking the beans immediately. The container you choose should be spacious enough to hold the beans you plan on soaking, along with the water that you'll be adding later on. In most cases, a serving bowl, saucepan or stockpot will provide the volume you need. Measure the beans out into cup-sized portionsthis will make it easier to round off your other measurements. A standard serving of black beans is about cup (75g). Unless you're fixing mass quantities in bulk, plan on soaking all of the beans at once. Breaking them up into multiple batches can add hours to your prep time. Drizzle 1 tablespoon (15ml) of distilled white vinegar or lemon juice over every cup of dried beans. The mild acid will help soften the beans before they even hit the water, while also ensuring that the water heats evenly. A little acidity will also prevent the beans from becoming mushy or completely disintegrating if they're overcooked. Fresh squeezed lemon juice is preferable as it doesn't contain any other additives, but bottled will also work just fine.
Check the black beans for rocks. Wash the black beans in a colander. Pour the black beans into a large bowl or pot. Add a small amount of acid.