Split peas are a low-fat source of protein and are generally considered a healthy food. Like all other dried beans, however, they contain complex sugars that the human body finds difficult to digest. The gas produced by their digestion can cause bloating and flatulence. Unlike other dried beans, split peas do not require soaking before cooking. However, soaking split peas can help to reduce the amount of gas produced by dissolving the outer coating that contains the complex sugars..
Sort through the split peas, discarding any foreign material such as small rocks or stems that are mixed in with the beans. Rinse the sorted beans under cold running water.
Place the rinsed beans in a bowl, and cover with cold water. Put the bowl in the refrigerator overnight, or for 8 to 10 hours.
Pour the beans and water through a colander to drain the soaking water. Rinse the soaked beans, agitating them with your hands in the colander, to make sure that all the soaking water with the dissolved sugars is cleaned off.
Reduce the cooking time indicated in your recipe by 10 to 15 minutes. Split peas do not require soaking before cooking, so most recipes will assume you are starting with dried peas. If you are cooking a soup, this won't be an issue as you want mushy beans, but for other recipes you'll want to check the split peas as they cook, to make sure they don't become too soft.
Don't use a pressure cooker to cook soaked split peas unless you are making soup. Soaking before pressure cooking will produce very mushy split peas. Make sure to use enough water when soaking the split peas. A good rule of thumb is to use three cups of water for every cup of beans.