Mashed potatoes are a comfort food staple that can be made in large quantities ahead of time and reheated for easy, fast meal prep. When stored properly, they last about 3 to 5 days in the fridge before their quality starts degrading.
If your mashed potatoes have gone bad, it is important to recognize the signs that they are no longer safe to eat. One of the first indications is a sour or bitter taste. This may be the result of bacteria growing in the potatoes, which can cause an unpleasant odor and lead to stomachaches or other health problems.
Another sign is discoloration. If your mashed potatoes are starting to lose their bright white or golden color, they may have gone bad. You can also test the mashed potatoes by tasting them. A sour or bitter flavor is a sure sign that the potatoes have gone bad and should be thrown out.
In addition to delivering essential nutrients, such as vitamin A and several B vitamins, mashed potatoes contain fiber, which helps keep your digestive system healthy and regular. A half-cup of mashed potatoes provides 6 percent of your daily value of vitamin A, which helps promote eye health and boosts immune function. It also offers potassium, which plays a role in maintaining heart health by keeping blood pressure levels low. If you have leftover mashed potatoes, it is best to store them in the refrigerator to prevent spoilage and maintain their high nutritional content.