To keep your cut-and-bagged salad fresh, you have to reduce the moisture inside the bag. This is because moisture contains the bacteria that promotes decomposition. To get rid of the moisture, put paper towel in with your cut salad. The paper towel will absorb the moisture, helping to keep your salad fresh longer. Change the towel if it gets fully wet. Check out more info and the other ways paper towels can help your salad below.