When picking a fresh tomato you want to make sure it is firm and free of blemishes. If you come across a tomato that has cracks or splits they are not bad but these tomatoes can be used for canning or making tomato sauce. A bad tomato may look puckered, wrinkled, mold, black or green splotches of fuzz, or be oozing an oil like liquid..
To prevent spoilage and mold growth during storage, it is best to wash tomatoes just before you eat or prepare them. Then wash all whole tomatoes thoroughly in a clean sink under clean, cool running water, even if you do not plan to eat the skins. Gently rub each tomato with your hands to help remove dirt and bacteria
Store tomatoes at room temperature on a countertop. Do not refrigerate tomatoes. Refrigerating tomatoes damages the membranes inside the fruit walls, causing the tomato to lose flavor and develop the mealy texture.