Do not trust your sense of smell with these foods. Cured meats, such as ham or bacon, will be safe to eat even after several days without refrigeration. Eggs can be kept several days in a cool place without refrigeration if the shell is not cracked or broken. Hard cheese will usually keep well at room temperatures. Other cheeses, such as cream cheese, opened containers of cheese spread, and cottage cheese, spoil quickly.
Milk spoils quickly without refrigeration.
Do not use any milk with a sour smell or taste. Custards, creamed foods, or any foods containing mayonnaise, spoil quickly. These foods are likely growing places for organisms causing food poisoning. Throw out any of these foods if they reach room temperature. Spoilage often cannot be detected since there may be no bad odor or taste.