The shelf life of toast is 5 days. The whole wheat flour used in toast retains most nutrients because it has undergone less processing procedures. Rich in crude fiber, vitamins E and B, zinc, potassium and other minerals, it is more prone to mildew and deterioration than ordinary bread, so it must be properly preserved after purchase.

Bread packaging will indicate the shelf life: "2 ~ 3 days in the second and third quarters (spring and summer) and 4 ~ 5 days in the first and fourth quarters (autumn and winter)". When shopping, you must choose the freshest bread possible. If you bought it when it is about to expire, you should eat it immediately. Don't let the bread at home expire and get moldy. If the mall is offering a discount, it is even more important to keep your eyes open to see if it is about to expire. As far as the current bread packaging situation is concerned, preservatives are mostly added to bread with long shelf life, while bread with short shelf life is closer to the original bread practice, and food additives such as preservatives and modifiers are used less. Although these food additives are generally harmless to human body, they will also increase the metabolic burden of human body to a certain extent, so it is better to eat less.