The musty smell of flour indicates that the flour has begun to mold. When food is infected by mold, mold multiplies and secretes metabolites, which makes food moldy. People eat peanuts, rice, edible oil sauce, flour, corn and so on. Being infected by mold often causes damage to important organs in the body and can induce cancer.

Extended data:

Mildew is a common natural phenomenon, which often appears in food. Food contains a certain amount of starch and protein, and more or less contains some water. The growth and development of molds and eggs need the existence of water and warm temperature. Moulds and eggs with low water activity value can't absorb water, but when the water activity value increases after being wetted, moulds and eggs will absorb water in food, and then decompose and eat nutrients in food.

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Baidu encyclopedia-moldy food