The white residue in frozen breast milk after thawing is not a sign of spoiled breast milk. This situation is mostly considered to be formed when the fat layer in breast milk precipitates and coagulates into clumps as the temperature decreases. When breast milk is heated properly, the fat layer will gradually dissolve in the milk as the temperature increases, and these granular substances will disappear. If these granular substances do not disappear as the milk is heated, it is considered that there may be a phenomenon of milk spoilage, in which case it should not be fed to the child and should be discarded in time. To ensure that the stored breast milk does not deteriorate, it should be stored in a cold environment as much as possible and fed to the child within a short period of time.