Breast milk can sometimes smell unusual, such as metallic, soapy, or rancid. This doesn't necessarily mean the milk is spoiled or unsafe.
Reasons for Unusual Smells in Breast Milk
Several factors can contribute to changes in the smell of breast milk:
- Lipase: High levels of lipase, an enzyme that breaks down fats, can cause a soapy or rancid smell, especially in stored or frozen milk. [Source: Modern Milk, KellyMom]
- Oxidation: Exposure to air can cause oxidation, leading to an off-putting smell. [Source: Australian Breastfeeding Association]
- Freezing and Thawing: The freezing and thawing process itself can alter the smell and taste of breast milk, sometimes making it smell unpleasant. [Source: Medela, Lactapp]
- Spoilage: Truly spoiled breast milk will have a distinctly sour smell, similar to spoiled cow's milk. This indicates it's unsafe to consume. [Source: WebMD, KellyMom]
While some odor changes are common and don't necessarily indicate unsafe milk, a sour smell is a clear sign of spoilage. Many mothers report their babies rejecting milk with a strong sour or soapy smell, even if it's still safe to consume. [Source: Breastfeeding Support, LLLI] The reasons behind many odor changes are still not fully understood. [Source: LLLI]
Important Note: If you are concerned about the smell of your breast milk, it's always best to err on the side of caution. If the smell is strongly sour, discard the milk.
