How Long Does Dry Milk Last?
Dry milk, also known as powdered milk, boasts a remarkably long shelf life. While manufacturers typically suggest using it within 18 months, this is merely a "best-by" date, not a true expiration date. The actual shelf life depends significantly on storage conditions.
Under optimal storage conditions (cool, dry, and dark), dry milk can last for a considerable time. Several sources indicate a shelf life ranging from 2 to 10 years, and the USDA even suggests it can be stored indefinitely. However, this doesn't mean the quality remains optimal. Factors like fat content influence how long the milk retains its best flavor and nutritional value.
Factors Affecting Shelf Life:
- Fat Content: Whole powdered milk, containing fat, will spoil faster than nonfat powdered milk. Whole milk powder may only last a year, whereas nonfat dry milk can last much longer (at least 10 years, according to some sources).
- Packaging: Packaging significantly impacts shelf life. Mylar bags with oxygen absorbers are ideal for long-term storage, extending the shelf life considerably.
- Storage Conditions: Maintaining a cool, dark, and dry environment is crucial. Heat, moisture, and light can accelerate spoilage.
Reconstituted Milk Shelf Life
It's crucial to differentiate between powdered milk and reconstituted milk. Once dry milk is mixed with water, it becomes highly perishable. Reconstituted milk should be refrigerated and consumed within 4-5 days to prevent spoilage and bacterial growth.
Beyond "Best By" Dates
Remember that "best by" dates indicate peak quality, not safety. Dry milk that's past its "best by" date may still be safe to consume, provided it's been stored properly and shows no signs of spoilage (e.g., rancid smell, clumping, discoloration). However, its taste and nutritional value might have degraded.
