The shelf life of whey protein powder can be as high as two years if stored correctly. However, the recommended shelf life of whey protein powder is indicated on the product packaging and you should not consume your product once the expiry date has been exceeded. While whey protein powder may still be safe to consume for some time after this date, the protein efficiency is reduced and a fresh product should be acquired.
Protein powder should be kept in an air-tight container in a cool dark location to prolong its shelf life. Moisture is the worst enemy of protein powder and can cause bacteria to grow. Protein powder should not be kept in the fridge or freezer as moisture can form inside your container and spoil your protein powder quickly due to condensation forming inside when opening the container.