You find a half-used tub at the back of the cupboard and the date has passed. Is it still fine? Whey powder is low in moisture and lasts a long time, but the date on the label is not something to ignore.
Expiry vs best before
Many protein tubs carry a best before date, which refers to quality such as taste, mixing and nutrient accuracy. A tub a few weeks past that date, stored well, may still be fine. A tub that has been open for a long time in a humid kitchen is a different story.
Signs your whey has gone bad
- Sour, rancid or stale smell. Fresh whey smells mild and milky or like its flavour.
- Hard clumps or lumps that do not break with a spoon, which suggest moisture got in.
- Any mould, spots or discolouration.
- Bitter or off taste even after mixing.
- Foul smell after mixing, or stomach cramps after drinking.
If you notice any of these, throw the tub away. Do not try to rescue it.
What affects shelf life
| Factor | Effect |
|---|---|
| Humidity | Biggest risk. Moisture causes clumps and spoilage. |
| Heat | Speeds up flavour and quality loss. |
| Wet scoop | Introduces moisture into the tub. |
| Open lid | Air and humidity enter the powder. |
How to store whey properly
- Keep it in a cool, dry cupboard, away from the stove and sunlight.
- Close the lid tightly after every use.
- Use a dry scoop and keep the scoop outside the powder, or in a clean zip bag.
- Do not keep the tub in the fridge, since condensation can add moisture.
More tips are in our guide on storing protein powder in humid weather.
FAQs
Is it dangerous to drink expired whey? If it smells and looks normal and is only slightly past its best-before date, the main change is usually quality. If it shows spoilage signs, it can upset your stomach, so discard it.
Can I cook with old whey? Heat does not make a spoiled product safe. Only use powder that smells and looks normal.
How can I tell the date on my tub? Check the base or lid for the manufacturing and best-before or expiry date, and plan to finish the tub within a few months of opening it.
