GNC的label上是best before date 不是expiry date. 搜了一下 best before date的含义
So, what is the “Best Before Date” of a food item?
The “Best Before Date” is, according to the manufacturer, the last date by which a products flavor or quality is best, the optimal time of its shelf life for quality. As noted above, the product may still be enjoyed after the “best before date.” Additionally the manufacturer may call this the “Best if Used By” date or the “Best By” date, which indicates that the quality of food might diminish after that date, but it is still good to eat and the shelf life is still active.