PS: The date on the packaging is the "Optimum Taste Date."

另：包装上的日期是“最佳饮用期”。

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But soda past its expiration date goes flat and loses much of its taste.

但是过期的苏打水跑气，味道也会大打折扣。

《柯林斯英汉双解大词典》

The “use-by” or “best if used-by” date indicates the last day that the item is at its best quality as far as taste, texture, appearance, odor, and nutritional value. The decline after that is gradual.

“有效使用期”或“最好于该日期前使用”表示的是该产品在这个日期前，从口感、质地、外观、气味和营养价值等各方面保质着最佳质量，过期之后质量就会逐渐下降。

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