Can cashew milk go bad, and how do you tell?
Yes, it can go bad.

The date on the package is one indication, but it may be a "best by"  date and does not guarantee the milk will go bad by then. It doesn't necessarily mean it is guaranteed safe, either, although most stores will give you a refund on product that spoils early.

Look for the following signs (written for almond milk, but cashew milk follows the same rules):


  
  the container seems abnormally bloated after opening  
  mold is present  
  any funky or pungent odors  
  the product has curdled or is visibly thick and slimy (observe the consistency when putting)  
  a change in color, as almond milk may appear more yellow when it has spoiled
  


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