Because I use mustard for my own consumption only occasionally, I am buying smallest available packages (350 g) but after opening I can see unused mustard slowly changing into "water" and solid component. I understand that every food deteriorates but I would like to understand something more about this.

  • Why it does not deteriorate this way in unopened package?
  • Is there some advice to slow down the process? Or even a way to simply renew its original consistence?

2 Answers 2


Mustard often separates, it doesn't mean it's going bad. It's likely perfectly fine, mustard stays good for years in the refrigerator. Just stir it up before using it to recombine.

As for why it doesn't separate unopened, sometimes it does. Often you are buying a product that's been manufactured recently, so it hasn't had time to separate yet.

  • The vinegar content is a great preservative. Commented May 11, 2018 at 21:29
  • 2
    Syneresis, just as in yogurt: freepatentsonline.com/6461657.html Give the stuff a stir or shake. It'll be fine. Commented May 13, 2018 at 23:20
  • Thanks for the answer and the suggestion works great. @WayfaringStranger - thanks for the term.
    – miroxlav
    Commented May 14, 2018 at 8:16
  • 1
    @WayfaringStranger, that's a good word, nerd.
    – GdD
    Commented May 14, 2018 at 8:29
  • @GdD It shocks people who think they're absorbing positive Chi energy from their blueberry Greek yogurt! Commented May 14, 2018 at 21:54

You could go to a restaurant that uses single-serve packets (a fast-food place like McDonalds or a Chinese/Asian restaurant, any place doing takeaway food) and request that the manager/assistant manager sell you a sufficient small quanity of those packets

  • 2
    The question was why does it separate...
    – Stephie
    Commented May 12, 2018 at 16:08
  • @Stephie Yes, it was! I can read! I provided a suggested solution to not 'buying smallest available packages (350 g)' apparently available to her Most everyone knows that many products separate and are intelligent enough to not have to read 'Shake before using' on a label One would think that detailed scientic replies in explanation are NOT solutions to your perceived problems
    – Cynetta
    Commented May 13, 2018 at 16:54
  • @Stephie – I find this answer to be creative and adding an idea to my mindset so as the OP I upvoted it. I also sometimes have access to cash-and-carry companies where restaurants purchase their ingredients so this answer also reminded me about going this way.
    – miroxlav
    Commented May 14, 2018 at 8:20

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.