I have made matcha (bubble tea powder + cream) in bulk and mixed with water and sugar, stored it in a large container and put it in the refrigerator. In couple of days the content become jelly-like, and had green deposit at the bottom.

Is there any way to prevent gelatination?

I'm not really bothered by the green deposit at the bottom.

I have tried adding some preservative (potassium sorbate, sodium benzoate, citric acid) but with no luck.

  • Hi, I am not sure I understand the question. Did you buy straight matcha powder from a shop and store it in the fridge, or did you create some other powder with matcha taste and store that, as a intermediate step in making bubble tea? If it is the second, you would have to add the recipe.
    – rumtscho
    Jun 6, 2021 at 15:56
  • Per Rumtscho, "matcha" is powdered green tea, and has no gelatinizing agents in in. So what was it that you actually made?
    – FuzzyChef
    Jun 6, 2021 at 18:53
  • Hopefully not slime mould :\
    – Tetsujin
    Jun 8, 2021 at 8:49
  • Voting to close because the question does not supply enough information to be answered.
    – FuzzyChef
    Jun 8, 2021 at 23:47
  • 1
    I'm afraid this is becoming even more confusing. Currently, it seems that you either used matcha, or you used bubble tea powder. We still cannot tell what it was - to me, it seems more likely that you used bubble tea powder, but we already got an answer assuming that you used matcha. You also said it was "a couple of days" but you don't say if it was below or above 5 days (the safety cutoff for food in the refrigerator). It's not clear if you used bubble tea powder that contains powdered cream from the manufacturer, if you added cream to bubble tea powder, or if you added cream to matcha.
    – rumtscho
    Jun 9, 2021 at 14:11

1 Answer 1


If you mix matcha powder with cream, sugar and water, you have created a substance that will make some microbes very happy. For that mix, the same rule as for other "prepared foods" apply: No longer safe after two or three days in the refrigerator.

What you are seeing is one or multiple of the following:

  • Green Deposit: Powder sinking to the bottom - when you mix, it's not dissolved, but just particles suspended in the remaining liquid.
  • Gelatinization caused by:
    • Milk/cream curdling (if you added citric or another acid, that will promote curdling)
    • Microbiological growth

In short, I would not recommend this kind of shortcut for more than two days. You have seen already that it doesn't work the way you planned. Freezing would at least stop bacterial growth, but depending on the ingredients (e.g. sugar content) the mix may not freeze too well and remain slushy.

  • Kudos on taking a stab at a very confusing question
    – FuzzyChef
    Jun 9, 2021 at 16:29
  • 1
    @FuzzyChef the kind of powder is secondary - just water, cream and sugar in the fridge is good for a very limited time only. The mysterious powder (which I kind of read as matcha = ground up green tea) will not make it better.
    – Stephie
    Jun 9, 2021 at 16:31
  • yeah, and presumably if it's some kind of matcha + tapioca, that would be even worse.
    – FuzzyChef
    Jun 9, 2021 at 16:33
  • A quick web search shows “boba mixes” containing matcha, creamer and sugar. Instructions are to mix that up with water and ice cubes. Seems quite similar to the OP’s description.
    – Stephie
    Jun 9, 2021 at 16:40
  • @Stephie yeah that's one of name, so many names & terms
    – Andikac
    Jun 9, 2021 at 18:19

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