Definitely time to clean & sterilize, methinks Re: Is this what your kefir jar looks like? Time to clean?

That looks like some type of mold or fungus to me.

(btw, if anyone wants to see the picture 'smaller' so you can see the entire picture, you can right-click and choose 'view image').

I've never seen anything 'greenish' in my kefir -- nothing but creamy white or yellow (the yellow is when the milk/butter fat turns to butter).

And I don't recall ever reading of making kefirs without a lid (to keep out the various critters in the air). Some ferments/cultures are done without lids in order to capture the critters in the air to be part of the culture (that's how sourdough and vinegars 'happen' without 'starters').

Personally, I wouldn't ingest kefir that had anything that looks like that in it - and I'd wash and sterilize the jar before I used it again.

Blessings,

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