Buttermilk substitute in baking?

[Life is Good]

My favourite chocolate mudcake recipe calls for buttermilk. Not a lot - just enough to make me buy a huge carton (because that is the only way it comes here), use 1/5 of it and then let it sit in the fridge until it has little buttermilk babies of its own!

I am so over wasting and am just not game to use old buttermilk in what I regard as a relatively expensive cake to make (and potentially ruin!).

I am really not convinced about using milk with a bit of lemon or vinegar added (though I stand advised if you ladies have had success with it).

I am wondering if I could just use Greek yoghurt or sour cream? I imagine these would be a closer substitute? Again, what do you all think?

Do you think I could freeze the buttermilk into portions? Can you freeze buttermilk?

TIA

[Olive]

not sure about using other things, id just use the vinegar recipe, ive done that before without any issues

[Astrid]

You can freeze buttermilk. I have some frozen, but am yet to see if it works the same when defrosted.

[~Kim~]

I know Christy uses a combination of ricemilk and tofu blended together....probably not what you're after but there are alternatives.
And yes milk freezes well just takes ages to thaw.

[Rouge]

You can also make your own buttermilk with milk and vinegar or lemon juice. But like Astrid says I freeze my buttermilk in ziplock bags in 125ml lots.

[AnyDream]

Perfect excuse for buttermilk pancakes on the weekend!

I have used milk and vinegar in the past - works fine.

[spooky]

As already stated, buttermilk makes amazing pancakes/pikelets - whick also freeze well.

[Cricket]

I've never frozen buttermilk, so can't help you on that one.
I've used low fat sour cream or plain yohurt as a substitute before with excellent results.
You can also get powdered buttermilk, I think. I've never tried it myself, but my MIL uses it. That would prevent waste - you could just reconstitute the amount you need, and the rest would keep without issues. But, like I said, I haven't tried it myself.
All the best!

[entreat]

I usually do some kind of sour cream & milk mix. Never tried the vinegar option... sounds a bit too chem-class for my liking!

[Life is Good]

Thank you for all of your suggestions. I am making a mudcake this week and plan to use the milk / vinegar combo. Failing that I will try the frozen buttermilk option.

I like to think that I am fairly "well-versed" in the kitchen, but the buttermilk pancakes that I made a couple of months back made me feel like I should be banned from all things cooking! They were TERRIBLE - like little rubber door stops! So yeah - until I work out how to make good ones, pancakes aren't really an option

[Traveller]

I read the title as "Breastmilk Substitute in baking" and was going to suggest using cows milk

Ahem, sorry not much help am I? As you were...

[entreat]

to get the best light & fluffy pancakes, separate the eggs, mix the yolks in as per normal, but with the white - whip them until soft peaks form, then fold them into the batter at the end. OMG... so simple, and the result is amazing! Hasn't failed me yet!