Preparing home made mass gainer the night before

[notthestone]

Hello, I make myself a mass gainer which contains water, oats, honey, PB, olive oil, banana and whey. Adds up to about 1900 calories which I split into 2.

I usually make it every morning before work which makes it difficult time-wise.

Do you think this shake can be preserved in the fridge for 18 hours? (if I make it the night before I'll eat it around 12-15pm the day after)
I don't see any faults, just making sure.

If not, which ingredient is the problematic one so I'll add it in the morning

Thanks

[SuffolkPunch]

Whey can taste bad if you mix it too far in advance. I guess you could put it in the freezer after mixing and take it out in the morning. Or leave the whey out until later.

[Mrpb]

Yeah whey may be problematic, the rest is probably fine.

[notthestone]

Yeah the other ingredients are pretty common and simple so I wasn't worried about those,

Asked mostly for the whey since I assumed it had specific "rules".