Blowoff source: oats or yeast?

[BrewDey]

The last 2 batches have provided my only 2 blowoffs to date. I'm curious to know if this is due to the yeast itself, or to my grain bill. Both brews (Jamil's Oatmeal Stout; L'il Sparky's Nut Brown) included 1 lb. of oats, and I'd imagine they add a lot of proteins that could lead to 'explosions'.

But since it's been warm, I've used Coopers yeast since it is apparently tollerant of higher temps. So they have that ingredient in common as well...any ideas?

 

[Orfy]

Could be one, two or three of those things.

The only way to know for sure is to change one thing at a time.