A homemade cake is minimally processed. The flour and sugar are processed but nothing that heavily alters it.
A commercial cake on the other hand has stabilizers, ph balancers, etc.
You're over thinking it. Almost nothing made at home is ultra processed unless you're doing some weird sausage making. If you can name the ingredients easily, it probably isn't ultra processed.
I think the GP's point is there is no meaningful nutritional difference between a from-scratch cake and a box cake. Both are pretty unhealthy and should be eaten only as special treats. "Ultra-processed" is not a useful way of separating healthy from unhealthy foods.
That is precisely the point that should be discussed because, from what I've read, UPFs are much worse than plain fatty or sugary food cooked by human hands.
The extra stuff in UPFs interacts with your body in ways that you are not prepared for and some of them are designed to make you consume more. The first example that comes to mind is the sodium added to make you tolerate more sugar.
They may not differ much in terms of calories or nutrients, but there absolutely is a difference - the ultra processed cake has preservatives and additives that are way harder on your gut microbiome, which affects your body's ability to process other food.
A homemade cake is minimally processed. The flour and sugar are processed but nothing that heavily alters it.
A commercial cake on the other hand has stabilizers, ph balancers, etc.
You're over thinking it. Almost nothing made at home is ultra processed unless you're doing some weird sausage making. If you can name the ingredients easily, it probably isn't ultra processed.