I check the labels for ingredients in the supermarket baked desserts/breads. Sometimes (not often) I find a gem. There is one pudding they do well and fairly authentically, it’s the panna cota… but be careful which one you buy: they sell at two price points… it’s the more expensive one!
But breads and pastries are mostly VHPF with all sorts of gums, sweeteners, thickeners, preservatives, colorings, flavorings. Now there are a few additives that really help like Citric Acid or gelatin… but when the list of ingredients is longer than my arm, I start to avoid the item. If the ingredient names are long and include a number, well… we’re looking at a HPF or perhaps even a VHPF.
I should add: canning doesn’t buy itself mean that a product is HPF. It merely means that it’s canned to preserve longer. But take a look at the ingredients… and you’ll get the idea!
If any baked goods aren’t stored well… whatever preservatives in them will fail (or not)… it’s Taiwan… you’ll see this. In this case, it’s probably whatever protein was in the cake that’s gone off (egg?).
I once bought a bread from a well known local baker that had lots of egg white in it. Gluten free I think. The vendor didn’t tell me it had to be kept in fridge, it certainly didn’t come to me like that. And… I