Puff Pastry Test - does butter matter?

So, I was thinking.... which is usually dangerous and usually means I'm obsessing over something random.  This time, however, I was thinking about butter.  Not unusual.

I was about to make more puff pastry to make Apple Turnovers and had to go buy more European butter for the recipe.  Then I thought, how much difference does this fancy butter really make?  Well, I decided to make it my mission to find out.

What's the difference in these butters anyway?  That's a really good question.  Apparently European butter has more fat in it.  So, it has to be better right?  We shall see.

I made two batches of puff pastry, one with Kerrygold Irish butter and one with Store Brand Unsalted Butter.  Everything else was exactly the same.

I baked the pastry two ways:

1) a plain circle cut-out - no sugar, egg wash, nothing
2) as an apple turnover with apple filling and egg wash

CA was generous enough to help me do the taste test.  He really suffers for me.

• Visually, neither of us saw any difference.  Both versions puffed equally well and browned equally well.

• Texturally, we didn't see any differences either.  They were both equally light and flaky in texture.

• Taste, yep, this is where there were some differences.  We both agreed that the flavor was better in the European version of the plain circle but we detected no difference in the Apple Turnover.  Putting the filling in there added enough other flavors that we couldn't tell the difference between the European and Regular versions.  I actually think the difference I tasted was due to salt and not the butter itself.  The European butter did have salt in it and the Regular butter did not.

That said, I think in the future I'll use regular butter if I'm making something with a lot of other components and use European butter for more simple dishes.

Of course, now I'm really curious if I could tell the difference if I used Salted Regular Butter.  I may suffer through that experiment for you all, but only if you're nice.

Julie