At the top of a +1G(gauge) loop the wing will have an AoA of zero, which it will probably maintain* until it gets to the 270degree point (ie pointing vertically downwards).
PDR
* That's not necessarily guaranteed as there are lots of other factors that come into play in this, but at the top of a +1G(gauge) loop the aeroplane is in a zero-G state, and other factors notwithstanding the path from there to the 270degree point is ballistic rather than aerodynamic. The wing only needs to do work again for the recovery from the vertical dive to S&L flight.