NA Beer

[Voggy01]

I want to brew a really good NA IPA for my pregnant wife (we have not found a good hoppy NA beer to purchase). After doing some research, I have confirmed that it is as simple as I expected. Brew beer, ferment, cook off alcohol which boils at 173-ish. Articles have said 30 min should be sufficient. But as the healthy development of my child is at stake, I would like to have reliable verification.
Question: how can I reliably confirm that I have removed most of the alcohol? Will a gravity measurement be accurate? In theory, the new, post alcohol cook-off, FG would be very close to the OG. Correct?

 

[VikeMan]

In theory, the new, post alcohol cook-off, FG would be very close to the OG. Correct?

No, it would be higher than with alcohol, but lower than the OG, because there are a lot less sugars than there were before fermentation.