Honestly, the part about it feeling like "betraying a trust" really got me. I just see it totally different. To me, sharing that recipe with more people is a way to honor your great aunt, not betray her. The stories you have don't get stripped away because someone else knows the flour amounts. They just get to taste something real. Keeping it totally secret means the recipe and the memory could actually die with the family. Letting others bake it spreads that bit of her further.

Doubt you need lab grade stuff for this. Sounds like the kind of test where you drip some vinegar on a scale flake and call it a day. Probably uses pH strips from a pool kit or some citric acid powder. If your boiler was that critical, you wouldn't be getting advice from a forum post.

But how much flavor are we actually losing by skipping that step?