I think this is one of those cases where the typical usage is distinct from the technical origin.

> Brewing: to prepare (beer, ale, etc.) by steeping, boiling, and fermentation or by infusion and fermentation

https://www.merriam-webster.com/dictionary/brewing

Kind of like how "flying" travel implicitly includes the part where the airplane is crawling along the tarmac. It would have to be some other context for "taxiing is not flying" to fit as a correction or clarification.

It’s “wort” and since the Vientnamese kegs aren’t pressurized with CO2, they will, in fact, spoil (oxidize) pretty quickly. It won’t kill you but it’ll taste like wet cardboard pretty quickly.