My cuz is. Quite a commonly known aspect of big brewing nowadays. Not by all of course. Certain breweries, for sure! The reason Coopers has plastered all over there labels, "preservative/additive free"
These conglomerates aren't about to tell you these facts. Why some beers give you a headache after only a few & others you can drink all night.
Sorry if I offended. Was just a headsup as I'm over these breweries.......