Earlier quoted context omitted.
Nope. American milk is pasteurized to a much higher temp. It lasts way longer. Irish goes off in days, US milk will last a month in the fridge. The extra pasteurization effects the taste and flavor.
I can't find any evidence to support that. High-Temperature, Short-Time (HSTS) Pasteurization appears to be the standard in both Ireland [1] and the US [2] -- 71.7°C / 161°F for 15 seconds. And I can tell you from personal experience that US milk goes bad in days as well, and has for decades. I don't know where you're getting the idea that it lasts a month in the fridge. There are real differences in some foods betwe…
I did find that US allows the use of hormones to increase milk production. Possibly that's a factor? But very difficult to tell.