Well, on german packaging, the word is “ultrahocherhitzt”, translating to “heated ultra high”, which is self-explanatory.

To what temperature do they heat the milk?

It’s really really really double secret probation pasteurized.

What I can’t figure out is why does it taste better? My organic ultra-pasteurized skim milk tastes creamier than the regular pasteurized stuff.

Ultra-pasteurized is a hotter temperature and shorter time. Kills off more varieties of bacteria.

It’s common in a lot of tropical countries with a shortage of refrigeration, sold in tetrahedron shaped containers.

Sure, it’s a rapid heating process over a short period of time which can delay spoilage, and render milk shelf stable in the right packaging. What’s the problem?