Barley is the main staple grain of Tibet where it forms a large part of the local culture. The reasons for this are pretty much the same as for northern scandinavia. The fact that the Chinese eat mostly wheat and rice makes the eating of barley in Tibet a very important and unique cultural trait in the region.

There is six row barley and two row barley. The wild type is 6 row and in the two row barley the other 4 rows still exist but are sterile meaning you only get 2 rows of seeds on a ear. Because ⅔ of the planned seeds don't come to fruit the last ⅓ gets extra energy from the plants meaning these seeds become larger. These larger seeds are excellent for beer brewing which is why malt barley is typically from a 2-row variety. The 6 row types are mainly used for animal feed and for bread flour.

You don't have to grind barley to eat it. After barley is dehulled you get pot barley also called Pearl barley. This is a great filler in stew. You can also boil it like rice.

While wheat is very sensitive to salt, barley is much hardier to it. Archeological evidence shows that in ancient mesopotamia the amount of barley grown increased over time which has been interpreted, in combination with other findings, as evidence that these lands suffered from an accumulation of salt, making the growing of wheat impossible.

Malt from barley is not only used for beer. You can also use it to make a sweetener called barley malt syrup. You can also ferment malt to make malt vinegar, a staple in British cuisine.

The enzymes in barley malt are so strong it's enough to not only convert its own starch to sugars, it can convert around 8-10 times more than its own content in starch. Traditionally vodka was made from potatoes but because potatoes lack the amylase enzyme needed you also always had to add substantial amounts of malt to convert the potato starch to sugar that can be fermented to make alcohol. This way you can make alcohol from almost any starch as long as you also add some barley malt to the mash.

When making beer the hull is beneficial because if you use a hullless grain the mash becomes a big sloppy mass that doesn't really drain well, like a super wet dough. The hull however breaks up this structure and makes the mash free draining meaning you can easily remove the liquids from the solids. Even beer like wheat beer is often still up to 50% barley because of this. Funnily enough the original mesopotamian beer was not strained at all. All the solids were still in there so it was chunky. They drank this beer with a straw.

Regarding how barley flour for bread was traditionally made. When you grind up whole barley the inner portion turns to flour while the hull tends to come out the other side pretty much intact because it's quite tough. Therefore you can sift it through a sieve because while it is thin the hull takes up a lot of space in the other 2 dimensions. The house wives of old in barley dominant regions would do this near daily. While this works well it's of course extra work compared to a hullless grain like wheat where the flour that goes out of the grain mill is ready to use straight from the get go. Of course nowadays we have industrial equipment that can dehull tonnes of barley per second.

And their safety tests focused on how the chemical interacts with human biochemical pathways. They didn't test how it affects the various gut flora and fauna we depend on. And I'm wondering if it has anything to do with the increased frequency of IBS (though there's a lot of potential vectors for that, microplastics being another).

Ah yeah that's pretty shitty