“Commercially, selenium is produced as a byproduct in the refining of these ores, most often during copper production.” - Note that 50 microgramms of Selenium per day are plenty, so maybe that is not the best example.
Potassium Gluconate…a bit too complicated for me to describe.
I’m gonna name Potassium Chloride instead, even though only some of us use that. I get about half my Potassium from that, and half from Potassium Gluconate, at this point.
Potassium Chloride = http://en.wikipedia.org/wiki/Sylvite , a naturally occuring mineral.
My fiber source, powdered psyllium husks, are the seeds of a plant, dried and powdered.
Maltodextrin: water and a starch (corn or wheat) are mixed, some bacteria are added, the whole thing gets cooked.
Whey is a byproduct of making cheese.
Those (without Selenium) are the expensive parts of (my) Soylent, they come to about 90% of the cost.
Most of them require little to none processing, as shown, but I think the real reason it ends up cheaper (and more sustainable, especially in remote/hot/third world locations) is that unlike food none of these ingredients have to be cooled, and every single one can safely be stored for at least a year.
Some of the micronutrients, especially some vitamins, are probably more complicated and expensive to produce, but at least financially speaking their cost is insignificant.