Nothing particularly wrong with "works by," however silly it may sound. There are better ways to express the same sentiment; specifically, one could replace "works by" with "is achieved through":
Borgarnes water also has a particularly high surface tension, which the brand explains is achieved through "inhibiting evaporation of the volatiles that want to escape quickly —the aromas, the bouquet."
Let's make it even more readable:
According to the manufacturer, in addition to [whatever they were bragging about earlier], Borgarnes water has a high surface tension achieved through inhibiting evaporation of the aromas that constitute the bouquet.