I’ve never ate one but in the 70s I went to a seminar on making alcohol to power our cars and Jerusalem Artichokes were being touted as one of the highest alcohol per acre crops available.
The starch in Jerusalem Artichokes is the same thing you will find in those probiotic capsules at the pharmacy costing $30 for a months worth. The amount of inulin, that human indigestible starch, in a single tuber of of a couple of ounces is more than that months worth of gut bacteria food in those capsules.