I found this recipe on the google.
The stalk must be cut above the tubers immediately before the plant flowers to retain all of the sugar in the stalk; the stalk is then ground in a hammermill to release the sugars from the central cylinder, the pith, the ligneous cells, and to a small amount from the bark; the sugar juices from the hammermill are collected; the remaining mass of the central cylinder, pith, ligneous cells and bark is squeezed to remove the remaining sugar juices; the entire collected sugar juice is then processed by 1) bringing the pH to 4.0-4.5, 2) heating to 80°-82° F., 3) adding yeast, 4) fermenting for approximately 24 hours. The method produces the maximum quantity of high grade ethanol per acre of plant of any known plant source, permitting the leaves to be used to return a high nitrogen content of the soil, the ground stalk mass to provide protein as an animal food, and the tubers to provide human or animal foods. The method for the first time uses the entire Jerusalem Artichoke while providing the maximum amount of ethanol as a worldwide energy source by the least costly, least complicated, and most energy efficient process.
This sounds quite promising. I will have to grow a patch next year for the stalks. Instead of a hammer mill I will use my usual method of milling in the mulcher and pressing with the cider press. There is no mention of the SG but something equal to beer, or better, would be good.
