Having just harvested a gallon or so of dock seeds today I was hoping to find an answer to removing the papery hull here. In a way, you guys had that answer for me.
While the papery hull is not inedible, it really has little nutritive value. I've eaten dock seed as a sort of wild trail side granola. If one likes munching on
newspaper or cardboard, this might be for you. It has never been for me. I will be testing making a porridge with the hulls on just for completeness sake. However my main goal is to make a flour. In my research I found that at some point during the colonial period, dock was grown as a
staple grain. I can't imagine that a staple with hulls on would have been widely accepted. In addition the little nutritive value in the hulls is dietary fiber.
Since I am interested in this grain as a survival food the fiber content is quite pertinent. A body that is not used to a high fiber content will find itself moving its bowels quickly and easily. Dietary fiber sort of uncoils in the bowel, providing bulk and lubrication. While it may provide a sense of fullness, it soon turns to diarrhea. That in turn leads to dehydration. One simply needs an efficient way to get the papery hulls off.
I took a sample of the grain and ran it through a Weston seed mill (cast metal burr type, cheap and maybe not even worth the trip to get it more on that later) set loosely, ie coarse grind. This came from a suggestion from a fellow at The Country Living mill. The result was marginal. The hulls seemed to be separated to some degree but not at all satisfactory. I arrived at
the answer by way of the suggestion to burn them off. Couple that with the knowledge that all grain is harvested at a point when it has a certain moisture content. Mix in some thoughts about moisture content in
wood pellet combustion. The answer lay in the moisture content.
I tried two methods. Both worked admirably and can be replicated in the field.
Method one: Microwave the seeds on high for about 2 minutes. 1 minute was not quite enough. This leaves the hulls bone dry.
Method two: Oven broiler (electric) - Using a
cast iron skillet (I am certain a cake pan or a cookie sheet will work fine also) spread the grain in a single layer and place under the broiler on the highest rack. Every minute or so pull the
skillet out and stir the grain. After about 5 minute (sorry I didn't time it) the hulls
should be very dry.
Final steps, both methods: take a tablespoon full of grain into the palm of one hand. Use the other to "grind" the grain in your palms. The hulls disintegrate to a powder! From there it is simple winnowing. It took 3 passes in front of a weak fan (about as strong as a computer muffin fan). I pal ground the grain one more time and gave it a final pass in front of the fan.
I next intend to try drying the hulls in the oven on very low heat, perhaps 175°F. [Edit: 2 hours at 170°F proved enough drying tie for excellent results] I don't want to liberate oils, just dry the hulls. Another idea I want to try is making a dehulling mill using rubber sheeting such as gasket material found in the plumbing department. Thus replacing and saving my palms.
I hope this helps everyone.