Healthy Living on June 16, 2010 by

What the hull?

Impact Huller: Photo courtesy of

Impact Huller: Photo courtesy of

Please excuse my play on words, I couldn’t resist. For the last few months, I’ve had the privilege of spending a few hours a week working with Bob on a labeling project. During these talks, we inevitably talk about more than just labeling. Last week we got onto a very interesting topic- the process of hulling and why some grains are more work than others to hull.

The hull is the tough outer layer of a grain- this is outside the bran layer. Think corn husk on a smaller scale. All true grains (those that come from a grass species) have a hull. Some, such as modern wheat, have easily removable husks and can be hulled by simply shaking the kernel out of the hull by hand. Others, such as oats, barley and spelt have tough hulls that take a little more encouraging.

That said, I began to wonder how do they remove the hull? Bob told me all about it. Forgive me if I didn’t get all of the technical specs covered. The hull is removed in a machine called an Impact Huller (see photo at left). Grain enters the hulling chamber and the impeller wheel throws the grains against agitators (really, really fast). This impact removes the hull, which is then removed by vacuum pumps.  This process happens very quickly and produces grains that are intact, but removed from their hull. Bob said it’s one of the loudest machines he’s heard and makes little popping noises as grains slam into the walls.

I thought it was very interesting. I hope you did too.

Add Your Comment

Your email address will not be published. Required fields are marked *

Latest Posts

Keep up to date on the latest from
Bob's Red Mill
Subscribe Now