A bit of Iowa clay (not any clay, but one that has just the right "something" in it) and a bit of lard tossed into the vats of sorghum sirup mills on Iowa farms have modified an old process in the making of sorghum that is resulting in clear golden sirup which is fully the equal of the product of the best commercial factories.
Gaessler, W. G.; Reid, J. David; and Cuthbert, F. L.
Farm Science Reporter: Vol. 1
, Article 6.
Available at: http://lib.dr.iastate.edu/farmsciencereporter/vol1/iss3/6