Location: Sustainable Biofuels and Co-Products
Title: Removal and isolation of germ-rich fractions from hull-less barley using a fitzpatrick comminuting mill Authors
Submitted to: Cereal Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 25, 2013
Publication Date: November 21, 2013
Citation: Moreau, R.A., Hicks, K.B. 2013. Removal and isolation of germ-rich fractions from hull-less barley using a fitzpatrick comminuting mill. Cereal Chemistry. 90:546-551. Interpretive Summary: Barley kernels only contain about 2 percent oil but much of the oil is concentrated in the germ or embryo portion of the barley. Because wheat germ and wheat germ oil are known to be healthy food products, we sought to develop a process to produce barley germ. We developed a process to produce barley germ using a Fitzpatrick Comminuting Mill and sieving. Using this process we produced a germ-enriched fraction that contained up to 15 percent oil, which is comparable to the amount of oil that we have previously reported in hand-dissected barley germ and slightly higher than the amount of oil in commercial wheat germ. The barley germ enriched fractions and the barley oil that can be extracted from them may have value as nutraceutical or premium edible oils.
Technical Abstract: A process was developed to produce a germ-enriched fraction from hull-less barley using a Fitzpatrick Comminuting Mill followed by sieving. Hulled and hull-less barleys contain 1.5-2.5% oil and, like wheat kernels which contain wheat germ oil, much of the oil in barley kernels is in the germ fraction. A process, which combined FitzMilling and sieving, produced a germ-enriched fraction, with an oil content of about 15% and a yield of about 1.1%. This is higher than the levels of oil in most samples of commercial wheat germ. Experimental conditions were also described to produce a germ enriched fraction with a higher yield (2.16%), but it would have a lower oil content (10.24%). Germination and compositional analysis studies suggested that FitzMilling hull-less barley for 2 minutes or longer reduced germination rates to 1% or less, which was interpreted to mean that almost all of the viable germ was removed. In contrast, FitzMilling conventional hulled barley for 4 minutes had no effect on germination, and milling for 6-8 minutes resulted in germination rates of 36 and 12%, respectively. These germ enriched fractions and the extracted oil they contain may have value as nutraceuticals or premium edible oils.