Mountain States Oilseeds is Kosher Certified and sells food grade yellow mustard seed in bulk, bags, totes and containers. With a grower base of 200, Mountain States Oilseeds can supply your needs in brown, oriental, and yellow mustard as well as safflower and flax. MSO operates a storage and cleaning facility. The cleaning facility uses a Cimbre Delta cleaner, Oliver gravity table and a large bank of spirals. MSO tracks all of its products from the farmer to you.