Abstract: A method and device for use in connection with a dough divider machine which continuously uses mineral oil for lubrication. The method comprises capturing mineral oil, flour, and dough contaminants which becomes mixed as the dough divider operates and filtering the captured mixture so that substantially pure mineral oil is separated from the flour, dough and contaminates. The substantially pure mineral oil is then injected back into the dough divider machine for lubrication. By comparing lost mineral oil to the weight of bakery products produced during a predetermined period, the amount of mineral oil in the bakery products is determined. The filtration method and device utilize a gravity filtration diffuser coalesence and precipitation and a suction filtration. The device is portable for use with either one or more dough divider machines and for cleaning.