A fixing agent in the form of an oil/water type, lamellar emulsion or suspension in which the aqueous phase is the principal component, the aqueous phase containing water and a byproduct of agriculture or fermentation and the oil phase containing oil and emulsifiers. The emulsion or suspension is prepared by adding an aqueous solution to the oil phase in order to produce a water/oil type emulsion or suspension, by adding a portion of the aqueous phase in order to produce an inverse oil/water type emulsion or suspension, and by thereafter mixing the oil/water type emulsion or suspension with the remainder of the aqueous phase.