A method of preparing smoke-impregnated tubular casings is described. The process comprises: (a) providing a tubular casing having interior and exterior surfaces, the tubular casing being selected from cellulose fiber tubular casings and synthetic tubular casings, and the tubular casing being suitable for encasing food fillings having a form selected from one of liquid and paste; (b) applying to the interior surface of the tubular casing a mixture comprising, (i) liquid smoke, (ii) browning agents, and (iii) optionally water; (c) allowing the mixture to remain in contact with the interior surface of the tubular casing for at least 5 days; and (d) optionally shirring and watering the mixture treated casing. The smoke-impregnated tubular casings prepared in accordance with the method of the present invention are suitable for liquid or paste-like food fillings, such as sausage meat emulsions.