advantageously the particles of powder will be in the range of from about 1 to about 50 microns while the amount of powder for a given amount of water will vary widely it is preferred that the powder be from about 2 to about 15 w v advantageously the liquid suspending medium may be water or an aqueous solution for example an acid or a base to achieve a specific ph the suspended powdered substrate is then dyed with an edible natural dye for example curcumin turmeric or an anthocyanin such as those contained in commercial grape skin extract the dye may be added directly to the liquid in which the powder is suspended or may be first placed in a solvent to form a dye solution which is then added to the suspended powder typically the solvent will be water but other solvents such as for example methyl alcohol or ethyl alcohol may be used advantageously an agent is employed to fix the dye onto the powder exemplary of these against are metal salts such as sodium chloride aluminum chloride and aluminum sulfate inorganic acids such as for example hydrochloric acid may also be employed except in the case of the inorganic acids the fixing agent may be in an amount equal to form about 0 1 to about 10 by weight of the powder in.