either a batch process or continuous technique may be utilized for the contact method of ordinary adsorbents with adsorbates at 40 u00b0 100 u00b0 c preferably 60 u00b0 80 u00b0 c for instance for batch processing adsorbents in powder form may be added and mixed with beet juice after decoloration the adsorbent is precipitated and isolated or filtered in continuous processes granular adsorbent is filled in a column and beet juice is circulated from the upper or lower portion of the column of the adsorbent layer as for the technique of regenerating the said adsorbents in the second step in the first embodiment of the invention adsorbates can be isolated by circulating or contacting various inorganic salt solutions at 40 u00b0 100 u00b0 c or preferably 60 u00b0 80 u00b0 c followed by the removal of inorganic compounds attached to adsorbents by the use of cool or warm water and again the adsorbents can be used for adsorbing operation the aqueous solutions of inorganic compounds applicable for the present invention may be any solutions containing anions for making ion exchange with adsorbates for which remarkable effects can be obtained by using the salts or compounds containing co 3 2 so 4 2 or hpo 4 2 ions having valence of two accordingly aqueous solutions having at least one compound among carbonates such as sodium carbonate or potassium carbonate sulfates such as sodium sulfate or potassium phosphate and phosphates such as sodium phosphate or potassium phosphate may be effectively utilized by the above operations the colorants produced by ion exchange with inorganic anions of adsorbents can be further put to ion exchange with.