1. Field of the Invention
The present invention relates to a method for separating fructose from a mixture of sugars, wherein certain solid adsorbents are used as separating media.
2. Description of the Prior Art
Fructose is the sweetest of all the sugars present in nature and has been known to be useful dietetically as the most ideal sugar. However, no economical method available of manufacturing fructose has been made available at present. Fructose, consequently, has been an expensive commodity and has found only limited use as a high-grade sweetener.
Various methods have been investigated and proposed for the individual separation of glucose and fructose from mixtures containing sugars.
Examples of these methods are: (1 ) separating fructose from glucose by converting fructose into a calcium-fructose complex by treatment with calcium hydroxide or calcium chloride; (2) effecting the desired separation by using a cation-exchange resin bed such as the calcium form (U.S. Pat. No. 3,044,904), the strontium form (U.S. Pat. No. 3,044,905), the silver form (U.S. Pat. No. 3,044,906) and the hydrazine form (U.S. Pat. No. 3,471,329); (3) effecting the desired separation by using anion-exchange resin beds such as the borate form (U.S. Pat. No. 2,818,851) and the bisulfite form (U.S. Pat. No. 3,806,363); (4) and other sophisticated methods (U.S. Pat. No. 3,050,444 ).
Among the methods proposed to date, the calcium method has been adopted for commercial operation and the bisulfite anion-exchange resin method is claimed to be promising. Nevertheless, the former method is batchwise in nature and not totally economical for large scale production, and the latter method requires a large amount of resin and is confronted with the serious problem of resin deterioration.
An object of this invention is to provide an economical method for separating fructose from a mixture of sugars containing fructose and glucose.
Other objects and characteristic features of this invention will become apparent from the further description appearing hereinafter.