Almost without exception, the available methods for thequantitative determination of individual sugars, in solutionswhere several of them are present together, involve the use of thepolariscope. With sugar solutions of low concentration, the observed rotation may be only a few angular degrees, and resultsbased on such slight differences are far from accurate. Again,highly colored solutions, such as are often obtained from plantmaterial, must be clarified before they can be used in the polariscope and not inconsiderable loss.of sugar by adsorption occursduring the clarification process. Moreover, solutions of plantorigin often contain other optically active substances.
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