L-Rhamnose characterized as a sweet and slightly bitter taste similar to that of D-mannose, which is a typical 6-deoxyhexose. It has been found that sugar chains comprising various monosaccharides have physiological activities. Thus, there have been attempts to utilize these sugar chains as materials for pharmaceuticals and agricultural chemicals. L-Rhamnose or its derivatives are sometimes used as the components of these sugar chains. Also it would be furthermore expected to be available as a material for a reaction flavor since it would under the Maillard reaction with an amino acid to thereby generate a characteristic smell.