Food Chemistry

4.2 Monosaccharides 259

Table 4.9.Taste threshold values of sugars in water

Sugar Recognition threshold Detection threshold

mol/l% mol/l%

Fructose 0. 052 0. 94 0. 02 0. 24
Glucose 0. 090 1. 63 0. 065 1. 17
Lactose 0. 116 4. 19 0. 072 2. 60
Maltose 0. 080 2. 89 0. 038 1. 36
Saccharose 0. 024 0. 81 0. 011 0. 36

ness values. Only mean values are given with
deviations omitted. The recognition threshold
values for saccharose cited in the literature vary
from 0.01 to 0.037 mol/l.
Taste quality and intensity are dependent not
only on a compound’s structure but on other
taste reception parameters: temperature, pH and
the presence of additional sweet or non-sweet
compounds.
The temperature dependence of the taste in-
tensity is especially pronounced in the case of
D-fructose (Fig. 4.4). It is based on the varying
intensity of sweetness of the different isomers:

Table 4.10.Relative sweetness of sugars and sugar alcohols to sucrosea

Sugar/ Relative Sugar/ Relative
sugar alcohol sweetness sugar alcohol sweetness

Saccharose 100 D-Mannitol 69
Galactitol 41 D-Mannose 59
D-Fructose 114 Raffinose 22
D-Galactose 63 D-Rhamnose 33
D-Glucose 69 D-Sorbitol 51
Invert sugar 95 Xylitol 102
Lactose 39 D-Xylose 67
Maltose 46
a10% aqueous solution.

Table 4.11.Concentration (%) of iso-sweet aqueous solutions of sugars and sugar alcohols

D-Fructose D-Glucose Lactose Saccharose D-Sorbitol Xylitol

0. 
   
   
   
   81. 
       
       
       
       83. 
           
           
           
           51. 
               
           
           
           
           
       
       
       
       
   
   
   
   


1. 
   
   
   
   73. 
       
       
       
       66. 
           
           
           
           52. 
               
           
           
           
           
       
       
       
       
   
   
   
   


2. 
   
   
   
   28. 
       
       
       
       315. 
            
            
            
            75. 
                
                
                
                9. 
                   
                   
                   
                   38. 5
                   
                   
                   
                   
                
                
                
                
            
            
            
            
       
       
       
       
   
   
   
   


3. 
   
   
   
   613. 
        
        
        
        925. 
             
             
             
             910. 
                  
                  
                  
                  17. 
                      
                      
                      
                      29. 8
                      
                      
                      
                      
                  
                  
                  
                  
             
             
             
             
        
        
        
        
   
   
   
   


4. 
   
   
   
   20. 
       
       
       
       34. 
           
           
           
           615. 
                
           
           
           
           
       
       
       
       
   
   
   
   


5. 
   
   
   
   127. 
        
        
        
        820. 
             
             
             
             28. 
                 
                 
                 
                 218. 5
                 
                 
                 
                 
             
             
             
             
        
        
        
        
   
   
   
   


6. 
   
   
   
   30. 
       
       
       
       25. 4
       
       
       
       
   
   
   
   


7. 
   
   
   
   240. 
        
        
        
        48. 8
        
        
        
        
   
   
   
   

Fig. 4.4.Temperature dependence of the relative sweet-

ness of some sugars (based on saccharose100 at each

temperature; —D-fructose, – – –D-glucose,–·–·–

D-galactose, –··–··– maltose) (according toShallen-

bergerandBirch, 1975)

β-D-fructopyranose is the sweetest isomer, and

its concentration decreases as the temperature

increases (Fig. 4.5).