The Foundations of Chemistry

Figure 28-11 Formation of

sucrose by the condensation of

an 
-glucose molecule with a

-fructose molecule.

H

HO C

HO C

C

C C

H

H

H

O

H

OH

CH 2 OH

3

OH

4

6

5 2

1

H H

OH H

OH

O

HOH 2 C OH

C

C

C

C

CH 2 OH

5

43

2

1

6

H

HO C

HO C

C

C C

H

H

H

O

H

CH 2 OH

OH^1

H H

OH H

OH

O

HOH 2 C

C

C

C

C

CH 2 OH

2

O

α-glucose

β-fructose sucrose

• H 2 O

+ H 2 O

+ H 2 O

H

HO C

HO C

C

C C

H

H

H

O

H

O

CH 2 OH

OH

(^1) H
C
HO C
C
C C
H
H
H
O
H
OH
CH 2 OH
OH
4
α
α
HO
H C
HO C
C
C C
H
H
H
O
H O
CH 2 OH
OH^1
H
C
HO C
C
C C
H
OH
H
O
H
H
CH 2 OH
OH
β^4 β
lactose ( -form)β
maltose ( -form)α
TABLE 28-5 Sweetness of Common Sugars Relative to
Sucrose
Sweetness Relative
Substance to Sucrose at 1.00
lactose (milk sugar, a disaccharide) 0.16
galactose (a monosaccharide in milk sugar) 0.32
maltose (a disaccharide used in beer making) 0.33
glucose (dextrose, a common monosaccharide) 0.74
sucrose (table sugar, a disaccharide) 1.00
fructose (fruit sugar, a monosaccharide) 1.74
Figure 28-12 Two disaccharides:
maltose and lacrose. Each involves
two glucose units. Maltose has

-1,4-linkage and lactose has a
-1,4-linkage.