Chemistry Reference
In-Depth Information
NH
NH
N
(+) N
CH
2
OH
CH
2
OH
CH
2
OH
CH
2
OH
OH
OH
O
OH
O
OH
O
O
OH
OH
O
OH
OH
H
H
OH
OH
OH
OH
OH
S (-)
S (-)
NH
NH
(+) N
N
CH
2
OH
CH
2
OH
R
OH
OH
O
O
O
R
O
OH
OH
H
H
OH
OH
S (-)
SH
Figure 4.1
Proposed mechanism of the
trans
-galactosylation reaction by
β
-galactosidase.
5
oH-r represents a lactose or (galacto)-oligosaccharide of variable chain length.
Vivinal
®
GOS is a commercially available GOS (FrieslandCampina Domo,
Zwolle, the Netherlands). The saccharides in Vivinal
GOS vary in chain length
from disaccharides (DP2) to octasaccharides (DP8). The type of linkage between
the monomer units is mainly 1→4 Gal (55 percent in the trisaccharide fraction and
72 percent in the higher oligosaccharide fraction). 1→6 Gal linkages occur 3 to 4
percent. Other linkages including 1→2 Glc, 1→3 Glc, 1→4 Glc, 1→6 Glc, 1→2 Gal,
and 1→3 Gal can also be present.
8-10
4.4 APPlICATIoNs
GOS have a safe history of use in food and infant nutrition and are applied in
various kinds of products. Products containing GOS were first launched in Japan in
the late 1980s. The first GOS-containing product in Europe was launched in 1997
with a Dutch fermented milk product. The use of GOS is increasing gradually in
various applications worldwide. Because of their high solubility and stability (e.g.,
