358
.~.~..~...~..... .~~...~........~~~~....~..
/ Oxidative
cleavage
rCOOH I
DAIRY CHEMISTRY AND BIOCHEMISTRY
t
- Addition compound
I
- N-substituted glycosylamine
3a. Schiff base
3b. Enol form
(Galactose) (Glucose) > Fructosylysh <
H 0’ OCH3 II
0
Pvrldoslne
J
HC -OH
HC -OH
HZC -OH
I
I
Ervthroluc
&id
OR
RI C-CH-NH I
11 /
W2)4
I
NH
I
y+2
CGQH
Carboxymethvl
BROWNING
Figure 9.8 Initial steps of the Maillard reaction with the formation of furosine (after hydrolysis
with 7.8 M HCI) as well as of N-E-carboxymethyl lysine and erythronic acid (from Erbersdobler
and Dehn-Muller, 1989).