Transcript Formation of hydroxymethyl-furfural and hydroxymethylfuroic acid in

Formation of hydroxymethyl-furfural
and hydroxymethylfuroic acid in foods
Graz University of Technology
Institute of Biochemistry
Functional Food Group
M. Murkovic
EUROPEAN
COMMISSION
FOOD QUALITY AND SAFETY
Food and Chemical Toxicology 46 (2008) 3697–3702
Furane derivatives in roasted foods
Furfural
5-Methylfurfural
Furfurylalkohol
2-Methyl-3-oxo-THF
2-Furanmethanolacetate
Roasting temperature:
220 °C
Furane
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
Erich Leitner, TU Graz
Proposed mechanism of
thermal generation of glucose,
levoglucosan, and
fructofuranosyl cation,
showing percent contribution
of glucose and fructose
moieties to HMF formation at
350 °C and 65 °C
Perez-Locas, Yaylayan, 2008
Formation of HMF from C3 units
O
OH
Isomerization
OH
glycerol-aldehyde
O
OH
OH
glycerolaldehyde
OH
O
OH
O
OH
-H2O
OH
methyl-glyoxal
O
+
O
OH
methylglyoxal
-2 H2O
HO
O
O
HMF
Cämmerer et al., 2009
H
O
H
O
HO
O
O
O
CH2
H
H
OH
H
H
OH
H
C OH
H2
O
O
OH
C OH
H2
H2C
O
OH
OH
H
O
HO
N
O
HMFFormation
R
CH2
CH2
O
RNH2
O
O
C OH
H2
didesoxy-triketo
H2C
OH
N
R
Acid catalyzed formation of HMF
HMF with different acids, 254 nm
OH
OH
HO OH
OH
14
Fructose
H+/-3H2O
HO
O
O
HMF
Concentration ( ug/ml)
O
12
NaH2PO4
10
Citric acid
Without
8
Fumaric acid
6
Tartaric acid
Maleic acid
4
Acetic acid
2
Oxalic acid
0
0
1
2
3
4
5
Time (h)
Model system: 0.1 M amino acid + carbohydrate
Chromatogram of HMF
RP, 280 nm
UV-Absorption
Coffee
Dryed fruit
Standard
0
1
2
3
4
Retention time (min)
5
6
Formation of HMF in apple juice
(90 °C)
28
HMF (µg/mL)
26
24
22
20
18
16
14
0
50
100
150
Heating time (min)
200
Foods with a high content of HMF (1)
Apricot
HMF
(mg/kg)
n
30, 780
2 Date
HMF
(mg/kg)
n
1000
1
1
1
Pear
100
1 Fig
Peach
40
1 Pineapple
280
1
Plum
1600, 2200
2 Apple
80
1
Plum jam
1100, 1200
2 Fruit bread
450
1
Coffee (roasted, ground)
300 - 1900
22
Foods with a high content of HMF (2)
HMF (mg/L)
n
Sherry
2 – 320
3
Port
40 – 60
5
Balsamico
190 – 3400
9
White wine
0.3 - 4
35
Formation of HMF in Madeira-wine
HMF in wine (µg/mL)
700
600
sweet
half-sweet
dry
extra-dry
500
400
300
200
100
0
0
2
4
6
8
10
12
Storage time (years)
14
16
Formation kinetics of HMF and
HMFA in arabica and robusta coffee
HMF and HMFA [µg/g]
900
HMFA in arabica
HMF in robusta
HMFA in robusta
HMF in arabica
200
150
100
50
0
0
2
4
6
8
Roasting time [min]
10
Formation of HMF and HMFA in
coffee and the model system
HMF and HMFA [Mol%]
3,0
HMFA
HMF
2,5
2,0
1,5
1,0
0,5
0,0
arab
i ca
mod
el-a
robu
rabi
ca
st a
mod
el-ro
bus
ta
Proposed mechanism of HMFA
formation in model systems
HO
O
C
HO
C O
CH3
O
CH2
HO
C
C O
CH
CH
HO CH
O
aldolcondensation
(-H2O)
HO
HC
HO CH
HO
CH2
OH
O
ketalisation
(-H2O)
O
Formation of HMF and HMFA
during roasting of coffee
HMF [µg/g]
160
500
140
400
120
100
300
80
200
60
high
HMF
HMFA
medium
180
low
600
200
HMFA [µg/g]
700
40
100
0
20
0
0
2
4
6
Roasting time [min]
8
10
Industrial roasting
HMF and HMF [mmol/mol]
30
20
equimolar mixtures
glyceraldehyde
40
methylglyoxal
pyruvate
methylglyoxal
pyruvate
glyceraldehyde + pyruvate
10
methylglyoxal
glyceraldehyde
Formation of HMF and HMFA
in model systems
HMF
HMFA
0
pure substances
Co-workers
• Kristina Bagdonaite
• Draxl Sigrid
• Derler Karin
• Maria Bornik
• Pichler Nicole
• Daniela Jöbstl
• Alam Zeb
• H. Günther – Kraft Foods Bremen