Chemistry Reference
In-Depth Information
For Graham crackers, a reduction of 60% at a dosage of 500 ASNU kg
−
1
flour and 87%
at 1000 ASNU kg
−
1
flour was seen starting from an acrylamide value of 1040 ppb in the
control sample. Further increases in asparaginase dosage up to 5000 ASNU kg
−
1
flour did not
improve acrylamide reduction significantly. The observed reduction level is thus comparable
to that achieved in semisweet biscuits, even though the acrylamide level in the untreated
sample is higher in the Graham crackers, which can, for example, be attributed to higher
asparagine content in whole wheat flour compared to refined flour. In cheese crackers, a 75%
reduction of acrylamide was found at an asparaginase dosage of 500 ASNU kg
−
1
flour. The
control level of 77 ppb acrylamide was low compared to semisweet biscuits and Graham
crackers, which again is caused by ingredient variations in the recipe and differences in
sheeting thickness or in final baking. An enzyme dosage of 500 ASNU kg
−
1
flour resulted
in a maximum effect in these crackers. Higher dosages were tested without improving the
effect.
Acrylamide reductions between 75% and 87% for Graham and cheese crackers confirm the
findings for semisweet biscuits showing reductions up to 90%. Similar results were reported
by Vass
et al
.,
45
who observed acrylamide reductions in wheat crackers of approximately
85% after asparaginase treatment. Amrein
et al
.
25
investigated acrylamide reduction using
asparaginase as a function of enzyme dosage and incubation time in hazelnut biscuits.
Acrylamide reduction of up to 90% was seen in these trials.
4.4.1.2
Pretzels
Asparaginase treatment of cold extruded pretzels was tested at Reading Bakery Systems
(Reading, Pennsylvania, USA). After extrusion, the pretzels were passed through a cooker
with 1% sodium hydroxide before final baking. Results are shown in Fig. 4.6.
250
200
150
100
50
0
0
250
500
1000
2000
ASNU/kg flour
Pretzels produced at Reading Bakery Systems: enzyme dosage was 250-2000 ASNU kg
−1
Fig. 4.6
flour.
