... prerequisite for successful
food analysis. The broad selection of cleanup and
enrichment techniques takes into account the many
matrices and compound classes under study.
Sample preparation for HPLC ... automatically.
62
5
Characteristics of
a good sample
introduction device
Figure 46
A typical 6- port
injection valve
After the sample has been prepared for introduction
onto th...
... 1000 0.9
Furazolidone 4.54 A 16. 0 96 16. 024 16. 028 992 984 1.3
Pyrazon 13.72 A 19.024 18.987 19.000 1000 1000 1.7
N-Acetylsulfapyidine 14 .66 A 23.307 23.282 23.282 9 76 1000 1.1
Ethopabat *up 13.40 ... is a well-established
technique for food analysis, LC/MS is only now emerging as
a useful tool in this area. A GC-based analysis is appropriate
only for those food compounds th...
... . 76
Gradient formation at high pressure . . . . . . . . . . . . . . . 77
Gradient formation at low pressure . . . . . . . . . . . . . . . 77
VII
Part Two
The Equipment Basics
HPLC
for Food
Analysis
A ... used for various purposes in modern food processing.
For example, citric acid adds a fresh, acidic flavor, whereas
succinic acid gives food a more salty, bitter taste. In
ad...
... amperometry
Chromographic conditions for electrochemical detection
The HPLC method presented here was used for the
analysis of iodide in table salt.
17
34
HPLC method performance
Limit of detection
for ECD 40 µg/l
Repeatability ... refractive index
HPLC method performance
Limit of detection
for ECD 50 µg/l with S/N = 2
Repeatability of
RT over 10 runs < 0.3 %
areas over 10...
... have set maximum
tolerance levels for these compounds in foodstuffs. HPLC is
now preferred for the analysis of amines in food matrices
because of its shorter analysis time and relatively simple
sample ... software
components needed
for successful HPLC,
and an introduction to
the analytical techniques
that have become
routine in food analysis
Part Two
Chromatographic con...
... perform
according to food analytical requirements. The former has a
single dual-piston mechanism for low-pressure gradient
formation, whereas the latter has a double dual-piston
mechanism for ... gradient
formation), and that designed for flow rates between 0.05
and 5 ml/min (high-pressure gradient formation).
In separating the multiple constituents of a typical food
sample, HPLC...
... they are used prima-
rily in the analysis of carbohydrates and nonaromatic acids.
104
<- [M + NH
4
]
+
Abundance
100000
80000
60 000
20000
40000
60 3
63 9
987
400 60 0
1000
800
m/z
Figure 74
Mass ... provide for automated drawing of the baselines
during postrun replotting and for the plotting of calibration
curves showing detector response. For unattended analyses
in which seve...