Michała Zalewskiego - V Liceum Ogólnokształcące im. Księcia

Electronic tongue system for the recognition of food samples
1
M.Zalewski
2
M.Wesoły
LO im Księcia Józefa Poniatowskiego, Nowolipie 8,00 – 150 Warsaw, Poland
Email:[email protected]
2Department of Microbioanalytics, Warsaw University of Technology, Noakowskiego 3,00 – 664 Warsaw, Poland
1V
Aim of the project
The main goal of this work was to evaluate the usefulness of the potentiometric electronic tongue for the recognition of brand and storage conditions of soft beverages.
Introduction
Samples
The electronic tongue is a multisensory system dedicated to qualitative and
quantitative analysis of fluid samples. It is composed of cross - selective sensors
and a data analysis system which allows to extract useful information from sensor
responses.
Two different kinds of samples were studied: fizzy drinks (CocaCola and Pepsi)
and beer (Kasztelan). The samples had to be degassed before measuring in order to
obtain reliable results, since the presence of CO2 could disturb the sensor array
signals.
System
Sensor array was composed of ten miniaturized ion-selective electrodes, which were selective for anions and cations, especially for potassium, sodium and calcium
cations. Electrodes responses were analysed by Principal Component Analysis (PCA), what allowed to drew 3D graph which is called the chemical image of sample.
Na+
K+
CS
Ca2+
AS
Ion-exchanger
Ionophore
Plasticizer
Polymer
KTPClPB
KTFPB
KTFPB
KTPClPB
TDMAC
sodium ionophore X
valinomycyn
ETH 129
-
DOS
DOS
DOS
DOS
o - NPOE
PVC
PVC
PVC
PVC
PVC
Results
Coca-Cola® plastic bottle
Coca-Cola® metal can
Coca-Cola® plastic bottle
Coca-Cola® metal can
Pepsi® plastic bottle
Pepsi® metal can
Pepsi® plastic bottle
Pepsi® metal can
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1
1
PC 2
0
4
PC 3
-1
0
0
2
0
-1
4
2
0
-2
1
PC
2
2
0
-1
PC
PC
PC
2
3
2
1
3
1
PC
-1
3
3 -2
0
-2
0
PC 1 2
-2
-4
4
-2
0
PC 1 2
4
Coca-Cola® plastic bottle
Coca-Cola® metal can
Pepsi® plastic bottle
Pepsi® metal can
Beer glass bottle
Beer metal can
Conclusion
2
 Chemical images of soft beverages of various brands formed separate clusters on
1
 Chemical images of beverage samples held in various containers were different.
analysis and classification of soft drinks.
-2
0
-1
PC 2
 The results showed, that potentiometric electronic tongue can be used for the
PC 3
the PCA plot.
0
-1
1
-4
2
0
2
Acknowledgements
This work has been supported by the project “Politechnika dla młodego chemika – staże badawcze uczniów liceum”
-2
1
PC