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- Söderström, Charlotte, 1973-, et al.
(författare)
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Use of an electronic tongue and HPLC with electrochemical detection to differentiate molds in culture media
- 2005
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Ingår i: International Journal of Food Microbiology. - 0168-1605 .- 1879-3460. ; 97:3, s. 247-257
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Tidskriftsartikel (refereegranskat)abstract
- A study was conducted to further evaluate an electronic tongue, using high-performance liquid chromatography (HPLC) with electrochemical (EC) and UV detection as a reference method. The electronic tongue consisted of four working electrodes made of different metals and arranged in a standard three-electrode configuration. Pulses of voltage were applied to the metals, and the current responses were sampled and collected in a data matrix. The objectives of the present investigation were to examine the ability of the electronic tongue to distinguish between two mold species growing in three different media, and to obtain support for the hypothesis that the device actually discriminates between different redox-active metabolites produced by the molds. Peak areas in EC and UV HPLC chromatograms were collected in a data matrix. The electronic tongue data and the EC and UV data were then subjected to principal component analysis (PCA). A number of peaks in the HPLC-EC chromatograms indicated that the growth media contained redox-active metabolites. Moreover, PCA of peak areas in EC chromatograms revealed differences between the distribution of redox-active metabolites produced by the two species and between the three culture media. The same pattern was apparent in a PCA score plot of electronic tongue data. The peaks in the UV and EC chromatograms differed, and these were also shown by the PCA score plots.
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| 2. |
- Söderström, Charlotte, et al.
(författare)
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Use of an electronic tongue to analyze mold growth in liquid media
- 2003
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Ingår i: International Journal of Food Microbiology. - 0168-1605 .- 1879-3460. ; 83:3, s. 253-261
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Tidskriftsartikel (refereegranskat)abstract
- The feasibility of employing an electronic tongue to measure the growth of mold in a liquid medium was studied. We used the electronic tongue developed at Linköping University, which is based on pulsed voltammetry and consists of an array of different metal electrodes. Instead of focusing on a single parameter, this device provides information about the condition or quality of a sample or process. Accordingly, the data obtained are complex, and multivariate methods such as principal component analysis (PCA) or projection to latent structures (PLS) are required to extract relevant information. A gas chromatographic technique was developed to measure ergosterol content in mold biomass and was subsequently used as a reference method to investigate the ability of the electronic tongue to measure the growth of mold in liquid media. The result shows that the electronic tongue can monitor mold growth in liquids. In PLS analysis, the electronic tongue signals correlate well with the amount of ergosterol in the mold biomass as well as the microbially induced changes in the pH of the medium. © 2002 Elsevier Science B.V. All rights reserved.
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| 3. |
- Le Guyader, Francoise S, et al.
(författare)
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Detection of noroviruses in raspberries associated with a gastroenteritis outbreak
- 2004
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Ingår i: International Journal of Food Microbiology. - : Elsevier BV. - 0168-1605 .- 1879-3460. ; 97:2, s. 179-186
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Tidskriftsartikel (refereegranskat)abstract
- Following an acute foodborne gastroenteritis outbreak in southern Sweden, stool specimens from five of nine ill patients were found positive for norovirus using reverse transcriptase polymerase chain reaction. Epidemiological data pointed to raspberry cakes as the source of the outbreak. Using a combination of generic and patient-specific primers and novel food analysis methodology (with extraction efficiency control and inhibitor removal), norovirus strains from two different genogroups were directly identified in the contaminated raspberries.
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