Abstract
| Original language | English |
|---|---|
| Pages (from-to) | 1254-1263 |
| Journal | Talanta |
| Volume | 65 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - 2005 |
| MoE publication type | A1 Journal article-refereed |
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Keywords
- on-line measurement
- on-line analysis
- membrane inlet mass spectrometry
- continuous beer fermentation
- matrix effects
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On-line monitoring of continuous beer fermentation process using automatic membrane inlet mass spectrometric system. / Tarkiainen, Virpi; Kotiaho, Tapio; Mattila, Ismo; Virkajärvi, Ilkka; Aristidou, Aristos; Ketola, Raimo (Corresponding Author).
In: Talanta, Vol. 65, No. 5, 2005, p. 1254-1263.Research output: Contribution to journal › Article › Scientific › peer-review
TY - JOUR
T1 - On-line monitoring of continuous beer fermentation process using automatic membrane inlet mass spectrometric system
AU - Tarkiainen, Virpi
AU - Kotiaho, Tapio
AU - Mattila, Ismo
AU - Virkajärvi, Ilkka
AU - Aristidou, Aristos
AU - Ketola, Raimo
PY - 2005
Y1 - 2005
N2 - A fully automatic membrane inlet mass spectrometric (MIMS) on-line instrumentation for the analysis of aroma compounds in continuous beer fermentation processes was constructed and tested. The instrumentation includes automatic filtration of the sample stream, flushing of all tubing between samples and pH control. The calibration standards can be measured periodically. The instrumentation has also an extra sample line that can be used for off-line sample collection or it can be connected to another on-line method. Detection limits for ethanol, acetic acid and eight organic beer aroma compounds were from μg l−1 to low mg l−1 levels and the standard deviations were less than 3.4%. The method has a good repeatability and linearity in the measurement range. Response times are shorter than or equal to 3 min for all compounds except for ethyl caproate, which has a response time of 8 min. In beer aroma compound analysis a good agreement between MIMS and static headspace gas chromatographic (HSGC) measurements was found. The effects of different matrix compounds commonly present in the fermentation media on the MIMS response to acetaldehyde, ethyl acetate and ethanol were studied. Addition of yeast did not have any effect on the MIMS response of ethanol or ethyl acetate. Sugars, glucose and xylose, increased the MIMS response of all studied analytes only slightly, whereas salts, ammonium chloride, ammonium nitrate and sodium chloride, increased the MIMS response of all three studied compounds prominently. The system was used for on-line monitoring of continuous beer fermentation with immobilised yeast. The results show that with MIMS it is possible to monitor the changes in the continuous process as well as delays in the two-phase process.
AB - A fully automatic membrane inlet mass spectrometric (MIMS) on-line instrumentation for the analysis of aroma compounds in continuous beer fermentation processes was constructed and tested. The instrumentation includes automatic filtration of the sample stream, flushing of all tubing between samples and pH control. The calibration standards can be measured periodically. The instrumentation has also an extra sample line that can be used for off-line sample collection or it can be connected to another on-line method. Detection limits for ethanol, acetic acid and eight organic beer aroma compounds were from μg l−1 to low mg l−1 levels and the standard deviations were less than 3.4%. The method has a good repeatability and linearity in the measurement range. Response times are shorter than or equal to 3 min for all compounds except for ethyl caproate, which has a response time of 8 min. In beer aroma compound analysis a good agreement between MIMS and static headspace gas chromatographic (HSGC) measurements was found. The effects of different matrix compounds commonly present in the fermentation media on the MIMS response to acetaldehyde, ethyl acetate and ethanol were studied. Addition of yeast did not have any effect on the MIMS response of ethanol or ethyl acetate. Sugars, glucose and xylose, increased the MIMS response of all studied analytes only slightly, whereas salts, ammonium chloride, ammonium nitrate and sodium chloride, increased the MIMS response of all three studied compounds prominently. The system was used for on-line monitoring of continuous beer fermentation with immobilised yeast. The results show that with MIMS it is possible to monitor the changes in the continuous process as well as delays in the two-phase process.
KW - on-line measurement
KW - on-line analysis
KW - membrane inlet mass spectrometry
KW - continuous beer fermentation
KW - matrix effects
U2 - 10.1016/j.talanta.2004.08.051
DO - 10.1016/j.talanta.2004.08.051
M3 - Article
VL - 65
SP - 1254
EP - 1263
JO - Talanta
JF - Talanta
SN - 0039-9140
IS - 5
ER -