Optimisation of fermentation processes is advantaged by using quantitative analysis to provide real-time information. The application of NIR in-line to observe and control fermentation processes was investigated. Determination of biomass, glucose, lactic and acetic acids during fermentations of Staphylococcus xylosus ES13 was performed by a fibre optic probe immersed into the culture broth and connected to a NIR instrument. Mathematical models which related spectra to data from reference assays were constructed. Principal Component Analysis (PCA) and Partial Least Squares Regression (PLSR) of second derivative NIR spectra in the 700-1800 nm region gave satisfactory predictive models for all the parameters of interest. Comparison of spectra collected throughout fermentation runs of S. xylosus ES13, Lactobacillus fermentum ES15 and Streptococcus thermophylus ES17 demonstrated the successful extension of a unique calibration model, developed for S. xylosus ES13, to other strains which were differently shaped but growing in the same medium and fermentation conditions. NIR in-line was so versatile as to measure several biochemical parameters of different bacteria by means of the same models, slightly adapted, so avoiding complete calibration of the instrument for each strain.
Assessment of In-Line Near-Infrared Spectroscopy for Continuous Monitoring of Fermentation Processes
TAMBURINI, Elena;VACCARI, Giuseppe;
2003
Abstract
Optimisation of fermentation processes is advantaged by using quantitative analysis to provide real-time information. The application of NIR in-line to observe and control fermentation processes was investigated. Determination of biomass, glucose, lactic and acetic acids during fermentations of Staphylococcus xylosus ES13 was performed by a fibre optic probe immersed into the culture broth and connected to a NIR instrument. Mathematical models which related spectra to data from reference assays were constructed. Principal Component Analysis (PCA) and Partial Least Squares Regression (PLSR) of second derivative NIR spectra in the 700-1800 nm region gave satisfactory predictive models for all the parameters of interest. Comparison of spectra collected throughout fermentation runs of S. xylosus ES13, Lactobacillus fermentum ES15 and Streptococcus thermophylus ES17 demonstrated the successful extension of a unique calibration model, developed for S. xylosus ES13, to other strains which were differently shaped but growing in the same medium and fermentation conditions. NIR in-line was so versatile as to measure several biochemical parameters of different bacteria by means of the same models, slightly adapted, so avoiding complete calibration of the instrument for each strain.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
