Project Number
IWBT-B 08-11
Project title
Bioprocess monitoring of fermentations with infrared spectroscopy
Project leader
Nieuwoudt, H H
Institution
University of Stellenbosch. Faculty of AgriSciences. Institute for Wine Biotechnology
Team members
Nieuwoudt, H H
Du Toit, M
Esbensen, K
Malherbe, S
Jumat, H
Project description
Wine production involves a succession of processes that are catalysed by microbes and it can therefore be considered as a true bioprocess. Real-time monitoring of alcoholic fermentation and malolactic fermentation is of the utmost importance not only due to logistic considerations that include tank space being made available at the earliest opportunity during the harvest season, but also due to the inherent risks of microbial spoilage and problematic fermentations characteristic of each stage. Frequently, timely identifications of problems during each stage of the fermentation can lead to rectification, or at least containment of the impact of the problem through informed decisions that are based on real-time analysis. Malolactic fermentation is a complex biological process catalysed by several lactic acid bacteria. Although monitoring of both alcoholic fermentation and malolactic fermentation are complex processes, malolactic fermentation monitoring can be particularly cumbersome and requires complex chemical analyses, including the quantification of organic acids as well as selected volatile and non-volatile compounds. In enological terms the end-point of malolactic fermentation is marked by that stage of the process where the malic acid concentration falls below ~0.3 g/L. The onset of malolactic fermentation is frequently unpredictable and the progress slow which result in significant variation in the duration from batch to batch. This complicates the simultaneous monitoring of several fermentation vessels and also implies that large numbers of chemical analyses must be done.
Speed is an essential requirement of all the critical stages of process monitoring, including analytical measurements, data processing and data interpretation. This implies that in some instances quantification of the full range of relevant compounds is not an absolute requirement. Nevertheless, quantitative data provide valuable additional information necessary to interpret observed trends during the fermentation process. Real-time process monitoring benefits optimally from a fully automated set-up, however several fundamental aspects, including analytical instrument calibration, optimisation of data processing and establishment of effective data interpretation techniques must first be developed before the strategy can be automated to monitor several fermentation vessels simultaneously.
The aim of this project is to develop the fundamental aspects required for effective alcoholic fermentation and malolactic fermentation monitoring. The strategy described in this proposal combines the use of a rapid analytical technique, Fourier transform near infrared spectroscopy (FTNIR) to generate the instrumental measurements, with chemometric techniques to process and interpret the data. FTNIR is a well established analytical technique for online and at-line monitoring of biotechnological fermentation processes, but its application for monitoring alcoholic fermentation and malolactic during wine production has not been evaluated.
The following aims describe two complementary strategies necessary for the development of the fundamental aspects related to this project. These strategies are: quantification of important fermentation parameters to monitor alcoholic fermentation and malolactic fermentation using FTNIR spectroscopy monitoring the progress of malolactic fermentation through the development of multivariate statistical process control charts based on FTNIR spectroscopy.
Poster(s)
Magerman, C M and Nieuwoudt, H H. 2008. Evaluation of Fourier Transform Infrared (FT-IR) Spectroscopy for the determination of major chemical parameters in fermenting grape must. Poster presentation at the 31st National Congress of the South African Society for Enology and Viticulture. 11-14 November, Somerset West, South Africa.
Magerman, C M, Swanepoel, M and Nieuwoudt, H H. 2009. Going real-time: Infrared spectroscopy R spectroscopy makes a difference to fermentation monitoring. Poster presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa.
Nieuwoudt, H H, Buica, A, Magerman, C M, Moolman, J, Coetzee, L, Oosthuizen, N and Norval, P. 2010. Small and smart: Quantitative analysis in the wine laboratory with FTIR-ATR spectroscopy. Poster presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa
Buica, A, Nieuwoudt, H H and Bauer, F F. 2010. A simple CE method for monitoring organic acids at different stages of the winemaking process. Poster presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa
Hoon, A and Nieuwoudt, H H. 2010. Monitoring grape quality with Fourier transform infrared spectroscopy in an industrial cellar. Poster presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa
Hoon, A and Nieuwoudt, H H. 2010. Quality control of liqueur production using Fourier transform near and mid infrared spectroscopy in and industrial cellar. Poster presented at the 4th International Congress of the South African Society for Enology and Viticulture, 28-30 July, Cape Town, South Africa
Presentation(s)
Swanepoel, M. 2008. Process analytics in winemaking. Paper presented at the 1st Symposium of the South African Chemometrics Society. 1-5 December, Stellenbosch, South Africa.
Swanepoel, M. 2010. Monitoring alcohol and malolactic fermentation online. Paper presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa.
Nieuwoudt, H H. 2010. What is the state of the infrared spectroscopy art in South Africa? Paper presented at the 4th International Congress of the South African Society for Enology and Viticulture. 28-30 July, Cape Town, South Africa.
Nieuwoudt, H H. 2010. Real-time bioprocess monitoring of alcoholic fermentation: Application of Fourier transform infrared (FTIR) spectroscopy. Paper presented at the Cape Biotechnology Forum. 24-26 March 2010, Somerset West, South Africa.
Nieuwoudt, H H, Moolman, J, Coetzee, L, Hoon, A, Oosthuizen, N and Norval, P. 2010. High throughput screening of wine metabolites using Fourier transform infrared spectroscopy in attenuated total reflection mode (FTIR-ATR). Paper presented at the Cape Biotechnology Forum. 24-26 March 2010, Somerset West, South Africa.
Nieuwoudt, H H. 2011. Bioprocess monitoring of alcoholic fermentation using the online NIR infrared spectroscopy. Paper presented at 34th World Congress of Vine and Wine and the 9th General Assembly of the OIV, 20-27 June, Pronto, Portugal.
Nieuwoudt, H H. 2011. Bioprocessing monitoring of alcoholic wine fermentation using online NIR and MIR spectroscopy. Paper presented at the 5th International Conference on Near-Infrared Spectroscopy. 13-20 May 2011. Cape Town, South Africa.
Garlick, J, Du Toit, M and Nieuwoudt, H H. 2012. Bioprocess monitoring and trend identification in wine fermentations with FT-IR spectroscopy and chemometric modelling. Paper presented at MacroWine 2012: 4th International Symposium on Macromolecules and Secondary Metabolites of Grapevine and Wines. 18-21 June, Bordeaux, France.
Article
Louw, L, Roux, K, Tredouw, A, Tomic, O, Naes, T, Nieuwoudt, H H, Van Rensburg, P. 2009. Characterization of selected South African young cultivar wines using FTMIR spectroscopy, gas chromatography, and multivariate data analysis, Journal of Agriculture, Food and Chemistry, Mnth Apr v. 57 (7) (p. 2623-2632)
http://doi.org/10.1021/jf8037456
De Villiers, A, Alberts, P, Tredoux, A G, Nieuwoudt, H H. 2012. Analytical techniques for wine analysis: An African perspective: a review, Analytica Chimica Acta, Mnth Jun v. 730 (p. 2-23)
http://doi.org/10.1016/j.aca.2011.11.064
Thesis
Garlick, J L. 2013. Bioprocess monitoring and chemometric modelling of wine fermentations. MSc. University of Stellenbosch, Stellenbosch.
scholar.sun.ac.za/bitstream/handle/10019…/garlick_bioprocess_2013.pdf?