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Biotechnol. J. 2008, 3, 1355–1367

plays a strong supporting role for research at the IWBT and has established itself as a research focus in its own right.The first non-routine application of FTIR at the IWBT was to establish a calibration for the analysis of glycerol in wine [57, 58]. This ana- lytical tool was used to conduct an industry-wide survey of the glycerol levels in premium South African wines and to test the hypothesis that the glycerol concentration in this category wine is pos- itively linked to quality [57, 58]. FTIR spectroscopy is also a valuable tool in the IWBT yeast biotech- nology programme by speeding up the screening of fermentation profiles of desirable variants within a population of wine yeast strains and to evaluate wine yeasts that have been genetically modified. FTIR spectroscopy established for quantitative analysis in wine is also now optimised for monitor- ing grape quality during ripening, yeast and must during alcoholic fermentation and bacteria causing MLF. Rapid detection of spoilage and the identifi- cation of wine-associated bacteria using FTIR- coupled attenuated total reflectance (ATR) is con- ducted with the long-term aim of establishing spectral libraries for future research projects. Fourier transform mid-infrared (FTMIR) spec- troscopy has also been used to establish fermenta- tion profiles of yeast strains developed in a classi- cal breeding programme for the enhanced produc- tion of glycerol [59]. FTMIR spectroscopy is firmly established in the IWBT as an analytical tool for evaluation of the volatile fermentation profiles of yeasts during breeding and fermentation. FTMIR spectroscopy has also been optimised for monitor- ing quality control parameters (sugar content, pH and titratable acidity) during grape ripening [60] and the current focus is on bioprocess monitoring including both alcoholic fermentation and MLF. The IWBT has recently acquired an near infrared (NIR) spectrometer, which has expanded the ma- trix that can be analysed to include not only liquids, but also semi-solids and solids. These latter appli- cations currently include the development of quan- titative calibrations on anthocyanin content in grape-skin homogenates and quality parameters of whole grape berries (such as browning potential). Future research applications include cell wall bio- spectroscopy focused on grape berry ripening processes, plant-pathogen interactions and yeast mannoprotein production.

To investigate and correlate the large amount of data generated using these spectroscopic ap- proaches with established chemical reference methods requires advanced statistical support.The extraction and interpretation of the relevant ‘un- derlying’ information in analytical datasets re- quires extensive application of chemometric tech-

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niques. Modern instrumentation are frequently es- tablished with customized software packages that includes multivariate quantification, classification and cluster analysis tools [61, 62]. The modern trend to apply chemometric techniques to analyti- cal and instrumental signals has opened up the possibility in biotechnology to establish algorithms that can be used for investigating trends, monitor- ing bioprocesses and for the prediction of future outcomes related to biological processes as well as chemical and sensory profiles. The IWBT is at the forefront of these initiatives with active interna- tional collaborators including industrial and aca- demic research partners to support the develop- ment of spectroscopic and chemometric tools in the South African wine environment. The IWBT has also been instrumental in establishing the South African Chemometrics Society (SACS) with the as- sistance of local academics and international chemometric experts.Thus the IWBT plans to con- tinue to be at the forefront of initiatives to integrate wine science research in South Africa into a coher- ent framework through the sustained development of the necessary instrumentation, statistical soft- ware tools and expert supported training of indus- try and academic stakeholders.



SunBio is an exciting new venture that presents an opportunity to realise the commercial potential of the IWBTs research activities by establishing a spin-off company from Stellenbosch University. SunBio aims to establish a sustainable product de- velopment process that will combine the research output and intellectual property generated by the IWBT with sound commercialisation practices.The company will focus on the areas of genetic en- hancement technologies, conventional develop- ment of unique yeast and bacterial strains, and de- velopment of niche service offerings (chemical and microbiological support) to the wine industry. Sun- Bio was initiated by funding obtained from Cape Biotech Trust, a Biotechnology Innovation Centre (BIC) established by the South African Department of Science and Technology.

SunBio research projects are designed to gener- ate a large number of hybrid and/or recombinant wine yeast strains. For some projects this will in- volve the development of gene expression cas- settes and yeast strains that are able to enrich wines with antioxidants, and nutritional supple- ments geared toward the health and wellness mar- ket segment. SunBio, also aims to make the fer- mentation process more efficient through the pro-


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