Prof Paul Andrew Kilmartin
Professor Kilmartin's research background combines wine science projects for the NZ wine industry, and the development of active packing. As a result, Paul has a strong interest in making use of active by-products from the grape industry and further active extracts, to test our their biocidal properties, and incorporate these into materials with commercial applications.
My main areas of research are fairly evenly divided between wine chemistry and applications of conducting polymers with the Biocide Toolbox programme and the Polymer Electronics Research Centre, currently involving 7 PhD and 2 MSc/BSc(hons) projects and several international visitors. My main scientific training is in the area of Electrochemistry, coupled with the use of a range of Chromatographic, Spectroscopic and Surface Analysis techniques.
(A) Conducting polymers as chemical sensing elements. PEDOT and polyanilines are used as redox mediators for the determination of antioxidants in beverages, including polyphenols, ascorbic acid and SO2 in wines, grape juices, teas and milk. This work includes including collaborations with Dr Alexander Turke and Prof Wolf-Joachim Fischer of the Technical University of Dresden, a PhD project on the MBIE High Performance Sensors programme, and applications of voltammetric methods to monitoring patient disease status (with Dr Anthony Phillips of SBS).
(B) Conducting polymers as antioxidants. The antioxidant properties of conducting polymers has been investigated for several years after the discovery of this property at Auckland. This work provided a research theme within the ‘Hybrid Polymers’ MBIE programme, with a strong commercialisation focus, and has included the successful development of antioxidant and antimicrobial polyaniline/polyethylene blends. Further projects involve antifouling coatings for the marine industry.
(C) Grape tannins for biocidal applications including smart packaging. The antimicrobial and antioxidant properties of grape tannins extracted from winery waste are being investigated within the current 'Biocide Toolbox’ MBIE programme. Tannin structures are also being investigated using solid state NMR, FTIR and various chromatographic methods, and involves a collaboration with the team of Dr Andrea Versari at the University of Bologna, Italy.
(D) Sauvignon blanc harvesting methods. This research centres around an Auckland discovery that more intense varietal aromas are produced with machine harvesting versus hand-picking of grapes, coupled with effects of juice oxidation that can be regulated with sulfite additions at harvest. The timing of antioxidant additions are being investigated, along with novel grape maceration and pressing procedures (with Villa Maria, Constellation, and Delegats wineries). The research involves a collaboration with Assoc Prof Wessel Du Toit of the University of Stellenbosch, South Africa.
(E) Sauvignon blanc and Pinot Gris aroma profiles. The chemical aroma composition of both Sauvignon blanc and more recently Pinot Gris are being surveyed, to identify distinctive aroma compound profiles for New Zealand wines. Aroma modelling involving sensory panel outputs is being developed. Aroma stability is also being examined in relation to polyphenol oxidation, including novel electrochemical approaches, while storage temperature has been identified as being of overriding importance for Marlborough Sauvignon blanc.