The travel bursary funded attendance at the XVII International Botrytis Symposium, held in Santa Cruz, Chile. The bursary recipient was an invited keynote speaker at this symposium. The keynote lecture covered aspects of Wine Australia research project CSU 1301 and dealt with the use of ATR FTIR and GC MS techniques for Botrytis cinerea detection and evaluation.
In addition to the keynote presentation, a further oral presentation on laccase gene expression during the infection of grape berries by Botrytis cinerea was delivered. Several areas of research collaboration were discussed with international colleagues working on Botrytis. Selected highlights from the symposium presentations are discussed in this report. Knowledge gained as a result of the symposium attendance and associated study tour will be incorporated into current and planned research activities. Wine education packages delivered by Charles Sturt University will be updated to reflect the latest knowledge on Botrytis biology and management.
Ee Lin Tek presented an oral presentation titled 'Formation and regulation of wine yeast biofilms (mats) in nitrogen-limiting conditions' at the 14th International Congress on Yeasts in Awaji Island, Japan. EL Tek also presented a poster with the same title. Participating in the conference broadened EL’s knowledge on the wide applications of yeast on fermentation technology and the current yeast research interests, breakthroughs and issues.
While in Japan, EL made a visit to the research laboratories A/Prof Tatsuya Maeda at the Institute of Molecular and Cellular Biosciences, The University of Tokyo. His research focuses on nitrogen-responsive signalling pathway in yeast. This travel also enabled network establishment.
The purpose of this report is to summarise the outcomes of a Wine Australia travel grant. Additional funding support was provided by the Australian Research Council Centre of Excellence in Plant Energy Biology.
The main activities that were supported by this grant were participation in two international conferences and one national conference. At these meetings, data were presented that describe the genetic mapping and functional characterisation of genes involved in sodium exclusion in grapevine rootstocks. These data have been generated from a collaborative project between CSIRO Agriculture and the University of Adelaide. The participation in these meetings allowed for useful discussions and novel experimental ideas to be gained, which will assist the future development of this project and publication of our data. Highlights from the meetings are discussed, and any additional formats that were used to disseminate research findings are also mentioned.
At the time of publication, carrageenans are not permitted additives in wine although they are approved for food use. An outcome of this research is that the Winemakers’ Federation of Australia (WFA) has submitted an application to Food Standards Australia New Zealand (FSANZ) seeking to amend Food Standards Code – Standard 4.5.1 to approve the use of pectin/carrageenan in commercial Australian winemaking.
The China Wine Barometer provides a time-series tracking of the attitudes, perceptions and behaviours of multiple samples of Chinese wine consumers, who are socio-demographically representative in terms of age, gender and income of the upper-middle class urban population aged 18-49, who drink imported wine at least twice a year. Data were collected twice a year over the three-year period 2013-2015. The time-series nature of the project, combined with state-of-the-art marketing research techniques equips Wine Australia and its levy payers with the knowledge to make smarter marketing choices, so that they can grow their brands, and assist them in decision-making and strategic development in the Chinese wine market.
An AGWA travel award enabled the attendance of Dr Michelle Walker at the 14th International Congress on Yeasts held at Awaji Yumebutai, Hyogo Prefecture in Japan (11-15 September 2016). This congress, held every four years, attracted some 440 academic and industry delegates from about 40 countries, and included several reputable international speakers. The conference explored different yeast(s) and their genetics, synthetic biology and their application in the production of alcoholic beverages, and biotechnology (biofuel/high value products). The conference provided opportunities to meet informally with other researchers in related areas of yeast research. Student participation was actively encouraged through sponsorship by the conference organisers and The Carl Singer Foundation. Students awarded scholarships gave short talks (as well as poster presentations) on their research.
An oral presentation (and poster) entitled ‘Mapping of genes responsible for yeast-derived modulation of colour in model red wine’ was given. A visit was undertaken to the research laboratories of Professor Hiroshiri Takagi (Nara Institute of Science and Technology). His research on how proline protects yeast from alcoholic stress during fermentation is of particular interest, as improved use of this nitrogen source in juice has been a long standing interest of our group.
The award of this travel grant provided University of Adelaide postdoctoral research fellow Lukas Danner the opportunity to attend and present at Seventh European Conference on Sensory and Consumer Research, Eurosense 2016 and visit leading research laboratories and meet researchers from INRA (French National Institute for Agricultural Research) and AgroTechParis.
Lukas Danner presented research findings from the Wine Australia funded research project (UA1203) at the conference in form of an oral presentation titled ‘Relationships between wine consumers’ fine wine behaviour and their moods, product-evoked emotions, liking and willingness to pay for Australian Shiraz wine: A segmentation study’. A poster was also presented.
Accentuated Cut Edges (ACE) maceration reduces skin particle size thereby increasing the rate of extraction of components from grape skins. Subsequently, the wine can be pressed earlier (PE) than usual, and the fermentation completed in a smaller tank to make PE-ACE wine. The technique optimises fruit characteristics and saves time, space and labour in the winery. ACE maceration was tested on five red wine grape varieties at six commercial wineries located in four Australian states. PEACE treated wines had similar phenolic composition and sensory scores to the untreated wines. ACE maceration has the potential to significantly improve processing efficiency, profitability and competitiveness in the global market.
The results of a five-year field experiment in the South Australian Riverland indicated that under non-restricted irrigation allocations there were no water use savings or improvements in rootzone salinity with the use of subsurface irrigation; either using conventional subsurface drip line or when the subsurface drip line was enclosed in a porous fabric strip designed to improve the lateral movement of water. Only under severely reduced irrigation volume was there some yield advantage with the two types of subsurface irrigation. There was deposition of fine colloidal clay within the fabric covering which may have influenced the long-term performance of this irrigation system with the water source used in this experiment and this warrants further investigation.
There is growing interest from winemakers in being able to produce wines with lower ethanol content that do not have compromised aroma, flavour, and mouth-feel. There are opportunities across the value chain to implement strategies to achieve this, including viticultural practices, pre-fermentation and winemaking practices, microbiological strategies and post-fermentation practices and processing technologies (Varela et al. 2015).
However, the application of yeast strains that produce less ethanol during fermentation remains a simple and cheap strategy for producers to adopt towards this goal. Unfortunately, all available commercial S. cerevisiae wine yeasts are very similar in terms of ethanol yield; a difference of 0.5% v/v has been observed between ‘high’ and ‘low’ ethanol producers (Palacios et al. 2007; Varela et al. 2008). In order to reduce ethanol concentration, novel yeast need to be isolated or generated.