Could you tell us a bit about yourself and your academic background?

I am originally from the Gansu Province in North-Western China. As an undergraduate student doing a bachelor’s degree in Nanjing University of Aeronautics and Astronautics (with a major in applied chemistry), I have always wanted to pursue further study abroad. I had heard from a friend that there was a unique major available here at the University of Adelaide and I was really interested in food and wine, which was entirely new and unknown to me. I thought that I would come over and give it a try to uncover the mysteries of wine!

While I was here for my Masters in Viticulture and Oenology in 2017, I was actually surrounded by students of the previous Training Centre- I was really impressed by their enthusiastic and hard working attitudes. After my supervisor told me about positions available in the new Training Centre, I did some further investigations online and applied. I’ve always been interested in working in this area and exploring what happens during winemaking, as it is such a complex and unpredictable process. I thought that this was an opportunity that would allow me to pursue my interest in tasting and researching wine.

For the research component of my master’s program, I did a project on apple pulp waste (apple pomace left over after juice pressing for spirit production or distilling) initiated by the Hills Cider Company, extracting the fermentable sugars and double distilling it to make spirit (apple brandy). The pilot scale treatment was carried out here in the laboratory, and with treatments of acid hydrolysis and autoclaving, I was able to produce spirits at last, but it was not practical or cost effective for commercial scale production. I also worked on a project in partnership with Potatoes SA after graduation, which utilised potato peel and starch waste on a laboratory scale to make vodka. Similar to the apple brandy, this was done through enzymatic treatment on gelatinised raw potato material, alcohol fermentation then double distillation. The project was able to be scaled up and several batches of vodka have been made successfully with the Adelaide Hill Distillery. Through these projects, I was exposed to research that was alcohol based, and after discovering this type of topic, I decided I would like to turn back to wine and that I wanted to know more about wine science.

Earlier this year, I had experience in a 2018 vintage at Grant Burge Wine, in the Barossa Valley as a Vintage Weight Bridge Assessor. As they are specialised in white and sparkling white wine, it mostly involved processing white and sparkling wine based on site- which sparked an interest for me in improving the approach of winemakers to refining wine, as well as giving me more experience on my current project from an industry point of view. I am very happy to uncover more about the process of winemaking, and I personally love white, bubbles, sparkling wines, and anything related to them.

 

Could you introduce us to your project and what it involves?

My project is partnered with VA Filtration (a company specialising in membrane filtration technology) and involves the use of membrane filtration as an alternative to bentonite fining in wine processing. We are looking at protein stability in white wine, which is a big problem in the industry (especially for storage of bottled wines), as protein deposits can form in the wine either as a precipitate or cloudiness present in the wine.

These properties are unattractive to consumers, and traditionally, bentonite is used to remove these proteins and ensure the wine is stable before it is released to the market. However, the use of bentonite fining can strip the wine of beneficial aromas and flavours and result in loss of saleable wine volume. Additionally, bentonite cannot be reused and is an ongoing cost to the winemakers. The downgraded wine, recovered from bentonite loss, costs the entire industry a fortune each year. Thus, we are investigating membrane filtration as an alternative to bentonite fining, which would have less impact on the aroma and flavour of the wine and reduce the production costs. This project is a mix of chemistry and engineering, which I find really interesting and also really relevant to the industry, which I find exciting.

 

What can you see yourself doing in the future?

For now, I am very happy about where I am, and I would like to focus on my project and devote myself to it. For my future career, I want to gain more experience through a couple of vintages and be exposed to more industry and winemaking processes. This will enable me to develop a practical mind for winemaking as well as increase my understanding of the needs of industry in terms of production of wine. After that, I will decide whether I want to continue my career in either research or industry. At the moment though, I’m really excited to be doing research that’s relevant to the industry. I feel that this project is potentially making a difference for the industry and helping the winemakers of South Australia.

 

Written by Robyn Stevenson, ARC TC-IWP intern