Uncorking the flavour with research – Using native yeasts to produce white wine

Nova Scotia has become a favourite stop for wine lovers and it’s easy to see why; the beautiful scenery, large variety of wine selections and the community of world-class winemakers. In fact, the province’s wine industry attracts more than 150,000 visitors annually. While traditional wines remain a timeless choice for wine lovers, the Nova Scotia industry is seeing strong interest in lower alcohol and non-alcoholic wines.

Dr. Lihua Fan in her lab at the Kentville RDC.

A research team led by Dr. Lihua Fan, located at the Kentville Research and Development Centre (RDC) at Agriculture and Agri-Food Canada (AAFC), has discovered that naturally occurring yeasts in Nova Scotia can produce white wines with distinctive flavor profiles and reduce the alcohol content by 2 to 3%. Traditionally, winemakers rely on commercially available yeasts which typically produce an alcohol content of 11-13%. Her discovery may just be the answer that producers are looking for!

Dr. Fan began researching native yeasts in 2018, focusing on improving wine quality through fermentation technology. Dr. Fan along with Dr. Gavin Kernaghan (Mount Saint Vincent University), Dr. Marcia English (St. Francis Xavier University), industry representatives and AAFC researchers in Nova Scotia, British Columbia, Ontario, and Quebec collaborated on various research projects to foster sustainable growth of the Canadian grape and wine sector.

“In recent years, the wine industry has been booming in Nova Scotia. We see a lot of wine and grape development in the province. There was a need from industry to investigate native yeasts in the Atlantic provinces, as there was limited research done. Why is this so important? We know that native yeasts are active at early fermentation stage and influence alcohol content, pH, viscosity, colour, and flavor compounds contributing to the flavor and aroma of the resulting wines. I was interested in researching how our native yeasts impact wine quality.”

- Dr. Lihua Fan, research scientist, Agriculture and Agri-Food Canada

Under the microscope: the microbial world of yeast

“Yeast” is a generic term that is used to describe a number of species of single-celled microorganisms. In winemaking, the primary role of yeast is to convert the sugars present in the grape juice (such as glucose and fructose) into alcohol. Yeast is also partly responsible for the flavour characteristics in wine, and different species have differentiated effects on the final flavour of a wine. This is one of the reasons why wines made in different regions have distinctive tastes.

Yeast naturally occurs on the skin of grapes and the leaves of the plant. Dr. Fan and her team collected grape samples from multiple vineyards in Nova Scotia and brought them back to her lab in Kentville. Yeasts were isolated through fermentation of grape juice as well as by sampling directly from grape surfaces.

After identifying 300-400 yeast strains through DNA sequencing, Dr. Fan’s team conducted a series of chemical and enzyme tests to evaluate their fermentative potential and ability to contribute desirable flavours to the wine. The selected yeasts were tested in various wine fermentation trials, with a commercial yeast strain used as the control. To ensure that wine created with these native yeasts would appeal to consumers, Dr. Fan’s team analyzed key quality attributes such as alcohol content, sugars, organic acids, and other aroma- and flavour-related compounds.

The wine samples created in her lab were also sent to the sensory evaluation panelists at Acadia University. The results indicated that the wines produced using native yeast had good flavour with appealing fruit and floral attributes. Dr. Fan’s research found a way to lower the alcohol content while creating flavourful wines!

“When we got the results back from the sensory evaluation panelists at Acadia University, it was a very good surprise. The panelists enjoyed the wines created using the native yeasts! This unlocks the potential of native yeasts from local vineyards to create wines with flavor profiles that reflect their local wine-making regions."

- Dr. Lihua Fan, research scientist, Agriculture and Agri-Food Canada

Photo gallery

Nova Scotia grapes

Native yeasts isolated and purified

Dr. Fan’s fermentation trials

Related information

• Kentville Research and Development Centre
• Fan, L. et. al. Non-traditional yeasts from cool-climate vineyards for novel low-alcohol wines. Plants People Planet. 2024; 1–13. DOI: 10.1002/ppp3.10579