Making the decision to go organic or biodynamic is a major one for grapegrowers.
The certification conversion period alone can take up to three years, and there’s no guarantee that the wine will taste better.
Or is there?
A new review published in the prestigious American Journal of Enology and Viticulture (February 2019) has found when it comes to taste, ‘going organic’ consistently produced positive results.
One of the studies highlighted in the journal review article, led by Associate Professor Cassandra Collins from the University of Adelaide’s School of Agriculture, Food and Wine, assessed organic and biodynamic viticultural practices in Australian conditions to understand their impact on productivity and quality.
The paper reviews research studies conducted worldwide, comparing effects of conventional, organic, and biodynamic viticulture on soil properties, biodiversity, vine growth and yield, disease incidence, grape composition, sensory characteristics, and wine quality.
Key findings of the review included:
- soil nutrient cycling was enhanced under organic viticulture – especially after conversion was completed
- 17 out of 24 studies observed a clear increase in biodiversity at several different levels (e.g. in plants, in insects) under organic viticulture
- organic and biodynamic treatments showed 21 per cent lower growth and 18 per cent lower yield compared to conventional viticulture, and
- no consistent differences in basic berry, juice or wine composition among management systems were observed.
However, it was the findings on taste that took Associate Professor Collins and co-authors by surprise.
‘We were surprised that wines made from organically and biodynamically grown fruit were consistently described by assessors as being more complex, vibrant and textural with greater fruit character compared to wine made from fruit managed using high input conventional management practices.’
An interesting result when you consider that all the tastings were replicated blind tastings with experts from the wine sector.
Associate Professor Collins said demand for organically grown crops had increased in the past few decades.
‘Particularly in the wine sector, the use of organic and biodynamic management systems is more common, with some of the most prestigious wineries converting to organic or biodynamic viticulture.’
‘This research is important, because it gives us insight into how long it takes for these types of management systems to have an impact. To become certified for both organic and biodynamic viticulture requires a conversion period of around three years – so it is helpful to look at the validity of the conversion period.’
Associate Professor Collins said she believed the movement towards organic and biodynamic has had a positive effect across the sector.
‘Vineyard management has changed significantly over the past few decades in terms of the number and type of inputs we apply. Organic and biodynamic management use a holistic approach and as such has made us more aware of the whole environment in the vineyard.
‘For example, more producers are focusing on soil health and the use of mulches and composts to improve nutrient and water availability to the plant has become more common practice.
‘There has also been a shift in thinking about the aesthetics of the vineyard floor and the impact of herbicides on the vineyard and the people using them, which has led to a significant reduction in the amount of herbicide applied to vineyards.’
She hopes that research on the optimisation of organic and biodynamic viticultural practices in the different environments continues to focus on vineyard floor management strategies, nutrient supply, disease incidence, yields and cost structure.
Work is currently in progress, with University of Adelaide researchers investigating the use of different plant species undervine.
The paper ‘Organic and Biodynamic Viticulture Affect Biodiversity and Vine and Wine Properties: A Systematic Quantitative Review’ from the American Journal of Enology and Viticulture can be accessed here.