Development of resources for the objective measurement of grape parameters to address ACCC recommendations

Abstract

This project worked with industry and regulatory stakeholders to develop standardised methods for the assessment of grapes for wine production, based on recommendations from a review undertaken by the ACCC Agriculture Unit. Standardised methods, endorsed by industry and regulatory bodies were developed and published for: 

• the measurement of key parameters in grapes 
• sampling in the vineyard, in the winery and at the weighbridge 
• validating secondary methods against the reference methods.

A range of training materials and tools were developed to support use of the methods.

Summary

In 2018–19 the Australian Competition and Consumer Commission (ACCC) Agriculture Unit conducted a market study of the wine grape industry. The study examined competition, contracting practices, transparency and risk allocation in wine grape supply chains. In its report on this study (ACCC 2019), the ACCC made several recommendations, which required the development of uniform national standards for grape quality assessment, along with an in-depth look into current guidance on best practice measurement and sampling approaches in the vineyard and at the point of fruit receival at the winery. 

This project took a feedback loop approach, convening an Industry Reference Group of grapegrowers, winemakers, regulatory representatives and researchers to explore the current industry guidance on the fair trade of grapes between growers and wineries. This information was then fed back to the AWRI for review and alignment with literature, prior to further comment from industry. Two primary quality measurements were highlighted by the ACCC as requiring Industry Endorsed Standard Procedures (IESPs) – namely, grape sugar levels (total soluble solids) and grape colour. A series of additional requirements were flagged, focused on achieving a representative sample in the vineyard at the point of harvest, and upon fruit receival at the winery or weighbridge. Further elements were addressed including the determination of matter other than grapes (MOG) and pest and disease levels. Procedural and guideline documents were developed for each of these elements to provide industry with guidance on how to use the standard methods. 

This project achieved its goals in providing clarity regarding measurement of the key parameters for wine grapes that are associated with payment or rejection. A range of guideline documents and robust IESPs were developed, reviewed by industry and published on industry peak body websites. Experimental work was conducted and published on the impacts of different extraction techniques on key grape parameters and this is also now available to industry to provide guidance on best practice. Finally, a review into the latest literature on wine grape sampling and testing has been completed and will be published in the near future. 

The Australian grape and wine industry now has a baseline set of information to guide best practice in the assessment of grape quality for payment purposes. This will form the basis for ongoing continuous improvement and assessment of new and emerging technologies as they become available.