This project underpins and enables the AWRI’s research, development and extension activities, through the provision of a range of cost-effective essential supporting services and efficient access to critical infrastructure. Specialist capabilities such as those of synthetic organic chemistry, expert instrumental equipment expertise or sensory science, including an available pool of screened, trained and qualified sensory assessors, are critically important for advances in wine science.
Twenty-six major sensory studies were completed in 2019/2020, mainly using quantitative sensory descriptive analysis, but with some studies involving more rapid methods such as projective mapping or Pivot© Profile. These studies generally used the AWRI’s highly trained and experienced dedicated sensory panel, but some also involved winemaker panels.
Twenty-five triangle tests were completed for a range of projects, along with 32 technical quality panel sessions, predominantly for helpdesk investigations. Eleven sensory sessions were undertaken to assess smoke characters in wines made from grapes exposed to bushfire smoke, using a specialised panel rating ‘smoke’ aroma and flavour, in comparison to unaffected control wines. A study assessing the responses of a group of highly experienced winemakers to smoke-affected wines was completed, comparing their responses to that of the AWRI smoke panel. The results showed that both panels performed similarly and well, with the winemakers more prone to ‘false positive’ responses, giving some smoke ratings to unaffected wines. This highlighted the need to include controls in industry smoke assessments. A consumer preference test was completed to assess the degree of acceptability of wines with varied degrees of smoke flavour.
Synthetic organic chemistry
Several new deuterated analytical standards and replacement compounds were sourced. A number of synthetic options were reviewed for preparation of deuterated compounds.
New procedures for sourcing grapes for research trials were developed and implemented for the 2020 vintage. This included an online form used by research staff to capture grape-related specifications and subsequent winemaking requirements, which was integrated with WIC Winemaking Services’ systems. In addition, a grape supply agreement template was developed with input from industry suppliers and was implemented for the purchase of six grape parcels for 2020 vintage trials.
One powdered and one liquid aspergillopepsin enzyme preparation sourced from overseas suppliers were found to comply with the Australia New Zealand Food Standards Code in terms of purity and source (Aspergillus niger). In addition, no allergens were detected in either preparation when tested by two analytical methods. Sub-samples of the enzymes and a third powdered aspergillopepsin preparation already held by the AWRI were provided to a PhD candidate at the University of Adelaide ARC Industrial Transformation Training Centre for Innovative Wine Production, as part of ongoing support for a project examining the potential use of ultrafiltration in the protein stabilisation of wine. Sub-samples of the two powdered aspergillopepsin enzyme preparations were also provided under a Materials Transfer Agreement to a student at Flinders University, for use in a project related to the protein stabilisation of wine.
Support was provided to an AWRI project examining the application of Della Toffola Maceration Accelerator technology (DTMA) to Shiraz winemaking. Four McLaren Vale vineyard blocks were selected following extensive consultation with the collaborating industry partner, and five panels of twelve vines in each block were tagged and sampled weekly between veraison and harvest. Based on phenolics data from the analysis of the weekly samples, two blocks were chosen for commercial-scale DTMA treatment, and two days were spent in the industry partner’s winery performing the treatment. Multiple sub-samples of DTMA-treated and non-treated musts were then transported to the Hickinbotham Roseworthy Wine Science Laboratory for winemaking.
Leigh Francis, Angus Forgan