|POTTER, R - Washington State University
|EDWARDS, C - Washington State University
|ROSS, C - Washington State University
Submitted to: Northwest Center for Small Fruit Research Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/20/2021
Publication Date: 12/22/2021
Citation: Potter, R., Edwards, C., Lee, J., Ross, C. 2021. Oxidation in white wine as assessed by the electronic tongue: year 1. Northwest Center for Small Fruit Research Proceedings. Virtual, Corvallis OR, December 2021.
Technical Abstract: Early detection of wine faults is especially important in winemaking for timely mitigation of flaws and prevention of financial and physical losses of wine. Previous research has shown that the electronic tongue (etongue) was effective for the early detection of wine faults in red wines. Extending this technology to white wines, the objective of this study was to assess the capability of the etongue in detecting oxidation in white wine varietals. Bottles of white wine varietals, including Oaked Chardonnay, Pinot Gris, and Dry Riesling, were opened and stored at 19°C for 15 days. These wines were sampled daily and evaluated using the etongue and assessed spectrophotometrically for color changes. In addition, each day, wines were evaluated by sensory panelists using the difference from control method to assess the magnitude of difference between the stored sample and a control (fresh) sample. Results showed that over the 15-day storage time, the etongue was capable of discrimination. On Day 1 of storage of all white wine varietals, the etongue discriminated between the stored wine and the control wine with a discrimination index of >80. In comparison, sensory panelists detected a difference between the stored wine and control wine at Day 2 of storage for Dry Riesling, at Day 4 for Oaked Chardonnay and Day 5 for Pinot Gris. Compared to appropriate controls, significant color changes in the white wines were evident by Day 3 of storage for Pinot Gris, Day 4 for Dry Riesling, and Day 5 for Oaked Chardonnay. These results suggest that the etongue is an effective tool for the early detection of oxidation in several white wine varieties, identifying significant difference before detection by sensory panelists or spectrophotometric color changes. Future research will continue to explore the application of the etongue for the detection of other wine faults in white wines.