Wine faults in Riesling wine as assessed by the electronic tongue and a rate-all-that-apply sensory panel

Authors: POTTER, RACHEL - Washington State University; EDWARDS, CHARLES - Washington State University; Lee, Jungmin; ROSS, CAROLYN - Washington State University

Submitted to: Annual Meeting of the Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 2/15/2023
Publication Date: N/A
Citation: N/A

Interpretive Summary: N/A

Technical Abstract: Early detection of wine faults is important in winemaking to minimize financial and physical losses of wine. A significant source of wine faults in white wines includes spoilage microorganisms within the genera Acetobacter, Wickerhamomyces, Lactobacillus, and Pediococcus. The etongue, an instrument designed to mimic human taste, is seldom used for early detection of wine faults. Thus, the objective of this study was to track wine fault development in Riesling wine with the etongue as compared to sensory evaluation. Bottles of Riesling wine were spiked with 10^4 CFU/mL cultures of A. aceti, W. anomalus, L. brevis, or P. parvalus, all microorganisms associated with white wine faults. Wines were stored at ambient temperature (~22.3 C) for 6 weeks. Wine treatments were assessed weekly with the etongue and a RATA sensory panel. Sensory panelists were trained to detect aromatic spoilage terms associated with selected microorganisms and non-spoilage terms associated with Riesling wine. Sensory data were analyzed using ANOVA and Tukey’s HSD. Etongue data were analyzed using PCA. After 1 week of storage, the etongue detected differences in wines treated with P. parvalus, L. brevis, A. aceti and W. anomalus, producing discrimination indices of 96, 94, 98, and 86, respectively. Over the six-week storage, significant sensory differences identified by the RATA panel did not present until week 4 of storage. At week 4 of storage, wines treated with W. anomalus had significantly higher intensities of mousy (p = 0.003) and butter aromas (p = 0.002) compared to control wine. On week 6 of storage, wines treated with L. brevis displayed significantly higher intensities of mousy (p = 0.042) and vinegar/nail polish remover aromas (p = 0.004) compared to control wine. Wines treated with P. parvalus and A. aceti did not display significant differences in intensity of aroma spoilage terms over the 6-week storage period. The etongue has the potential to indicate wine quality prior to sensory detection – without sensory fatigue. These results showed the etongue to be an effective tool for early detection of microbial spoilage in Riesling wine by identifying differences prior to RATA panelists.