A recent study conducted by Washington State University researchers demonstrated the superior capability of “electronic tongue” (e-tongue) technology when detecting spoilage microorganisms in wine, in comparison to human sensory evaluation.

Wine fault monitoring is an important aspect of wine production, to ensure that products reaching consumers are safe and high-quality. Spoilage organisms Wickerhamomyces, Acetobacter, Lactobacillus, and Pediococcus are significant hazards that can affect wine chemically and create distinct aromas and tastes. Traditionally, winemakers have relied on their own, trained senses to describe a wine’s taste attributes and identify wine faults.

The present study sought to compare human sensory analysis of wines with emerging e-tongue technology in their abilities to detect wine faults caused by spoilage microorganisms. To do this, the researchers procured Riesling wine bottles and inoculated them with different bacteria and yeast cultures. The wines were analyzed both by the potentiometric e-tongue and a trained sensory panel. The e-tongue technology used in the study features seven cross-selective sensors that are coated in a membrane and are designed to measure the potential difference between ions and molecules in a sample, in comparison to a reference electrode.

Overall, the e-tongue was more sensitive than human palettes in detecting taste changes caused by microbial spoilage in the Riesling wine. The e-tongue was able to detect taste changes on day seven of storage, while the panel could not discern significant differences between the spoiled wine and unspoiled control wine until day 35.

The researchers underline the potential of e-tongue technology to aid early detection of microbial faults in white wines, suggesting that, if winemakers suspect the development of a wine fault, they could send a sample to a laboratory that provides e-tongue analysis.