Summary of the technology
In the proposed research we describe a novel, efficient and low-cost approaches for detection of acetic acid in wines. The first technique is based on the interaction of acetic acid volatiles with a specific receptor from the bacterium Bacillus subtilis. The receptor, which is encoded within a bacterial biosensor, will activate a reporter gene in the presence of volatiles of acetic acid.
Project ID : 8-2018-4662
Description of the technology
- Measurements of volatile acidity in wines can be a challenging issue in many young and aging wines. The primary acid that contributes to volatile acidity in wines is acetic acid. Its presence, above a specific threshold, indicates spoilage of the product. It is therefore important for wine producers and collectors to monitor constantly this compound, particularly during barrel aging which is prone to oxidation.
- The common method used to monitor volatile acidity in wineries is titration using a Cash Still, a method requiring training as well as a liquid sample of the wine. Furthermore, the high number of barrels in the winery cellar limits the ability of the winemaker to monitor each and every one of the barrels, thus putting the wine at high risk of spoilage in the most oxidation-sensitive stage of the wine making process.
- Several attempts have been made to produce "electronic noses" that could sense acetic acid in the wine’s headspace, however these devices have a problem coping with the high concentration of ethanol found in wines (which masks their sensitivity to acetic acid) and thus—to our knowledge— have not been successful to date.
- The proposed research project aims to use a “biological-nose” instead of an “electronic nose.” This biosensing cell is a genetically modified microbial organism, which is insensitive to ethanol, and can efficiently sense and report the presence of acetic acid.
Microbial biosensors for the quantitative detection of acetic acid in wine’s headspace, thus avoiding the need to obtain a liquid sample or open the wine barrels/bottles altogether.
The prototype will comprise a thin needle that can be introduced into the headspace through the stopper of a wine barrel or a bottle cork, and facilitate inspection of the wine without affecting the liquid or damaging the stopper.
The proposed technology will lead to a novel, easy-to-use tool for rapid and real-time analysis of wine condition, without the need to obtain a liquid sample, facilitating the rapid evaluation of numerous barrels of wine.
Additionally, the device could be used to detect acetic acid in other food-related products.
The novel sensor enables fast performance of a large number of tests, including each and every barrel and many wine bottles in the cellar, without the need to open the barrels or the bottles. This will significantly improve winemaking practice and assure high quality.