What's more bad than serving a stale beer on your party? But we all know that it's very difficult to predict its freshness. That's why a mobile application has come to the rescue.
Chemists from the Complutense University of Madrid have developed a method that allows brewers to measure the freshness of beer by using a polymer sensor that changes color upon detecting furfural - a compound that appears when this beverage ages and gives it a stale flavor.
‘A smartphone app indicates whether your beer is fresh or stale by a simple color change. The intensity of the color depends on the concentration of furfural, a compound that appears when this beverage ages and gives it a stale flavor.’
The sensor can be controlled from a smartphone app.
Depending on the beer type and its storage conditions, its flavor may be altered as a result of changes in the chemical composition produced during beer that, unlike what occurs in wines, has a negative effect on the quality of the flavor.
Now, the researchers Elena Benito-Pena and Maria Cruz Moreno-Bondi developed a simple, low-cost method capable of measuring whether or not beer has gone stale.
Until now, brewers have measured furfural and other freshness indicators using methods based on chromatography techniques.
"But these methods involve the use of expensive equipment and sample preparation is very time-consuming," said Benito-Pena.
The new method consists of sensor discs that detect the presence of furfural in beer.
These sensors, made from a polymer similar to the one used to manufacture contact lenses, have been designed to change color (from yellow to pink) when they come into contact with a beer containing furfural.
"We have incorporated a derivative into the sensor material which reacts with the furfural and produces a pink cyanine derivative that allows us to identify the presence of the marker in the sample," the chemists explained.
"The intensity of the color increases as the concentration of furfural in the beer rises and, thus, as more time passes since the beer was produced," they added in a paper published in the journal Analytical Chemistry
The team has also created a mobile app for Android smartphones that, by taking a picture of the sensor disc, allows for the identification of the amount of furfural present in the beer.
With this data, the degree of freshness can be determined. The app is available as open source and any programmer can utilize and modify it to be used on other platforms. It will also be available for Apple IOS devices soon.