Science

If the sensor goes pink, then don't drink

If the sensor goes pink, then ...
New sensor technology may make it easier for brewers to gauge the freshness of beer
New sensor technology may make it easier for brewers to gauge the freshness of beer
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Users first expose one of the discs to a beer sample, and then take a photo of that disc on their smartphone
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Users first expose one of the discs to a beer sample, and then take a photo of that disc on their smartphone
New sensor technology may make it easier for brewers to gauge the freshness of beer
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New sensor technology may make it easier for brewers to gauge the freshness of beer

Unlike wine, beer doesn't age well. It goes stale, becoming a foul-tasting concoction that breweries certainly shouldn't be sending out to stores or bars. While brewers do already perform tests to gauge freshness, those typically involve expensive gas chromatography equipment and take time to conduct. Soon, however, a simple color-changing sensor and an Android app may be all that's required.

Developed at Spain's Complutense University of Madrid, the technology incorporates small polymer discs that contain a derivative of the organic compound aniline. That derivative reacts with another compound that's given off by beer in increasing amounts as it ages, known as furfural – the greater the amount of furfural that's present, the more the disc will change in color from yellow to pink.

Users first expose one of the discs to a beer sample, and then take a photo of that disc on their smartphone
Users first expose one of the discs to a beer sample, and then take a photo of that disc on their smartphone

Users first expose one of the discs to a beer sample, and then take a photo of that disc on their smartphone. The app will analyze its color, determining a freshness rating based upon it. If the polymer has turned too pink, the beer will be deemed stale and undrinkable.

In lab tests performed on beers of varying ages, the new technology closely matched the accuracy of tests performed using more complex gas chromatography and mass spectrometry equipment.

Source: Plataforma SINC

4 comments
BartyLobethal
The colour of the discs in the image will depend at least as much on the quality of the lighting used to acquire the image as it will on the level of furfural in the beer. This might work sitting in a beer garden on a sunny day, but the (artificial) lighting in most venues is an awful mixture of fluorescent, incandescent, neon and LED. Good luck getting consistent colour results from that.
TheSplund
I tend to find that I can tast and/or smell if a beer is stale - I could write that impression down on a piece of paper and photograph with my phone and have an app analyse my findings I suppose
Harvey
@BartyLobethal: perhaps the dots could be on a card printed with one or two printed reference colors? But even then, the accuracy would still be suspect making you wonder if the app falls on the side of a little less or a little more stale.
J4rH43d
Weak beer does not age well. If a beer is more than 8% or so, it can actually benefit from some aging. I have several 12% beers that have mellowed and gotten complex over a decade of aging, similar to fine wines. They require the same kind of storage conditions.