'Electronic nose' determines food freshness

February 11, 2016, National Research Tomsk State University
Timur Muksunov is a research engineer at Tomsk State University (Russia). Credit: ©Tomsk State University

A new device analyzes gas mixtures using semiconductor sensors. Odor is determined by a combination of existing gases in the atmosphere. Researchers have found that the conductivity of a semiconductor probe changes during sedimentation of the gas molecules from the atmosphere, which indicates their presence, says Timur Muksunov. During manufacture, the sensor can be customized to react differently to various atmospheric gases.

However, according to the scientist, it is impossible to make a sensor that reacts to only one gas—the system is needed to achieve sensitivity and selectivity. This allows, via certain processing techniques, accurately identifying the in the air, which experiments confirm.

One of the experiments attempted to determine the freshness of fruits and vegetables. Fruits and vegetables emit , ammonia and other gases. The closer the sell-by date of the products, the more of these gases were detected.

"We investigated the apples: A control was refrigerated and the rest were left at room temperature," says the scientist. "After 12 hours, the device was able to identify that the unchilled fruit emits gases more intensively than the control fruit. Now, the vegetable warehouse receives products by their organoleptic characteristics, and using the device will more accurately determine the of products, which will affect quality."

The device is fully developed and is being tested for effectiveness.

Explore further: New prototype for remote detection of hazardous gases

More information: T. R. Muksunov et al. Increase in the Sensitivity and Selectivity of Semiconductor Gas Sensors, Russian Physics Journal (2015). DOI: 10.1007/s11182-015-0376-1

Related Stories

Sensor detects cable fire before it starts burning

November 26, 2015

Fires are frequently caused by smoldering cables. Novel sensors now help detect such smoldering fires at an early stage by analyzing the plastic vapors released by overheated insulating cables. Scientists of KIT and Karlsruhe ...

A miniature gas sensor for mobile devices

August 13, 2015

VTT Technical Research Centre of Finland has developed a miniature gas sensor that can be connected to mobile devices. Gas measurements made with smartphones will make activities such as the detection of internal air problems ...

Gas sensors sound the smoldering fire alarm

September 2, 2015

Smoke detectors are everywhere, but still thousands of people die in fires annually. Fire gas detectors, which detect carbon monoxide and nitrogen oxide, identify fires at an early stage. Thanks to a new measurement principle ...

Ultrasensitive sensors made from boron-doped graphene

November 2, 2015

Ultrasensitive gas sensors based on the infusion of boron atoms into graphene—a tightly bound matrix of carbon atoms—may soon be possible, according to an international team of researchers from six countries.

Recommended for you

Spore formation model could advance medicine

February 21, 2018

Michigan State University scientists have produced experimental and modeling results that shed light on how a particular type of enzyme functions during spore formation, potentially advancing human health and disease research.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.