Sensor roots out rotten spuds

Scientists at the University of the West of England have developed a sensor that can ‘sniff out’ rotten potatoes and save the food industry over £5 million a year.

The sensor works by detecting organic compounds in the air around potatoes and indicating which vegetables are infected. Bacterial soft rot – caused by the bacterium Erwinia carotovora – spreads quickly in vegetables held in storage and costs the food industry approximately £5.7 million a year.

The infection also causes an increase in the concentration of organic compounds above the tubers and scientists have developed a heated ceramic sensor which ‘sniffs out’ the gases to spot the rot.

In normal air, the sensors have an electrical resistance that depends on the concentration of oxygen present.

If the infection is present, the oxygen reacts with the organic compounds and prompts a change in the sensor’s resistance.

The prototype sensors are relatively cheap and can identify one rotten spud among 900 normal potatoes.

‘This important research could have a major impact on the food industry in producing higher quality potatoes combined with cost savings,’ said Researcher Dr Norman Ratcliffe.