AI-powered ‘electronic nose’ sniffs out meat freshness

A team of scientists at NTU Singapore has invented an artificial olfactory system that mimics the mammalian nose to assess the freshness of meat accurately.

This ‘electronic nose’ (e-nose), described in a paper published in the scientific journal Advanced Materials in October, could help to reduce food wastage by confirming to consumers whether meat is fit for consumption, more accurately than a ‘Best Before’ label could, said the research team from NTU Singapore, who collaborated with scientists from Jiangnan University, China, and Monash University, Australia.

The e-nose comprises a ‘barcode’ that changes colour over time in reaction to the gases produced by meat as it decays, and a barcode ‘reader’ in the form of a smartphone app powered by artificial intelligence (AI). The e-nose has been trained to recognise and predict meat freshness from a large library of barcode colours.

When tested on commercially packaged chicken, fish and beef meat samples that were left to age, the team found that their deep convolutional neural network AI algorithm that powers the e-nose predicted the freshness of the meats with a 98.5 per cent accuracy.

Co-lead author Professor Chen Xiaodong, the Director of Innovative Centre for Flexible Devices at NTU, said: “These barcodes help consumers to save money by ensuring that they do not discard products that are still fit for consumption, which also helps the environment. The biodegradable and non-toxic nature of the barcodes also means they could be safely applied in all parts of the food supply chain to ensure food freshness.”

A patent has been filed for this method of real-time monitoring of food freshness, and the team is now working with a Singapore agribusiness company to extend this concept to other types of perishables.