{"id":64111,"date":"2019-06-19T07:29:00","date_gmt":"2019-06-19T05:29:00","guid":{"rendered":"https:\/\/renewable-carbon.eu\/news\/?p=64111"},"modified":"2019-06-14T12:52:38","modified_gmt":"2019-06-14T10:52:38","slug":"food-freshness-sensors-could-replace-use-by-dates-to-cut-food-waste","status":"publish","type":"post","link":"https:\/\/renewable-carbon.eu\/news\/food-freshness-sensors-could-replace-use-by-dates-to-cut-food-waste\/","title":{"rendered":"Food freshness sensors could replace \u2018use-by\u2019 dates to cut food waste"},"content":{"rendered":"
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PEGS, incorporated into packaging, could soon detect spoilage gases in meat and fish<\/figcaption><\/figure>\n

Imperial academics have developed low-cost, smartphone-linked, eco-friendly spoilage sensors for meat and fish packaging.<\/strong><\/p>\n

The researchers say the new sensors could help detect spoilage and reduce food waste for supermarkets and consumers.<\/p>\n

One in three UK consumers throw away food solely because it reaches the use-by date, but sixty per cent (4.2million tonnes) of the \u00a312.5 billion-worth of food we throw away each year is safe to eat.<\/p>\n

These new laboratory prototype sensors, developed at Imperial College London, cost two US cents each to make. Known as \u2018paper-based electrical gas sensors\u2019 (PEGS), they detect spoilage gases like ammonia and trimethylamine in meat and fish products.<\/p>\n

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PEGS are made of carbon electrodes printed onto readily available cellulose paper. (\u00a9 Imperial College London)<\/figcaption><\/figure>\n

The sensor data can be read by smartphones, so that people can hold their phone up to the packaging to see whether the food is safe to eat.<\/p>\n

Dr Firat G\u00fcder’s<\/a> team at Imperial\u2019s Department of Bioengineering<\/a>, made the sensors by printing carbon electrodes onto readily available cellulose paper.<\/p>\n

The materials are biodegradable and nontoxic, so they don\u2019t harm the environment and are safe to use in food packaging. The sensors are combined with \u2018near field communication (NFC)\u2019 tags \u2013 a series of microchips that can be read by nearby mobile devices.<\/p>\n

During laboratory testing on packaged fish and chicken, PEGS picked up trace amounts of spoilage gases quickly and more accurately than existing sensors, at a fraction of their price.<\/p>\n

The researchers say the sensors could also eventually replace the \u2018use-by\u2019 date \u2013 a less reliable indicator of freshness and edibility. Lower costs for retailers may also eventually lower the cost of food for consumers.<\/p>\n

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\u00a9 Imperial College London<\/figcaption><\/figure>\n

Dr\u00a0G\u00fcder\u00a0said: \u201cAlthough they\u2019re designed to keep us safe, use-by dates can lead to edible food being thrown away.\u00a0In fact, use-by dates are not completely reliable in terms of safety as people often get sick from foodborne diseases due to poor storage, even when an item is within its use-by.<\/p>\n

\u201cCitizens want to be confident that their food is safe to eat, and to avoid throwing food away unnecessarily because they aren\u2019t able to judge its safety. These sensors are cheap enough that we hope supermarkets could use them within three years.<\/p>\n

\u201cOur vision is to use PEGS in food packaging to reduce unnecessary food waste and the resulting plastic pollution.\u201d<\/p>\n

The research is published in ACS Sensors<\/a>.<\/p>\n

Food waste<\/h3>\n

Consumers rely on use-by dates or even \u2018sniff tests\u2019 to see if their food is safe to eat, but there is currently no commercially viable, reliable alternative that provides objective feedback on food freshness and safety.<\/p>\n

Although developed by food technologists over many years to ensure safety, use-by dates don\u2019t take storage and processing conditions of specific food items into account. Thus, they can lead to safe and edible food being thrown away by shops and consumers. In addition, most of the food wasted is packaged in plastic, thus contributing to plastic pollution.<\/p>\n

First author of the study Giandrin Barandun<\/a>, also from Imperial\u2019s Department of Bioengineering, said: \u201cUse-by dates estimate when a perishable product might no longer be edible \u2013 but they don\u2019t always reflect its actual freshness.<\/p>\n

\u201cAlthough the food industry \u2013 and consumers \u2013 are understandably cautious about shelf life, it\u2019s time to embrace technology that could more accurately detect food edibility and reduce food waste and plastic pollution.\u201d<\/p>\n

Because PEGS work on high-value items like meat and fish, they could save money for shops and their customers, by reducing waste and by enabling shops to use targeted price reduction for specific items based on PEGS rather than use-by dates.<\/p>\n

Current sensors<\/h3>\n
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Consumers rely on use-by dates or ‘sniff tests’ (Source: Shutterstock)<\/figcaption><\/figure>\n

Existing food spoilage sensors are either too expensive for common use (often comprising a quarter of overall packaging costs) or too difficult to interpret. Some types, like colour-changing sensors, could in fact increase food waste as consumers might interpret even the slightest colour change as \u2018bad food\u2019.<\/p>\n

PEGS aim to address both these issues. As well as being cheaper to produce and easier to interpret with electrical readings, the authors found that PEGS overcome many of the disadvantages of current gas sensors:<\/p>\n