Revolutionising food wrapping
MENTION food packaging and some people’s hackles rise over unnecessary layers of plastic or other wrappings. However, scientists are working on several smart forms of sustainable packaging that can benefit consumers and help prevent food waste, according to Miranda Mirosa,
Erin Young and Phil Bremer, of the department of food science at University of Otago.
They were part of a group of New Zealanders attending a packaging conference in China late last year, and have come back enthused about some of the emerging technologies and the different needs of the China market.
Prof Phil Bremer explains packaging is complex and serves many functions, including aesthetic, information, safety, practical, and cultural — there is no simple one aspect fits all.
However, he says that expected sustainability and recycling regulations are causing a major rethink about food packaging.
Erin Young, a packaging technologist and PhD candidate funded by NZ Food Safety Science Research Centre, says sustainability used to be a lower priority for food packaging but now it’s as if the iceberg’s tipped over.
‘‘We have 60 years where packaging is done a certain way — plastic has become very much embedded into the system and so it’s a paradigm shift for the industry. If we stop using plastics what are the alternatives and how does our supply chain readjust to all those things?’’ she said.
Dr Mirosa points out consumers have a tendency to think packaging is bad in terms of sustainability but if you take a lifecycle perspective including shelf life and food waste, packaging can be a good return on investment and a small part of the total energy of the resources that have gone into growing the food.
‘‘If we know that huge amounts of cucumbers are wasted and it has a massive environmental toll and if you can package them and they will last longer, people will hopefully eat them. It’s not the best solution but it’s better than wasting them. The best solution is people changing what they do: store it better, buy more frequently, eat what they buy, buy what they need. That is all changing practice and that requires people to make an effort,’’ she said.
‘‘I guess ideally if we were all prepared to eat locally then perhaps packaging wouldn’t be a need, but when we want to buy foods from the other side of the world and send our foods to the other side of the world and have foods that are out of season and that give us all the information we want, then packaging does serve a real role,’’ she said.
Scientists are working on new forms of smart packaging that could be as simple as compostable stickers on avocados and other fruit that measure the volatiles coming off naturally and indicate when it’s ripe so people don’t squeeze them to check.
Strips that absorb or emit oxygen, carbon dioxide or ethylene in punnets of fruit, such as strawberries, can extend shelf life for a few days.
An absorber in the cap on a bottle of juice that removes oxygen from the headspace means less preservative is needed to retain its fresh flavour.
Antimicrobials can be built into plastic film that stops microbial growth on meat, fish or cheese.
Already temperature indicators can be found on some packages, such as wine bottles or Chill Me Tim Tams, that change colour when the product is at the recommended temperature for serving.
Intelligent packaging can include time and temperature indicators that monitor a product through the supply chain and offer reassurance about food safety.
Some consumers are wary of technology around food, especially packaging that interacts with the food, and that’s one of the biggest hurdles around some of these technologies, says Dr Mirosa, who is particularly interested in consumer perspectives.
While most of us are not concerned about the safety of the food we buy because our regulations are reliable, it’s different in China. There, consumers distrust the system and are scared of tampering and adulteration. Good, secure packaging can give reassurance and confidence.
Prof Bremer points out that here we are quite happy to buy unpackaged apples but not all markets are comfortable doing that.
‘‘If you have a pack and the pack’s sealed, you have some confidence that it’s come from the farm in New Zealand as opposed to a bin of loose apples that could come from anywhere and have been treated with unknown chemicals,’’ he said.
‘‘People [in China] are scanning the QR codes and shopping online and part of the reason is they get more time to look at the company and customer reviews,’’ he said.
However, Dr Mirosa explained that packaging, especially for gifts, was sometimes over the top. She had seen manuka honey for sale at airports with several layers of gift wrapping, as it was a culturally important aspect of gift giving in China.
Nevertheless, they were surprised how the tide towards sustainability was changing, especially among younger Chinese consumers.
‘‘The research we are doing is really important. We can’t take what we know here and think it will work there,’’ she said.
A lot of the new smart packaging is about extending the shelf life of products, and while that is important for New Zealand suppliers, Chinese consumers don’t perceive that as a benefit.
Mrs Young said in China you don’t sell food on a longer shelf life, you sell it on better quality or freshness or more natural.
‘‘Shelf life is tied up to freshness and freshness is allimportant. In fact there were people who expressed preference for shorter shelf life,’’ she said.
However, some of the proposed smart packaging has challenges regarding sustainability, such as how the chips that track temperature and time are removed before the packaging is recycled, or whether they can be built from biomaterials.
Promisingly, many firms, including Amcor, one of the world’s biggest flexible plastic suppliers, are pledging to have all their packaging recyclable or reusable by 2025, Mrs Young said.
‘‘That is huge, so that’s going to be really good for helping the industry sort out how they manage it,’’ she said.