The Big Picture has carried out studies for clients such as Unilever in categories such as tea and ice cream. "Sustainability is very low in the hierarchy of factors influencing purchases, and in some product areas it has virtually no impact at all," said director Suranee Abeysuriya.
She explained that consumers interviewed tended to filter out explicit claims and logos. "In tea and coffee, people were generally aware of the Fairtrade logo," she said, but added that they also picked out other products as being 'sustainable' on the basis of on-pack imagery.
Other logos, such as the Rainforest Alliance, were less well understood. Overall, she said, a proliferation of claims and logos undermined a brand's credibility.
"What food brands are doing more now is building an emotional connection, whereas a few years ago, it used to be more about functional benefits," said Abeysuriya.
The research did identify a significant awareness of packaging reduction. "Where they had a choice, many consumers would prefer a simpler pack with fewer layers or components," said Abeysuriya. "In the end, whether consumers want to trade freshness for sustainability is another matter."
Whatever their credentials, products packed in paper and board or glass tended to be seen as more sustainable. But functionality appeared to override this. "When asked to compare the sustainability of a board and a plastic pack for ice cream, most of the conversation hinged on whether the product would melt or not," she said.
Compared with, say, Germany, there was a lack of education among UK consumers about different packaging materials, she said. "There's a lot of confusion about whether food cartons, for instance, are recyclable."
The British Retail Consortium (BRC) agreed. "There was an element of consumer scepticism, but more of the larger companies and local authorities are improving their communication about what they're doing in recycling," said food policy director Andrew Opie.
The BRC administers the On-Pack Recycling Label (OPRL), used to inform consumers about packaging recycling. "The beauty of the OPRL is its consistency across such a wide range of product types, both branded and own-label," said Opie.
The Waste & Resources Action Programme (WRAP) helped to set up the scheme in 2009.