How do we know the food we are buying is fresh, was properly frozen or kept at the correct storage temperature during shipment or that it is free of dangerous bacteria?
Usually, we do not. We take a great deal on faith, trusting that the goods were handled properly during each of the many steps from manufacture through distribution and finally to display.
If something has gone wrong, we usually pay for it by suffering a stomach bug.
A cross-Border research initiative hopes to improve the odds, however, by developing food packaging that can inform us if something is not right.
Dr Dermot Diamond, a research director at DCU's Biomedical Environmental Sensor Technology (BEST) laboratory, described packaging products being developed to keep foods safer.
One project looks at packaging that changes colour if the food is off, another involves wrappers that scavenge for oxygen to keep red meat looking better when on display.
Another complex project involves fitting radio transmitters and sensing equipment to frozen food pallets to guarantee proper handling by intermediary distributors.
There can be up to 30 steps in the distribution chain separating the manufacturer from the consumer, Dr Diamond said. If one shipper in this chain allows frozen food to thaw and then re-freezes it and a consumer gets ill, there are no responsibilities for the distributor. The manufacturer would pick up the pieces, he said.
The BEST lab is a cross-Border effort involving DCU, University of Limerick, University of Ulster at Jordanstown and Queen's University, Belfast. It is funded by the International Fund for Ireland and involves 40 full-time researchers at DCU alone.
Dr Diamond sees great opportunities in smart packaging. "The potential from a marketing point of view is very powerful. The European Union will definitely legislate in this area," he said.
Clearly the message is understood by industry as the research effort involves a "strong partnership" with a range of companies including Cadbury, Kerry Co-op, Monaghan Mushrooms, Smurfit and Analog Devices. "The nice thing is there is industry involvement at a very high level."
The system being developed for bulk handling of frozen foods provides "packaging that can sense its environment", Dr Diamond said. It automatically records temperature, sampling every 30 minutes over a two-week shipment period. Data can be downloaded at any stage during intermediate handling and can be coded to prevent tampering. The system can be adjusted simply to show green for proper handling or red for danger or it could give an entire listing of measurements, broadcast by a tiny radio transmitter and picked up by quality control staff.
Developing wrappers that react to the food they contain, changing colour if high levels of bacterial activity are present, is another project under way at DCU. Initial work is on packaging for fish which detects trimethlyamine, the substance that causes a fishy odour.
Wrappers that detect oxygen are being developed, useful for sterilised medical products. Surgical pre-packed kits often exclude air and the presence of oxygen would warn the pack had been punctured or opened to outside contamination.
The meat packs respond differently, mopping up oxygen which causes prepacked meat to go too red when on display. It would be used along with vacuum packing to keep meat safer and looking right.
These developments were important because they added to consumer confidence, Dr Diamond said. Smart packaging provided a marketing advantage to the company that could show the consumer the food was safe and was handled properly.