Just one brand of frozen vegetables on supermarket shelves use 100 per cent New Zealand-grown vegetables.
The rest - including Wattie's and McCain - supplement local produce with vegetables from China, Vietnam, South America, and the United States. Not that you would know from looking at the packet - all products meet New Zealand's food safety regulations but none need country-of-origin labelling. This is despite studies indicating more than 75 per cent of people prefer New Zealand-made food.
It's not hard to monitor where food comes from. Dunedin company Oritain has developed ways to pinpoint exactly where a fruit or vegetable is grown by analysing the microscopic "fingerprint" left by soil and rain.
Director Helen Darling said it was the "forensic science" of food - and testing was inexpensive and straightforward: "Consumers want to know where their food comes from. There's a need for transparency."
The Herald on Sunday asked Wattie's and McCain for information about their frozen vegetables. Both use the label: "Packed in NZ from local and imported ingredients." We wanted to know which vegetables came from overseas and the percentage grown in New Zealand.