Only 38 per cent of Woolworths' home-brand or generic products and 55 per cent of Coles' home-brand products are Australian-made or grown, compared with 92 per cent of market leaders, said the consumer group Choice.
It compared the country of origin on 360 generic packaged food products, including biscuits, cereal, tinned goods and frozen foods, with the market leader.
It found Kelloggs Rice Bubbles is made in Australia while Coles' and Woolworths' rice cereals are made in New Zealand. Golden Circle Pineapple is purely Australian, made and canned locally, while the cheaper home brands by Coles and Woolworths are made and sourced in Indonesia.
"While it's clear that Coles and Woolworths support Australian produced products in the fresh food and bakery sections … it's a different story when you walk along the aisles," the Choice spokeswoman Ingrid Just said.
Coles and Woolworths yesterday stood by their commitment to buy and source locally produced and grown packaged foods. Woolworths said Choice had surveyed less than 20 per cent of its own-label range and ignored ALDI, which stocked close to 100 per cent of its own label.
Coles said Choice's sample was ''quite limited, given our total house-brand offer is substantially more than that''.
Choice surveyed the home brands because it was ''seeing heavy marketing and advertising'' where the supermarkets tapped into consumer demand for locally owned and produced packaged foods, Ms Just said.
Choice also said country of origin labels were confusing.
Coles said it was ''fair to say, there is some confusion with the current labelling regime. And Coles isn't opposed to moves to make it clearer to customers.''