Meat pies are less than one-third meat, while only half a chicken nugget is chicken flesh, a Fairfax Media investigation has found.

Pies sold by the big supermarket chains barely exceed the minimum government standard of 25 per cent meat, according to results from an independent accredited laboratory in tests commissioned by Fairfax Media.

Woolworths Home Brand pies contained 27.6 per cent meat, Four'n Twenty had 30.4 per cent and Coles Smart Buys 32.7 per cent. The analysis confirmed the presence of meat above the 25 per cent meat listed as an ingredient on the packaging.

The government standard for meat pies is 25 per cent ''fat-free flesh''. Fat-free flesh is described by Food Standards Australia New Zealand guidelines as being the skeletal muscle of a slaughtered animal, and can include animal rind, fat and connective nerves, blood, blood vessels and, in the case of poultry, skin.