Questionnaires in the form of postcards are being handed to passengers asking what level of food import controls they experienced when they arrived back in the UK.
President of the National Farmers’ Union Ben Gill said: "Illegally imported meat and food can be the vehicle for the introduction of exotic livestock disease into the country. It's vital proper controls are in place.
The NFU aims to distribute about 10,000 postcard questionnaires to assess the effectiveness of the Government's campaign against illegal imports and is urging travellers to fill them in and post them back to the NFU.
NFU Food Standards Chairman, Michael Seals said: "Foot and mouth demonstrated just how exposed Britain is to potentially devastating disease and pests that attack our livestock, crops and plants.
“It is paramount that the importation of meat and food from outside the UK is subject to strict controls and the NFU wants to gauge just how comprehensive DEFRA's efforts have been."