UK: FSA highlights raw milk rules
Posted: March 31st, 2011 - 7:10pm
Source: Food Standards Agency
The Food Standards Agency is reminding local authorities and dairy businesses about the rules on the sale of raw drinking milk and unpasteurised dairy products. This follows the announcement by Defra that cattle testing positive for bovine tuberculosis, known as TB reactors, are to be tracked using their DNA to further strengthen controls to prevent the spread of TB.
This action is being taken as emerging evidence suggests that some farmers in the South West of England and the Midlands have been illegally swapping ear tags of TB reactors.
The process of pasteurisation destroys the bacteria that cause TB and other pathogens that may be harmful to human health. The risk from consuming pasteurised milk or dairy products that may contain milk from TB reactor cattle is therefore very low.
There is no evidence that milk from TB reactor cattle is being used to produce unpasteurised milk for drinking, or unpasteurised dairy products. The risk to human health from consuming milk or dairy products that are unpasteurised and might be contaminated with TB bacteria is low.
Tim Smith, Chief Executive of the Food Standards Agency, said: ‘The health risks to consumers from this suspected fraud are very low. The Agency has taken immediate action to remind local authorities of food safety rules that must be followed, and will meet with producers, manufacturers and retailers to make clear the steps they must take to ensure food safety.’
The Food Standards Agency has written to all local authorities in England, Scotland, Wales and Northern Ireland, asking them to remind dairy producers of their responsibilities under the relevant regulations. There has been similar correspondence with retailers, manufacturers and specialist cheese manufacturers. The FSA will meet with representatives of the retail, manufacturing, dairy and farming sectors to emphasise the importance of dairy producers being aware of the controls they should follow.
Rules on TB and milk
Under the TB control programme, cattle are tested regularly to find out if they are infected with Mycobacterium bovis. If a cow gives a positive reaction to the test it is called a ‘TB reactor’ and must be isolated from the rest of the herd and slaughtered. Its milk must not be used for human consumption.
The milk from other animals in the herd must be heat treated, usually by pasteurisation at a minimum temperature of 72°C for 15 seconds, to destroy M. bovis. This must continue until the herd is declared free of TB.
In England, Wales and Northern Ireland, unpasteurised cow milk for drinking can only be sourced from TB-free herds. It can also only be sold direct from farms or direct from the farmer via routes such as farmers markets and milk rounds or as part of a farm catering operation. Unpasteurised milk may contain bacteria, such as salmonella and E.coli O157 that can cause illness, and must be labelled to let consumers know that the milk has not been pasteurised and may contain organisms harmful to health. Products made with unpasteurised milk, such as some cheeses, are more widely available and must be labelled as being ‘made with raw milk’ or ‘made with unpasteurised milk’ at point of sale. Unpasteurised dairy products can be sold in Scotland, but it is illegal to sell unpasteurised milk for drinking in Scotland.
The science behind the story
The bacterium M. bovis, which causes TB in cattle, can also infect humans. Only a very small number of human TB cases due to M. bovis infection have been reported in the UK in recent years and there is no evidence that these have been caused by recent consumption of milk or dairy products. The vast majority of human TB is caused by another bacterium, Mycobacterium tuberculosis.
If the identity of a TB reactor was switched with that of another cow it could mean that milk from a TB reactor would continue to enter the food chain. If this occurred, it would most probably be pasteurised as the vast majority of milk produced in the UK is pasteurised. The risk from consuming pasteurised milk or dairy products from a herd with TB reactors is considered to be very low as pasteurisation kills M. bovis and other bacteria that are harmful to human health.
The risk to human health from consuming unpasteurised milk and dairy products is considered low. There is no evidence that unpasteurised milk from TB reactors is entering the food chain and it is unlikely that milk from a TB reactor would carry M. bovis. This is because shedding of M.bovis in the milk is most likely to occur if the cow has tuberculous mastitis, which is a rare condition. Even if contamination did occur, the milk would be significantly diluted by milk from healthy animals. These factors mean that it is very unlikely that milk or dairy products on sale to the consumer would carry the very high levels of M. bovis that are needed to cause human illness.
The Advisory Committee on the Microbiological Safety of Food (ACMSF) is an independent committee that provides expert advice to the FSA on the microbiological safety of food. The ACMSF has recently considered the risks to consumers of meat and milk from cattle with evidence of M. bovis infection, concluding the risks from meat were very low, and the risks from properly pasteurised milk and milk products were low. These considerations were used to help inform the FSA’s assessment of risks in this case. The ACMSF papers for these discussions can be found at the links below.