The answer could be a lot less than you think. According to this article the Government will opt out of new EU rules which will set regulations as to how much meat mince must contain. The regulations will set a limit of 35% filler for minced beef and 48% for pork. Many products on sale in the UK, however, do not meet these limits meaning they would no longer be able to be labelled as mince under the new rules. For this reason ministers have asked for an exemption to the new regulations. It doesn’t surprise me that there are products on sale that contain this little meat but I am surprised people buy them. Personally I prefer to buy 100% minced meat from a reputable source and avoid the pale and rather nasty looking alternative product often sold in the supermarket.