I read more: “legally, German Mett is not allowed to contain more than 35% fat.” Preparation includes semi-freezes the porc at 2ºC (35.6ºF) and sells freshly prepare the same day. This will be difficult to find in France, as pork are kept around 4ºC (39ºC) or above.
Regional difference of Mett:
I see also it has been mentioned by Presunto here: