Procedure comprising the stages of:- Homogenisation and first heat treatment (1) in which a temperature of at least 70 ºC is attained for over 10 minutes; Cooling (2) in a tank that is set to a temperature of below 30 ºC.- The process continues with filling, turning, blowing and marking (3) of the expiry dates.- A second heat treatment (4) is then performed in an autoclave at a sterilisation temperature greater than or equal to 110 ºC for a time that will depend on the quantity to be canned, until reaching f0≥6.