Science Past from the issue of June 20, 1959

Mechanical cow eats grass — A mechanical “cow” has just started work at the British Agricultural Research Council’s experimental station at Rothamsted, near London. Its function is to extract protein from leaves or grass or any suitable vegetation…. Grass or other vegetation is fed into the machine from a normal elevator. After being chopped, the grass enters a press and the juice is squeezed out of it. This juice, which contains the bulk of the protein and barely any cellulose, is then treated with steam to precipitate the protein. When the protein is made solid by the precipitation, it requires only a filtering to separate the protein from the unwanted juice. With a few minutes the “cow” has produced solid, cake-like protein from vegetation and, what is more important, has collected at least 50% of the protein in the leaves.… The protein cake then goes to 
[Scotland] where it is used in experimental feeding of pigs.