Some stats:
James Porterfield cited the Bureau of Railway Economics 1924 (p. 102) in his book, Dining by Rail. Up to 4,000 cows working day and night produced 6 million quarts of milk and cream. (That was for dining cars alone.) He translated the amount into cubic feet and said it would float the ship, Leviathan. The 6 million quarts that the Bureau recorded didn't include the ingredients for the 900,00 quarts of ice cream served on the cars.
TRRR