TL;DR: 2.1 calories/gallon for almonds, 5.3 c/g for tofu, 1,558 c/g for beef.
Almonds consume 3.2 gallons of water each for just shy of 7 calories. 2.18 calories per gallon.
Cows consume ~3,200 gallons of water from birth to slaughter, where they produce about 6 million calories. 1,875 calories per gallon.
An additional 50 bales of hay to feed it over its lifetime (really hay is half the diet but its late and I'm just doubling it). Approximately 1,300 gallons per acre, which produces 100 bales - 13 gallons per bale - 650 gallons to grow the food. That is still 1,558 calories per gallon of water.
I found a recipe online that used about a gallon of water (rinsing and as an ingredient) for 1 pound of tofu. 10,000 gallons to produce one bushel (or 60 pounds) of soybeans. 166 gallons per pound. A pound is 2.6 cups, recipe wants 1 cup. 63 gallons per cup. 64 gallons made into tofu. 344 calories per pound of tofu. 5.3 calories per gallon of water consumed.