Sending this again b/c my comment won't go through but,
"The food stack sizes that I can see on the mod page are as follows.
Steak: 8
Bread: 12
Chicken: 10
Apple: 16
Mutton: 10
Rabbit Stew: 6
Sweet Berry's: 32
Honey Bottles: 10
Pumpkin Pie: 8
Basically, the more hunger filled from a food item, the lower the stack.
For example:
- Steak only stacks up to 8 because it gives 4 food points, whereas sweet berry stacks up to 32 because it only gives 1 food point.
- The highest a food would stack would be 64, which would be the foods that give only half a hunger point (tropical fish, pufferfish, potatoes, beetroots, and any other half-point foods I missed.)
From there, you can probably calculate how other foods would stack & if you want to double-check, you can install the mod I linked and test it yourself. I hope that clears things up!"