A cooking apple is an apple that is used primarily for cooking rather than eating raw.
Cooking apples are larger, and can be tarter than eating varieties.
Some varieties have a firm flesh that does not break down much when cooked.
Culinary varieties with a high acid content become a froth when cooked, which is desirable for some recipes.
The British grow a large range of apples specifically for cooking, but such varieties are used worldwide, although apples are eaten raw are also used for cooking purposes.
Many apples are dual-purpose. (source)
Can Guinea Pigs eat cooking apples?
No, they can’t eat them, unfortunately. Because they are more sour and tarter in their taste, they are not good for guinea pigs to eat and will hurt their stomachs if they eat them.
For more foods that guinea pigs can and can’t eat, check out our guinea pig food list.