What kind of food is bolus?

"Bolus" is not a specific type of food. It's a term used in physiology to describe a rounded mass of food that has been chewed and mixed with saliva, ready to be swallowed.

So, bolus can refer to any food that is in this stage of digestion, whether it be bread, meat, vegetables, or anything else you might eat.

Perhaps you were thinking of a specific food item that is called "bolus"? If so, please provide more information!