Digestion is the transformation of food, along the tract, into components small and simple enough to enter the body: the nutrients. Teeth and the stomach’s churning break food up; digestive juices — saliva among them — dismantle it further, piece by piece, until what was bread is a liquid mix of nutrients.
Examples
Example 25.4 (The bread turns sweet)
Chew a piece of plain bread very long — a slow count of sixty — and a faint sweetness appears. Nothing was added: saliva is already dismantling the bread into simpler, sweeter pieces. You have tasted digestion beginning.