Summary of the digestion process
Mouth
Digestive
juice produced
Saliva
Stomach
Gastric juice
Small
intestine
Pancreatic
juice
from the
pancreas
Enzymes in
the juice
Salivary
amylase
Pepsin
Renin
Trypsin
Chymotrypsin
Amylase
Lipase
Substance
acted on
Starch
Substances
produced
Maltose
Proteins (e.g
milk
protein)
Proteins
Peptides
Starch
Fats
Notes
Slightly alkaline or neutral. Saliva helps
lubricate food.
0.5% hydrochloric acid conditions for pepsin
and kills most bacteria. Absorption of
alcohol and some water soluble vitamins.
Peptides and
Amino acids
Maltose
Fatty acid
and
Glycerol
Bile emulsifies fats and aids its digestion.
Bile from liver
Intestinal Juice
Fats
Peptidase
Lipase
Peptides
Fats
Maltase
Sucrase
Maltose
Sucrose
Amino acids
Fatty acids
and
Glycerol
Intestinal juice is secreted by cells in the
duodenum and ileum.
Most absorption of sugars, amino acids, fatty
acids, vitamins and minerals occurs in the
ileum.
Glucose
Glucose and
Fructose
Glucose and
Galactose
Lactase
Colon
None
© Food – a fact of life 2009
Lactose
Dietary fibre
Free fatty
acids
Gases
Breakdown of dietary fibre by bacteria.
Production of B12 and vitamin K by
bacteria. Some absorption of water takes
place in the colon.