Optimal Food Matrix Model for Digestibility and Bioavailability of Calcium and Zinc

Table 2

Composition and concentrations of digestive juices.

Secretion	Saliva	Gastric juice	Duodenal juice	Small intestine juice
Reagents	3 M NaCl; 0.41 M urea; 0.09 mM uric acid	1.0 M HCl; 0.15 M CaCl2; 1 g BSA	0.83 M KCl; 0.15 M CaCl2; 1.0 g BSA	1.0 M NaHCO3; 0.15 M CaCl2; 1.8 g BSA; 30 g bile
Enzymes	90 mg α-amylase; 25 mg mucin	2.5 g pepsin; 3 g mucin	9 g pancreatin; 1.5 g lipase	—; —
pH	6.8 ± 0.2	1.50 ± 0.02	8.0 ± 0.2	7.0 ± 0.2

BSA = bovine serum albumin.