Table 1.

Composition of ISF (inflating stomach formulation) and control solution (Control) and results of inflating rate of these solutions in vitro.

Component	unit	【ISF】	【Control】
1) Low methoxyl pectin	mg	1,850	0
2) Citric acid monohydrate	mg	200	200
3) Sodium benzoate	mg	92.5	92.5
4) Sodium hydroxide	mg	400	400
5) Non-carbonated water	ml	0	185
6) Carbonated water	ml	185	0
pH		3.8 ± 0.2	3.7 ± 0.02
Gas volume	GV	2.89	0
Inflating rate (after 10 min)	%	244.1 ± 3.2	100.0 ± 0.0

The preparation methods of ISF and control solution were described in Materials and Methods. Inflating rate was calculated from the results of in vitro inflating experiment (see Materials and Methods). In brief, ISF or control solution at 5°C was added to artificial gastric juice gently and was left to stand at 37°C for 10 min. The volume of solution and bubble-containing gel were measured using the scale of a quantitative measuring flask and then calculated as inflating rate.