. . . "Effervescence generators that are effective under acid or neutral pH conditions include a combination of at least one alkali metal carbonate or bicarbonate, such as sodium bicarbonate, sodium carbonate, sodium sesquicarbonate, potassium carbonate, potassium bicarbonate, germanium sesquaoxide or mixtures thereof, in admixture with at least one non-toxic, physiologically-acceptable organic acid, suc" . . . . . .