旧时用蓬灰主要成份应是碳酸钾,说是有助于软化面劲,提高延伸性.

食品加工文献说:
"As the surface-active function of the alkaline water under presence of hydroxyl-ion is higher than that of city water or well water, impregnation of the water into wheat flour is smoothly effected to promote partial swell of starch particles so that the starch is pasted by alkalinity to increase an amount of hydrator. This is effective to enhance the water retention property of dough." (ZT)