Well, it's more that the timing might vary by the natural pH of your water, not that you have to change anything.

But if you do want to play with your beans, then perhaps -

basic = bicarbonate of soda/baking soda
acid = tomatoes, vinegar, wine, citrus

Salt is more the end product of an acid/basic reaction. It affects texture through ionic balance of water through membranes. Also, a pinch of salt does wonders for bringing out flavor in grains and legumes. The other fun thing about salt is that it can neutralize the ability to taste bitter flavors.