Additional Soaking
I left the beans, one with a new dose of baking soda, the other covered with water. Again, each batch was soaked in 3 cups of water, and again left overnight, so the new soaking time was 27 hours, and in total the soaking time was 41 hours.
After the second soaking, there was little change in the weight of the beans, 393g with baking soda (up from 388g before) and 396 without soda (no change from the day before).
Both pots had a foam or froth on top of the water, but not much. This is similar to the foam that is created when one boils the beans after soaking, and is probably a sign that something is leached out and maybe ferments. Soaking is known to partially remove the gas inducing components in the beans, so maybe this is it.
The beans with the baking soda had a funky, musty smell. Fortunately, it disappeared in boiling, later on.
Boiling
Each batch of hummus (garbanzo beans or chick peas) was covered in 3 cups of tap water, brought to a rolling boil with highest setting of the range (it took about 7 minutes to reach boiling), then simmered for 90 minutes, then left to air cool, separated from the cooking liquid, weighed and tested.
After cooking, the beans soaked with baking soda were substantially heavier than the ones who were soaked in water (482 grams vs. 452 grams final weight). The volume was about the same with both batches, but the beans soaked with baking soda were softer and mealier. The baking soda soaked beans felt ready to disintegrate, while the water soaked beans felt more structurally integral. The peels remained in both cases, so all the beans actually remained intact.
Conclusions
1. Soaking beans with a little baking soda makes them softer when cooked, but does not affect them much during the soaking process.
2. Overnight soaking is probably sufficient – I do not have a comparison of cooking after one night and two night soaking, but I did not like the way the beans smelled when left for so long.
3. Something has to be done about the peel, especially if attempting to make M’shawsha – hand mashed hummus.