Slow Cooking Beans

Reading through David Tanis' "A Platter of Figs", one statement grabbed my attention and made me scratch my head a bit: "A bean soup needs gentle cooking and cannot be rushed." No explanation, just a terse pronouncement that assumes you'll take it on faith that the great Tanis would not lead you astray on this or any other point. Tanis' unadorned prose is certainly one of the great things about "A Platter of Figs," and it matches well the book's simple food that pays homage to fine ingredients rather than complex technique. Usually the text offers just enough information, but once in a while, as with the bean soup, it falls short.

"Do beans really need slow cooking?" I asked myself upon reading Tanis' unequivocal statement. I tried to recall what I knew about beans. Not much. What about slow simmering? You have to simmer meat at relatively low temperatures to keep it moist and tender, but that's because meat cells lose liquid at high temperatures. Meat stocks are also simmered slowly, to avoid emulsifying fat into the liquid end product. But surely bean cells are different than meat cells, and for bean soup the fat is probably a non-issue for various reasons. I've never ended up with tough and dry beans; I've always boiled them and gotten satisfactory results.

I probably should have turned to Harold McGee for resolution, but instead I googled and turned up this article by Chef Kelly Myers.

Salient points:

• Slow cooking "breaks down gas-causing carbohydrates into digestible sugars."
  
• "Boiling will eventually blow apart your black-eyed peas, flageolets, and cranberry beans."
• Boiling might lead to unevenly cooked beans.
• Simmering leads to "creamy and luxurious beans," though why is seemingly left to the reader to wonder at.
  

I pulled a few more interesting ideas from Myers' article:

• use the 'stock' left over from simmering beans to add body to vegetable soups.
• add fat (for flavor) to the beans after skimming the foam (which is a protein that comes in with the beans). This might mean sweating/sauteing your aromatics/herbs/spices/meat/whatnot in another pan, then dumping it all into the beans post-skim.

And finally, one fascinating point from McGee himself:

• Acid, sugar, and calcium allow beans to cook for hours and reheat without disintegrating. So ingredients like molasses ( somewhat acidic, contains sugar and calcium) and tomatoes (acidic) preserve structure in slow cooking. Viz. baked beans.