Beans and Tomatoes

I just received my Gigante beans from Greece. I want to try this recipe, but is adding the tomatoes with the beans "don't do it" mantra just a wives tale similar to the "don't salt your beans before cooking", "don't wash your mushrooms" and "never scrub your cast iron pan"?

Susan W
  • Posted by: Susan W
  • October 14, 2015


Susan W. October 16, 2015
Well, the verdict is in. I followed the recipe exactly and these beans are delicious. Very buttery inside. Great flavored broth that was a delicious soaked up with crusty bread.

I don't know if this was such a success because of the long cooking time in the slow cooker or because the tomatoes were 14 ounces to 4 cups of stock.
I'm going to make Merrill's Brothy Garlicky beans with the other 8 ounces of beans. I'll put the tomatoes in at the end as the recipe calls for and see if there's a difference.

Either way, I highly recommend these wonderful beans and recipe.
Smaug October 14, 2015
Rumor is acidity toughens beans, and I suppose it does to some extent- I avoid vinegar, but tomatoes aren't all that acidic, and the amounts are usually pretty small- I've cooked a ton of beans with tomatoes- maybe they were tougher than they would have been otherwise, but not enough to worry about, or even to notice.
Susan W. October 14, 2015
Another wives take debunked.
AntoniaJames October 14, 2015
I have cooked beans -- Rancho Gordo, so age and quality were not at issue -- when I've added tomatoes too soon and they remained almost chalklike. Apparently I am not alone in having experienced this.

Harold McGee's "On Food and Cooking," under the subtitle, "Cooking Legumes," notes:

Cell wall hemicelluloses are more soluble in alkaline conditions, and seeds, like stems and leaves, will soften more readily for this reason than they would in acidic water. Veteran chili makers have probably noticed this effect when they put partially cooked beans into chili sauce: the beans simply do not get any softer, no matter how long the acidic sauce is simmered (the same thing happened with baked beans; in this case, calcium ions in the acidic molasses also complex with the cell wall materials and make them even less soluble).

(From the 1984 Collier edition, page 262.)

McGee goes on to observe that this property can be put to good use in the situation where the beans are cooked perfectly, but need to be kept warm. If the environment is made acid, they will not turn to mush.

The Rancho Gordo site agrees: "If you want to add tomatoes or acids like lime or vinegar, wait until the beans are cooked through."

I suspect that the actual ingredients (age of beans + level of acidity in the tomatoes -- and canned tomatoes vary quite a bit in this regard) and ratio of beans to tomatoes to water (the alkalinity of which could vary from place to place, also affecting the effect of the acidity of the tomatoes), and one's tolerance for slightly crunchy cooked beans all figure into the equation.

If I had a bag of special beans from Greece, not easily replaced, I would not take the chance, given the unknowns involved in each of those variables. ;o)
sfmiller October 14, 2015
It's not a rumor or an old-wives tale, exactly: Acidity does make for firmer cooked beans and will prevent beans from softening, at a certain point. The practical question is, when do you reach that point?

To test this, Cooks Illustrated cooked white beans in different water+vinegar mixtures at different pH levels from 3 (strongly acidic) to 9 (mildly alkaline). Here's what they found:

"The beans cooked at a pH of 3 . . . remained crunchy and tough-skinned despite being allowed to cook 30 minutes longer than the other three batches. The beans cooked at pHs of 5, 7, and 9 showed few differences, although the 9 pH batch finished a few minutes ahead of the 7 pH batch and about 20 minutes ahead of the 5 pH batch."

Canned tomatoes have a pH of around 3.5 to 4.5, so if the cooking liquid was entirely or mostly tomatoes or also contained large amounts of vinegar or other strongly acidic ingredients, there might be a problem.

But the cooking liquid in the recipe Susan cited is mostly stock or water, whose pH is (generally) close to neutral. The beans should soften, although it might take a bit longer than if they were cooked in a non-acidic liquid.
AntoniaJames October 14, 2015
Never put tomatoes into a pot with beans until they are as soft as you want them to be. The acidity utterly and irrevocably arrests any further softening. You can cook the beans at a boil for an hour with the tomatoes and they will be just as hard.

It is not an old wives' tale. It is absolutely sound advice. ;o)
Susan W. October 14, 2015
Because this recipe is tried and true, I am going to try it. It could be the length of time in a slow cooker makes a difference. I've said it before, never stop trying or learning new things. I'll report back.
AntoniaJames October 14, 2015
Let us know how they turn out! ;o)
QueenSashy October 14, 2015
Now that you mentioned it, I think that it might have to do with food combining principles to avoid indigestion. I recall the "do not's" along the lines of "do not eat carbs and protein" and "do not eat carbs and acidic foods together". Just looked it up, here we go, beans and tomatoes is a combo to avoid
Cav October 14, 2015
Anything from a place that isn't peddling nonsense? The whole Acid-Alkaline diet is rubbish, never mind their anti-cancer diet.

Susan W. October 14, 2015
It was more of a "the beans won't cook" theory. I rarely eat beans, so the dietary warning would not have drawn my attention.

Here's one person's voice on this. If I were using a local, easy to find bean, I would just experiment, but these were sent to me from Greece.
QueenSashy October 14, 2015
Cav - please do not shoot the messenger. I just passed a link that might help explain Susan's question :)
Susan W. October 14, 2015
I appreciate your input QueenSashy. I love the sounds of this recipe, so I will carry on.
QueenSashy October 14, 2015
Susan, why do you think beans and tomatoes are "don't"? I've never heard of that... Don't people combine them all the time, e.g. chili? Or maybe I misunderstood your question.
Susan W. October 14, 2015
You know..I must go find where I got that, but I could have sworn I've read over and over not to cook dried beans with tomatoes. I don't add beans to my chili, but if I did, they would have already been cooked.
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