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I let my dried beans soak too long. Are they fermented now? How bad would that be, anyway?

Okay, so I had great plans to save money by soaking and cooking my own beans. I put them in to soak, and then got super-busy and kept putting off cooking them. It has now been two days of soaking in our cool house, on the counter. Little bubbles are starting to rise from the beans, and they smell pleasantly yeasty (or something). I'm pretty much resigned to just composting them now, but I wondered if anyone had experience or knowledge about cooking possibly fermented beans. I'm tempted to do it just to find out what would happen.

Anyone know why it's supposed to be bad?

Anyone done it anyway?

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  1. That's so funny. I did the same thing this week and was going to post the same question. I gave up and threw mine out last night, but I'm interested to see if anyone has any wisdom on this.

    1. In the cookbook "Nourishing Traditions" by Sally Fallon, she recommends letting the beans soak until they sprout just a little. We've done it. Yes, it gets bubbly. You're supposed to change the water every day. I would rinse them, and cover with fresh water, and cook soon. It will be fine. The key for me in your post was that it still smells pleasant. Your nose can tell when they've gone south. This method helps get rid of the phytic acid, which blocks the absorption of some nutrients, so they're arguably better for you this way.

      1 Reply
      1. re: JGrey

        Yes, plant phytates block uptake of iron and zinc. They will have leached into the soak water: throw the water out and out go the phytates. You're probably not an anemic infant, however, so that really doesn't matter.

      2. In my experience, the yeastiness permeates the beans. Depending on your tastes, you might not find that a bad thing. I personally didn't like it so I threw it out. Since it's mainly the liquid that carries that flavor, you might want to try throwing out the soaking liquid (which many people do anyway), rinse, add fresh water, and see what happens.

        From a food safety standpoint, it doesn't seem to be much of a concern. ( I guess when you think about how many fermented products we eat, it's not a surprise :)

        1. Thanks for all the feedback. I did go ahead and cook them in fresh water last night, after rinsing them really well. I think we'll have them for dinner tonight and then monitor ourselves for interesting side effects...

          I'll let you know.

          1. Sketchy Bean Report:
            We ate delicious burritos for two days, and we're still fine. Maybe a little gassy, but that's not unusual, and not necessarily the beans. I forgot to taste the plain beans before I mixed them with spicy stuff, so I don't know if there was an off flavor.

            I wouldn't be shocked if I ended up repeating this "experiment", and if I do, I'll keep up the information gathering and reporting.

            Scatterbrains for science, unite!

            1. I was under the impression that when you soak beans, they need to be refrigerated. I'm doubting myself now, because I'd think if that were really case, someone else would have mentioned it by now...

              Anyway, Tartinet, I'm glad you avoided poisoning yourself. :)

              1 Reply
              1. re: Mawrter

                Me too! :-)

                I've heard that too about soaking. It does make sense that refrigeration would slow down fermentation, and I can't imagine it would hurt the beans. I've read everything from "always refrigerate" to "refrigerate in warm weather" to "refrigeh-wha?" from various seemingly worthy sources. So who knows.

                I'm living proof of only one thing: at the very least, eating slightly fermented beans isn't fatal 100% of the time. Beyond that, who can say? We need ATC or Steingarten to do some research, although I'm not holding my breath. It's not the sexiest topic.

              2. Soaking unrefrigerated beans until fermentation serves to break down some of the polysaccharides that can contribute to "social distress." Let the soaking pan do some of the pooting for you, I always say.

                Rather than the effete ATK, we could use the input of some ethnobotanists/anthropologists who have tracked down soaking traditions back at least 100 years by those cultures that overwintered on stockpiled beans. Of course they did not refrigerate, but to what extent did they rinse or decant to strike that balance between fermentation and viable sprouting?

                1 Reply
                1. re: FoodFuser

                  >> Let the soaking pan do some of the pooting for you, I always say.

                  LOL Yes, and it avoids having your better half blame the dogs...

                2. Wow, you really can Google almost anything! I typed in "soaked beans too long" and got to this post. I've currently got some fermented-bean soup simmering and couldn't decide whether to eat it, but now I think I'll give it a try.

                  1. I have given up soaking beans. Several years ago I tried a new method.
                    Cover with water by about 3 or 4 inches. Slowly bring to boil. Let boil gently for 20 minutes. Turn off heat. Cover. Let stand 20 minutes. Discard the water. Repeat and then continue with your project. It substitues for soaking and it degasses the beans besides.

                    1. Rick Baylass and Diana Kennedy recommend that you don't soak your beans before cooking. I have cooked beans that have been soaked, ones that were given the quick boiling soak and also ones that were not soaked at all. The beans with the best flavor were the ones that were not soaked at all ( and they didn't take much more time to cook).

                      1. I typed in google "soak beans 2 days safe"... I kept putting off cooking my black beans, and have frequently change the water and left soaking in the fridge for 2 days. I feel safe to cook now, after reading all your replies. I was gonna bake it with bread but now i'm just gonna steam it with jasmine rice and shitake mushroom in a claypot for a quick lunch.

                        1. I soaked my garbanzo beans for 2.5 days with whey. I put off cooking them, so I let them sit out a little, and they started smelling sour. After I discarded the liquid and put a little salt, they smelled ok. I kept them in the refrigerator for 3 days. The skins felt a little slimy so I peeled the skins off. I boiled them, tasted some, taste a little sour. I know fermented foods can have a little sour taste, and I don't mind as long as they're not bad. How can I tell? Should I just throw it out, or is there something you can do with sour fermented garbanzo beans?

                          1. similar situation - cannellini beans, soaked for 2 and a half days (outside of the fridge! with no water changes!) - but... no weird colors and hardly any foam, just kind of stinky. After water change and boiling they still smelled and tasted a little off, but I referred to this thread at that point and tried to go with the "fermented stuff is healthy" approach and see if I could make it palatable.

                            My original plan for the beans was either a white bean soup or a bean/tuna/basil/olive oil salad, but I wasn't going to enjoy either of those if the beans were going to retain their slightly funky flavor. Although I've never had natto before, I figured I'd go in that general direction and cooked the beans down some more, added a little carrot for variety, and masked the funk with curry (S&B, the curry roux). I had this over soba, and a couple days later, over rice, with no ill effects - yay! (and it tasted good too)

                            good luck to everyone else with overly-soaked beans...

                            2 Replies
                            1. re: skayam

                              you guys ROCK been soaking my peas for 2 days am about to crockpot ham and split pea was a litte leary and a littlle drunk so thanki you for good advice

                              1. re: wannie20

                                My son and I have a bowel/gas/cramps long medical history. We both have had serious enough bowel issues there had to be some changes in our diets. Beans, Chickpeas, ect. I don't soak then amymore for the "suggested amount of time." I now soak them 2-3 days rinsing before even thinking of using them. It really helps on the tummy problems. Not only that, but they have WAY LESS sodiumi. Eating beams soaked makes them less gassy, and able to be digested without all them gproblems.

                            2. Can I say - I feel I have found my people!
                              How often do I actually cook the soaked beans within the intended amount of time? Hardly ever, and after years of cooking up batches of two+ days of soaked beans, even I became fearful of how long things had gone on for.... I forgot about those beans for at least 3 days, but honestly, lets just call it 4. Foam topped black beans for dinner??? Yes, actually!
                              After reading this thread I threw some gas under that pot o black beans and went for it - (After changing water and rinsing, and changing the water again, and rinsing!!)
                              There was a little more scum in the cooking water than usual, but apart from that, nothing.... Don't think any of us were more or less gassy than usual, and the beans seemed like, beans. I do add a lot of spices, but before I did I made sure I taste tested one naked, and it was fine.
                              This is the first forum I have ever posted in, or probably ever will, let it be known you moved me, you well intended but not quite together bean eaters... Lets make it work in our own time!

                              1. For the record, You could have just drained them and frozen them in a ziploc bag and then when you had time proceeded cooking them as pre soaked.

                                Do it all the time.

                                1 Reply
                                1. re: hyde

                                  I did the same thing with my Garbanzo beans....i was trying to sprout them, but instead just fermented them, because it is summer and humid at the moment. My husband wanted to throw them out because they smelled like yogurt, but I insisted fermented food are generally good for you. I boiled them until they softened a bit more (took longer than I thought...at least 2 hours) then realized that the health benefits of the fermentation process would be negated by boiling...but after reading this I am not so sure...any way I made a tasty salad of them with spinach, oil, lemon, garlic, chives and other herbs and spices. It is pretty tasty and no ill side effect yet to note.... I'll keep you posted.

                                2. Same thing happened to my northern beans I soaked for 2 days. I rinsed them in fresh water as reccomended then I used a little bit of vinegar in the fresh water with them to kill that horrid smell. Rinsed them again & used fresh water In my crockpot with my sautéed onions ham & lots of salt & pepper and the smell is already gone & yummy ham & beans are Cookin!

                                  1 Reply
                                  1. re: megz87

                                    I'm trying your vinegar idea on my northern beans that were soaking for two days. They smell better already and they're going into the crockpot as planned. I call these things science experiments if they go bad, but y'all give me hope here.

                                  2. I soaked mine for three days. The kitchen was smelling a little sour. My son is super sensitive to legumes and gets gas excessively. Soaked partially fermented beans are the only ones that do not give him gas. Usually I let them soak in the refrigerator but didn't this time, just Because. They are a tad bit sour but I'm going to see how we like them. We've never gotten sick from soaking beans. I prefer overly soaked beans to unsoaked. Phytic acid is not good for optimum stomach health.

                                    I usually cool them in a crock pot with a beef bone.

                                    1. thanks for all the good info...scanned through everyones post...I've got 3#'s of beans been soaking for about 36 hrs...full house of ppl but trials, tribulations, and work don't stop so that beans can get cooked. I came home yesterday from work in hope that someone had the beans cooking. Nope. I will rinse before work this morn, and get someone cooking them today while I work. Then after work hopefully we'll have beans, rice, & cornbread, then head to church. Yeppers, funny what things you find when you just typing something on the address line...Have a blessed day!