Does adding baking soda to soaking beans reduce gas?

I recently heard that the reason humans produce gas after eating beans is because they contain raffinose which is a starch that is poorly digested due to a lack of the enzyme galactosidase. The MD claimed that adding baking soda to the soaking liquid reduced the raffinose. Have you heard anything about this?

Vegan Epicurean / Originally posted on Beans and Gas: Clearing the Air


Yes indeed, research dating back more than 25 years (“Effect of Processing on Flatus-Producing Factors in Legumes“) found that adding baking soda to the soak water of dried beans before cooking (about 1/16 teaspoon per quart) significantly decreases the content of the raffinose family of sugars.

The study I profile here in Beans and Gas: Clearing the Air that concluded “People’s concerns about excessive flatulence from eating beans may be exaggerated” used canned beans, though, which I find to be much more convenient. If you have the time, though, it’s hard to imagine a better nutritional bargain than dried beans, peas, and lentils.

For more on the most nutrition you can squeeze out of a dollar see:

Image Credit: Grongar / Flickr


  • Billy Baker

    Recently my friend gave me a jar of Asafoetida. Using a very small sprinkling when soaking the beans apparently reduces the flatulence effect of the beans. The local Indian store may have it labeled as Hing.

    Wikipedia states this:
    Asafoetida reduces the growth of indigenous microflora in the gut, reducing flatulence.
    ^ S. K. Garg, A. C. Banerjea, J. Verma and M. J. Abraham, “Effect of Various
    Treatments of Pulses on in Vitro Gas Production by Selected Intestinal
    Clostridia”. Journal of Food Science, Volume 45, Issue 6 (p. 1601–1602).

    There is one catch, This herb is also called Devils Dung for a good reason.
    It Stinks! hoo man, it stinks. However, using a very small sprinkling and cooking the herb reduces the smell and changes it a bit. I found my self salivating when cooking the beans.

    I made up a big batch of Humus and it tasted great. No hint of the Devils dung in the
    flavor, and I must say I’m not as gassy from eating the humus.

    • Geoffrey Levens

      I love the smell of asafoetida, just be careful not to use too much or it does start to taste nasty

  • beccadog

    I found long ago that taking one Pantothenic Acid vitamins with Vitamin B and C-Complex also removed gas from various sources, including beans.
    What also works at reducing flatulence is soaking the beans over night and then cooking them in a slow cooker all day for the next meal.

    But, I’ll also store the baking soda idea in my brain.

    • outhouse1

      Soak and cook beans in ginger. Takes the farts right out.

  • Eve

    For those using canned beans, get a pressure cooker. Makes cooking beans sooo much quicker!

  • What pH is best for the soaking solution?
    ( I have caustic soda, I suppose a very small quantity will do the job )

  • Amanda Oro

    I’ve read that the lectin content in beans and other legumes makes all people intolerant to these foods and that they are inflammatory to the gut. Is this true?

    • Toxins

      Lectin and other antinutrients found in beans are eliminated with cooking. Most people consume cooked beans so this is a non issue.

      • smoothie77

        I would be interested to hear Dr. Greger’s opinion on the theory that the lectins in beans/legumes build up in the system and are what is behind the pain and discomfort that some people (including me) have experienced when eating them on a weekly (or even daily) basis.

  • Julie

    What are your thoughts about using the product Beano?

  • Thank you for the informantion!

  • Geoffrey Levens

    I find canned beans to be MORE gas producing than my own pressure cooked ones. If you soak them 8-12 hours in water, drain and rinse well, then keep them in covered container so they don’t dry out and rinse twice a day until they grow little tails (about same length as the original bean is good)(couple days depending on bean and temperature) much less gas, much easier to digest, less calories, more nutrients.

  • Kelley

    Okay here is my secret for reduced-gas beans. I soak them in distilled water for 24 hours and then let them drain, covered with a towel in a colander for 2 days, rinsing them in clean water twice a day. After three days of being damp, the beans should be sprouting anywhere from 1/4 to 1/2 inch. Something about sprouting the beans before cooking them seems to reduce the amount of gas they create after you eat them. Not all distilled waters are created equal. I have found Ozarka distilled water more effective than grocery store brand distilled water. Could be the distilling process that makes a difference?

  • Anna

    I have just been told that I should absolutely soak my grains, beans, nuts and seeds before cooking and eating them because of the phytic acid issue (and frantic googling has not helped me figuring out if this is a myth or an exaggeration or what). Can you please tell me if I should soak those things? If yes, for how long? Some sites say 24-48 hours? As a vegan, I eat a lot of those things daily. Thank you very much for your help and your great website!

    • Thea

      Anna: Based on Dr. Greger’s videos and just plain common sense (mine I guess), I don’t think it is necessary to soak before cooking. For one thing, cooking gets rid of the majority of the phytic acid. And for another thing, phytic acid may be very good for you. Check this out:

      Hope that helps.

  • seeingeye

    I’ve spent several decades of cooking and eating many kinds of beans. My method for lessening the gas-producing properties of the beans was to always add 1 tsp. baking soda to the cooking water (after soaking and pouring off the soaking water and rinsing with cold water). To prevent the taste of the soda, I also added 1 tab. granulated sugar. I always preferred to use a 6-quart heavy cast iron Dutch oven and cooked on the stove top. I never liked pressure cooked beans or slow cooked beans.

  • Violet

    I always used canned beans because of the convenience factor until I discovered how freakin’ easy it is to cook them from dried in a slow cooker. You don’t need to pre-soak them, there’s no worrying about the stove being on or anything burning etc. You just load up the slow cooker and leave it alone like a rice cooker (another godsend). AND I find the beans actually taste better, have a better texture and make me feel healthier. Personally, I don’t get gas from beans but I’ve been eating them forever. Anyways in the slow cooker I do include a little piece of ginger, so maybe that’s been helping as people have shared – though I only add it to enhance the flavor of the beans (along with a bay leaf, a halved onion and a whole garlic clove per 1 dried cup with 3 cups of water).

    I in no way sell or profit from slow cookers, I’m just so so happy that I discovered mine after 20 years of being a vegetarian (and always too lazy to cook beans from scratch)!

  • cyndishisara

    I eat one cup (dried) yielding 4 cups wet of a variety of beans per day with no gas. I wonder what my microbiome has than accomplishes the task?

  • Inna

    What about using Probiotics? Does anyone know if the gut bacteria influence gas from beans in any way?