Does Putting Baking Soda in Beans Prevent Gas?

November 30, 2025 •

4 min read

According to research from the 1980s, adding baking soda to the soaking water of dried beans can significantly decrease the content of raffinose and stachyose, the gas-causing sugars. This simple kitchen trick—putting baking soda in beans—works by creating an alkaline environment that helps break down these complex sugars, which are notoriously difficult for the human digestive system to process.

Quick Summary

This article examines the efficacy of adding baking soda to beans to reduce intestinal gas. We detail the scientific mechanism behind this folk remedy, explain why beans cause bloating, and provide alternative cooking methods that promote better digestion and reduce flatulence.

Key Points

Baking soda works by breaking down sugars: Adding baking soda to bean soaking water creates an alkaline environment that breaks down the complex sugars (oligosaccharides) responsible for gas.
Soaking and rinsing is critical: The key to success is discarding the soaking water, which now contains the gas-causing sugars, and rinsing the beans thoroughly before cooking.
Speed and texture benefits: Baking soda also accelerates cooking time and can lead to a creamier, softer bean texture.
Don't overdo it: Using too much baking soda can result in a soapy flavor and mushy beans, so use it sparingly.
Alternative methods exist: Other options for reducing gas include using a digestive enzyme supplement like Beano, pressure cooking, or gradually increasing your bean intake.
Adaptation is a factor: Your body and gut microbiome can adjust to higher bean consumption over time, reducing symptoms of gas and bloating.

The Science Behind Bean-Induced Flatulence

Beans, like many other legumes, contain complex sugars called oligosaccharides, including raffinose and stachyose. The human body lacks the enzyme, alpha-galactosidase, necessary to break down these sugars in the small intestine. As a result, the oligosaccharides travel to the large intestine where they are fermented by gut bacteria, producing gases such as hydrogen, carbon dioxide, and, in some people, methane. This fermentation process is the direct cause of the bloating and flatulence many people experience after eating beans. While it can be uncomfortable, this gas production is a sign that beneficial gut bacteria are being fed, which is a positive aspect for gut health.

How Baking Soda Reduces Gas in Beans

Baking soda, or sodium bicarbonate, is an alkaline substance that raises the pH of water. When a small amount is added to bean soaking or cooking water, it creates a more alkaline environment. This alkalinity helps to break down pectin, a compound in the cell walls of the beans, which in turn allows the gas-causing oligosaccharides to leach out into the water.

Enhanced Sugar Removal: Soaking beans in water with baking soda helps leach out more of the problematic oligosaccharides than soaking in plain water alone. Discarding and rinsing the beans after this process is crucial for removing the sugars that have seeped out.
Accelerated Cooking: The alkaline environment also speeds up the cooking time of the beans, allowing them to soften much more quickly.
Softens Bean Texture: By weakening the cell walls, baking soda helps produce a creamier, softer bean texture. However, adding too much can make the beans mushy and give them a slightly soapy flavor, so moderation is key.

Alternatives to Baking Soda

While baking soda is an effective method, it is not the only way to reduce the gas-producing effects of beans. There are several other strategies that can be used, both with and without the addition of baking soda.

Comparison of Gas-Reduction Methods


Method	How It Works	Pros	Cons
Baking Soda Soak	Alkaline water helps break down oligosaccharides and pectin.	Effective at reducing gas and speeding up cooking.	Can affect flavor and texture if too much is used; increases sodium content.
Prolonged Soaking	Soaking beans in plain water for 8-12 hours allows some oligosaccharides to dissolve into the water.	Simple, no additives required.	Less effective than methods using baking soda or other supplements.
Digestive Enzymes (e.g., Beano)	Contains the enzyme alpha-galactosidase, which breaks down the oligosaccharides in the digestive tract.	Extremely effective when taken before a meal containing beans.	Requires taking a supplement; does not alter the food itself.
Pressure Cooking	The high heat and pressure break down the oligosaccharides and soften beans rapidly.	Very effective and fast method.	Requires specialized equipment.
Gradual Introduction	Allows your gut microbiome to adjust to and better digest the oligosaccharides over time.	Natural, long-term solution.	Takes time; discomfort may occur during the adjustment period.
Adding Herbs & Spices	Certain herbs like epazote and spices like cumin can aid digestion.	Adds flavor while potentially easing digestion.	Effects can vary and are often less pronounced than other methods.

Step-by-Step Guide to Using Baking Soda with Beans

Rinse and Sort: Start by picking through your dry beans, removing any pebbles or debris. Rinse them thoroughly under cold running water.
Add Baking Soda: For every cup of dried beans, add about 1/8 to 1/4 teaspoon of baking soda to a large pot with water, ensuring the beans are covered by at least two inches.
Soak Overnight: Let the beans soak for 8 to 12 hours. This gives the baking soda time to work its magic and helps break down the sugars.
Drain and Rinse (Crucial Step): This is the most important step for reducing gas. Discard the soaking water entirely and rinse the beans thoroughly under fresh water. This washes away the gas-causing oligosaccharides that have leached out.
Cook as Desired: Add fresh water and cook the beans according to your recipe. Adding acidic ingredients like tomatoes at this stage, after the beans have softened, is recommended as acid can inhibit the softening process.

Conclusion: The Final Verdict

Yes, putting baking soda in beans does help prevent gas, and this isn't just an old wives' tale; it's supported by food science. The mildly alkaline sodium bicarbonate helps break down the complex, gas-causing sugars known as oligosaccharides, which are otherwise fermented by gut bacteria. By soaking the beans in a baking soda solution and then thoroughly rinsing them, you can significantly reduce the potential for flatulence and bloating. However, it is not a cure-all, and results can vary depending on the individual's gut microbiome and other preparation techniques. For a truly comprehensive approach to enjoying beans without discomfort, a combination of methods—such as soaking with baking soda, rinsing well, and eating them consistently—is often the most effective strategy.

The Role of Gut Adaptation

Beyond cooking techniques, it is important to understand that your gut adapts over time. Studies have shown that for people who are not regular bean-eaters, initial gas and bloating may be noticeable, but as you continue to consume beans regularly, your digestive system, particularly the gut microbiome, will adjust. The gas-producing bacteria are fed and over time, the body becomes more efficient at processing the fibrous compounds. So, consistency in eating beans can build up your body's tolerance and reduce future discomfort.

Visit The Bean Institute for more information on the health benefits and preparation of legumes.

Frequently Asked Questions

The primary cause of gas from beans is the presence of oligosaccharides, complex sugars that the human body cannot fully digest due to a lack of the necessary enzyme. Gut bacteria ferment these sugars in the large intestine, producing gas as a byproduct.

For soaking dried beans, it is generally recommended to add a small amount, such as 1/8 to 1/4 teaspoon of baking soda per cup of beans. Using more than this can negatively impact the flavor and texture.

While both methods can reduce gas, soaking with a small amount of baking soda is more effective at breaking down the oligosaccharides and speeding up the cooking process compared to soaking in plain water alone.

Yes, rinsing canned beans is highly recommended. The oligosaccharides leach into the canning liquid, so draining and rinsing the beans removes many of these gas-causing compounds.

Effective alternatives include using a digestive enzyme supplement (e.g., Beano), cooking beans in a pressure cooker, gradually increasing your intake to build tolerance, or adding digestive-aiding spices like cumin.

Adding acidic ingredients like tomatoes too early can slow the softening of the beans and potentially affect the effectiveness of other methods. Salt does not directly impact gas production but can affect bean texture.

Yes, studies have shown that consistently eating beans can allow your gut microbiome to adapt, which may lead to reduced gas and discomfort over several weeks.