How do they put fiber in soda?: The Science Behind Prebiotic Drinks

November 3, 2025 •

5 min read

With the daily recommended fiber intake increasing, more companies are developing functional beverages to help consumers meet their nutritional goals conveniently. This trend has led to the rise of prebiotic sodas, but how do they put fiber in soda without altering its taste or texture? The process involves using specific types of highly-soluble, plant-based fibers that dissolve completely in liquid.

Quick Summary

This article explores the food science behind fiber-fortified sodas. It details the soluble fibers used, including inulin and corn fiber, how they are processed, and the benefits they offer for gut health. It also compares fiber-enhanced drinks with traditional fiber sources.

Key Points

Soluble Fiber is Key: Manufacturers use specific types of soluble fibers, like inulin and soluble corn fiber, that dissolve completely in liquid, avoiding any gelling or thickness.
Common Fiber Sources: Inulin is often sourced from chicory root or agave, while soluble corn fiber is created from cornstarch.
Preserving Sensory Qualities: A major goal of the manufacturing process is to ensure the added fiber does not alter the soda's taste, color, or texture.
Prebiotic Benefits: The soluble fibers in these sodas act as prebiotics, feeding beneficial bacteria in the gut and promoting a healthy microbiome.
Not a Replacement for Whole Foods: While beneficial, fiber-fortified sodas should not replace the diverse range of fibers and nutrients obtained from whole fruits, vegetables, and grains.
Processing Ensures Stability: Food scientists use processes like homogenization and pasteurization to ensure the fiber is evenly distributed and the product remains stable over its shelf life.
Watch for Digestive Effects: Some individuals may experience gas or bloating when first incorporating prebiotic sodas into their diet.

The Core Principle: Using Soluble Fiber

When people think of fiber, they often imagine insoluble fibers like psyllium husk, which swells and forms a gel in water. This would result in a thick, unpalatable soda. To avoid this, manufacturers exclusively use soluble fibers that can dissolve completely in the beverage's liquid base. This is the key technological hurdle to overcome: adding a health-boosting ingredient without compromising the expected sensory experience of a refreshing, fizzy drink. These specialized soluble fibers are often extracted and processed into a form that is both tasteless and colorless.

Key Types of Soluble Fibers Used

Several types of soluble fibers are suitable for use in clear beverages like soda, each with slightly different properties.

Inulin: One of the most common prebiotic fibers, inulin is a naturally occurring polysaccharide derived from plants like chicory root or agave. It's a popular choice because it has a slightly sweet taste and dissolves easily, contributing a creamy mouthfeel without adding significant calories. As a prebiotic, it ferments in the colon, feeding beneficial gut bacteria.
Soluble Corn Fiber: Also known as resistant maltodextrin, soluble corn fiber is a non-digestible carbohydrate produced from cornstarch. It is highly soluble, heat-stable, and has minimal impact on the beverage's flavor or color. It is often used to add fiber content and replace sugars.
Gum Acacia: Also called gum Arabic, this natural gum is a soluble fiber sourced from the acacia tree. It is highly soluble and has been shown to support digestive health. It's a low-viscosity option that can be used at higher levels without negatively impacting the texture of the soda.
Guar Gum: Partially hydrolyzed guar gum is another soluble fiber that can be mixed into beverages. It acts as a thickener and stabilizer but, in its hydrolyzed form, can be used to add fiber without significantly affecting viscosity.

The Manufacturing Process

The process of adding fiber to soda is a precise and carefully controlled industrial procedure. The goal is to ensure the fiber integrates seamlessly and remains stable throughout the product's shelf life.

Sourcing and Extraction: Manufacturers begin by sourcing the raw plant materials, such as chicory root or cornstarch. Specialized processes like enzyme-based hydrolysis are used to extract and purify the soluble fiber, isolating it from other components of the plant.
Formulation: The purified fiber, typically in a powdered or liquid concentrate form, is blended with the other soda ingredients. This includes the water base, sweeteners (often low-calorie to complement the fiber's benefits), flavorings, and any other additives.
Homogenization and Pasteurization: To ensure a consistent product and prevent the fiber from settling, the mixture is homogenized. It is then pasteurized to eliminate any potential harmful microorganisms, ensuring product safety and stability.
Carbonation and Packaging: The final step involves carbonating the beverage to give it its signature fizz. The product is then packaged into bottles or cans, ready for distribution. Throughout this process, quality control checks are performed to ensure the fiber does not negatively affect the soda's taste, clarity, or texture.

Fiber-Fortified Soda vs. Traditional Fiber Sources

While fiber-fortified soda offers a convenient way to boost fiber intake, it's important to understand how it compares to getting fiber from whole foods.


Feature	Fiber-Fortified Soda	Whole Foods (e.g., Vegetables, Legumes)
Fiber Type	Contains isolated, soluble fibers (e.g., inulin, corn fiber).	Contains a mix of both soluble and insoluble fibers.
Nutrient Content	Primarily provides isolated fiber and may include added vitamins, but lacks the broad range of nutrients found in whole foods.	Rich in a variety of vitamins, minerals, and other phytonutrients in addition to fiber.
Sensory Experience	Designed to be tasteless and not alter the drink's texture.	Contributes significant texture and flavor to meals.
Digestive Impact	Prebiotic fibers feed gut bacteria, which can cause gas and bloating for some individuals.	May also cause initial digestive adjustments, but the combination of fiber types generally supports overall digestive regularity.
Satiety	Can contribute to a feeling of fullness, aiding in weight management.	Promotes a stronger and more sustained feeling of fullness.
Context	An easy on-the-go supplement but should not be a primary source of nutrition.	A fundamental part of a healthy, balanced diet.

The Role of Soluble Fiber in Gut Health

The primary motivation behind adding fiber to soda is to leverage the gut health benefits of prebiotic soluble fiber. These non-digestible components travel to the large intestine, where they are fermented by beneficial gut bacteria. This fermentation process supports the growth of a healthy gut microbiome, which has numerous downstream effects on overall wellness, including improved digestion, nutrient absorption, and immune function. The appeal of prebiotic sodas is the ability to obtain these benefits from a familiar and enjoyable beverage.

Potential Downsides and Considerations

While the concept is promising, there are considerations consumers should keep in mind.

Digestive Discomfort: For some people, a sudden increase in fiber intake, particularly from fermented fibers like inulin, can lead to bloating, gas, and stomach cramps. This is particularly true for individuals with conditions like Irritable Bowel Syndrome (IBS).
Does Not Replace Whole Foods: Health experts emphasize that fiber-fortified drinks should be viewed as a supplement, not a replacement for the fiber and nutrients found in whole foods like fruits, vegetables, and legumes.
Ingredient Check: While many prebiotic sodas are low in sugar, some may contain other artificial ingredients or sweeteners. It is always wise to read the ingredients list to ensure the product aligns with your overall dietary goals.

Conclusion

The science behind adding fiber to soda is a testament to modern food technology, focusing on isolated soluble fibers like inulin and soluble corn fiber. These ingredients are carefully processed and blended to create a beverage that delivers a dose of fiber without compromising the desired taste and texture. While these drinks offer a convenient way to boost prebiotic intake and support gut health, they are best enjoyed as a supplement to a diet rich in diverse, whole food sources of fiber. For those seeking to enhance their gut health through beverages, they provide an interesting and accessible option.

For more information on the science of functional foods, check out this guide on the topic.

Frequently Asked Questions

The fiber used in sodas is a type of soluble fiber, which dissolves completely in water. Common examples include inulin, which comes from chicory root or agave, and soluble corn fiber, derived from cornstarch.

You don't notice the fiber because it is a soluble, purified form that completely dissolves during the manufacturing process. Unlike insoluble fibers (like psyllium husk), it does not create a thick or gelatinous texture.

The primary benefit is for gut health. The soluble fiber, which acts as a prebiotic, feeds the good bacteria in your gut, supporting a healthy microbiome, improved digestion, and regular bowel movements.

No, health experts recommend that fiber-fortified drinks should be used as a supplement, not as your main source of fiber. Whole foods like fruits, vegetables, and grains provide a greater variety of fiber types and nutrients.

Prebiotic soda is generally considered a better option than traditional sugar-laden soda because it contains less sugar and offers gut health benefits from the added fiber. However, it's not a substitute for a balanced diet.

Yes, some people may experience digestive discomfort, such as gas or bloating, when they first start consuming prebiotic fibers. This is especially true for individuals sensitive to FODMAPs.

The fiber is typically added in a concentrated powder or syrup form during the formulation stage. It is blended with water and other ingredients before being homogenized, pasteurized, and carbonated.