What ingredients should I avoid in low FODMAP sourdough?

January 5, 2026 •

3 min read

Over 1 in 10 people worldwide suffer from Irritable Bowel Syndrome (IBS), a condition where certain carbohydrates, known as FODMAPs, can trigger uncomfortable symptoms. Knowing what ingredients should I avoid in low FODMAP sourdough is essential for bakers managing these sensitivities.

Quick Summary

This article details the high-FODMAP ingredients to eliminate from sourdough recipes for better digestive health. It covers high-FODMAP flours, sweeteners, and additives, and outlines safer alternatives to ensure your sourdough is tummy-friendly.

Key Points

Avoid high-FODMAP flours: Eliminate rye, kamut, and barley flour due to high fructan content, even after fermentation.
Use low-FODMAP flour alternatives: Opt for long-fermented spelt, certified gluten-free blends, rice flour, or sorghum flour for safer results.
Check for high-FODMAP sweeteners: Scrutinize ingredient lists for honey, agave, and high-fructose corn syrup.
Exclude high-FODMAP additives: Avoid flavorings like onion and garlic, which are often found in savory breads and contain fructans.
Emphasize a long fermentation process: Ensure your sourdough ferments for at least 12-24 hours, as this is how the FODMAP-reducing bacteria and yeasts work.
Read all labels carefully: When purchasing pre-made bread, always check the ingredients for hidden sources of FODMAPs, like inulin.
Start your own starter: Consider making your own low-FODMAP sourdough starter with appropriate flours for full control.

High-FODMAP flours to eliminate

The primary source of FODMAPs in many traditional sourdough recipes is the flour itself. The 'O' in FODMAP stands for oligosaccharides, which include fructans—a type of carbohydrate found in abundance in certain grains. While the sourdough fermentation process can significantly reduce the fructan content in some flours, it may not be enough for highly sensitive individuals. For this reason, it's safest to completely avoid certain flours during the elimination phase of the low FODMAP diet.

Rye flour: Rye is notoriously high in fructans and should be strictly avoided. Unlike wheat, the fermentation process doesn't reduce the fructan content of rye enough to be considered low FODMAP.
Kamut (Khorasan) flour: This ancient grain, while often viewed as a healthier alternative, is high in fructans and should be avoided.
Barley flour: Barley is also high in fructans and is not suitable for a low FODMAP diet.
Standard wheat flour (in large quantities): While long-fermented wheat sourdough can be low FODMAP in smaller servings, commercial or quick-fermented wheat sourdough might not be suitable. It's crucial to check serving sizes and fermentation times, but many find it easier to switch to alternative flours.

Safer low-FODMAP alternatives

For those seeking to bake low FODMAP sourdough, several flours are naturally lower in fructans or are more easily tolerated.

Spelt flour: Traditional, long-fermented spelt sourdough has been tested by Monash University and found to be low FODMAP in specific serving sizes. The natural fructan content is lower than modern wheat, and fermentation further reduces it.
Certified gluten-free flour blends: Using a certified gluten-free, low FODMAP flour blend is a surefire way to avoid grain-based fructans. Many blends use a combination of low-FODMAP flours like rice, sorghum, and potato starch.
Rice flour: A popular and versatile option for gluten-free baking, rice flour is naturally low FODMAP.
Sorghum flour: This mild-flavored, gluten-free flour is another excellent low-FODMAP choice.

High-FODMAP sweeteners and additives

Beyond the flour, many common additions to sourdough can contain hidden FODMAPs. It is important to scrutinize every ingredient and its source to ensure compliance.

Honey and agave: Both are high in FODMAPs, specifically excess fructose in honey and fructans in agave.
High fructose corn syrup (HFCS): As the name suggests, this is high in fructose and should be avoided.
Inulin or chicory root fiber: These are frequently added to fiber-enriched breads and are high in fructans.
Onion or garlic: These are common flavor additions in savory breads but are high in fructans. Be sure to avoid any pre-made sourdoughs that list these as ingredients.

Other considerations for low FODMAP sourdough

Even with the right ingredients, preparation matters. The key to successful low FODMAP sourdough is the fermentation process itself. Longer fermentation times (often 12-24 hours) allow the sourdough starter's bacteria and wild yeast to consume more of the fructans present in the flour, even in those made with wheat or spelt. Ensure you are using a slow, traditional fermentation method rather than a quick-rise approach.

Comparing flours for low FODMAP sourdough


Feature	Traditional Wheat Flour	Long-Fermented Spelt Sourdough	Certified Low FODMAP GF Blend
Primary FODMAP	Fructans (high)	Fructans (lower than wheat)	None (eliminates fructans)
Low FODMAP Serving Size	Small, if traditionally fermented	Larger (approx. 2 slices)	Larger (depends on blend)
Flavour	Classic, chewy bread texture	Mild, nutty flavour	Varies by brand; often mild
Baking Complexity	Standard, but fermentation crucial	Slightly more challenging than wheat	Often requires specific instructions

Conclusion

Successfully baking low FODMAP sourdough requires careful attention to both ingredients and process. By avoiding high-FODMAP additions like rye, barley, certain sweeteners, and common seasonings, and by selecting safer flours like spelt or certified gluten-free blends, you can create a gut-friendly loaf. Remember that the length of fermentation is a key factor in reducing FODMAPs, so patience is a critical ingredient in your low FODMAP baking journey. Always reference reliable sources like the Monash University FODMAP app for the latest tested information.

Frequently Asked Questions

You should avoid flours high in fructans, such as rye, kamut (Khorasan), and barley. While fermentation reduces FODMAPs in some flours, these remain high-risk.

Yes, long-fermented spelt sourdough has been tested and found to be low FODMAP in certain serving sizes, as the fermentation process breaks down the fructans.

Yes, avoid sweeteners like honey, agave, and high fructose corn syrup, as they are high in FODMAPs.

A longer fermentation time, typically 12-24 hours, allows the natural bacteria and wild yeast in the starter to consume more of the fructans in the flour, reducing the overall FODMAP content of the finished bread.

No, commercial bakers yeast is considered low FODMAP itself. The key factor for low FODMAP sourdough is the starter and long fermentation process, not the addition of commercial yeast.

You can use a wheat-based starter, but the crucial step is the long fermentation of the final dough. The extended fermentation process breaks down the fructans in the wheat flour, making it low FODMAP in moderate servings.

No, not all gluten-free flours are low FODMAP. Some, like coconut flour or chickpea flour, can be high in FODMAPs. Always check the specific flour or blend using the Monash University FODMAP app.