What Cheese Has L. reuteri? Understanding Probiotic Dairy Options

A 2023 study highlighted the successful development of a psychobiotic-containing quark-type cheese fermented with Limosilactobacillus reuteri, demonstrating that while most conventional cheeses lack this specific probiotic, functional products can be created. This makes finding what cheese has L. reuteri a search for engineered, not naturally-occurring, products.

Quick Summary

Most conventional cheeses do not naturally contain the probiotic L. reuteri due to specific fermentation and aging processes. This beneficial bacteria is primarily found in specialized functional cheeses made with adjunct cultures, specific homemade preparations like kefir cheese, or dietary supplements. It is not reliably present in standard commercial cheese varieties.

Key Points

• Not in Conventional Cheese: Traditional, mass-produced cheeses do not reliably contain L. reuteri due to pasteurization and the specific conditions of commercial aging.

• Engineered Functional Foods: Specialized probiotic or "functional" cheeses are made by adding L. reuteri as an adjunct culture, as demonstrated in studies with Feta and quark-type cheeses.

• Fresh Cheese Best Carrier: Research indicates that fresh, un-aged cheese provides a more viable environment for L. reuteri than aged varieties, which have higher acidity and salt content.

• Homemade Probiotic Cheese: Making cheese from an L. reuteri yogurt starter or milk kefir allows you to create your own reliable source at home, such as L. reuteri cottage cheese.

• Supplements Offer Highest Reliability: For guaranteed potency and specific strains like DSM 17938, dietary supplements are the most reliable source, surpassing the variable content in most fermented foods.

• Check Labels and Product Info: To find L. reuteri in cheese, you must look for products specifically labeled as probiotic or functional, rather than assuming its presence in standard varieties.

• Strain-Specific Effects: The health benefits of L. reuteri are strain-specific. Always check the labels for the exact strain used, especially in supplements, for targeted effects like gut or brain health.

The Surprising Truth About L. reuteri in Cheese

Many consumers seeking to incorporate beneficial probiotics into their diet often look towards fermented foods like cheese. While many cheeses do contain various strains of lactic acid bacteria (LAB) from their starter cultures, the specific strain Lactobacillus reuteri is not a common resident of traditional, mass-produced cheese. The vast majority of cheeses available in supermarkets are not reliable sources of L. reuteri.

The search for L. reuteri in cheese leads down a path of specialized applications rather than natural occurrence. This probiotic is typically found in supplements and certain fermented dairy products like yogurt, where its concentration and viability can be carefully controlled. However, innovative food science has led to the creation of specific "functional" cheeses where L. reuteri is deliberately added.

Why Most Cheeses Don't Naturally Contain L. reuteri

The reason L. reuteri isn't prevalent in aged, store-bought cheese lies in the production process itself. Several factors inhibit the growth and survival of many probiotic strains, including L. reuteri, in a standard cheese matrix:

• Low pH and Salt Content: As cheese ripens, the pH drops and the salt content increases, creating a harsh environment where only certain robust bacteria can survive. Many probiotic strains, including L. reuteri, see a significant reduction in their population over the aging period.
• Specific Starter Cultures: The microorganisms used to create traditional cheeses, like Cheddar or Gouda, are specifically chosen for their role in flavor and texture development. These standard starter cultures do not include L. reuteri.
• Pasteurization: Most commercially available cheese is made from pasteurized milk, which kills all microorganisms, including any naturally occurring L. reuteri that may have been present.

Engineered Probiotic Cheeses with L. reuteri

For consumers who want to consume L. reuteri specifically in a cheese format, the market for functional foods is where to look. Food scientists have developed methods to incorporate viable L. reuteri strains into cheese by using it as an adjunct culture, meaning it is added in addition to the standard starters. Studies have shown that this can be a successful way to produce probiotic cheese:

• Feta Cheese: Research has demonstrated the successful creation of a Feta-type cheese made with buffalo milk where a local strain of L. reuteri was added as an adjunct culture. This cheese maintained high counts of viable L. reuteri throughout its ripening period.
• Fresh Cheese: A study exploring the development of a Serbian quark-type cheese used L. reuteri DSM 17938 as a fermenting agent. The resulting product successfully retained high viability of the psychobiotic strain. This suggests that fresh, less-aged cheeses are a particularly good matrix for carrying this probiotic.
• Semi-Hard Cheese: In some studies, L. reuteri has been used to create semi-hard ewe's milk cheese, showcasing its potential in various cheese types, though its survival rate can vary with aging conditions.

Creating Your Own L. reuteri Cheese at Home

For those who enjoy a DIY approach, it is possible to make your own probiotic cheese using a high-potency L. reuteri starter culture. One popular method involves making yogurt cheese from homemade L. reuteri yogurt. This process concentrates the probiotic bacteria and results in a soft, spreadable cheese.

Steps for Making Homemade L. reuteri Yogurt Cheese:

1. Prepare the Yogurt: Start by making a batch of L. reuteri yogurt using a specific starter culture and milk. Incubation typically takes 24 to 36 hours at a consistent temperature to maximize probiotic counts.
2. Strain the Yogurt: Once the yogurt is fermented, strain it through a cheesecloth or fine mesh strainer. This process, which can take several hours, separates the whey from the thick yogurt curds.
3. Flavor and Store: The resulting thick, creamy curds are your yogurt cheese. You can add salt, herbs, or other flavorings. This homemade cheese should be stored in the refrigerator and consumed within a couple of weeks.

Comparison of L. reuteri Sources

Source	Processing Method	L. reuteri Content	Reliability	Ideal For	Notes
Conventional Cheese	Standard Fermentation/Aging	None or negligible	Very Low	Flavor only	Processing kills most probiotics; not a source of L. reuteri.
Functional Probiotic Cheese	Adjunct Culture	High (Specific Strains)	High	Targeted health benefits	Made by specific food manufacturers; check labels for strains.
Homemade Kefir Cheese	Kefir Grain Fermentation	Moderate to High	Medium	DIY/Home enthusiasts	Content can vary; depends on kefir grains and process.
Homemade L. reuteri Yogurt Cheese	Specific Culture Incubation	High	High	Home-based probiotic control	Requires a specific starter culture for guaranteed content.
Probiotic Supplements	Laboratory Controlled	High (Specific Strains)	Very High	Consistent dosing	Best for guaranteed, high-potency probiotic intake.

Conclusion

In summary, the short answer to "what cheese has L. reuteri?" is that conventional, store-bought cheese is not a source. Most cheeses contain different bacteria, and the conditions of commercial aging and pasteurization are not conducive to L. reuteri survival. However, for those interested in adding this beneficial strain to their diet through dairy, there are two reliable pathways: seeking out new functional food products specifically engineered with L. reuteri or embarking on a homemade cheese-making adventure using a specialized starter culture. For maximum potency and consistency, supplements remain the most dependable source, but fresh, functional cheeses offer a promising food-based alternative for specific health goals. Learn more about probiotic strains in cheese from the NIH.

References

• NIH: PMC.nih.gov.
• ResearchGate: ResearchGate.net.
• Cultured Food Life: Culturedfoodlife.com.
• MDPI: MDPI.com.
• Wellgard: Wellgard.co.uk.
• Keystone Cheese: Keystonefarmscheese.com.
• Revolution Fermentation: revolutionfermentation.com.
• Healthpath: Healthpath.com.

---

This content was created based on information available as of October 2025. Always check product labels for specific probiotic strains and consult a healthcare professional for dietary advice.

Frequently Asked Questions

What kind of cheese is a good source of probiotics?

While many cheeses contain some lactic acid bacteria, the most reliable sources of probiotics are fresh, soft cheeses like quark or kefir cheese specifically made with a probiotic starter. Aged cheeses are generally not a good source of viable probiotics.

Why is L. reuteri not found in most standard cheese?

Commercial cheese production often involves pasteurization, which kills live bacteria, and aging processes that create a high-salt, low-pH environment unfavorable for many probiotic strains like L. reuteri.

Can I make my own L. reuteri cheese at home?

Yes, you can make your own L. reuteri cheese at home by using a specific starter culture to ferment milk into yogurt and then straining it to create a thick yogurt cheese.

Does aged cheddar or Swiss cheese contain L. reuteri?

No, aged cheeses like cheddar and Swiss do not contain L. reuteri. While they contain other bacterial strains, the harsh aging conditions mean L. reuteri would not survive.

What is a 'functional' probiotic cheese?

A 'functional' probiotic cheese is a product where a specific probiotic strain, like L. reuteri, is intentionally added during the production process to confer health benefits. These are distinct from traditional cheeses.

Is kefir cheese a good source of L. reuteri?

Kefir cheese can be a source of L. reuteri if the milk kefir used was made with grains that specifically contain this strain. However, the probiotic content can vary depending on the grains and fermentation process.

What is the most reliable source for L. reuteri?

For consistent and high levels of L. reuteri, dietary supplements with specific, tested strains (e.g., DSM 17938) are the most reliable source. Some commercially available yogurts may also contain it.

How do food scientists add probiotics to cheese?

Food scientists can add probiotics to cheese by incorporating them as an 'adjunct culture' alongside the standard cheese starter cultures. This approach allows them to control the strain and concentration for a functional product.