Scientists tested different protective substances to help a beneficial bacteria called L. reuteri survive the freeze-drying process, which removes water to preserve it for storage. They tested three protective coatings—glutamate, maltodextrin, and trehalose—and heated them at different temperatures to see how long the bacteria stayed alive. Maltodextrin turned out to be the best protector, especially when the bacteria were stored in cool conditions. This research helps companies create better probiotic supplements that maintain their health benefits longer on store shelves.

The Quick Take

  • What they studied: Which protective coating works best to keep beneficial bacteria alive during freeze-drying and storage
  • Who participated: Laboratory study using L. reuteri CRL 1098 bacteria (a strain known for lowering cholesterol and producing vitamin B12)
  • Key finding: Maltodextrin protected the bacteria better than trehalose or glutamate, especially when stored in cool conditions around 30°C (86°F)
  • What it means for you: Probiotic supplements protected with maltodextrin may stay more effective longer on store shelves, though more human studies are needed to confirm real-world benefits

The Research Details

Researchers freeze-dried L. reuteri bacteria using three different protective substances. They then heated samples to high temperatures (50°C, 60°C, and 70°C) to speed up the aging process and see how quickly the bacteria died. This accelerated testing helps predict how long the bacteria will survive during normal storage at room temperature. The scientists used computer models and mathematical equations to analyze the data and predict shelf life—how long the product stays effective before needing to be replaced.

Testing at high temperatures is much faster than waiting months or years to see what happens at normal storage temperatures. This method lets researchers quickly compare which protective coatings work best. Understanding how to keep probiotic bacteria alive during storage is crucial because dead bacteria can’t provide health benefits.

This is a laboratory study that tests the science behind preserving bacteria, not a human trial. The researchers used established mathematical models and computer analysis to interpret their results, which adds credibility. However, the study doesn’t include human participants, so we can’t yet confirm these findings translate to real health benefits for people taking the supplements.

What the Results Show

All three protective coatings helped the bacteria survive freeze-drying, but they performed differently. Maltodextrin emerged as the best protector overall, keeping more bacteria alive during storage at 30°C. Trehalose created a smaller group of extra-tough bacteria that resisted heat well, but this didn’t translate to better overall survival during regular storage. Glutamate fell between the two in effectiveness. The bacteria showed two different survival patterns: a more sensitive group that died quickly, and a hardier group that survived longer.

The researchers discovered that the bacteria’s resistance to heat (measured by something called z-values) varied depending on which protective coating was used. Trehalose produced bacteria with higher heat resistance but lower overall survival rates during storage. The mathematical models used to predict shelf life worked well for describing how the bacteria died at different temperatures, suggesting these predictions are reliable.

This research builds on existing knowledge about freeze-drying probiotics by specifically testing L. reuteri CRL 1098, a strain with potential health benefits. The study uses modern predictive modeling techniques that are more advanced than older methods, allowing for more accurate shelf-life predictions.

This is a laboratory study only—no human participants were involved, so we don’t know if these findings matter for actual health outcomes. The study doesn’t test how the bacteria perform in real probiotic products with other ingredients. The sample size and specific bacterial counts aren’t clearly reported. Results may not apply to other probiotic strains or different storage conditions.

The Bottom Line

If you take probiotic supplements containing L. reuteri, look for products that mention maltodextrin as a protective ingredient and store them in cool conditions (around 30°C/86°F or cooler). Check expiration dates carefully. Confidence level: Moderate—this is solid laboratory research, but human studies are needed to confirm health benefits.

People interested in probiotic supplements, manufacturers of probiotic products, and anyone concerned about whether their supplements are still effective. This is less relevant for people who don’t take probiotics or those with specific medical conditions—consult your doctor first.

The protective benefits of maltodextrin should work immediately upon consumption, but you’d need to take the supplement regularly for several weeks to potentially notice any health effects like cholesterol changes. Shelf life improvements mean the product stays potent longer before you even open it.

Want to Apply This Research?

  • Track probiotic supplement intake by brand and storage location, noting the purchase date and expiration date to monitor product freshness
  • Set a reminder to store probiotic supplements in a cool place (refrigerator or cool pantry) and check expiration dates monthly to ensure effectiveness
  • Log daily probiotic intake and any digestive changes weekly; track storage temperature if possible to correlate with perceived benefits over 4-8 weeks

This research is a laboratory study and does not involve human participants. It describes how to preserve probiotic bacteria in the lab, not proven health effects in people. Before starting any probiotic supplement, especially if you have health conditions or take medications, consult with your healthcare provider. This information is for educational purposes and should not replace professional medical advice. The findings about protective coatings are preliminary and require human studies to confirm any health benefits.