Should You Refrigerate Kombucha After Opening?

January 2, 2026 •

3 min read

According to brewing experts, raw, unpasteurized kombucha contains live, active cultures of bacteria and yeast, which is why you must refrigerate kombucha after opening. This crucial step halts the fermentation process, preserving the drink's intended taste, fizziness, and beneficial properties.

Quick Summary

Refrigerating kombucha after opening is essential to slow fermentation, maintain flavor, preserve live probiotics, and prevent excess carbonation that can cause spills or explosions. Store it promptly in the fridge and reseal tightly.

Key Points

Required for Raw Kombucha: All raw, unpasteurized kombucha, whether opened or not, must be kept refrigerated to maintain its quality and prevent continued fermentation.
Halts Fermentation: The cold temperature of refrigeration puts the live yeast and bacteria cultures into a dormant state, preserving the intended flavor and carbonation.
Prevents Explosions: Without refrigeration, the ongoing fermentation produces excess CO2, which builds pressure and can cause a messy or dangerous bottle burst.
Preserves Probiotics: The beneficial bacteria thrive in a cool environment, and refrigeration prevents them from dying off, thus preserving the health benefits.
Maintains Taste: Unrefrigerated kombucha quickly becomes more sour and vinegary, losing its balanced flavor profile.
Pasteurized Kombucha: Even shelf-stable, pasteurized kombucha should be refrigerated after opening to maintain its fizz and prevent contamination.

Why Refrigeration is Essential for Opened Kombucha

Opened kombucha must be refrigerated to halt its active fermentation. Kombucha is a living product, created by a Symbiotic Culture Of Bacteria and Yeast (SCOBY). This process, even in a sealed bottle, continues at warmer temperatures. Once the bottle is opened, exposing it to air and higher temperatures, the yeast and bacteria become highly active again.

The cold temperatures inside a refrigerator, typically between 34°F and 40°F (1-4°C), cause these microorganisms to go dormant, drastically slowing fermentation. Without this crucial step, several undesirable changes occur that affect taste, texture, and safety.

Consequences of Not Refrigerating Opened Kombucha

Flavor changes: The continued fermentation will cause the kombucha to become progressively more tart, sour, and vinegary. The delicate balance of sweet and tangy flavors will be lost.
Excessive carbonation: The yeast and bacteria produce carbon dioxide (CO2) as they ferment. In a sealed bottle, this gas pressurizes the container, which can lead to an explosive and messy opening, especially if left at room temperature for an extended period.
Loss of probiotic benefits: While some probiotics can survive at room temperature for a short time, higher temperatures can kill the beneficial cultures. This diminishes the gut-health benefits that are a primary reason many people drink kombucha.
Potential contamination: The seal of an opened bottle has been broken, and if you drink directly from it, you introduce foreign bacteria from your mouth. Refrigeration helps protect the liquid from this contamination, whereas room temperature storage increases the risk of unwanted microbial growth.

The Difference Between Raw and Pasteurized Kombucha

Not all kombucha is created equal, and the type you buy significantly affects its storage requirements after opening. It's crucial to check the label.

Raw (Unpasteurized) Kombucha

This is the most common type found in refrigerated sections of grocery stores. Raw kombucha contains live, active cultures and must be kept cold throughout its life to prevent over-fermentation. Once opened, it should be resealed and immediately returned to the fridge. Leaving it out, even for a day or two, will accelerate flavor changes and carbonation.

Pasteurized (Shelf-Stable) Kombucha

Some brands create kombucha that is heat-treated to kill off the live cultures. This stops the fermentation process entirely, making the product shelf-stable and able to be stored at room temperature before opening. However, even these products need to be refrigerated once opened to maintain flavor and prevent spoilage from external contaminants.

Proper Storage Guidelines for Opened Kombucha

To get the most out of your opened kombucha, follow these best practices:

Refrigerate Immediately: As soon as you open the bottle, return any unused portion to the refrigerator. This is the single most important step.
Seal Tightly: Use the original cap to create an airtight seal. This prevents excess air exposure and helps maintain carbonation.
Store Upright: Keeping the bottle upright helps prevent leakage and maintains a more stable internal pressure.
Consume Within a Week: While refrigerated kombucha is safe for months, its flavor and carbonation will change over time. For the best taste and fizz, aim to drink it within 7-10 days of opening.

Comparison Table: Refrigerated vs. Unrefrigerated Opened Kombucha


Feature	Refrigerated Opened Kombucha	Unrefrigerated Opened Kombucha
Fermentation Rate	Significantly slowed; cultures become dormant.	Accelerated rapidly at room temperature.
Taste Profile	Preserved balance of sweet and tangy flavors.	Becomes more sour, tangy, and vinegary over time.
Carbonation	Maintains moderate fizziness for weeks.	Increases rapidly, potentially causing an explosive opening.
Probiotic Content	Preserved due to the cool, stable temperature.	Diminishes over time as microbes die off in warmer conditions.
Safety Risk	Low risk of spoilage or container pressure buildup.	Higher risk of over-pressurization and contamination.
Shelf Life	Best consumed within 7-10 days for optimal flavor, safe for months.	Palatability decreases significantly within a few days.

Conclusion

Yes, you absolutely should refrigerate kombucha after opening. For both raw and pasteurized varieties, refrigeration is the key to maintaining the intended flavor, optimal carbonation, and beneficial probiotic content. The cold temperature puts the living cultures into a state of dormancy, which slows fermentation to a near halt. Failing to do so can lead to a sour, over-carbonated beverage that might be unpalatable and risk a messy explosion upon opening. By storing your opened kombucha properly in the fridge, you ensure a safe, delicious, and fizzy experience with every pour.

For more detailed information on kombucha, brewing, and storage, you can visit fermentation-focused sites like Fermentaholics.

Frequently Asked Questions

If you forget to refrigerate raw kombucha for a day or two, it will likely be fine to drink, though it may become slightly more carbonated and a little tangier in flavor. Longer than 48 hours is not recommended by some brewers due to potential over-carbonation and flavor changes.

No, refrigeration does not kill the probiotics in kombucha. The cold temperature only makes the yeast and bacteria dormant, significantly slowing down their activity without destroying them.

Unrefrigerated kombucha isn't necessarily unsafe, as the low pH generally inhibits harmful bacteria. However, it will likely become very sour and potentially over-carbonated, and can be at higher risk for contamination once opened.

For optimal taste, opened kombucha should always be stored in the refrigerator. Leaving it at room temperature, even for a short time, will continue the fermentation process and alter its flavor and carbonation.

For the best flavor and fizz, opened kombucha is best consumed within 7 to 10 days. While it can remain safe for longer, its taste and carbonation will gradually diminish.

Signs of kombucha going bad include a swollen or leaking container, a strong off-putting or foul smell (beyond a normal vinegary scent), or visible mold. A new, harmless SCOBY 'mother' or cloudy sediment is normal.

Yes, even pasteurized kombucha that was shelf-stable before opening must be refrigerated once the seal is broken to maintain its quality and protect it from external bacteria.