Tea is one of the most popular beverages in the world, prized for its aroma, flavor, and potential health benefits. However, there is some debate around whether it is safe to leave brewed tea sitting out at room temperature or if it is better to refrigerate it.
Quick Answers
Here are some quick answers to common questions about leaving brewed tea out:
- It is generally safe to leave tea sitting out for a few hours. However, leaving it for longer than that can lead to bacterial growth.
- Green and white teas are more delicate and prone to going bad if left out too long compared to black tea.
- Refrigerating brewed tea is ideal for keeping it fresh and preventing bacterial growth for up to 3-5 days.
- Tea may develop an off taste or smell if left out too long as compounds in the tea oxidize.
- Leaving tea out overnight is not recommended as the temperature is ideal for growing bacteria.
Does Brewed Tea Go Bad?
Like many other beverages, brewed tea does not last forever. Its quality and safety begin to decline once it has been prepared. This is because there are compounds in tea that can oxidize or degrade over time. Exposure to oxygen and warmer temperatures accelerate this process.
Tea can also begin to grow bacteria once brewed, especially if left out at room temperature overnight or longer. Bacteria need moisture, nutrients from the tea compounds, and the right temperature range to grow and multiply.
So while brewed tea does not necessarily “go bad” right away, its quality and safety can deteriorate if it is left sitting out unrefrigerated for too long.
Signs Brewed Tea Has Gone Bad
Here are some signs that indicate your tea has exceeded its shelf life and may have gone bad:
- Change in appearance: The tea looks cloudy, changes color, or has particles floating in it.
- Off odors: It begins to smell sour, moldy, or strange.
- Off flavors: The taste is distinctly off, bitter, sour, or strange.
- Mold growth: You see fuzzy mold growing on the surface of the tea.
- Upset stomach: Drinking the tea makes you feel nauseous or gives you stomach cramps.
If you notice any of these warning signs, it is best to err on the side of caution and discard the tea rather than drinking it.
Does the Type of Tea Matter?
The type of tea leaves used to brew the tea can impact how long it stays fresh and how prone it is to bacteria growth when left out.
Green Tea
Green tea is less oxidized than black tea during processing. This helps retain its delicate flavor and health compounds, but also makes it more vulnerable to degradation.
Many sources advise drinking green tea within 2 hours of brewing for the best flavor and to avoid bacterial growth. The antioxidants and nutrients in green tea also decline rapidly over time.
Black Tea
Black tea is allowed to oxidize more fully during processing. This alters the flavor but also makes it more hardy and stable. Black tea can often last up to 8 hours before losing flavor or becoming unsafe to drink.
White Tea
White tea is the least processed type of tea. It is more delicate than green tea and lacks the hardiness of black tea. Most experts recommend drinking white tea within 4 hours for optimal freshness and safety.
Herbal Tea
Herbal teas are made from dried fruits, herbs, spices, flowers or other plant materials. They do not actually contain leaves from the tea plant (Camellia sinensis). Herbal teas can usually keep for up to 12 hours before losing quality.
Oolong Tea
Oolong tea falls somewhere between green and black tea in terms of oxidation. It also falls between the two with regards to how long it stays fresh. For maximum flavor and safety, oolong tea is best consumed within 4-6 hours.
Does Milk or Sweeteners Impact Freshness?
Adding ingredients like milk, sugar, honey or lemon to your tea can impact how long it stays fresh and safe to drink:
- Milk – Can provide additional nutrients for bacteria to grow, decreasing shelf life to 2-4 hours.
- Sugar – Can also feed bacteria growth, lowering shelf life to 4-6 hours.
- Honey – Has antimicrobial properties so has less impact on shelf life, which remains 4-6 hours.
- Lemon – Is acidic so helps block bacterial growth, shelf life remains 4-8 hours.
To get the maximum shelf life out of brewed tea with additions, refrigerate it and consume within 12-24 hours.
Proper Storage to Maximize Freshness
Here are some tips for storing brewed tea to keep it tasting great and minimize bacterial growth:
Refrigeration
Refrigerating tea after it has been brewed is the best way to maximize shelf life. The cool temperatures slow chemical reactions and bacterial growth. Tea stored in the fridge in an airtight container can last up to 5 days.
Airtight Containers
Storing tea in an airtight container helps block oxygen exposure. Oxygen accelerates oxidation and degradation of flavors. Opt for containers with tight lids.
Opaque Containers
Light exposure can also degrade tea compounds and flavor over time. Use opaque containers like stainless steel thermoses or ceramics to block light.
Consume Sooner
Even with proper storage methods, it is still best to consume tea within a day or two for the freshest taste.
Brewing Tips for Fresh Tea
Certain brewing methods and practices can also help yield fresher tea:
- Use fresh, high-quality tea leaves within their shelf life.
- Use filtered water to avoid compounds that can alter flavor.
- Brew tea at optimal temperatures based on variety.
- Avoid oversteeping tea which can make it taste bitter.
- Store tea leaves in sealed containers in cool, dark places.
- Clean teapots and strainers thoroughly to avoid bacteria buildup.
- Never leave tea leaves sitting out wet for prolonged periods.
Can You Reheat Tea?
It is not recommended to reheat tea more than once. Reheating can increase acidity, give tea a metallic taste, and accelerate oxidation. However, tea can be reheated once while still retaining flavor if done properly:
- Only reheat up to 2 hours after brewing
- Reheat using stove, microwave, or hot water bath
- Avoid boiling or overheating
- Consume reheated tea immediately
- Do not reheat more than once
Is Tea Still Safe if Left Out Overnight?
Leaving brewed tea out at room temperature overnight is generally not recommended. The hours-long period within the “danger zone” temperature range of 40-140°F poses a risk of significant bacterial growth.
Bacteria multiply rapidly between these warmer temperatures. Potential pathogens include Bacillus cereus, Staphylococcus aureus, and Clostridium perfringens. Consuming tea contaminated with these bacteria can cause foodborne illness.
For maximum safety, brewed tea should be refrigerated and consumed within 24 hours. Tea left out overnight should be discarded.
Can You Freeze Brewed Tea?
Freezing brewed tea is a good long-term storage option to maintain freshness. The freezing process stops chemical reactions and bacterial growth that degrade tea over time. Properly frozen tea can retain optimal flavor and health benefits for up to 3 months.
Tips for freezing tea:
- Brew a strong batch of tea to allow for dilution from ice crystals
- Cool tea to room temperature before freezing
- Pour tea into freezer-safe airtight containers
- Leave space at the top for expansion
- Store containers flat in freezer
- Once frozen, keep frozen until ready to thaw and drink
One drawback to freezing is that ice crystals can slightly damage leaf integrity. Tea may need to be strained after thawing. The freezing process can also subtly alter the flavor profile.
How Long Does Tea Last?
How long brewed tea retains optimal taste and safety depends on several factors:
| Tea Type | Refrigerated | Room Temperature |
|---|---|---|
| Green Tea | 3-5 days | 2 hours |
| Black Tea | 5-7 days | 8 hours |
| White Tea | 3-5 days | 4 hours |
| Oolong Tea | 5-7 days | 4-6 hours |
| Herbal Tea | 5-7 days | 12 hours |
As a general rule, tea should not be left out unrefrigerated for more than 8 hours. For maximum shelf life and safety, refrigerate tea and aim to consume it within 3-5 days.
Conclusion
Brewed tea does have a limited shelf life. The tea type, storage method, temperature, and time left sitting out all impact how long it stays fresh and safe to drink. For best results, brew tea properly, refrigerate it in an airtight container, and consume within a day or two. Tea that is left out overnight or longer should be discarded. Following proper brewing and storage guidelines can help maximize the delicious flavor and health benefits of tea.