Tea can be stored below room temperature for better long term storage capabilities. Storing tea correctly is essential if you want to enjoy your tea over extended periods of time.
There are some major benefits to storing appropriate teas in the fridge or the freezer. But there are risks and things to be avoided when dealing with lower temperatures and tea. Especially when the temperature is changed quickly.
SHORT ANSWER – Things To Know About Keeping Tea In The Fridge
Keeping delicate and aromatic teas in the fridge can be beneficial for long term storage. At lower temperatures, green teas and other delicate teas will retain their aroma and freshness for longer. Contamination with foreign smells and water condensation are possible when storing tea in the fridge.
To fully understand the positive effects and possible risks of storing tea in the fridge or the freezer, a more detailed answer is necessary. Further, the types of tea that benefit the most and least from storage under these conditions will be disclosed.
With this post you will be able to decide whether storing your teas in the fridge or freezer is worth it to you. You will know the advantages as well as how you can mitigate the risks and disadvantages. Nobody wants to lose the aroma or foreign smells and mold ruining their teas, right?
The Benefits Of Storing Tea In The Fridge
What most tea vendors and enthusiasts will tell you about storing tea in the fridge is that it will keep the tea fresh for longer and help the tea to retain its aroma. This is very true, but that is not all there is to it.
The lowered temperature will further keep your teas from losing aroma and taste over time through slower oxidation and degradation. Also, storing teas in the fridge will passively help with lowering the exposure to harmful ultraviolet radiation and oxidizing agents.
Retaining The Aroma And Freshness Of The Tea
Preserving the freshness and aroma of delicate teas such as Matcha and other green teas is the primary reason for storing teas in the fridge. But what exactly is preserved inside your teas and what would happen if you weren’t storing it in the fridge?
Knowing the processes behind the loss of aroma and freshness when storing tea for more than a few months is essential to understand the change in taste and gauging whether a tea needs to be stored in the fridge or not.
Why Is The Preservation Of Aroma And Freshness Desirable?
There are many delicate teas where the freshness and aroma is what makes the tea good and enjoyable. Yellow tea, light oolong tea, green tea and especially Japanese green tea such as Matcha and Gyokuro will lose a lot when stored at room temperature and/or in the open air.
Storing such teas in the lower temperature environment of a fridge or freezer will allow the tea to be good 3 months, 6 months or even a year or two from now.
The time it takes for the aroma and freshness to disappear is partially determined by the temperature, but also by the air-tightness of the container you use.
Why Higher Temperatures Cause Tea To Go Stale Quickly
Storing tea at room temperature or higher temperatures will cause the high notes of the tea to vanish quickly. After only a few months, an aromatic and fresh-tasting green tea will taste stale and unexciting.
With increasing temperatures this process gets faster and faster. If you store your teas at room temperature, the rate at which your tea loses its flavor is already high.
Storing your tea close to the kitchen, on the refrigerator or near other heat sources, the tea will become stale much quicker. There is a reason for the recommendation of storing teas in a cool and dark place.
On the other hand, lower temperatures will slow down the loss of flavor, aromatic compounds and the freshness of your teas. Storing your teas in the fridge or freezer can prevent the loss of these compounds and keep your tea good for a long time.
How Lower Temperatures Prevent The Loss Of Aroma
If you have ever used rubbing alcohol, you will be familiar with the concept of evaporation. The most important reason for storing your tea in a cool place is the resulting slowed evaporation rate.
All the chemicals you smell when you hold the dried tea leaves to your nose are volatile compounds. They are responsible for the floral, sweet and aromatic smell as well as the grassy taste common in Japanese green teas.
At a certain temperature, these volatile compounds will be transferred from your tea into the air surrounding it. If there is enough air circulation, the volatile compounds will be carried away and lost.
Lowering the temperature will result in a slower evaporation rate. Less volatile compounds will be found in the air around the tea and more will stay on and inside of the tea leaves.
Below a certain temperature, which varies a lot between different compounds in the tea, there is next to no evaporation. Compounds which would evaporate and be lost at room temperature may stay in the tea indefinitely in the fridge.
What this means for your tea is that when storing teas at lower temperatures or even in the freezer, the tea will not lose as much flavor and aroma. That is the primary reason why most vendors recommend storing delicate green teas in the fridge.
Storing Tea In The Fridge Slows Oxidation And Decay
The primary difference between green tea and black tea is the oxidation level of these teas. Back tea is already fully oxidized and not very vulnerable to further oxidation
Green tea, on the other hand, is very vulnerable to oxidation and should be kept from contact with oxidizing agents as much as possible. The problem here is that the oxygen in the air is an oxidizing agent itself.
How Does Cool Tea Storage Prevent Oxidation?
The oxidation of the tea by the oxygen in the air is slowed a little bit by lowering the temperature. The oxidation is not stopped or slowed sufficiently to prevent oxidation over time, though.
What keeps your tea from getting oxidized in the fridge is more of a passive reason. Most teas that will be stored in the fridge will be stored with an air-tight container around them.
Tins, bags or anything else that is used to store your tea will prevent oxygen from getting to the tea. Once all the oxygen inside the container is spent oxidizing the tea, the oxidation will come to a halt.
Storing teas outside the fridge, tins, and containers that are not air-tight are common. I would recommend using an air-tight storage container for all teas both inside and outside the fridge.
The only tea I would exclude here is Pu Erh tea due to microbial activity inside the leaves depending on the oxygen and regular air-circulation that is not given with an air-tight container.
Lower Temperatures Cause Lower Decomposition Rates
If the preservation of aroma, freshness, and taste is your primary concern, the lower temperatures inside a fridge or freezer have an additional advantage over storage methods at room temperature.
You may remember from your chemistry class that the rate of chemical reaction will increase exponentially with higher temperatures. The reason behind this is simply the increased activity on a molecular scale. What does this mean for tea and tea storage?
With increased temperatures, any reactions that take place inside your tea will be faster and more prominent. With Pu Erh tea and other teas that you want to age, this may be desirable. But it is not with fresh and delicate teas.
The speed of the natural decomposition and decay of compounds found inside your tea will be exponentially slower in the fridge or freezer. Like a lot slower. Your tea may decompose up to 100 times slower in the fridge when compared to room temperature.
Lowered Air-Circulation And Light Exposure In The Fridge
There are more than just one aspect to the benefits of storing teas inside the fridge that are on the more passive side. For one, the tea will be exposed to less (fresh) air. Secondly, the tea will not be exposed to as much ultraviolet radiation inside the fridge.
Both the lower air-circulation and lowered light exposure are effects that are independent of the lowered temperature but are relevant when thinking about storing tea in the fridge or freezer.
How Less Air-Circulation Keeps Your Tea Fresh
Airflow rarely has positive effects on tea storage. About the only teas that would benefit from fresh air are Pu Erh teas and other fermented teas with microbial or enzymatic activity.
The effect of high air-circulation on more delicate teas is largely negative. The loss of aroma and freshness through oxidation or evaporation of compounds responsible for the taste is not desired.
Most green teas, yellow teas and white teas will lose their flavor and smell quickly when left out in the open. A sealed container, be it a small box or a whole refrigerator will help to avoid this.
As mentioned before, the oxidation level largely defines the looks and taste of your teas. Through more airflow, your tea is introduced to more oxygen which will oxidize your tea.
Further, the loss of volatile compounds is much faster when the concentration in the air surrounding your tea is low. This means that the loss of aroma is faster with higher airflow.
Why Protection From Ultraviolet Light Is Important
The reason why you store tea in a dark place is to protect it from ultraviolet light. Ultraviolet light has a lot of energy and is able to destroy chemical compounds in your tea.
The more UV-light your tea is exposed to, the more chemicals will be destroyed. You will notice the difference as some of these chemicals are responsible for the look, smell and taste of your tea.
This is the same reason why various items get discolored over time if they are exposed to direct sunlight. Within a bag, box or refrigerator that blocks ultraviolet light, your tea won’t be destroyed by this.
Lowered Microbial And Enzymatic Activity
The desired aging process that is desired with some teas, requires enzymes and bacteria to slowly grow and change the composition of the tea over time. This is not true for delicate teas.
Delicate and aroma-intensive teas will lose flavor through enzymes, bacteria and fungi. The worst thing that could happen is the growth of bacteria and mold which render your tea undrinkable.
So what good does a refrigerator do? How would a lowered temperature keep your tea from losing flavor to bacteria or enzymes?
Decreased Or Increased Risk For Bacteria And Mold?
The lowered temperature of a refrigerator can help reduce the growth of bacteria and mold. The growth of bacteria is slowed far more than the growth of mold due to changes in humidity.
Bacteria will grow at various rates which partially depend on the surrounding temperature. Often, the ideal temperatures of bacteria are at or above room temperature.
With temperatures far exceeding or much lower than the ideal temperatures, the growth rate will decrease. This is the reason why tea and other foods won’t go bad as quickly in the fridge.
The activity of mold will be slowed by the decreased temperature, too. But the likeliness of mold on your tea may increase due to the formation of water droplets and condensation on your tea.
Temperature And Enzymes
Enzymes are large molecules that are promoting certain reactions in all plants and animals. They make reactions possible that would otherwise not occur under these conditions.
How fast and effective the enzymes work will largely depend on the temperature. Enzymes will always have an ideal temperature at which they will be the most productive.
If the temperature gets lower than this, the enzymatic activity decreases. Depending on the enzyme, the temperatures inside a refrigerator may cause the reactions to come to a complete halt.
At much higher temperatures, the enzymes may get destroyed. Enzymes are quite sensitive to high temperatures, which is the reason for the roasting and steaming of green tea to deactivate the enzymes in the tea.
Disadvantages And Risks Of Storing Tea In The Fridge
The fridge should not simply be considered the perfect storage option. There are a few negatives that can destroy your tea if you do not take caution to prevent this.
Water Condensation And Humidity
The primary problem with refrigerators is the high humidity inside. All refrigerators will have some droplets forming in the back due to condensation of the humidity in the air.
Changes In Relative Humidity Due To Temperature
Relative humidity is the percentage of water contained in the air when compared to the maximum water content in it at a given temperature. If the temperature is decreased, the maximum water content is decreased.
When more water is contained in the air than it can hold, the water will condensate on a surface in its surroundings. If you live in an area with high humidity such as coastal areas often are, you must take care.
Even if you protect your tea from the water droplets already in the fridge, the possibility of water condensation inside the tea container or bag is still there.
With high relative humidity outside the fridge, you will not be able to prevent this. Some teas will be able to absorb this water while others are at higher risk.
Is It Possible To Prevent Condensation?
Preventing condensation and the formation of water droplets is not possible when dealing with temperature changes and high air humidity.
You could increase the temperature inside the fridge to lower the risk or decrease the relative humidity outside the fridge (inside the tea container) before cooling it down.
Naturally, matcha is powdered tea and will be able to absorb large amounts of water before water droplets form on its surface. Whole leaf tea, on the other hand, is more vulnerable to the formation of water droplets.
The only time you will be able to properly prevent (further) condensation is when you move tea out of the refrigerator. If you do this, wait for at least 12 hours before opening the bag after taking it out of the fridge to make sure it has reached room temperature.
Rapid Change Of Temperature
Rapidly changing the temperature of the tea you store will hurt the aroma and flavor of your tea. Slow increases and decreases in temperature are much better than drastic changes.
Storing your tea in the refrigerator will, of course, have you cool the tea leaves rapidly and heating them to room temperature afterward.
These changes in temperature will cause compounds in the tea to crystallize, react or evaporate depending on the temperature, which will change the composition more rapidly than storing the tea at a constant temperature.
Absorption Of Smells And Odors
Every refrigerator is contaminated with smells. A new fridge will tend to smell like plastic or solvent and fridges filled with food will obviously contain the smell of that food.
Why Tea Easily Absorbs Smells And Odors In The Fridge
Tea leaves are dry plant material and very porous and they will easily absorb and volatile compounds, water, smells and odors. If the fridge smells like fish, your tea will too!
Powdered teas such as matcha are more susceptible to external odors. Powdered tea has much more surface area which these smells are able to attach to which will then contaminate the tea with these smells.
A common way to get rid of smells in the fridge is by placing coffee grounds on a plate and placing that inside the fridge for a few days. This will decrease unwanted smells, but if you store tea close to these coffee grounds, the tea will soon smell and taste like coffee.
How To Prevent Smell Contamination When Storing Tea
To prevent tea from taking in any unwanted scents, smells, and odors, a barrier must be created between these two. The easiest would be an air-tight bag which usually will block light and water, too.
Other options are tins, boxes, plastic bags or cellophane. What you use is not as important as making sure that the container is completely sealed, which is nearly impossible to guarantee.
One possibility to completely circumvent this problem is to fully dedicate a refrigerator to tea. Since different types of tea can contaminate each other like black and green tea, you’d need one for each type of tea, though!
Which Teas Should You Store In The Fridge
Now, which are the teas or types of teas that you need to store in the fridge and why? I have added a quick reasoning to each of the teas I have mentioned below.
General Characteristics Of Teas To Be Stored In The Fridge
Generally, teas that have an intense aroma and high notes would benefit from being stored in the fridge. Most green teas, Japanese green teas and delicate oolong teas will be best to be kept from changing.
Of course you would best decide on your own whether you want your tea to change its flavor profile or not. But with teas made for instant consumption, young teas and competition-grade teas, cooled storage options make a lot of sense.
Japanese Green Teas
Matcha is the most obvious and common tea to be stored in the fridge. Due to the high surface area of this powdered tea, this tea will go stale much faster than other teas.
Matcha is a sponge and will absorb smells, scents, odors and water quickly, oxidize more quickly and lose volatile compounds quickly. Do not store matcha for long periods of time.
It is highly recommended to use a small, air-tight and light-blocking container and store it in the fridge. There is a reason why good matcha is sold in small amounts to be consumed quickly, though.
Gyokuro is a very delicate and often very expensive tea that is best consumed in the same year that it was produced. Keeping it fresh until the next year is possible in the fridge.
Every year I get excited about the new teas that we get freshly from the tea fields in Japan. What makes these special is that they are young and fresh and for this reason, they benefit from cooled storage in the refrigerator.
Other Japanese Teas
There are many subtypes of Japanese green teas that all have an intense freshness and grassy taste which would get lost much faster at room temperature.
You’d sure be able to store them at room temperature for a few months, but close to a year the tea may already go stale and taste much less intense.
Chinese Green Teas
Long Jing tea, which is commonly translated to dragonwell tea, is often considered one of the most expensive if not the most expensive teas in China.
This tea is much better when produced recently and quickly loses it’s characteristic fresh and nutty flavor when stored for too long. In a refrigerator, this tea will be good for a bit longer.
Tie Guan Yin
There are different versions of Tie Guan Yin and the one that should be considered for cooled storage is the greener and only lightly roasted variant.
As this oolong tea is very fragrant and aromatic, the loss of volatile compounds can be detrimental to the taste of this tea. For low-cost productions of this type of tea, I would go with regular storage, though.
Other Delicate Green Teas
The other types of tea that have not been listed an discussed here can still be stored in the fridge. This list is a personal preference and only a recommendation.
Many other teas are delicate and rich in high notes and aroma. But these are rarely stored in the fridge as not many consider this to be necessary. You can always compare different storage options through taste.
Which Teas Should Not Be Stored In The Fridge
Some types of tea should never be stored in a refrigerator due to enzymatic and microbial activity being required for long term aging processes. For some other types of tea, the effort of storing them in the fridge doesn’t make sense.
All Types Of Pu Erh Tea
Both raw Pu Erh tea and cooked Pu Erh tea should be stored at or slightly above room temperature to keep the enzymes, fungi, and bacteria inside the tea active.
This type of tea is known for the long-term storage and aging potential and it would be a shame to stop these processes with cooled storage options.
Highly Oxidized And Heavily Roasted Teas
Storing highly oxidized teas such as black tea and darker or heavily roasted oolong teas in the fridge does not give any benefits. Most of these teas do not depend on high notes and aroma.
Over time, many of these teas will be able to develop a more rounded taste although some of the flavors might get lost over time. The risk of mold and smell contamination from a fridge is not worth it for these.
Other Teas That Should Be Stored At Room Temperature
The following types of tea do not benefit from cooled storage and the increased risk of damaging your tea with condensed water, mold or smells is not justified.
Some Yunnanese Green Teas
Some green teas produced in Yunnan, China are close relatives to raw Pu Erh tea and will benefit from storage at room temperature due to enzymatic and microbial activity.
Herbal Teas And Rooibos
Rooibos and herbal teas do not depend on the volatile compounds responsible for the fresh and aromatic taste in tea made from Camellia Sinensis. These teas do not benefit from being stored in the fridge.
There’s a lot more to learn about tea! If you are looking for a good place to start, I highly recommend the book Tea: History, Terroirs, Varieties. You can check its current price on Amazon here.