Do frozen coffee beans need to be thawed? Is freezing coffee beans really effective? How long should frozen coffee beans be thawed? Does freezing affect the flavor of coffee beans? Can pour-over coffee beans be frozen for storage?

Freezing is a very popular method for "preserving" coffee beans in recent years. Simply seal the coffee beans and place them in the freezer, and the flavor loss rate will slow down, thereby extending the optimal tasting period. Many friends use this method to stock up on large quantities of coffee beans purchased during FrontStreet Coffee's discount promotions.

However, recently a friend reported that he also used freezing to store coffee beans. But he found that the coffee brewed from these beans after freezing wasn't as aromatic as when stored conventionally, and the flavor wasn't as full-bodied. Therefore, he suspected that freezing wasn't effective and couldn't extend the optimal tasting period.

Although FrontStreet Coffee rarely mentions the topic of freezing coffee beans, it's undeniable that freezing does have some "preservation" effects. Because low-temperature environments reduce molecular thermal motion, the degassing rate of coffee beans slows down (only slows down). The specific degree of slowing mainly depends on the freezer temperature - the lower the temperature, the slower the degassing rate, and the longer the coffee's optimal tasting period. So, the question arises: why did the coffee beans frozen by the friend mentioned above produce less aroma and flavor when brewed compared to conventional storage?

Actually, there are only two reasons: improper frozen storage and incorrect "brewing methods."

What is Proper Frozen Storage?

Some friends might directly put coffee beans in the freezer after receiving them without taking any measures. But actually, coffee beans, like many frozen foods, need to be sealed properly when frozen. The purpose of this is not only to prevent moisture absorption that accelerates aroma dissipation but also to stop coffee beans from absorbing odors from the refrigerator and being contaminated by foreign smells. (For bags with degassing valves, you need to cover the valve with tape.)

But sealing alone isn't enough! When conditions allow, it's best to portion coffee beans when freezing them. The specific method is to divide a bag of coffee beans into several sealed portions, with each portion being just enough for one brew. The reason for doing this is to reduce the impact on other coffee beans each time we take some out. What does this mean? If we freeze an entire bag of coffee beans directly, then each time we take out coffee beans for brewing, the remaining beans in the bag will also be exposed to room temperature.

Although this time is very short, it's enough for condensation to form on the coffee beans, causing them to absorb moisture and affecting their flavor and condition. Therefore, if conditions allow, it's best to portion coffee beans when sealing them for freezing. Of course, more diligent friends can also add another sealed bag outside the packaging bag, which can further slow down aroma loss. Alternatively, you can replace plastic sealed bags with sealed jars, which are more convenient than bags and can be reused~

Why Adjust Parameters When Brewing Frozen Coffee Beans?

Because coffee beans have been in a frozen environment for a long time, their various states and structures will change. For example, the temperature becomes lower, the brittleness becomes higher... these are changes that directly affect brewing. And if we brew such frozen coffee beans without making any adjustments, the final result will likely be similar to this friend's experience - getting a coffee with less rich aroma and less full flavor. How big is the specific difference? FrontStreet Coffee has already prepared frozen coffee beans in the refrigerator for brewing comparison - it's FrontStreet Coffee's Yirgacheffe Gedeb from the bean list used in yesterday's article.

In yesterday's article, FrontStreet Coffee used conventional parameters to brew Gedeb in its normal state, ultimately achieving an extraction rate of 19.46%, with very rich flavor performance: white floral notes, lemon, berry, oolong tea, balanced flavor, round mouthfeel, and long aftertaste. However, when FrontStreet Coffee used the same brewing parameters to brew frozen Gedeb, the extraction rate was 18.06%. The flavor performance was similar but much weaker, and the mouthfeel wasn't as full-bodied, tasting somewhat thin. As you can see, the difference is quite significant. Although not undrinkable, it wasn't as enjoyable. Therefore, if we want to brew delicious coffee using frozen coffee beans, we can choose the following two methods:

1. Increase Extraction Efficiency During Brewing

The first method is relatively simple - just increase the extraction efficiency during brewing. Many friends fail to brew frozen coffee beans well because they don't thaw them after taking them out of the refrigerator and brew them directly. FrontStreet Coffee isn't saying this practice is bad - brewing frozen coffee beans without thawing actually has more advantages. For example, the coffee particles will grind more evenly because the beans are more brittle;同时, because the coffee beans' temperature is lower, less aroma will be lost during grinding, and there's no need to worry about moisture absorption, etc.

However! If we want to brew frozen, unthawed coffee beans, we need to increase the extraction efficiency during brewing. Because coffee beans at low temperatures will absorb a lot of heat from the hot water during the brewing process, leading to decreased extraction efficiency and less aromatic coffee. Therefore, appropriately increasing the parameter's extraction efficiency can solve this problem well. There are many parameters that can be increased, such as increasing brewing water temperature, extending bloom/extraction time, grinding finer, etc.~

2. Thaw Before Brewing

If we don't want to modify the parameters, we can choose to thaw the coffee beans. This method is relatively simpler in comparison. Because when the coffee beans return to normal temperature, we no longer need to adjust the parameters. FrontStreet Coffee probably doesn't need to explain much about the thawing method~ Just take the coffee beans out of the refrigerator and let them sit for more than half an hour. However, it's important to note that we shouldn't open the package during thawing, keeping the coffee beans in the sealed environment of the bag.

Because once we open the package, condensation will immediately form on the surface of the coffee beans due to the huge temperature difference. This will cause the coffee beans to absorb moisture and soften, affecting coffee extraction, flavor, and other aspects. So everyone needs to pay attention to this point~ So the above are some precautions we need to take when freezing coffee beans and brewing frozen coffee beans. Although FrontStreet Coffee has said so much, we don't recommend that beginners or friends who are not yet familiar with brewing use freezing to store coffee beans. Because freezing has a significant impact on brewing, and using freezing for "preservation" before becoming familiar with the process might backfire, making it impossible to brew the delicious flavors of the coffee beans. So, everyone should decide for themselves~

Important Notice :

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FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473