Great coffee makes little popping noises halfway through the coffee roast. Known as the Maillard Reaction, many instant coffee drinkers are unaware of this crucial popping- process that gives their coffee a distinct flavor.
The popping noise occurs as roasted beans reach extreme temperatures. The bean always transitions from a green color to a dark or very dark brown.
Do Roasted Coffee Beans Make Noise?
During the process of roasting coffee beans, the beans make cracking and popping noises.
This process is largely unknown to many coffee drinkers, but to those who roast coffee beans regularly the noise the bean makes is as essential as color and temperature changes during the roast.
The noise roasted coffee makes is an indicator of several underlying processes that the bean is transitioning through. Before coffee is roasted, it is a greeny- leafy color and almost unrecognizable from the coffee we see on supermarket shelves.
The noises occur as the bean undergoes a chemical transition at high temperatures. The beans change color and begin to break down and release their coffee flavor.
This process is accompanied by a popping and cracking noise, that changes as the bean moves from one stage of the process to another.
Why Does Coffee ‘Pop’?
Roasted coffee makes a popping noise due to reactions that occur within the bean once it reaches a certain temperature. The popping noise is a crucial indication that the roasting process is in full swing, and will end in perfectly roasted beans.
Formally known as pyrolysis, the point where the beans begin to crack and pop is what produces the familiar flavor and smell of coffee.
It occurs within 5 minutes of the roasting process, pyrolysis is when the beans begin to release oxygen, and the physical and chemical molecules of the bean begin to break down and separate, resulting in a popping noise.
How Long Does Coffee Bean Popping Last?
Known to coffee connoisseurs as the ‘crack’ roasted coffee beans will continue their cracking and popping process for between 1 and 3 minutes, after which the separation process will have finished and the noise will settle down.
Coffee beans will only begin to crack and pop once the beans reach 380 degrees F. Therefore it could take anywhere between 5 and 15 minutes for the beans to begin cracking and popping.
What Happens Once The Coffee Beans Stop Making Noise?
Known as the ‘first crack’ once the roasted coffee beans have stopped making noise, you should continue to roast them on a lower heat.
The higher heat is required to initiate processes of chemically separating the molecules within the bean to release the texture of the coffee and flavor. After this phase, the higher heat is no longer needed so you should move to the ‘second crack’ and reduce the heat to 426 degrees F.
At 426 degrees F, the coffee will change color once again. The beans will begin to lighten and turn to that wonderful golden brown color that specialty coffee drinkers are familiar with.
What Is the Difference Between the First and Second Crack?
The ‘crack’ formulation is used by experienced coffee roasted as an audible due to increase or decrease heat temperatures when roasting coffee beans.
The first crack is heard at high temperatures and an indication that the coffee bean is releasing oxygen, water vapor, and breaking down some of the core molecules that give coffee is familiar taste and aroma.
The second crack begins within 30 seconds of the end of the first crack. Once the cracking and popping sounds of the first crack stop and the heat is reduced, the second crack will begin.
The second crack is when the bean is releasing carbon dioxide that has built up during the first crack. This cracking sound sounds a little different from the first. It is a little sharper and sounds more like a snap than a crack or a pop.
How Long Should The Second Crack Last?
The second crack starts within 5 – 15 minutes after the first crack. Basically, whatever length of time it takes for the beans to reduce in temperature from the first crack to the second crack – this is dependant on whether you are air roasting your beans or roasting them in a drum.
The longer you leave the second crack the darker the roast will be. Most coffee roasters advise turning the heat off and cooling the roast entirely as soon as the second crack begins.
The second crack will then happen irregularly as the roast begins to cool. The series of snaps will be very fast, like when you pour milk over a bowl of Rice Krispies.
Why Aren’t My Coffee Beans Making Noise?
Some coffee beans may not crack as expected. If you are roasting beans that are porous or have cracks or fractures on their surface, then the oxygen may be released without breaking open the brittle skin of the bean.
Continue the process, and if the coffee comes out just fine then it is still considered a successful roast. However, if the beans are a little off, you can try misting them or increasing the drying phase, if that does not fix the issue then the beans are bad and should be thrown away.
How Can I Reduce the Noise of My Coffee Roaster?
Those who roast coffee regularly know that it can be a pretty loud process, and of course the bigger your roaster and the more beans you have the louder the process is.
Unfortunately, there is no way to reduce the sound of your coffee roaster, other than to reduce the size of the actual roaster itself.
Most independent stores have 5-kilo roasters, that make an acceptable amount of noise as the coffee roasts. This is ideal for independent coffee shops that wish to showcase their cafes.
The problem with larger, 10-kilo roasters is that the noise level is difficult for some to tolerate, so it is not advisable that you have a larger roaster upfront in your cafe.
However, 10-kilo roasters are usually only used by manufacturers of packaged coffee and can be so loud that their employees have to resort to wearing earplugs to protect their hearing.
Hi, I’m Jen Williams, chief editor and writer for ThirstPerk.com.
I’ve been drinking coffee and tea for most of my life, but it wasn’t until I started working at Thirstperk.com that I became an expert on the subject. I’m a total caffeine addict who has spent hours upon hours reading about and experimenting with the different types of coffees out there in my search to find the perfect cup of joe.
I’ve been a tea lover for as long as I can remember as well. I grew up in a house with a mom who loved to drink herbal tea, and I think that’s where my love for tea first began. These days, I’m always on the lookout for new and interesting teas to try, and I love experimenting with different brewing methods and flavoring combinations.
