Were you aware that coffee beans are not technically beans? They are green seeds in their raw state, and when roasted, they change from green to various brown shades and even black. The color of coffee “beans” is determined by the degree of roasting.
Roasting coffee beans extracts the flavor and aroma from the green beans and prepares them for brewing. Unfortunately, green coffee beans lack all of the characteristics of roasted coffee beans – they are spongy and soft, with a grassy aroma, and cannot be brewed in this state.
When beans are roasted at extremely high temperatures, chemical changes occur. When they reach the desired temperature, they are immediately cooled to stop the process. Roasted beans weigh less because the moisture has evaporated, and they smell like coffee.
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What Happens to Coffee Beans After They’re Roasted?
During the roasting process, raw, green coffee beans undergo physical changes. Heat changes the compact, dense beans from a green seed to a flavorful, aromatic bean. Let’s take a look at the changes that occur as a result of the roasting process:
Color
Coffee bans are blue-green before roasting and turn brown due to the development of melanoidins. Melanoidins are polymers that form when amino acids and sugars combine under heat.
A papery outer layer known as chaff or silverskin will also come off during the roasting process. Roasters frequently use the level of color to determine profile and quality.
Dried green process beans contain about 10 to 12 percent water, reduced to about 12 percent after roasting. Additional water is formed due to the chemical reaction, but it is vaporized when the coffee is roasted, causing the coffee to change structurally.
Mass and Moisture
Due to moisture loss and the transformation of dry material into gases, roasting reduces the overall mass of the beans.
Beans typically lose 12 to 20% of their total weight. To determine which batches require additional quality assurance attention, Roasters track percent weight loss.
Volume
Coffee beans have solid cell walls with external rings to increase strength and stiffness. On the other hand, the roasting process raises the temperature and converts water into gas, resulting in high-pressure levels inside the bean.
The cell walls’ anatomy changes from stiff to rubbery due to this pressure. This is because polysaccharides are present.
The internal body pushes outward towards the cells, creating a gassy void in the center—the volume of the beans increases as their mass decreases.
This gas buildup is carbon dioxide, which will be released after roasting. In addition, because of the increased porosity, roasting makes the beans more soluble. This is required for them to be transformed into a delectable cup of java.
Oils
Coffee beans contain oils or lipids that rise to the surface as compounds move from the bean’s center due to the high internal pressure.
The oils aid in the retention of volatile compounds within the cell. These chemicals have a high vapor pressure at room temperature and are necessary for the aroma and flavor of the coffee. These compounds would disperse if the oils were not present.
The longer they roast, the more dramatic the physical transformation. Roasting continuously reduces the density. As time passes, more gases form. Oil will rise to the surface of the bean in dark roasts.
These differences explain why dark-roasted coffee tastes different than lighter-roasted coffee. Significant chemical changes also affect the profile.
What Is the Difference Between Roasted Coffee Beans and Raw Coffee Beans?
Unexpectedly, there is a growing interest in and demand for unroasted coffee beans. First, we will look at some of the health benefits of raw coffee beans:
Caffeine levels are lower in raw coffee beans.
Raw coffee beans are harvested directly from the Arabica plant and are left in their natural state before being packaged and distributed to consumers.
These coffee beans are ideal for people who want to cut back on their caffeine intake. A cup of roasted coffee contains approximately 100mg of caffeine, whereas a cup of unroasted coffee contains only about 20 mg of caffeine. So you won’t be able to sleep if you drink this.
They Are High in Antioxidants
Chlorogenic acid is a necessary component of green coffee beans. This potent antioxidant regulates the body’s lipid and glucose content, providing various health benefits.
It protects cells from free radical damage and lowers your body’s overall oxidative stress levels.
Free radical damage can fatigue you, weaken your immune system, and increase your risk of inflammation. However, the high antioxidant levels in chlorogenic acid found in raw coffee beans help keep these issues at bay.
Raw Coffee Beans Aid in Weight Loss
A recent study found that volunteers who tried green coffee for weight loss had a 10.5 percent decrease in body fat and a 16% decrease in body weight.
This is due primarily to the chlorogenic acid properties, which increase energy levels and aid in burning fat stores in the body. However, it can also reduce cravings and lower your metabolism.
It can even slow down the process of sugar absorption in your bloodstream, allowing you to maintain consistent insulin levels.
It has the potential to improve mood and focus.
Green coffee beans have lower caffeine levels, improving cognitive performance and mood. This is because caffeine and chlorogenic acid inhibit the adenosine neurotransmitter in the brain.
This is a depressant of the central nervous system. But, on the other hand, it boosts your energy levels and dopamine levels.
The increase in dopamine levels helps prevent stress and depression while also increasing motivation.
It aids in the reduction of blood sugar levels.
Because of the chlorogenic acid, green coffee beans help keep your blood sugar and blood pressure in a healthy range.
Chlorogenic acid has hypoglycemic properties, which interact with your body’s lipid metabolism, lowering cholesterol levels.
Because green coffee reduces inflammation, you are less likely to crave sugary foods, which keeps your glucose levels stable. This is critical for maintaining a normal blood sugar level.
Green coffee beans may reduce your chances of developing type 2 diabetes. This is because chlorogenic acid reverses the fat buildup caused by years of poor nutrition by affecting the genes responsible for adipogenesis.
The flavor of Green Coffee Beans
Green coffee beans are popular among doctors due to their numerous health benefits. Green coffee, on the other hand, will not taste like coffee.
Many people describe the taste as grassy and acidic, and they would rather not drink it. However, if you drink green tea, you may be able to tolerate the taste of green coffee.
How Are Coffee Beans Roasted?
Coffee begins as a small red fruit harvested and processed to remove the skin, pulp, and inner skin parchment. When the process is completed, the green inner seed is dried.
We know that roasting removes moisture from the bean, causing it to dry out and expand in volume. Some natural sugars decompose into CO2 gas, while others caramelize into the flavors that give coffee its distinct flavor.
Coffee roasting is done in ten stages. It is up to the roaster to determine which stage is preferred:
1st. GREEN Despite temperature increases, the coffee beans retain their natural green color.
2. THE COLOR YELLOW. The color gradually turns yellowish, and the beans emit a grassy odor.
3rd. STEAM. The water within the bean evaporates, releasing steam.
4. THE FIRST CRACK. (It’s a Cinnamon Roast.) The sugars within the beans begin to caramelize, and a cracking sound can be heard.
5. THE CITY ROAST. After the first crack, the beans have reached a minimum roast level that is suitable for grinding and brewing for most coffee enthusiasts.
CITY PLUS ROAST. The beans expand in size as they caramelize more and migrate. This roasting level is well-liked.
7. CITY ROAST IN ITS ENTIRETY. This is a darker roast in which the beans are nearly cracked for the second time.
8. THE SECOND CRACK (FULL CITY ROAST PLUS). The cracking of the beans becomes more violent, and the roasting releases more intense layers of flavor.
DARK ROAST 9 (FRENCH ROAST). The sugars burn as much as they can without destroying the flavor, and the smoke turns pungent. The structure of the beans will break down, but the flavor will remain.
BURN TEN. The odor will change from intense to rank, and the beans will be burnt.
Last Thoughts
Coffee beans are roasted to release the flavors and aromas that have been locked within the beans. Roasting is a complex process that transforms the beans from the inside, producing toasty beans with a delicious aroma.
Most of us look forward to that aroma in the morning, and it’s all thanks to roasting.
Many people are unaware that green coffee, with its numerous health benefits, is now a thing. It’s worth trying this coffee for its medicinal properties alone, but don’t expect it to taste like your typical morning brew.
Instead, the taste is only described as grassy and acidic. Roasting is a method that deserves to be praised because it adds flavor and a rich aroma to our daily lives.