A Detailed Guide to the Complete Coffee Roasting Process: When Does the Second Crack Occur?

The degree of coffee roasting largely determines the flavor direction of coffee. When purchasing single-origin coffee beans, you may notice that the labels indicate the degree of roasting, such as light roast, medium roast, or dark roast. Some are also marked with cinnamon roast, city roast, French roast, etc., which can leave many beginners quite confused. In this article, FrontStreet Coffee will help you understand how to distinguish the degree of coffee bean roasting.

Was there no standard for coffee roasting initially?

Coffee is grown in producer countries between the Tropic of Cancer and Tropic of Capricorn, while coffee roasting typically involves shipping green beans to consumer regions for roasting. Each country and region has different definitions of light, medium, and dark roasts, lacking comparability. Everyone doesn't recognize each other's definitions of roast degrees. As one of the authoritative representatives in the coffee world, the Specialty Coffee Association of America (SCAA) collaborated with Agtron company to use Agtron values as a standard, enabling everyone to communicate their roasting experiences "on the same channel."

SCAA Roasting Standard

SCAA uses infrared caramelization detector technology (Agtron) to measure the color of coffee beans to determine the degree of coffee roasting, and divides the colors from light to dark into eight equal parts, creating eight standard color blocks for the coffee industry to recognize as roasting standards. FrontStreet Coffee currently roasts coffee beans basically between cinnamon roast and medium roast. FrontStreet Coffee's medium-light roasted coffee beans continue caramelizing for about 1-3 minutes after the first crack according to the characteristics of the coffee beans, enhancing the overall layering of the coffee beans. While caramelizing, acidity decreases and body increases. FrontStreet Coffee's medium-dark roast is actually medium roast, which is removed from the roaster when approaching the second crack.

Agtron value #95: Light Roast
Drop time: As the first crack becomes dense and is about to end

Agtron value #85: Cinnamon Roast
Drop time: Around the end of the first crack

Agtron value #75: Medium Roast
Drop time: After the first crack ends

Agtron value #65: High Roast
Drop time: The quiet period between first and second crack

Agtron value #55: City Roast
Drop time: At the beginning of second crack

Agtron value #45: Full City Roast
Drop time: Before the second crack becomes dense

Agtron value #35: French Roast
Drop time: When the second crack is dense

Agtron value #25: Italian Roast
Drop time: When oil begins to seep to the bean surface

Flavor Performance of Different Roast Degrees

The descriptions above may be difficult for beginners to understand. FrontStreet Coffee divides these 8 roast degrees into 4 categories here, allowing everyone to clearly understand the flavor direction of coffee beans brewed at different degrees.

Light Roast (including Light Roast, Cinnamon Roast): Light roasted coffee beans, when brewed, highlight fruit and floral aromas, with pronounced acidity and a clean, bright mouthfeel.

Medium Roast (including Medium Roast, High Roast): Medium roasted coffee beans, when brewed, have significant body, reduced acidity, and a full, solid mouthfeel.

Medium-Dark Roast (including City Roast, Full City Roast): Medium-dark roasted coffee beans, when brewed, have no acidity at all, with a rich coffee body and a mouthfeel that's sweet after bitterness.

Dark Roast (including French Roast, Italian Roast): Dark roasted coffee beans, when brewed, are very rich, with no acidity, a heavy and solid mouthfeel, and abundant oils.

How does FrontStreet Coffee roast cinnamon-roasted Yirgacheffe Gedeb Cooperative coffee beans and medium-roasted Indonesian PWN Golden Mandheling coffee beans?

FrontStreet Coffee — Yirgacheffe Gedeb Cooperative Coffee Beans

Region: Yirgacheffe Gedeo Zone
Altitude: 1900-2300m
Variety: Heirloom
Processing: Washed
Grade: G1

For beans like Yirgacheffe, FrontStreet Coffee's baristas often use light roasting to present their floral and fruity characteristics. For this washed Gedeb coffee bean, FrontStreet Coffee's barista uses a small flame to extend the dehydration time of the beans.

Set the drum temperature to 175°C, open the damper to 3, heat to 120; return to temperature point at 1'32", when drum temperature reaches 140°C, keep heat unchanged, open damper to 4; at this time, the bean surface turns yellow, grassy smell completely disappears, entering dehydration stage. At 166°C, reduce heat to 100, at 176°C reduce heat to 80, keep damper unchanged. At 8'28", ugly wrinkles and black spots appear on the bean surface, toast smell clearly turns to coffee aroma, which can be defined as the prelude to first crack. At this time, listen carefully for the sound of first crack. At 9'38" first crack begins, adjust damper to 5 (adjust heat very carefully, not so small that there's no cracking sound), develop for 1'30" after first crack, drop at 193.5°C.

How does FrontStreet Coffee brew Yirgacheffe Gedeb Cooperative coffee beans?

To better express the rich floral and fruity aromas and layered complexity of this coffee bean, FrontStreet Coffee decided to use a V60 dripper for brewing. The spiral rib design of the V60 dripper not only extends the contact time between coffee grounds and water but also allows water flow to follow the spiral grooves to the center point of the dripper, generating pressure on the coffee grounds through the gravity of water flow descent, creating higher complexity.

Water Temperature: 91-92°C
Dose: 15g
Ratio: 1:15
Grind: Medium-fine (80% pass-through rate on #20 sieve)

This time using segmented brewing, first pour 30g of water for 30s bloom, at this time the coffee expands into a "hamburger" shape. The second segment, pour 125g of water in small circles from the center. Pour height 4cm, gentle force to minimize disturbance of the coffee bed, water flow rate at 4g per second. When the water level drops to 1/2 of the coffee bed, start the third pour. This pour is also gentle, circling from center outward until reaching 225g total. End extraction when all coffee liquid has dripped through the filter, time is 2'01". After coffee extraction is complete, gently shake to fully mix the coffee liquid before tasting.

Yirgacheffe Gedeb Cooperative Coffee Bean Brewing Flavor: Entry shows citrus, black tea, with cream, caramel, and almond notes as temperature changes, with obvious sweet aftertaste and a clean, sweet mouthfeel.

FrontStreet Coffee — PWN Golden Mandheling Coffee Beans

Region: Sumatra, Aceh, Gayo Mountain
Altitude: 1100-1600m
Variety: Ateng
Processing: Wet-hulled

PWN Golden Mandheling coffee beans use natural processing, with moisture content between 12%-15%. They belong to green beans with relatively high moisture content, with higher deviation values in moisture compared to natural processed beans, so special attention must be paid during dehydration. For green beans with high moisture content, you can try closing the damper immediately after adding the beans, steaming for 30 seconds before opening to 3, until the green beans turn light green or white, then open damper to 4, and open to 5 (maximum) after first crack.

Set drum temperature to 200°C, open damper to 3, after 1 minute adjust heat to 160°C, damper unchanged. Roast to 5'40'', temperature 148°C, bean surface turns yellow, grassy smell completely disappears, dehydration complete, adjust heat to 140°C, damper to 4; at 9'40'', ugly wrinkles and black spots appear on bean surface, toast smell clearly turns to coffee aroma, which can be defined as the prelude to first crack. At this time, listen carefully for the sound of first crack. At 9'54'' first crack begins, reduce heat to 60°C, open damper fully (adjust heat very carefully, not so small that there's no cracking sound), drop at 204.5°C.

How does FrontStreet Coffee brew Indonesian PWN Golden Mandheling coffee beans?

To highlight the rich, clean, and aromatic characteristics of PWN Golden Mandheling, FrontStreet Coffee uses the KONO Meimon dripper for brewing. The "rib" channels of the KONO Meimon dripper extend to the bottom of the hole where coffee liquid flows out. Because the ribs are at the bottom and short, and fit tightly with the filter paper, the flow rate is slower than V60, suitable for brewing coffees that want to express body.

Water Temperature: 86-88°C
Dose: 15g
Ratio: 1:15
Grind: Medium-coarse (65% pass-through rate on #20 sieve)

After wetting the filter paper, pour in the ground coffee, gently level the coffee bed, coffee dose is 15 grams. First segment, pour 30g of 89°C hot water for bloom, bloom time is 30 seconds. After bloom, pour second segment, total water to 125g, using gentle circular pouring to avoid collapsing the coffee bed. After pouring, let water filter slowly for extraction. When liquid level drops to one-third, pour the final segment, total water to 225g, completed in about 1 minute 32 seconds, while extraction ends in about 2 minutes, remove the dripper.

PWN Golden Mandheling Brewing Flavor: Sweet herbs, cinnamon-like spices, citrus peel notes, rich and thick sweetness, cream walnut chocolate. Fruity acidity is restrained and gentle, aroma carries strong melon fragrance, as temperature decreases, herbal notes emerge, with light spices, herbal aroma is rich with intense sweetness.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473