Differences Between Light, Medium, and Dark Coffee Roast Stages - Coffee Bean Roast Degree and Acidity

The roast level of coffee largely determines the flavor direction. When purchasing single-origin coffee beans, you may notice that the labels indicate different roast levels, such as light roast, medium roast, or dark roast. Some also indicate cinnamon roast, city roast, French roast, etc., which often confuses many beginners. In this article, FrontStreet Coffee will guide you through how to distinguish coffee bean roast levels.

Originally, Was There No Standard for Coffee Roasting?

Coffee is grown in producer countries between the Tropics of Cancer and Capricorn, while coffee roasting typically involves transporting green beans to consumer locations for roasting. What is considered light, medium, or dark roast varies by country and region, lacking comparability. Everyone didn't recognize each other's definitions of roast levels. As one of the authoritative representatives in the coffee world, the Specialty Coffee Association of America (SCAA) collaborated with Agtron Company to establish Agtron values as the standard, enabling everyone to communicate on the "same channel" regarding roasting experiences.

SCAA Roast Standards

The SCAA uses infrared caramelization measurement technology (Agtron) to measure the color of coffee beans to determine the roast level, dividing colors from light to dark into eight equal parts to create eight standard color blocks for the coffee industry to use as roast recognition. FrontStreet Coffee currently roasts coffee beans between cinnamon roast and medium roast. FrontStreet Coffee's light-medium roast coffee beans continue caramelization for about 1-3 minutes after the first crack based on the bean characteristics, enhancing the overall complexity of the coffee beans. While caramelizing, acidity decreases and body increases. FrontStreet Coffee's medium-dark roast is actually medium roast, removed from the roaster when approaching the second crack.

Agtron Value #95: Light Roast
Drop time: When first crack密集即将结束

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

Agtron Value #75: Medium Roast
Drop time: After 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: Start of second crack

Agtron Value #45: Full City Roast
Drop time: Before second crack密集

Agtron Value #35: French Roast
Drop time: During second crack密集

Agtron Value #25: Italian Roast
Drop time: When oil begins to surface on the beans

Flavor Performance of Different Roast Levels

The descriptions above may be difficult for beginners to understand. FrontStreet Coffee here divides the 8 roast levels into 4 categories, making it clear for everyone to understand the flavor direction of coffee brewed from beans at different roast levels.

Light Roast (including light roast and cinnamon roast): Light roast coffee beans, when brewed, highlight fruity and floral aromas, with noticeable acidity and a clean, bright taste.

Medium Roast (including medium roast and high roast): Medium roast coffee beans, when brewed, have noticeable body, reduced acidity, and a full, substantial taste.

Medium-Dark Roast (including city roast and full city roast): Medium-dark roast coffee beans, when brewed, have no acidity, with a rich body and a taste that moves from bitter to sweet.

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

So how does FrontStreet Coffee roast the Yirgacheffe Gedeb Dinding Cooperative coffee beans at cinnamon roast level and the Indonesian PWN Gold Mandheling coffee beans at medium roast?

FrontStreet Coffee — Yirgacheffe Gedeb Dinding 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 Dinding coffee bean, FrontStreet Coffee's barista uses low heat to extend the dehydration time of the beans.

Heat to 175°C to enter the drum, damper set to 3, heat at 120; return to 1'32", when drum temperature reaches 140°C, heat unchanged, damper opened to 4; at this point, bean surface turns yellow, grassy smell completely disappears, entering dehydration stage. At 166°C, heat reduced to 100, at 176°C, heat reduced to 80, damper unchanged. At 8'28", bean surface shows ugly wrinkles and black spots, toast smell clearly turns to coffee aroma, 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 too small to stop cracking sounds), develop for 1'30" after first crack, drop at 193.5°C.

How Does FrontStreet Coffee Brew Yirgacheffe Gedeb Dinding Cooperative Coffee Beans?

To better express the rich floral and fruity aromas and 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 toward the center point of the dripper, creating pressure on the coffee grounds through the gravity of water flow to form higher complexity.

Water Temperature: 91-92°C
Coffee Dose: 15g
Coffee-to-Water Ratio: 1:15
Grind Size: 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. Second stage: pour 125g of water in small circles from the center. Pour height 4cm, gentle force to minimize coffee bed disturbance, water flow rate at 4g per second. When 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 extraction is complete, gently swirl to allow the coffee liquid to fully mix before tasting.

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

FrontStreet Coffee — PWN Gold Mandheling Coffee Beans

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

PWN Gold Mandheling coffee beans use natural processing, with moisture content between 12%-15%. These are 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 close the damper immediately after adding beans, steam for 30 seconds then open to 3, until the green beans turn light green or white, open damper to 4, open to 5 (maximum) after first crack.

Heat to 200°C to enter the drum, damper set 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'', bean surface shows ugly wrinkles and black spots, toast smell clearly turns to coffee aroma, 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, adjust heat down to 60°C, damper fully open (adjust heat very carefully, not too small to stop cracking sounds), drop at 204.5°C.

How Does FrontStreet Coffee Brew Indonesian PWN Gold Mandheling Coffee Beans?

To highlight the rich, clean, and aromatic characteristics of PWN Gold Mandheling, FrontStreet Coffee uses a 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, with high fit with filter paper, the flow rate is slower than V60, suitable for brewing coffee that wants to express body.

Water Temperature: 86-88°C
Coffee Dose: 15g
Coffee-to-Water Ratio: 1:15
Grind Size: 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 pour 30g of 89°C hot water for bloom, bloom time is 30 seconds. After bloom, pour the second stage to total 125g, using gentle circular pouring to avoid coffee bed collapse. After pouring, let the water filter and extract slowly. When liquid level drops to one-third, pour the final stage to total 225g, finishing pouring around 1 minute 32 seconds, and ending extraction by removing the dripper around 2 minutes.

PWN Gold Mandheling Brewing Flavor: Sweet medicinal herbs, cinnamon-like spices, citrus peel aromas, rich and intense sweetness, cream walnut chocolate. Fruity acidity is reserved and gentle, aroma carries strong melon fragrance, as temperature decreases medicinal herb aroma emerges, with light spices, medicinal herb notes are rich with intense sweetness.

For more specialty coffee beans, please add FrontStreet Coffee on private WeChat, WeChat ID: kaixinguoguo0925

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473