How does temperature change coffee extraction?

Cold drip coffee is low-temperature slow extraction, while iced pour-over is high-temperature fast extraction, and the two paths produce different flavors and mouthfeel. Temperature controls how quickly oils, acids, and sugars break down in the grounds, so the same beans can taste quite different depending on the method used.

High-temperature brewing releases sourness, sweetness, and bitterness quickly, but pushed too far it pulls woody fiber notes. Low-temperature brewing works slowly, holding aroma and cutting harsh edges. A Honduras Moca Estate Sherry sample shows the ratios, fermentation points, and storage advice for both, plus a simple iced Americano method.

What exactly is the difference between cold drip coffee and iced pour-over coffee? Front Street receives this question almost every day. In summary, cold drip is low-temperature slow extraction, while pour-over is high-temperature fast extraction, and the flavors and mouthfeel produced by these two paths each have their own characteristics. From Front Street's perspective, this article first sorts out the impact of temperature on coffee extraction, then explains the advantages and shortcomings of high-temperature and low-temperature extraction respectively, and then uses Honduras Moca Estate Sherry coffee beans as a sample to fully demonstrate the production process, coffee-to-water ratio, fermentation points, and storage suggestions for cold drip coffee and iced pour-over coffee, and also includes a simple method for iced Americano, to help coffee lovers understand the flavor directions of different iced coffees.

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What is the difference between cold drip coffee and iced pour-over coffee? Front Street is asked this question almost every day. Simply put, cold drip coffee is low-temperature slow extraction, while pour-over coffee is high-temperature fast extraction. The coffee flavor and mouthfeel handled by these two extraction methods will differ. In this article, Front Street will explain what cold drip coffee is and what iced pour-over coffee is.

What impact does temperature have on coffee extraction? Temperature affects the breakdown rate of oils, acids, and sugars in coffee. Depending on how quickly this process occurs, the aroma, taste, and texture of the coffee vary greatly. This is also why different extraction methods can produce coffees of different qualities.

Characteristics of high-temperature coffee extraction

The advantage of high-temperature extraction is that it can quickly extract the flavor substances in coffee, causing the tannic acid in the coffee to quickly decompose into pyrogallic acid, producing sourness, sweetness, and bitterness, which is what Front Street often calls the process of releasing coffee flavor. The disadvantage of high-temperature extraction is that it easily causes the coffee flavor to be fully released, and then it begins to release the taste of the coffee bean's woody fiber, which is what we often call off-flavors, woody notes, and other unpleasant tastes.

Characteristics of low-temperature coffee extraction Cold drip uses near-zero-degree ice water for extraction, allowing the flavors in the coffee to volatilize less under low-temperature conditions and storing the coffee aroma in the coffee liquid as much as possible. When it is drunk, as the temperature of the coffee liquid rises, the aroma contained in the coffee liquid suddenly bursts out, allowing the drinker to feel a strong aroma at the back root of the tongue in the oral cavity. This sudden aroma burst gives people a great sense of happiness. The disadvantage is that the production time is relatively long, and the drip-filtered cold drip coffee cannot be drunk immediately. It must be left static in the refrigerator for more than 8 hours so that the flavor molecules extracted at low temperature can be fully released.

What difference is there in the flavor and mouthfeel performance between coffee with ice added after high-temperature extraction and coffee extracted through ice water. This time, Front Street uses Sherry coffee beans from Honduras Moca Estate to make cold drip and iced pour-over for comparison.

Front Street Coffee (FrontStreet Coffee) — Honduras Sherry Coffee Beans Estate: Honduras Moca Estate Altitude: 1500-1700m Variety: Caturra, Catuai, Pacas Processing method: Fine washed + whiskey barrel fermentation

How does Front Street Coffee (FrontStreet Coffee) make cold drip coffee? What is the coffee-to-water ratio for cold drip coffee? 1. The water-to-coffee ratio used by Front Street Coffee (FrontStreet Coffee) for cold drip is 1:10, that is, 60 grams of coffee grounds extract 600 milliliters of coffee liquid. The coffee extracted this way is relatively strong and needs to be diluted before drinking.

2. Front Street uses a TIamo cold drip pot. First, place a round filter paper at the bottom of the powder cup on the second layer, wet it with water so it adheres to the cup wall, add 60g of ground coffee (coarse sugar size), then shake the coffee surface flat. You can also use the weight of the tamper itself to lightly press the coffee bed so that the surface is level.

3. Remember to place a piece of filter paper on the coffee surface. This is because the tension of the filter paper allows water to distribute evenly. Without filter paper, long-term dripping will create a pit in the coffee bed.

4. Use ice water for "pre-infusion." This is actually similar to the blooming process in pour-over. During this process, we need to pay attention to whether the coffee surface becomes concave when water is poured for pre-infusion. If the concavity is too large, it can easily lead to uneven extraction. Therefore, during pre-infusion, water should be poured in small amounts multiple times to maintain the evenness of the coffee surface. This can improve extraction efficiency and consistency of the final product.

5. Put a 1:1 mixture of ice and water into the water container, and adjust the valve to about 7 drops every 10 seconds.

6. After production is complete, pour the coffee liquid into a sealed glass bottle and then put it in the refrigerator to ferment overnight, allowing the coffee flavors to blend together, making the mouthfeel better and easier to drink.

Why should it be put in the refrigerator to ferment overnight?

The flavor molecules of coffee just extracted at low temperature have not yet been fully released. It needs to sit static in the refrigerator for more than 8 hours to let the flavor molecules “wake up.” During the standing time, the container will produce a large amount of carbon dioxide. The pressure of carbon dioxide helps the aromatic substances and oils blend, bringing all the aromatic substances inside the coffee beans into a state where they are easy to extract.

How long can cold drip coffee be kept in the refrigerator? No matter how clean the container you store the coffee in is, Front Street here only recommends storing it for 72 hours, counted from when extraction is completed and it is poured into the container. After all, there will still be quite a few bacteria in the refrigerator. Low-temperature storage can only slow down the speed of bacterial reproduction. Generally, cold drip coffee exceeding 72 hours will deteriorate. Flavor description of Sherry cold drip coffee: Rich whiskey aroma, vanilla cream-like sweetness, and a smooth mouthfeel, followed by a light liqueur chocolate finish. How does Front Street Coffee (FrontStreet Coffee) brew iced pour-over coffee? What is the coffee-to-water ratio for iced pour-over coffee? Dripper: Hario V60 Coffee dose: 15g Coffee-to-water ratio: 1:10 Grind size: medium-fine grind (80% passing through a No. 20 standard sieve) Water temperature: 91 degrees Celsius

Preheat the dripper and sharing pitcher and rinse the filter paper. Pour the coffee grounds into the preheated dripper with filter paper, add 30g of hot water to fully wet the coffee bed into a hamburger shape, and wait 30 seconds, then proceed to the second stage of extraction. Pour water in circles from the center outward, keeping the flow stable and vertical. Foam will appear when the water stream hits the coffee bed. This stage of brewing lets the coffee foam release and spread across the entire surface of the coffee bed, with the liquid level rising to the base of the short ribs. Pour water until 90 grams in this stage, with the timer at 50 seconds.

When the water level drops to 1/2 of the coffee bed, proceed to the third stage of pouring. In this stage, also pour from the center outward in an “aroma-seeking” manner until 150g. The originally dark brown foam turns into pale yellow coffee foam, and the liquid level also returns to the height of the second pouring stage. After the coffee liquid has fully flowed into the lower pitcher, remove the dripper and end extraction. The time is 1 minute 40 seconds. Take out a second sharing pitcher, add ice cubes to fully pre-chill it, then pour out the ice cubes in the pitcher, add 100g of ice cubes again, then shake the whole pitcher of coffee liquid evenly and pour it into the second pitcher with ice cubes and stir. After the ice cubes are fully mixed, it is ready to taste.

Flavor of iced pour-over Sherry coffee: in the front section, a rich whiskey aroma; in the middle section, a soft fruit acidity, vanilla cream-like smoothness; afterward, a slight astringency and a nutty cocoa-like finish.

Through this comparison between Sherry coffee beans made as cold drip and iced pour-over, cold drip coffee can bring us an obvious sense of body while also feeling clean and refreshing, while iced pour-over can quickly extract substances from the coffee beans, giving the coffee better layering.

In addition, there is another more popular iced coffee in cafes, and that is iced Americano. Making iced Americano is actually very simple. We first grind 20g of Front Street Sherry coffee grounds, extract 40g of espresso, with the time controlled at 25-30 seconds, then prepare a glass, add 100g of ice cubes and 180g of drinking water in sequence, and finally pour the espresso over it, and it is ready to enjoy. The iced Americano made this way has a clear whiskey flavor, accompanied by vanilla, cream, and caramel notes, refreshing and full-bodied.

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The above content is compiled by CoffeeHunters, a coffee news website.