How to Enhance Sweetness Extraction in Iced Pour-Over Coffee?

The Art of Ice Pour Over: Achieving Richness and Sweetness

Compared to hot pour over, ice pour over achieves a more concentrated coffee liquid by reducing the water-to-coffee ratio, then cools and dilutes it with ice cubes. To compensate for the extraction rate lost due to reduced water, the grind size should be slightly finer than that used for hot pour over.

Even with adjustments to increase extraction rate, ice pour over still lacks the later stages of hot pour over from an extraction perspective. In other words, it's "under-extracted." Therefore, we find that when using the same coffee beans, hot pour over often excels in body, sweetness, complexity, and aftertaste compared to ice pour over.

The Challenge: Creating Rich and Sweet Iced Coffee

Some friends asked FrontStreet Coffee: Is there a way to make iced coffee that's sufficiently concentrated, possesses sweetness, yet avoids over-extraction? The requirements are indeed demanding, but it's undoubtedly a topic worth exploring.

FrontStreet Coffee has mentioned multiple times that the release points for sour, sweet, and bitter flavors occur at different times, with sweet substances often dominating in the middle to later stages. With less water and shorter extraction time in ice pour over, sweet substances may not have enough time to dissolve before the extraction process ends. Capturing the sweetness in coffee during brewing means increasing the extraction of sweet substances, which requires finding ways to give them more time to dissolve into water, thereby increasing the proportion of sweet substances in the coffee.

Coffee Selection: Costa Rica Strawberry Candy

Here, FrontStreet Coffee uses Costa Rica Strawberry Candy coffee beans as a demonstration. These beans feature strawberry candy, ripe tropical fruits, and raisin flavors, with a highly recognizable sweetness that makes them perfect for making ice pour over in summer.

Experimenting with Grind Size

FrontStreet Coffee first tried to extend extraction time by adjusting to a finer grind (EK43 setting 8.5) compared to the usual grind setting of 9.5 for daily production. With finer coffee powder, water flows more slowly, extending the extraction time. However, due to the overly fine particles causing excessive extraction, after adding ice cubes for dilution and cooling, the coffee's aroma and sweetness didn't improve, instead showing slight over-extraction with bitter aftertaste. Therefore, too fine a grind isn't feasible.

Multi-Stage Pouring Technique

Next, FrontStreet Coffee adopted another approach: more segmented pouring. Besides the bloom stage, with the same coffee-to-water ratio, more segments mean more agitation and stirring of the coffee grounds, longer total extraction time, and more substances released in each stage. However, more segments mean less water per pour, making ice pour over operation more difficult. Therefore, FrontStreet Coffee appropriately increased the distributable water amount, expanding the coffee-to-water ratio to 1:12. With increased water volume and decreased concentration, direct ice dilution would result in "tasteless" coffee, so FrontStreet Coffee used a more luxurious rapid cooling method: pouring over ice.

Experimental Parameters

Experimental parameters: 91°C water temperature, 15g coffee grounds, total water 180g, EK43 grind setting 9, four-stage pouring: 30g + 50g + 50g + 50g.

In terms of technique, FrontStreet Coffee also attempted to enhance coffee substance extraction by adjusting water flow size. First, use 30g of water for bloom for 30 seconds. For the first pour, reach 80g total, using small water flow in coin-sized circles from the center to extract bubbles;

For the second pour, reach 130g total,同样 using small water flow in outward circles, trying to rinse all the grounds; for the final pour, raise the water flow at the center point until reaching 180g total. Stop pouring at 1 minute 35 seconds, with all coffee liquid dripping completely at 2 minutes 05 seconds.

Rapid Cooling Method

Pour the extracted hot coffee over a large amount of hard ice cubes, repeating several times until the temperature drops to around 5-10°C, finally obtaining approximately 200g of iced coffee liquid.

Final Results and Serving

Then pour the coffee into a pre-chilled glass from the refrigerator to maintain the cool taste. The resulting Strawberry Candy coffee exhibits very full flavor expression, smooth texture, and clear preserved fruit sweetness. The fermented aroma resembles fruit wine, mixed with some floral notes, with a persistent aftertaste in the mouth.

Conclusion: The Philosophy of Pour Over

Of course, the approach tried here is just a result obtained according to FrontStreet Coffee's extraction logic and adjustments based on understanding this particular bean's flavor characteristics—it's not an absolute standard answer. FrontStreet Coffee believes that there's no universal brewing formula in this world. The significance of pour over lies in trying a different brewing method each time, allowing oneself to gain more novel extraction perspectives and thus appreciate the more diverse flavor aesthetics of coffee.

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Important Notice :

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Tel:020 38364473