89°C vs 92°C Water: Which Brews Medium-Roast Coffee Better?

 

Why Water Temperature Affects Drip Coffee Flavor

Hotter water extracts compounds from coffee faster and more thoroughly — both the sweet, caramelized compounds developed during roasting and the compounds that create bitterness. The outcome depends on which compounds the roast has developed more of.

Most drip brewing guides recommend 90–92°C for medium roasts, but many home brewers wonder how much a small drop in temperature actually changes the cup.

 

The Test: Brewing Fullcity Roast at 89°C vs 92°C

Preda’s team tested this using Fullcity Roast, the brand’s classic medium roast. Two cups were brewed with identical technique — medium grind (about the size of raw cane sugar), 20g of coffee, a V60 dripper, a 1:15 ratio (300ml water), finishing within 2.5 minutes. The only variable was water temperature: 89°C versus 92°C.

Preda’s cuppers tasted both cups blind, without knowing which was which. The 92°C cup was preferred: fuller flavor and a longer, sweeter aftertaste than the 89°C cup.

 

When to Brew Hotter, When to Brew Cooler

The 92°C water didn’t make Fullcity Roast taste more bitter because Preda’s roast profile already develops high-quality caramel sweetness with low bitterness. Extracting faster with hotter water pulls out more of that sweetness without a bitterness penalty.

The takeaway: if a coffee is roasted for low bitterness and well-developed caramel sweetness, you can push the water temperature higher as the roast level gets darker. If a coffee already carries noticeable bitterness, lowering the water temperature helps keep that in check. These specific numbers are calibrated to Preda’s roast profile — beans from other roasters may behave differently.

 

Frequently Asked Questions (FAQ)

 

Q1. Does hotter water always make coffee more bitter?

Not necessarily — it depends on the roast profile. If a coffee is roasted for low bitterness and well-developed caramel sweetness, hotter water extracts more sweetness without adding bitterness.

 

Q2. What water temperature should I use for Preda’s medium roasts?

Start at 90–92°C, per the roastery’s brewing guide, then adjust to personal taste.

 

Q3. What brew ratio was used in the test?

A 1:15 ratio (20g coffee to 300ml water), medium grind, V60 dripper, finishing within 2.5 minutes.

 

Q4. Does this rule apply to medium roasts from other roasteries?

The general principle — temperature affects extraction rate — applies broadly, but the specific numbers here are calibrated to Preda’s roast profile and may not transfer directly to other roasters’ beans.