Costa Rican Coffee Bean Roasting Dehydration - Costa Rican Coffee Bean Roasting Easily Becomes Sour and Astringent

FrontStreet Coffee's Costa Rica Coffee Roasting Curve

Medium roast is the hardest range to control. Not that our light or dark roasts are flawless — but medium roast offers too many possible outcomes, too many vague, overlapping zones, with an extremely small margin for error. Take the Costa Rica Las Lajas washed we sampled today: within the Agtron #70 to #80 range, a single degree of difference is practically another world.

Our second trial curve ran a development time of 2 minutes 30 seconds and a total roast of 12:31, aiming to push the later stage. There was indeed a clear gain in body — medium-high with a smooth texture. But here came the problem: the late-palate aftertaste already showed signs of baked, roasty flavors, and the fruit acidity and aromatics turned low and dull. The late-stage development goal was met, but too crudely. As a single-origin brew it was unremarkable — overall over-roasted and flat-tasting.

Curve Three

So came the third curve. We shortened the early stage (some call it the dehydration phase, though I find that inaccurate since moisture is lost throughout the entire roast), putting the yellowing point (turn yellow, 160°C) at 5 minutes, development at 2 minutes, and total roast down to 10:38. Gentle apple acidity led into honeyed sweetness — the whole cup felt like apple juice with milk toast. When we moved to production roasting, we refined the charge temperature on this curve, lowering the turning point to 100°C while keeping the heating rhythm unchanged; total roast approached 11 minutes, and the ground-bean Agtron read #73.7.

A small personal insight: when roasting Central American coffee, don't be stingy with heat. Drive it hard — otherwise the overall taste and mouthfeel simply won't emerge. If you usually coast by cutting the heat early, you may need to operate more carefully. This kind of R&D burns through a lot of beans, so we run these trials on small-capacity machines (we currently use a Fuji Discovery) and then transfer the curves to production equipment.

For Central American coffee that doesn't naturally explode with flavor (Geisha excepted, as always), building sweetness and body is our current choice. For consumers less fond of bright fruit acidity, this style is perfect for entry and daily drinking. From our experience, most drinkers eventually graduate from these beans to other roast levels — especially light roasts — and come to understand specialty coffee in fuller dimension.

FrontStreet Coffee Recommendation

Costa Rica's honey-processed lots are a natural bridge for drinkers moving from medium roasts into brighter territory. Honey processing — Costa Rica's signature — dries the beans with part of the sugary pulp mucilage still attached, keeping washed cleanliness while adding caramel sweetness; by how much mucilage is retained, honeys run black, red, yellow, and white.

The FrontStreet Costa Rica Mozart pushes furthest with raisin honey processing: whole cherries pre-dried on raised beds for at least three days, then depulped with 100% of the mucilage retained and dried under watchful timing. Roasted to the curve above, it offers osmanthus, sweet orange, berries, pineapple, raisin, caramel, and toffee — gentle enough for daily drinking, complex enough to study. The FrontStreet Costa Rica Blackberry uses black honey, drying at least two weeks under shade covers with regular turning to prevent over-fermentation; medium-light roasted, it releases fresh-flower aromas with grape, berry, and ripe blackberry flavors.

If you would rather blend honeyed sweetness with brighter fruit, the FrontStreet Strawberry Candy Gesha Blend pairs Panama Gesha's classic orange-blossom character with raisin-honey Costa Rica coffee — grape, dried blueberry, soft acidity, an almond finish, and obvious sweetness. It brews beautifully as pour-over, works in a moka pot or espresso machine, and even makes a refreshing cold brew.