Theta Ridge Coffee LLC

Here’s one for the roasting log: Navigating the specific thermal challenges presented by the elevated density and globular morphology of the Daterra Peaberry Collection.

The Daterra Peaberry Collection represents a curated selection from one of Brazil's most methodologically advanced coffee estates. This particular offering, comprised exclusively of peaberries from Bourbon varietal trees, originates from Daterra's "Collection" group—a designation for micro-lots scoring 86-89 points, celebrated for their exceptional traceability and cup quality. The Bourbon varietal, a natural mutation of Typica, exhibits a well-documented lineage tracing back to Yemen and its subsequent propagation on Réunion Island (formerly Bourbon). While historically appreciated for its balanced cup profile and good yield, Bourbon is recognized for its susceptibility to primary coffee pathogens such as *Hemileia vastatrix* (coffee leaf rust) and coffee berry disease, necessitating diligent farm-level pathogen management.

The peaberry phenomenon, a natural mutation where only one ovule in the coffee cherry develops, results in a single, ovoid bean. This concentrated growth typically yields a bean of higher intrinsic density and distinct structural integrity compared to its flat-bean counterparts. The pulped (semi-washed) processing method employed for this lot involves the removal of the cherry skin, followed by drying with a portion of the mucilage intact. This technique, prevalent in Brazil, contributes to enhanced body and sweetness in the final cup by facilitating enzymatic reactions during the drying phase, while maintaining a cleaner profile than fully natural processes. This specific combination of high density, unique bean shape, and pulped natural processing dictates precise thermal energy application to ensure uniform heat pe*******on and complete flavor precursor development without incurring surface defects.

# # # Roaster’s Technical Notes

* **The Charge and Airflow Strategy:**
* Initiate charge at a drum temperature range of 395°F–405°F (198°C–207°C). The elevated initial energy is critical for overcoming the thermal inertia inherent in denser peaberries, promoting effective heat transfer and minimizing initial heat sink.
* Apply low initial airflow (20-25% of maximum fan capacity) during the first 2 minutes to maximize conductive heat transfer from the drum. Gradually increase airflow (to 40-50%) as bean temperature approaches the drying phase inflection point (approximately 250°F / 121°C) to facilitate moisture evacuation and manage convective heat.

* **The Maillard Phase:**
* Monitor for the transition from a pale green to a distinct yellow hue, accompanied by initial olfactory notes of toasted hay or raw legume. This indicates the onset of the Maillard reaction.
* Maintain a steady, declining Rate of Rise (ROR), aiming for 15-18°F/min (8-10°C/min) through the yellowing stage, naturally declining to 8-12°F/min (4-7°C/min) as browning progresses. Aggressive ROR management is crucial to avoid stalling, particularly with the higher sugar content typically found in pulped natural processes, which can lead to underdeveloped acidity and diminished complexity.

* **The First Crack and Finish:**
* Acoustically, the first crack will present as distinct, sharp detonations rather than a diffused popcorn-like consensus, characteristic of a denser cell structure. Note the initiation temperature and time precisely.
* Allow a Development Time Ratio (DTR) of 20-22% of total roast time, translating to approximately 90-105 seconds post-first crack initiation. This duration supports the caramelization of sugars and the full development of chocolate and nutty characteristics, aligning with the low acidity profile.
* Target a final roast degree between Full City and Full City+ (bean temperature range of 400°F–410°F / 204°C–210°C). This degree optimizes sweetness and body while preserving the delicate fruit notes suggested for espresso applications.

https://shop.thetaridgecoffee.com/

Follow this page for weekly roasting logs and technical specifications on new arrivals.

Here’s one for the roasting log: Managing thermal conductivity and moisture desorption in a dual-density, Swiss Water processed Costa Rican matrix.

The combination of Costa Rican components from Tarrazú and Valle Central introduces distinct physical variables into the drum. The Tarrazú region features volcanic soils at elevations ranging from 1,200 to 1,900 meters, predominantly planted with Caturra and Catuaí cultivars. These environmental conditions yield a Strictly Hard Bean (SHB) morphology characterized by high organic acid concentrations and a tightly knit cellular structure. Conversely, the Valle Central component originates from lower elevations (900 to 1,400 meters), resulting in a Good Hard Bean (GHB) density profile with a more open cellular matrix and high initial sucrose accumulation.

The application of the Swiss Water decaffeination process further alters these green profiles. The hydration and subsequent carbon-filter extraction process removes caffeine but weakens the cellulosic cell walls of the endosperm. This results in a bean that is more porous, highly hygroscopic, and thermally conductive than its non-decaffeinated counterparts. When blending these two regions, the roaster faces a split-density challenge: the Valle Central component risks rapid surface expansion and early pyrolysis, while the denser Tarrazú component requires sufficient thermal energy to develop the core without stalling. Color changes are also deceptive, as the green coffee carries a darker, browner baseline hue prior to charge.

Roaster’s Technical Notes
The Charge and Airflow Strategy: Charge a 1kg to 5kg commercial drum roaster at a conservative temperature range of 375°F to 385°F (190°C to 196°C) based on a 70% to 80% capacity batch. A higher charge risks scorching the compromised outer endosperm of the decaffeinated beans. Maintain low convective airflow (25% fan speed) during the first 90 seconds to allow conductive heat to pe*****te the bean core uniformly during the initial drying phase. Increase airflow to 60% immediately after the turning point to remove liberated water v***r and prevent baking the charge.

The Maillard Phase: The transition from the baseline brownish-green to a uniform pale yellow occurs between 290°F and 310°F. Sensory indicators shift from damp vegetation to toasted grain and raw legume. Manage the Rate of Rise (ROR) strictly, transitioning into the Maillard phase at 28°F to 32°F per minute, and tapering smoothly down to 18°F to 20°F per minute. Because the Swiss Water process alters the carbohydrate composition, the bean is prone to rapid, unmanageable exothermic reactions if the ROR is not systematically decelerated prior to yellowing.

The First Crack and Finish: Expect a soft, muffled, and crowded acoustic consensus rather than sharp, distinct snaps. The diminished structural integrity of the cell walls prevents the high pressure build-up typical of standard SHB coffees. Enter first crack at approximately 388°F to 392°F bean temperature. Maintain a Development Time Ratio (DTR) of 14% to 16%, dropping the batch between 75 and 85 seconds post-initiation. The target final roast degree is City+, terminating the roast at a maximum bean temperature of 412°F to 415°F to preserve the delicate malic acidity of the Tarrazú component while avoiding the bitter notes associated with advanced carbonization of the Valle Central sugars.

https://shop.thetaridgecoffee.com/

Follow this page for weekly roasting logs and technical specifications on new arrivals.