Alejo Castro Kahle is a descendant of coffee pioneers in Costa Rica. He is committed to honoring the legacy of his ancestors through the continued pursuit of their aim — producing excellent coffees and making the family's name known for it worldwide.
To ensure consistent quality and make way for improvement every year, he is involved in every step of production, from the establishment of the coffee plants, cherry harvest, fermentation and drying, until dry milling and loading the greens into containers for export.
With 200 years of heritage knowledge in coffee, Alejo is vocal about soil health as the cornerstone of cultivating coffee trees that yield cherries with well-developed beans having the potential for complex flavors. He implements only processing innovations that preserve the integrity of variety while highlighting its most desirable attributes and reflecting its provenance.
Volcan Azul is the flagship estate of the Castro Kahle family. It spans 300 hectares on the slopes of the Poas Volcano, of which 60 hectares are planted, and 200 hectares are dedicated to conservation. There are 40+ varieties grown on the farm, of which Geisha, Typica, SL 28, Caturra, and San Isidro have won at the COE.
SL 28 is among the better known varieties that originated in East Africa and is most notably regarded for its characteristic bright, bold, and heavy-bodied cup profile. The SL 28 grown at Volcan Azul has taken 4th place at the Cup of Excellence and has also been featured by World Barista and World Brewers Cup competitors.
Quality production starts with ensuring nutrient-rich soil and protection from diseases that will allow healthy coffee trees to grow. This is a cyclical exercise carried out consistently to maintain and build on the gains from the previous years. At the time of harvest, only cherries at peak ripeness are hand-picked. These are cherries whose mucilage registers at least 22% on the Brix meter, indicating optimal sugar content and allowing Alejo the flexibility to select the most suitable fermentation and drying techniques to produce the desired cup attributes.
To anchor the vibrant and complex acidity of SL 28 in a rich sweetness, a Natural Anaerobic process was used. The cherries were placed in sealed tanks with a valve allowing oxygen to exit and be replaced by CO2. Time, temperature, and acidity and sugar content of the mucilage were monitored until the intended levels were achieved.