THERMAL SHOCK - Ruby Pulse - Kalyancool Estate (In-House)

About this coffee

Kalyancool Thermal Shock Fermentation – Ruby Pulse. This is one of the most technically experimental microlots we have produced this year—an expressive coffee that demonstrates how extreme temperature contrast and controlled fermentation can unlock deep fruit complexity and wine-like character. Rooted in our own estate at Kalyancool, this microlot explores the effect of thermal shock processing combined with controlled yeast fermentation. Carefully selected fully ripened red cherries are first sorted to remove floaters and underripe fruits, ensuring only dense, high-quality cherries enter the process. The cherries are then subjected to a thermal shock treatment, where they are immersed in 55°C warm water for 5 minutes. This controlled heat exposure helps soften the fruit structure and prepares the cherries for rapid cellular stress. Immediately after heating, the cherries are transferred to ice chamber and rapidly chilled, remaining in the cold bath for around 7–8 minutes. This dramatic temperature contrast creates a "thermal shock" effect that enhances permeability of the fruit and intensifies the interaction between sugars, microbes, and yeast during fermentation. After the thermal treatment, the cherries are gently bruised to create a bruised natural process, allowing partial opening of the fruit skin while maintaining the natural mucilage and pulp around the beans. The cherries are then inoculated with activated Lalcafe Intenso yeast, a strain chosen for its ability to enhance fruity aromatics and wine-like complexity. Fermentation takes place in sealed Eco-tact bags for 72 hours, allowing controlled anaerobic conditions to develop layered fruit character. Once fermentation is complete, the coffee is dried as naturals and carefully light (light plus) roasted to preserve clarity, acidity, and aromatic intensity. This is a bold experimental coffee designed to showcase how thermal shock processing and precision fermentation can transform natural coffees into intensely fruit-driven microlots.