Gene Café CBR 301 | House Espresso Journey | Finding My Sweet Spot Before Chasing Consistency

When I started roasting espresso on the Gene Café CBR-301, I thought I was looking for a magic number — the “perfect roast level.” What I discovered instead was something more useful: a range. In this video, I walk through my full house espresso journey so far — testing lighter roasts, pushing darker to 18% weight loss, and finally narrowing down a balanced, drinkable lane around 16–16.5% weight loss on Brazil Santos. This isn’t about chasing tasting notes like jasmine or blackcurrant. It’s about structure: Acidity control Body Roast character Milk performance Everyday drinkability I compare roasts around 16.5% and 17% weight loss, discuss extraction variables (35s vs 39s shots), and explain why I’m no longer chasing fireworks — just stability. Most importantly, this sets up the next phase of the journey: Between-batch consistency. Because finding a sweet spot once is one thing. Repeating it across multiple batches on the Gene Café CBR-301 is something else entirely. If you’re roasting at home, building a house espresso profile, or trying to understand weight loss percentages on the Gene Café, this video documents the process honestly — including the boundaries that didn’t work (18% was clearly too far for me). Next up: designing a repeatable between-batch protocol to control thermal behaviour and stay inside a chosen roast lane. ☕ Topics Covered Gene Café CBR-301 espresso roasting Weight loss percentage and espresso balance 16% vs 17% roast comparison Over-roasting at 18% WL Extraction influence on taste Defining a house espresso profile Repeatability vs perfection in home roasting If this kind of calm, engineering-led home roasting journey interests you, consider subscribing and following along as we explore consistency, airflow, and between-batch control on the Gene Café CBR-301. ⏱ Chapters 00:00 – Intro: Chasing the “Perfect” Espresso 00:46 – Roasting Range vs Magic Numbers 01:06 – Pushing Lighter: Acidity Observations 01:19 – Pushing Darker: 18% Weight Loss Boundary 01:46 – Settling into the Mid-16% Range 01:56 – 16.5% vs 17% Side-by-Side Comparison 02:08 – Extraction Differences (35s vs 39s) 02:22 – What Actually Matters: Stability Over Fireworks 02:35 – Defining My House Espresso Lane (16–16.5%) 03:00 – The Real Question: Can I Repeat It? 03:10 – Warm Starts and Thermal Behaviour on the Gene Café 03:31 – Between-Batch Control and Consistency 03:56 – Next Chapter: Repeatability, Not Perfection