Experimental drying and curing comparisons, moisture redistribution, cannabinoid measurements, color, and microbial levels.
Harvest & Post-Harvest
Water Activity & Moisture Equilibration
Water activity describes the availability of water for chemical and microbial processes and is not the same measurement as total moisture content.
Key concepts
- Two samples with similar moisture content can have different water activity
- Moisture redistributes within stored flower after packaging
- Equilibration takes time
- Microbial risk depends strongly on available water
What to measure or observe
- Use a calibrated water-activity meter when precise control is required
- Allow representative samples to equilibrate before interpreting readings
- Track readings across a lot rather than one flower when uniformity is uncertain
Common mistakes
- Treating container RH as identical to a validated water-activity measurement
- Assuming one reading represents an uneven batch
- Confusing water activity with percent moisture
Visuals this lesson still needs
- Water activity versus moisture content diagram
- Equilibration sequence
- Sampling workflow
- Microbial-risk concept chart
Evidence & further reading
Sources connected to this lesson
These references support specific biological, diagnostic, environmental, or process concepts used in this lesson. They are not a substitute for crop-specific testing or local regulatory guidance.Cannabis inflorescence microbial loads, microclimate, airflow, handling, drying method, moisture, water activity, and post-harvest risk factors.
Drying, curing, storage, water activity, equilibrium moisture, packaging, and post-harvest process design.