The patent-pending Softrim™ de-leafing technology was developed by manufacturing engineers outside of the cannabis industry. Their focus was to industrialize the process and build production equipment that matched hand-trim yield and quality, but at a much higher speed.
During their research and development, they also learned that the cannabis industry had several different post-harvest practices, most founded on one of two approaches: batch processing and single-piece-flow processing.
This paper provides their analysis of the most cost-effective of these approaches, and the de-leafing advantages of Softrim technology when integrated with it.
Batch Processing Method and De-leafing
The agricultural industry typically uses batch processing for bulk goods. In the case of cannabis, volume manufacturers buck dried product into a tote, which gets staged in a room for trimming. A tote is then selected, opened, and the bucked flower placed into a blade drum tumbler for de-leafing. Here the outside edge of the flowers on the outside edge of the drum gets trimmed first and the inside material randomly waits to get trimmed last. When all of the material is trimmed the process ends. As a result during de-leafing, some of the material is unnecessarily trimmed repeatedly.
At that point, the trimmed flower material is stored in a tote. Finally, the tote is transferred to the hand trimming room, where the flowers are sorted and manicured for final quality control (removing all remaining sugar leaves, crow’s feet ,and stems). The final product tote is then staged in a room until retrieved to fulfill a customer order.
What is Homogenization, Why Does It Occur in Batch Processing and How does it Ultimately affect De-leafing?
While the cannabis hangs in the dry room in advance of bucking, the thin sugar leaves become brittle, containing approximately 10% moisture content. At the same time, the inner-core bud has around 12-14% moisture content.
However, once the dried flower is placed into a tote awaiting the de-leafing process and a lid attached, a process called homogenization occurs. This is where the 10% moisture-content sugar leaves start to absorb the 14% moisture from the core of the bud. Depending on when the tote is pulled from the staging area, the sugar leaves and buds in the core center of the tote will have a different moisture content than the product on the outer edges of the tote. The result is inconsistently dried flowers, many with tightly coupled leaves. These leaves are difficult to remove by hand and take a great deal of time to manicure to a final product.
Single Piece Flow Processing and De-leafing
After studying the two alternative trim processes, Softrim engineers chose to develop a highly reliable, high-volume single-piece-flow approach to cannabis trimming. Such a process provides every individual flower the same de-leafing treatment, allowing the grower to achieve – or exceed – hand-trim quality using an automated de-leafing process. (Note: on demand, Softrim can be integrated with batch processing, but results are optimal with single piece flow.)
First, plants are hung upside down in a controlled humidity-and-temperature dry room for 7-12 days. Next, the Softrim machine is brought directly into the dry room. At this time, the humidity is turned down by 5% (if the facility is drying at 55%, at this point the facility would drop the humidity to 50%). This maintains the appropriate dryness in the room, compensating for the moisture that the staff introduce by entering and exiting the room. As the staff bucks flower off the stock to fill totes, they then deliver the totes directly to the incoming funnel of a Softrim machine placed inside the dry room. In this way, Softrim uses a linear single-piece-flow philosophy, rather than the randomly selected totes used with blade tumblers for de-leafing.
With Softrim, the bucked flower is pulled into the processing area by the thousands of engineered silicone fingers on the belts. This ensures that each flower gets the same de-leafing treatment as it travels linearly through the Softrim machine. The average processing time to deleaf one pound of flower is 20 seconds, so an average 6-pound tote takes two minutes to de-leaf.
With most strains, and with proper humidity control, the Softrim process is capable of producing nearly ready-to-package flowers. In some implementations, customers have achieved 90%-plus salable product, with only about 10% of the flowers requiring post-Softrim quality control; this largely depends on the quality of hand bucking.
In Summary
While each cultivation facility has slightly different practices, Softrim can work with its customers to reduce process steps. As shown below, the Softrim process coupled with the single-piece-flow process yields reductions in floor space, floor traffic, labor, and a decline in product tracking tasks.
