INFUSED PRE-ROLL EDUCATION
What Is a Hash Hole? A Guide to Hash Hole Joints
September 2026 · 7 min read
Author: Erik Blackerby
A hash hole is an infused pre-roll made with a core of cannabis concentrate running through the center of the flower. As it burns, that center core creates the distinctive opening that gives the hash hole its name.
You may also hear these pre-rolls called donut joints, donut holes or rosin donuts. The terminology varies from brand to brand, but the basic construction is similar: flower surrounds a concentrated core positioned through the center of the joint.
Hash holes started largely as a hand-crafted product, but their popularity has created a new challenge for cannabis manufacturers. Making a few by hand is one thing. Producing hundreds or thousands with consistent concentrate dosing and placement is something entirely different.
In This Guide
- What Is Inside a Hash Hole?
- Why Is It Called a Hash Hole or Donut Joint?
- Hash Hole vs. Infused Pre-Roll
- What Concentrates Are Used in Hash Holes?
- How Are Hash Holes Traditionally Made?
- What Makes a Consistent Hash Hole?
- Why Are Hash Holes Difficult to Produce at Scale?
- How Does a Pre-Roll Infusion Machine Work?
- Automating Hash Hole Production
- Hash Hole FAQs
- Hand-rolled-to-commercial-production
What Is a Hash Hole?
A hash hole has three basic components: the rolling paper or pre-rolled cone, cannabis flower, and an internal concentrate core.
Unlike some other infused pre-rolls, where concentrate may be incorporated throughout the flower or added using another infusion method, a hash hole is defined by the concentrate positioned inside the flower as a core.
The exact formulation varies. Producers may use different amounts of flower and concentrate, different concentrate types, and different core positions depending on the product they’re trying to make.
Why Is It Called a Hash Hole or Donut Joint?
The names come from what happens at the center of the joint as it burns.
Because the concentrate is positioned through the middle of the flower, the burning end can develop a distinctive opening or ring in the center. That appearance led to names such as hash hole and donut joint.
The terms are often used interchangeably, although individual brands may use them differently.
Rosin is especially associated with traditional hash holes, which is also why you’ll sometimes hear the term rosin donut.
Regardless of the name, the important characteristic is the same: a concentrated internal core surrounded by flower.
How Is a Hash Hole Different From an Infused Pre-Roll?
Every hash hole is an infused pre-roll, but not every infused pre-roll is a hash hole.
An infused pre-roll is a broad product category. Concentrate can be incorporated into a pre-roll in different ways depending on the formulation and manufacturing process.
A hash hole is a more specific style of infused pre-roll because the concentrate is intentionally positioned as an internal core.
What Concentrates Are Used in Hash Hole Joints?
Hash holes have traditionally been made by hand.
Flower is prepared for the joint and concentrate is portioned into a narrow core. The flower is then formed around that concentrate so the core remains positioned through the center.
For small batches, an experienced operator can have a lot of control over the finished product.
But hand production is heavily dependent on the person making it.
Small differences in concentrate amount, placement, flower fill and handling may not seem significant when making a handful of joints. When a producer needs to make hundreds or thousands, those small differences become much more important.
That’s where the challenge shifts from simply making a hash hole to developing a repeatable production process.
How Are Hash Holes Made?
Hash holes have traditionally been made by hand.
Flower is prepared for the joint and concentrate is portioned into a narrow core. The flower is then formed around that concentrate so the core remains positioned through the center.
For small batches, an experienced operator can have a lot of control over the finished product.
But hand production is heavily dependent on the person making it.
Small differences in concentrate amount, placement, flower fill and handling may not seem significant when making a handful of joints. When a producer needs to make hundreds or thousands, those small differences become much more important.
That’s where the challenge shifts from simply making a hash hole to developing a repeatable production process.
What Makes a Consistent Hash Hole?
The problem isn’t simply speed.
It’s maintaining control while increasing output.
If concentrate is manually portioned and positioned in every pre-roll, increasing production often means adding more operators. More operators can also introduce more variation into the process.
Manufacturers have to balance:
- concentrate dosing
- core placement
- material temperature and viscosity
- pre-roll consistency
- labor
- throughput
- repeatability
That can make infusion one of the bottlenecks in an otherwise automated pre-roll production line.
A producer may already be grinding flower, filling cones, checking weights and closing pre-rolls with commercial equipment, only to reach the infusion step and return to a largely manual process.
That’s the production problem pre-roll infusion equipment is designed to address.
Why Are Hash Holes Difficult to Produce at Scale?
The hard part isn’t simply getting concentrate into a pre-roll.
It’s doing it consistently, accurately and repeatedly.
If concentrate doses vary, finished product weights and formulations can vary. If the core isn’t positioned correctly, the finished product can change. And if every pre-roll requires individual handling, increasing production usually means increasing labor.
Commercial producers therefore have to manage several variables at the same time:
- Concentrate dose
- Core placement
- Concentrate temperature and viscosity
- Pre-roll consistency
- Production throughput
- Labor
- Repeatability
These differences may be manageable when producing a small number of joints. At commercial volumes, they can become a production bottleneck.
This is why infused pre-roll production is increasingly becoming its own manufacturing process rather than simply another variation of conventional pre-roll filling.
How Does a Pre-Roll Infusion Machine Work?
A pre-roll infusion machine automates the process of dispensing a measured amount of compatible concentrate into filled pre-rolls.
Instead of an operator manually portioning and positioning concentrate in every joint, the machine controls variables such as dose, temperature and concentrate placement.
Different infusion systems approach this process differently. Some process individual pre-rolls or smaller groups, while others are designed around trays and larger production workflows.
For commercial producers, the goal isn’t simply to make the machine move faster. It’s to make concentrate placement more controlled and repeatable across a production run.
Automating Hash Hole Production With the Astro Infuser 2.0
STM Canna developed the Astro Infuser 2.0 for commercial producers that need to automate internal pre-roll infusion.
The system uses 12 simultaneous injection points to dispense compatible concentrate into filled pre-rolls. Operators can program the concentrate dose, control temperature, and adjust where the internal core starts and stops within the pre-roll.
A 72-count tray can be processed in approximately 90 seconds of machine cycle time, with compatible concentrates including rosin, live resin and distillate.
The Astro doesn’t replace the entire pre-roll production process. Flower still needs to be prepared and filled, concentrate needs to be prepared for infusion, trays need to be handled, and finished products still require quality control.
What it automates is one of the difficult steps to repeat manually at commercial volume: controlled concentrate dosing and internal core placement.
Hash Hole FAQs
What is a hash hole?
A hash hole is an infused pre-roll with a cannabis concentrate core positioned through the center of the flower. The name comes from the distinctive opening that can form in the center as the joint burns.
What is a donut joint?
A donut joint is another common term for a hash-hole-style joint with a concentrate core surrounded by flower. The terms hash hole and donut joint are often used interchangeably.
Are all infused pre-rolls hash holes?
No. A hash hole is one specific type of infused pre-roll. Other infused pre-rolls can incorporate concentrate using different formulations and infusion methods.
Are hash holes always made with rosin?
No. Rosin is closely associated with traditional hash holes and rosin donuts, but commercial infused pre-rolls can use other compatible concentrates depending on the product and production process.
Can hash holes be made with a machine?
Yes. A commercial hash hole machine or pre-roll infuser can automate concentrate dosing and internal core placement. This allows producers to scale hash hole production without manually positioning concentrate inside every individual pre-roll.
What's the difference between a hash hole and a donut joint?
There generally isn’t a fundamental difference. Both terms commonly describe an infused joint with a concentrate core surrounded by flower. Individual brands may use the terminology differently.
Hash holes grew out of craft cannabis culture, and hand-made products remain an important part of the category.
But increasing demand changes the production problem.
Once a manufacturer needs to produce hundreds or thousands of infused pre-rolls, the challenge becomes maintaining control over dose, core placement and product consistency while increasing throughput.
That’s where automation begins to make sense.
Commercial pre-roll infusion equipment allows manufacturers to take a process traditionally performed one joint at a time and integrate it into a larger pre-roll production workflow.
For producers evaluating how to scale hash holes, donut joints or other internally infused pre-rolls, the Astro Infuser 2.0 provides a way to automate concentrate dosing and core placement while working within STM Canna’s broader pre-roll production system.
