🇺🇸 Retired veteran, father, rock-climbing expert & rosin connoisseur
Hash rosin is rosin that’s been extracted from either bubble hash or dry sift hash. The difference between hash rosin and flower rosin is in the starting material. Hash rosin is pressed from hash, and flower rosin is pressed from flowers. Hash rosin involves one additional step of solventless processing, going from cannabis flowers to hash, which increases the level of purity in the rosin as it’s extracted.
Ice Water Hash (Bubble) and Dry Sift Hash
Bubble hash, or ice water hash as it’s also called, is itself a form of solventless cannabis concentrate, made by mixing together ice water and cannabis flowers then filtering out the trichome heads that are floating around the slurry with a series of mesh screen bags. These bubble hash filter bags, also called bubble hash washing bags, are made with screens of varying sizes measuring from 25 microns to 220 micron pore sizes. Learn how to wash hash in our Guide To Washing Bubble Hash.
While ice water hash is known as the purest and highest quality form of hash, dry sift hash is the other form of hash that can deliver excellent results when pressed for rosin. In contrast to bubble hash that’s made through ice water extraction, dry sift is made by turning cannabis material over a series of mesh screens to filter out trichomes and separate out the plant contaminant. Learn more about dry sift hash and how to make it in our Ultimate Guide to Dry Sift.
Pressing Hash Rosin
Hash can be pressed for rosin in a similar way as cannabis flowers, but with some key variations. For one, hash rosin requires finer rosin filter bags in the 15-37 micron size. Since there is less plant contaminant like leftover fats and lipids present in bubble hash, we need a filter with smaller pore size to remove what little contaminant does exist. On the other hand, cannabis flowers can be pressed with rosin filter bags in the 50-90 micron sizes for an efficient extraction.
Other variables like extraction temperature and pressure should be set specifically for hash rosin. Read all about the recommended extraction specs for hash rosin in our Pressing Hash Rosin Starter Guide.
Once you’re familiar with the basics, the following list of best tips for pressing hash rosin can help refine your process.
Top 10 Hash Rosin Pressing Tips
1. Fresh frozen material will yield the lightest color hash rosin
Oxidation leads to darker trichomes, which leads to darker. While air cured buds undergo quick oxidation due to exposure to warmer temperatures and the open air, fresh frozen material is sealed in air-tight plastic bags and kept below freezing. This slows down the rate of oxidation and keeps a lighter color. Learn more about different starting material for hash in our article about Fresh Frozen vs Air Dried Cannabis.
2. Color is not necessarily the number one indicator of quality
While color can help us piece together the origin story of hash rosin, it’s not necessarily the number one indicator of overall quality. Sometimes, lighter color is achieved by harvesting premature cannabis flowers, which contain trichomes that haven’t been fully developed. These immature trichomes are much lighter than mature trichomes, and also less potent.
3. Double bag
When pressing quality hash there will be a massive flow of rosin pouring through the rosin filter bags. This outflow of rosin puts a lot of pressure on the bags, so double bagging is recommended. A 37 micron bag on the inside surrounded by a 120 or 160 micron bag on the outside is a common approach. Learn more in our article on How To Double Bag Your Rosin Bags.
4. Low and slow
Use temperatures on the low end of the scale and increase pressure slowly during extraction. 160 degrees Fahrenheit is a good temp to start. After preheating the hash between the rosin plates for about 30 seconds without exerting any pressure (just gently touching the hash to warm it), slowly begin to apply pressure. Increase pressure as you see the rosin begin to flow out of the bag, reaching maximum pressure at the end of the press. Continue pressing only until the rosin stops visibly flowing from the material.
Pre-pressing hash in a pre-press mold gets mixed reactions in the rosin community, but it’s something we recommend. Pre-pressing helps fully fill the edges and corners of the rosin bag, ensuring that there aren’t any gaps in or around the hash for rosin to become trapped. With a prepress you’re ensuring that the hash is uniform and consistent inside the filter bag, leading to the ideal rosin flow during extraction.
6. Give the hash a couple of stamps while preheating
After pre-pressing the hash in a pre-press mold, giving it a good preheat between the rosin plates and a couple of quick “stamps” is also helpful. These light stamps further prime the material for extraction, with a combination of heat and light pressure. Stamping is a quick, light press, then a quick release followed by another quick press.
7. Use directional flow with parchment paper
Directional flow is a method of folding parchment paper in a way that it directs the flow of rosin away from the heated plates and onto the hanging bit of the parchment. You can even use directional flow to let rosin drip from the parchment right into your glass jar for curing. Learn how to fold directional flow in our article about How To Use Directional Flow for Rosin.
8. Cold cure for badder, warm cure for jam
Hash rosin really comes to life after it’s been cured. There are different ways to cure rosin, either with a cold cure or a warm cure. Cold curing lets hash rosin achieve a firm and relatively homogeneous consistency, similar to a cake batter. This consistency is known as “badder”. The other main consistency that people love is rosin jam, or sauce. This is achieved with a warm cure.
9. Minimize moisture content by ensuring hash is fully dry before pressing
Unlike pressing flowers for rosin, hash should be totally dry before being pressed. Flowers are good to press between 60-65% relative humidity, but hash should be a lot drier. When hash reaches the consistency of grains of sand that don’t stick together, it’s the perfect dryness for pressing.
10. Live rosin optimizes for taste, while yield can be better with cured material
If the best taste is your goal for hash rosin, using fresh frozen material to create hash rosin is the best way. Hash made from fresh frozen material is known as live rosin. However, if yield is your main concern, washing air cured flowers for hash is often the way to increase yield.
Hash rosin is the premium solventless product, and one of the most sought-after cannabis concentrates available today. In our view, it’s only going to gain in popularity. Gaining experience making hash rosin is one of the most valuable advantages for a solventless extractor.
What additional tips do you have for making the best hash rosin? Let us know in the comments!
FREQUENTLY ASKED QUESTIONS
What is stamping?
Stamping is applying quick, light presses onto the material between heated rosin plates. Apply pressure, release, then apply pressure again in rapid sequence.
Why is directional flow best for hash rosin?
Directional flow works best for hash rosin in order to control the massive flow of rosin from the source material. Pressing hash generates a larger flow of rosin than pressing flowers, which is why directional flow is more important for pressing hash.
What causes the great taste in hash rosin?
The terpenes in rosin are what gives the rosin its great taste. Hash rosin contains high concentrations of terpenes, especially if it’s hash made from fresh frozen material.
What is oxidation?
Oxidation is a chemical transformation that occurs when an oxygen molecule is added to an existing compound. Oxidation degrades cannabis, though it is a natural occurrence that will happen over time.
Is rosin badder superior to rosin jam?
No, one is not better than the other. It’s all about which rosin consistency you prefer. Cold curing can make badder and warm curing can make jam.