🇺🇸 Retired veteran, father, rock-climbing expert & rosin connoisseur
There are multiple variables that can impact the color of rosin. Characteristics of the source material, extraction specs, and storage methods can all impact color. As a general rule, the lighter the rosin the higher the perception of quality. Therefore, extractors prioritize color to increase demand for the product.
Let’s take a look at each of these color-impacting categories and what we can do to produce and maintain lighter rosin.
Characteristics of Starting Material
The age of the starting material for pressing rosin is one of the most impactful variables for color. As cannabis ages the trichome heads oxidize, bringing about changes in cannabinoid and terpene content. Oxidation is a natural process that can be slowed but not stopped. As material oxidizes its main active ingredients begin to transform into less active forms and therapeutic value diminishes. With this loss of potency comes a darkening of color.
How the source material was dried prior to pressing also impacts color. Ice water hash dried in a freeze dryer will come out lighter than air-dried hash. Air drying can take days, but freeze drying only takes 24 hours or less. This short drying time helps preserve the color of the trichomes and prevent additional darkening through oxidation.
Another quality of hash that impacts rosin color is the type of flower used in hash production. Air dried flowers will generally produce a darker hash than fresh frozen flowers due to oxidation that occurs with exposure to air.
The drying time for flower also impacts the levels of oxidation present. Shorter drying times preserve trichome color, while longer cures invite oxidation. Flower should be dried only for a few days, until the buds contain the right amount of moisture for pressing. Too wet and there will be excessive moisture in the rosin. Too dry and rosin yield will suffer. Hang fresh cannabis to dry until the flower contains 60-65% humidity (RH).
The point of ripeness at which the cannabis flower was harvested is another characteristic of starting material that impacts color. The color of trichome heads changes throughout the grow cycle, from clear to milky to amber. A clear trichome head is not ripe, while a fully amber trichome head is past its prime. The ideal ripeness occurs as the trichome head moves from milky to amber. This amber color leads to the golden hue in rosin.
To keep rosin as light and clear as possible, some growers harvest cannabis before it’s fully ripe, meaning the trichome heads are mostly clear. All-clear trichome heads will produce lighter rosin than ripe or overly-ripe heads. But just because the trichomes are at a later stage of ripeness, and therefore a darker color, doesn’t mean they are poor quality. Ripeness is a matter of personal preference. But one thing is for sure, trichome heads that haven’t been allowed to fully ripen will not be as psychoactive. So in this way, a light rosin due to unripe trichomes isn’t as powerful as a darker rosin that contains mature heads.
Finally, the genetics of the cultivar you’re working with also plays a role in color. The ratio of various components of the resin glands, much of which is determined by plant genetics, can determine the resulting color of rosin.
Rosin Press Settings
Like the attributes of source material, time and temperature settings of extraction also affect the color of rosin. Keep in mind the temperature recommendations are different for flower rosin than for hash rosin.
Applying higher temperatures during extraction produces darker rosin than using temperatures at the lower side of the spectrum. Even if the starting material contains light trichome heads, excessively high temperatures approaching 220 degrees or higher can darken rosin. Lower temperatures, especially with hash, are better for preserving a lighter color.
Likewise, long exposure time to high temperatures can create a darker rosin. Rosin should flow quickly from between the heated press plates and onto the cool parchment paper. The longer that the rosin is exposed to heat, the darker it becomes. Keep pressing time to a minimum without sacrificing too much yield. Fold your parchment paper to optimize directional flow so that the rosin can quickly move away from the heat as soon as it’s extracted. Continue pressing only until the flow of rosin through the filter bag stops.
Excessive pressure can also force contaminants through the rosin filter bag during extraction, which leads to darker rosin. Don’t use more pressure than needed, and increase pressure slowly. It may be worth sacrificing a bit of yield for some lighter rosin.
The longer your starting material is exposed to high heat and pressure, the more likely it will be darkened. Experiment with reducing your time, temp, and pressure settings for both flower rosin and hash rosin to lighten the color.
Finally, if rosin is taking on a greenish tone, this is a sign of chlorophyll contamination. If pressing flower, try applying pressure more slowly and reducing the maximum amount of pressure used. You can also try using a smaller micron filter bag, like a 90, 75, or even 50 micron.
If you’re pressing hash, evaluate your hash-making process to reduce the amount of contamination you’re collecting with the trichome heads. Often, using less force while agitating the cannabis and ice water can reduce chlorophyll contamination.
We know that oxidation is a natural process brought about through exposure to air, and that it darkens the color of cannabis. The best storage methods reduce air exposure and maintain the color of cannabis for longer.
Storing rosin in air-tight glass jars, or even vacuum sealing the containers in which you have the cannabis stored, will preserve its light color and slow down the darkening. Rosin that starts out light will become darker in color if left in the open air for storage, or even inside of a container that’s not completely sealed to keep out oxygen.
What Can You Do To Get Lighter Rosin
Harvesting cannabis at or slightly before peak ripeness, running fresh frozen instead of air dried flowers for hash production, drying bubble hash using a freeze dryer, pressing rosin with lower temperatures, avoiding starting material that’s aged, and properly storing both starting material and rosin in air tight or vacuum sealed containers will help you achieve lighter rosin.
One trick made popular for Instagram photos is to whip rosin, bringing about a lighter color in the short term. Whipping rosin isn’t all about color change though, it has other benefits like stabilizing consistency. However right after you whip rosin, you’ll often notice a lighter color right away. This won’t last indefinitely though, as whipping increases oxidation and will quicken the darkening in color in the mid to long term. So if a pic of some light blond is your goal, you can whip rosin for a quick fix.
Learn more about whipping rosin and why it’s a popular technique in our article all about the benefits of whipping rosin.
Color is likely the first characteristic most people notice when looking at a batch of rosin, but it doesn’t tell the whole story. Consider color a first impression at best, but don’t judge a rosin only by its color.
Color is undeniably linked to the perception of quality. So keep the darker stuff for your head stash if you must, it’s often just as good if not better than some of the light blond batches. It’s not all about appearance.
FREQUENTLY ASKED QUESTIONS
Why is my rosin dark?
There are many factors that can contribute to dark rosin that include using aged and oxidized starting material, pressing hash that contains excess contaminants, using excessive heat, time, and pressure to press rosin, and storing rosin improperly.
Is dark rosin bad?
Not necessarily. Dark rosin can still be very high quality, depending on which factors contributed to the darker color. For example, using dark, low quality, contaminated ice water hash won’t make a high quality hash rosin.
Is light color rosin the best rosin?
Light color in rosin is perceived as being higher quality, containing fewer contaminants. However, if light color is achieved through harvesting trichome heads before they are fully mature, then the quality in rosin will suffer. In this case, light rosin is not the best rosin.
How can I make my rosin look lighter?
Using fresh, high quality source material, pressing rosin with the correct extraction techniques, and storing rosin properly will maintain lighter color. Also, you can whip rosin to quickly make a lighter color, although this will not last in the long term.
Why does my rosin look green?
Green rosin is a sign of chlorophyll contamination. This means that plant matter has made its way into your extract.