Cannabis enthusiast and student of the art of solventless extraction
Cold curing continues to be a hot topic in rosin, consistently delivering results that speak for themselves. Curing is the final step in rosin production, and it’s the chance to see the stunning results of chemistry in action. Cold curing creates the right environment for rosin to transform in texture and consistency, often from a greasy sap to a nice firm batter. The right cure can bring about both depth and subtlety in flavor that doesn’t exist in “right off the press” rosin dabs, and help amplify the nose.
What is Cold Curing?
Cold curing is the process of enabling freshly-made rosin to transform its consistency via interactions of terpenes and cannabinoids in a self-contained environment. Cold curing starts in the low 60-degree range and lasts anywhere from one to three days, to even a week or more.
Cold curing is comparable to other forms of curing in cannabis, like curing dried flowers after the harvest. This last bit of preparation, when the product is technically ready to consume but isn’t quite optimized, can actually make all the difference. And similar to curing cannabis flowers, all you need for cold curing rosin is a sealable jar and temperature control. With minimal preparation and virtually zero labor while curing, it’s really a fantastic improvement for very little effort.
Cold curing is considered a form of Jar Tech, which is the broader term for curing rosin in sealed glass jars. You can read about the step by step of using this method in our article about How To Jar Tech Rosin.
Warm curing is the alternative to cold curing, and the other type of Jar Tech that uses higher heat during the cure. Learn more in our article about the differences between warm and cold curing.
Cold curing doesn’t even require temperatures that you may otherwise think of as “cold”. Even a slightly cool room temperature will do! Household refrigerators are optional, and can certainly be beneficial for experimentation sake. Sometimes rosin does better curing in the refrigerator, with the rate of evaporation of terpenes and nucleation of THC slowed down at lower temperatures. A lot depends on the cultivar you’re working with, source material used, etc.
That said, if you’re working with flower rosin as opposed to hash rosin, then look to cold curing as the ideal cure. While hash rosin is generally well-suited for either warm or cold cures, flower rosin often doesn’t perform as well with a warm cure treatment. So give your flower rosin the cold cure it deserves!
Now let’s look at our top tips for cold curing rosin.
#1 Keep the glass jar completely sealed while curing
Avoid losing terpenes by keeping an air-tight seal on the jar. Use only glass jars that are sealed with a reliable gasket of some sort. Eliminating air flow inside the jar will prevent excess loss of terpenes. If you remove the lid to "burp and stir" at intervals during an extended cure, be sure to reseal.
#2 When cold curing in the refrigerator or below room temp, let the jar come to room temp before removing lid.
This reduces the amount of condensation present in the jar. Once it's back to room temp, carefully wipe away any moisture that collects along the inner surface of the jar around the opening. The goal is to avoid letting any moisture into the rosin!
#3 Wine coolers
Not the fruity wine drinks! Wine coolers are small refrigerators that keep temps ideal for storing wine (around 40 degrees). This is also a nice temperature range for cold curing rosin.
As rosin cures, the terpenes will separate themselves and form tiny little pools within the rosin. To achieve a batter-like consistency (which is often the end goal for a cold cure), recombining these puddles of terpenes back into the mix is essential. Use a cold dab tool and whip the rosin like you'd whip egg whites, agitating the rosin with quick circular motions of the wrist.
#5 Use straight-sided jars for curing
A jar with straight sides from bottom to top makes rosin collection after the cure much easier. Tapered sides with an opening more narrow than the base of the jar makes maneuvering a dab tool for collecting the rosin a little more tricky.
#6 Minimize empty space in the jar
Try not to leave more than one inch at the top of the jar between the level of the rosin and the lid. Keeping the extra space at the top to a minimum is better for the curing process because it means less oxidation of cannabinoids. It also keeps terpene evaporation at lower levels. 1oz jars from Uline are ideal.
#7 After 72 hours give it a whip
Three days is a good time to open the jar and check the rosin. Whip the concentrate to recombine the terpenes and see what kind of consistency you end up with. Depending on your preference, you can end the cure at this time or keep it going for a few more days.
#8 Keep in a dark place while curing
Light degrades cannabinoids, so always cure in a dark space. If needed you can put the jars in an opaque container to block out the light while curing. A closet works nicely as well, and can provide a cooler space due to lack of windows (depending on the season and where you live!).
#9 Flower rosin normally does better with a cold cure than a warm cure
Hash rosin can respond better to warm cures by nucleating in a drastic, stunning way. Flower rosin is better suited for a cold cure.
The cannabis cultivar used to produce the rosin, the type of source material, and age of the material all contribute to the way that a specific batch of rosin will cure. Try different lengths of time for the cure, change up the number of times and frequency that you whip the rosin, and adjust the temperatures to see what works best. And keep good notes!
Rosin is an incredibly dynamic cannabis concentrate and it can take on many different looks and feels. The cure is an opportunity for extractors to bring about the final phase change that characterizes top shelf rosin.
With all the variables that impact the final outcome, experimentation is one of the best approaches to take. Use these top tips and see what works best for you.
FREQUENTLY ASKED QUESTIONS
What is a mason jar?
A mason jar is a molded glass jar with a air-tight sealable lid traditionally used for canning/preserving food. They are also perfect for curing and storing cannabis.
What is whipping rosin?
Whipping is beating rosin vigorously with quick, circular motions in order to incorporate air. Whipping causes changes in terpene content, brings on a level of oxidation, and in the process transforms consistency into a batter-like concentrate.
What is a wine cooler?
Small capacity refrigerators made specifically for storing wine. They keep temperatures around 40-ish degrees which is perfect for cold curing rosin.
Why does condensation occur inside the jar during cold curing?
If you're cold curing rosin inside a refrigerator, condensation is likely to occur around the inner surfaces of the glass jar. This happens once the jar is removed from the refrigerator and starts to warm up to the temperatures of the surrounding air. This warming up brings the air inside the jar to the dew point in which moisture in the air condenses along the inside of the glass. This should be thoroughly wiped away so it doesn't mix with the rosin.
What temperatures should I use when cold curing rosin?
A good range to aim for is 40-60 degrees. So even a cooler room temperature will do just fine. No need for a freezer.