Aging, Artifacts, And The Art Of Curing Cannabis
Aged and cured cannabis are old, traditional methodologies which hashishins have practiced for generations. As cannabis is unlike the grapes of wine, the apples of cider, and the cure of meat; I want to explore and elaborate on the science behind the traditional art forms of curing and aging in cannabis. (Due to the complexity of the preparation of cannabis, only speculations on the curing and aging methods of smoked cannabis will be elaborated on in the following essay.)
The art-science of curing and aging cannabis is a fascinating study, for, the metabolic constituents involved are quite unlike others that humans prepare in any such way, much less afterward administer. It turns out, somewhat unsurprisingly, that there are many layers involved in conceptualizing the differences between the curing and aging of cannabis, whether flower, hashish or concentrate. Deceptively, it can be seemingly easy to fathom the aging of compounds. After all, matter which has been exposed to time, temperature, and air could be aged, cured, or degraded, all by definition. An aging cultivar is only a few degrees from becoming volatile, a cured cultivar is really partially degraded, if not just by the measure of monoterpenoids. So, how to discern the difference between curing, aging, and degradation? Attention to detail.
Degradation: defined as, “to reduce the complexity of a chemical compound” can occur in a multitude of ways. Degradation, the circumstantial opposite of preservation, is a process where the components of a substance over time, especially but not necessarily in the presence of heat, air, and humidity, will break down, convert, oxidize, nucleate and/or polymerize under random, uncontrolled conditions. Degradation is a byproduct of many different reactions. Fermentation, for example, is the partial degradation of sugars or other organic ‘fuel’ without the presence of oxygen. Anaerobic respiration in yeast is also called fermentation. Oxidation often occurs in the presence of oxygen but does not need oxygen to occur, and is considered degradation by the loss of electrons from one substance, and oppositely reduction is degradation (or transformation) of the original compound by the gain of electrons to another substance. Oxidation and reduction often occur simultaneously and so have acquired a mutual term ‘redox.’
Degradation cannot mean negative consequences always, nor positive results. As many reactions can take place between hundreds of assortments of chemicals, each product is a new chemical variation which can interact with the substance uniquely. It is the responsibility of the cultivator and the post-processor to control the variables for the best possible outcome.
Curing: is the act of preserving secondary metabolites (such as aromatic volatiles) and controlling accompanying content for a more comfortable smoke. Yes, it has technically aged, however not in the same manner as other matter which humans have matured over time, of which wine and cider are readily applicable examples. Curing is an interactive dynamic state between secondary metabolites and accompanying constituents. Meaning that a cure can only be accomplished when secondary metabolites are associated with an ‘escort.’ In flower material the plant and trichomes are cured together; here the term cure applies to the amount of water preserved within the bud and the finding of a dynamic and acceptable equilibrium of associated components. During post-processing of cannabis, a solvent can be removed from secondary metabolites using temperature and the absence of air. Curing is seen in ice-water extraction also, where trichome heads are separated from water using temperature and air. Thus, the curing of cannabis, whether flower or extract, is a preservation technique aimed at the retention and balance of desirable constituents, and removal or balancing of undesirable constituents.
Aging: is a traditional preservation process where synergized components interact with one another in a solution. When produced correctly, an aged cultivar can provide a more thoroughly rounded experience for the consumer. Within time and variable environmental constraints, the substance generates tertiary chemicals from within, such as flavors and smells, requiring an environment where humidity, temperature, and UV are all controlled. Although degradation can occur during this process, cultivators attempt to prevent it as much as possible, except in cases where the degraded artifacts contribute positive aromatic qualities or desirable effects (as sometimes is the case in CBN, (an oxidation artifact of THC, is the product of decarboxylation from the acid precursor THCa) which synergizes with the effects of other cannabinoids. Historically, many parts of the world have implemented traditions around aging hashish, probably best documented by Frenchy Cannoli.
In an aged variety, some molecular constituents may change altogether, forming what is chemically known as an ‘artifact’. An artifact is a chemical that is not ordinarily present in a given substance, but the result of one or more of many processes, including; cytological processing, crystal formation, oxidation. Artifacts can be an indication of aging but do not alone define aging because artifacts are merely converts; they are the result of a chemical reaction. Many researchers have noted the presence of chemical artifacts likely introduced by thermally induced hydrolytic reactions. As the artifacts are chemically distinct from their precursors, they can smell, taste, and act differently.
As both the raisin and the wine come from a grape, so too can the cannabis flower be dried, separated, extracted and preserved to obtain distinct desired effects. It seems it would be most useful to breakdown the differences between preservation and possible curing or aging of cannabis flower and cannabis extract separately; thus, such information follows.
Flower
If research is conducted from the true beginning, then the living plant should be the first factor to consider in the curing or aging of cannabis.
Live cannabis flower can be harvested to three distinct advantages depending on the maturation and pigmentation of glandular trichome heads, described as follows.
1. Once the plants begin to near peak potency, which is approximately two weeks from an on-time harvest date, very few if any trichome heads will have ambered, but many will have filled out almost to completion. Frenchy Cannoli describes this as an ‘unripened’ trichome head, defined by not having fully formed an abscission layer between the trichome head and the disk cells beneath. Harvesting at this time frame preserves the adolescent, youthful, fresh aroma of the plant, and for extracts will assure that the color will be closer to a light blonde transparency. This process is similar to the picking of small rose buds for drying or extraction of ‘rose otto’ and other young oils. This method is a blatant waste in yield potential but could offer potentially distinct benefits, synergistically or not, as research has not yet proven otherwise.
2. The ‘on-time’ harvest is indicated by the full ‘pearling’ of the trichome head, with relatively few amber trichome heads (unless a purple variety: on which the trichome heads on pigmented pistils will tend to pigment somewhere between pink-purple). As components within the trichome head interact with one another, they facilitate changes which develop the aromatic and effective profile of the secondary metabolic constituents. For most growers, this is the ideal stage of harvest. This stage is best defined by the abscission layer which forms above the disk cells but below the stipe cells of the trichome head.
3. Finally, there is the late harvest, where plants are left to ‘ripen’ or finish slightly past their prime. Many growers utilize this strategy in hopes of obtaining a higher overall yield, but the little research done thus far indicates that only THC concentration increases in early plant senescence, where most other secondary metabolites seem to begin to degrade after the abscission is formed. At this stage some trichome cuticular membranes may ‘rupture’, degradation of trichome heads has begun, and oxidation of components within will have commenced. This is the first layer of an aged and artifact containing cannabis cultivar. A typical example of this concept would be an overly ripe fruit, bursting at the seams with juiciness.
Fresh Frozen
Upon harvesting the cultivar, the cultivator determines whether the cultivar will be frozen (for separation of live resin) or moved to a drying/curing phase. Fresh frozen is a preservation technique. When the bud is chopped and immediately frozen, it preserves the cuticular membrane of the trichome, along with the ingredients within. This is perhaps similar to fresh hops extractions for beer and removal of mycological secondary metabolites involving fresh mushroom and ice mentioned by Paul Stamets.
Dried Vs. Cured Flower
The aging of the flower appears unlikely to produce a positive dynamic between plant matter and secondary metabolites over extensive periods, most likely resulting in degradation of crucial components. Aside from freezing the buds, there is no other option than to dry or cure the cannabis flower. If the bud is not at least dried, it will be subject to sure contamination and spoilage, such as botrytis, due to the presence of moisture. There is a difference between drying and curing cannabis plants: To dry and to cure cannabis results in the extraction of moisture and volatiles from the nug: but over different time periods and environments.
Drying cannabis usually involves a very low air humidity and moderate temperature setting, but is more easily defined by the rapidity of the drying, whether hung by single stem V-cuts or multiple-stem V-cuts. The humidity needs to be sensitive to fungus prevention and the temperature sensitive to the retention of plant volatiles. If the buds dry too fast, they risk losing all distinctive aromatic qualities. Although the loss of monoterpenes during drying is inevitable, it is vital to retain the fragrance of cannabis as it facilitates a modulatory experience for the consumer and honors the cultivar.
A proper cure is defined by a minimal transformation of secondary metabolic components and mostly the loss of a large percentage of monoterpenoids and water, to cure means to attempt to partially preserve the life of the bud. The process of curing is only slightly different from merely drying. Curing a plant involves drying a plant with rigorous discipline and attention to detail over an extended time period. In this procedure, the plant is partially dried, then placed in containers for the duration of the process. Containers, half full or less, need to be opened with a cadent frequency or else will be subjected to fungal contamination. If opened too frequently then the buds will lose the unique characteristics of its smell and flavor profile. Hypothetically, because the secondary metabolic constituents within the trichome heads on the plant are all active constituents (subject to change by interaction with one another and with temperature and air), over time the constituents can settle into a sort of dynamic neutrality. When the cultivator finds that dynamic neutral has been reached, they may then choose whether they want to isolate the resinoid compounds from the plant material or sell the flowers as they are.
Dr. Allison Justice has done some incredible work around the curing of cannabis, who mentions not only delaying the death or ripening of the buds and their affiliated secondary metabolic constituents, but she also co-discovered the homogenization of moisture content, which may be a result of ‘burping’, during the curing process. She found that over time, the large buds which would normally have the most internally retained moisture (she notes that nugs dry from the outside in) instead had equal amounts of moisture to smaller buds as a result of the curing process. She also mentions an observed ‘exchange of gases’ during the burping stage, although she was unable to test for this exchange at the time of research.
Resinoid Compounds
Resin is a combination of waxes (primary metabolites) and essential oils (secondary metabolites). Secondary metabolites are are an extension of life in all living species. Trichome heads are unique because they contain a complex assortment of secondary metabolites generated by the plant. In fact, trichomes contain more secondary metabolites than any other part of the plant. The trichome is the apple of cannabis, the heart of sensimilla. The trichome head is where the essence of marijuana is contained, therefore extracting the trichome head is to express the essence, and part of the will of the plant.
The separation of secondary metabolic compounds from the remainder of cannabis substance can execute in many ways, where they become quite like essential oils in nature. Any number of methods can extract cannabis, and two distinct subsets of extract have emerged: 1. The extract which is composed of the entirety of the trichome head, and 2. the extract which only contains the secretory product from the above portion of the trichome head. Therefore, theoretically, the two styles of extract would require slightly distinct aging environments.
Primary and Secondary Metabolite Containing Substances
Usually, when wine, cider, and other substances are aged, it is for flavor/ experience enhancement.
A cannabis extract which contains the auxiliary and upper portion of the trichome head, (including sieved or ice-water extracted hashish and certain CO2 extracts) will inevitably include primary metabolite parts. When wine ages, acids interact with sugars. It is arguable that perhaps similarly, an undisturbed trichome head contains acids (phytocannabinoids), phenolic compounds, and terpenoids, which all maintain a corrosive nature against the constituents containing them. The latter constituents just referred to are called primary metabolites. Primary metabolites in the trichome head contain a cytoplasm, which includes all membranes except the cell wall, and portions of cytosol, also known as the cytoplasmic matrix. Cytosol is a highly complex organelle suspension solution made of a lot of water, and some sugars, RNA, proteins, messenger molecules, and is where many life processes happen including enzymatic activity, which plays a significant role in winemaking and aging. Due to these primary metabolites and possible build up of moisture, in the aging of hashish, it is imperative to occasionally open the container with the aging material to prevent mold/mildew. Instead, why couldn’t wine bottling practices be tried, where the cork serves as a moisture mitigator between the substance within and the external environment, with an emphasis on humidity. Perhaps also, in certain conditions, primary constituents can help to preserve secondary metabolites in the afterlife, similarly to in life. Without knowing precisely what the trichome head constitutes it will be difficult even to speculate the influence that any given metabolite might have on the solution in any number of environments.
Secondary Metabolite Containing Substances
In cannabis, there are now popularized super-potent extracts (documented thoroughly in Ed Rosenthal and Greg Zeman’s ‘Beyond Buds: Next Generation’, which contain few if any primary metabolites (Such as hydrocarbon extract or some forms of rosin). These extracts are much like essential oils in their chemistry, From ‘The Chemistry of Essential Oils’ by David Williams, comes a remarkable excerpt on the dramatic and dynamic expressiveness of an assortment of naturally derived synergistic components which make up a given substance.
“All essential oils are prone to deterioration simply by aging and by exposure to environments which cause chemical changes to their constituents to take place. The same is true of perfumes and perfumed products. If a freshly produced and dried essential oil were to be confined in a container of high-quality glass under a headspace of nitrogen or other inert gas, and protected from light, then the only chemical changes that could occur to the oil would be those caused by reactions between constituents. The lower the storage temperature, the more slowly would these reactions proceed; but proceed they would, over successive years, until eventually, no further perceptible change would occur. Among possible reactions would be those between aldehydes and alcohols to form acetals, between traces of organic acids and alcohols and between alcohols and esters (alcoholysis). Because of all of these reactions and others likely to occur are reversible, the final molecular state of the oil would be very far from one of complete inactivity, but one of dynamic equilibrium, or balance, in which the rate of each of the forward reactions would be equal to the rate of the reverse reaction. How fascinating it would be to open a sample of an essential oil stored for a hundred years under such conditions, for analysis in comparison with a fresh sample of the same oil produced under the same conditions.”
The aging of plant constituents is much like the aging of humans; the more careful the process, the more likely the process will retain significant and beautiful characteristics. There does seem to be an acceptable level of oxidation, nucleation, and polymerization in an aged or cured cannabis cultivar, CBN is an example of a degradation material that has a symbiotic relationship with the collective content. However, the color of CBN is of richer amber-red, which contributes to the appearance of the extract, a trait that is sometimes considered undesirable to cannabis critics, although the ambering of aged wines is considered desirable. Aging is graceful degradation, provided the right circumstances.
It is a great challenge to document the minute qualitative differences between the curing and aging of cannabis constituents. These processes, for now, remain more of an art than they are a science, perhaps leaving beauty to the eye of the beholder (or the smoker in this case). The fascinating expressions of these phyto-potions are infinitely unique and transformative. Many cannabis aficionados age their hashish, and many who cure; but there are very few researchers looking into the chemistry behind the degradation of these components, leaving the subject shrouded in mystery and speculation for the time being.
