Preparing edibles is like learning to ride a bike—once you've got it down, there's no going back. There are a few very common mistakes that can easily be avoided and will ensure that your canna-goodies turn out brain-meltingly good. The most wide spread problem is people do not "decarboxylate" their medication before preparing an ingestible formulation, such as edibles or an infused beverage.
What is Decarboxylation?
Far and away, the mistake you'll hear of people most often making is NOT DECARBOXYLATING their starting material, be it flower or hash. This step is crucial to unlocking the actual potency your starting material contains. Let's go over the science of it briefly.
When THC, the main active ingredient in Cannabis, is found in cured Flower or hashish, it is usually in its predecarbed form: THC-A. As the name implies, decarboxylation removes a carboxyl group from the THC-A molecule. This is a necessary step for the THC to be absorbed in your stomach and metabolized. Most starting material's THC is going to be at least ~90% THC-A, and plain ol' THC-A cannot be metabolized and absorbed by your gut. Some of the THC in the cured Flower, or hashish, or whatever starting material you're working with will already have its Carboxyl group cleaved off- this is because decarboxylation occurs as a function of both heat and time. Simply by sitting at normal temperatures for a long time, the product will slightly decarboxylate. So, some of the molecules will undergo the chemical reaction, and be thus the psychoactive THC and not the non-psychoactive, anti-inflammatory THC-A.
However, there's still loads of THC that could be decarboxylated before the cooking process, and that should be, if one wishes to get the most out of their material. During the actual cooking process itself, some will be decarboxylated, but again, not nearly the amount you want. A lot will be wasted without this step being performed pre-cooking. This should explain why if you or a friend have made edibles in the past, one might think it was done "successfully" without the decarboxylation step. This is a very, very common mistake. SOME of the THC was prepared properly as a side effect of the cooking, and even more far-fetchedly, the curing process.
So, you want to decarboxylate your material before you ever cook with it. That should be clear thus far. Bump up your THC-A converted to THC percentages from 15-20 percent to 80-90 percent! But how?
How do I decarb my material?
Whether you are working with flower or with hash (dry hash or hash oil), you'll want to decarb in an oven, most likely. As stated above, decarboxylation occurs as a function of both heat and time. So, the more time it's at a certain heat, the less heat needed, and the higher the temperature used, the less time is needed to decarboxylate fully. Heat ALSO will break down THC (not THC-A directly) further into CBN, or Cannabinol. This cannabinoid is one of the few psychoactive, major cannabinoids in cannabis, and has a sedative effect. Feel free to do more research on CBN, because depending on your medicinal needs, a deeper decarboxylation, which would convert more THC-A ->THC ->CBN instead of mainly just THC-A ->THC, might be preferable. This would certainly be the case if you need your edibles to induce the sleepiest kind of high possible, the most "Indica-like," or most having the qualia of a straight Indica strain. However, for most people, THC is what we're after, and the CBN augments and plays an important role in the effect we're looking for, but is not the primary player.
There are charts that give you a curve you can follow that shows you combinations of temperature and duration you can choose from. Lower heat, and longer duration, will lead to a more even, thorough decarboxylation. I will leave one such chart here, although they can be found all over. Here is one from Skunk Pharmaceuticals:
Now, although the marked examples on the graph are seven minutes at ~300 degrees Fahrenheit, or 20 and 27 mintues at ~250 degrees, other research has shown that a decarb duration of closer to a full hour will yield the best results with as little residual THC-A as possible. So, I would personally recommend the 223 degree curve on that graph, which shows at 51 minutes the process hitting an optimal point. We can round off these numbers for an easier to remember process- 225 degrees Fahrenheit for 1 hour.
I mentioned before that we will be using an oven for this. There are now products for decarbing your material that claim to be much more effective than a home oven, and claim that using a home oven will destroy up to a third of your precious active ingredients. It's difficult to tell how much of this is a marketing ploy, but check out the Nova aka Lift by ArdenCannabis.com sometime.
However, for all intents and purposes, an oven is truly fine to use. If you are working with flower, break it up into small chunks if it is not already in small nuggets and spread your material out on top of a piece of parchment paper in a large cookie sheet. Use the middle rack of your oven, and like stated above throw it in there at 225 degrees for 1 hour. Some people like to cover the cookie sheet with aluminum foil to "trap in" the cannabinoids, but this is not necessary. If you are working with hashish, do the same, spreading it thinly across the parchment paper. However, with hashish, one must be careful it does not get to thin in the oven and spill off the parchment onto the cookie sheet- thus, make sure the parchment paper comes up and over the edges of the cookie sheet so you have a nice large recessed area to put the material in, and leave a small margin for it to spread into.
After taking the cookie sheet out of the oven (one hour later), flower should be starting to just lose it's bright green color and turn to a bit more neutral of a color- don't freak out! This is good! In fact, smoking decarboxylated buds is actually a bit more potent than buds that have not been decarboxylated. Save a little bit to spark up and you'll know what I mean! Decarbed flower right out of the oven should also crush to a fine powder between your fingers. Now, decarbed hashish or hash oil will usually maintain somewhat it's original form. However, it's now three to four times as potent as an edible starting material.
But the oven will stink up the house!
If you are someone who needs to avoid the smell of Cannabis in your home, have no fear. Sous vide is here! This nifty trick can help you decarb your cannabis without producing any pungent odors. Simply put all your flower (this only really works with Flower or Kief) in a heat resistant plastic bag meant for Sous Vide cooking. Then simply submerge it in simmering water (the water will keep everything from getting too hot, so don't worry about the temps), for again, one full hour. And voila! Be careful not to use any old plastic ziplock!
At this point, you wouldn't even need to cook the product into fat to get an effect. Eating the appropriate amount of decarbed flower would be gross, but it would have strong effects. However, through a process called "lipo-encapsulation," the cannabinoids can be transported through your system much more effectively, and this is achieved by cooking the decarbed product into a fat, such as butter or coconut oil. You could also use your decarbed product to make a delicious infused beverage! It's up to you! But know that now, you're not wasting any of the actives in your expensive starting material by skipping this crucial step in the edible preparation process.