I like to turn my 'popcorn buds' and shake into cannabutter for making caramels and chocolate truffles. A problem with confectionery is the high temperatures that one needs to bring the sugar to before it is at the correct stage for making candy. Typically, caramels will be brought to 245 degrees F, and if there is any plant material or even excess chlorophyll in the butter, it will have a scorched and very unpleasant flavor.
So this is a little tutorial on the process by which I make my washed cannabutter.
Step 1 is to grind up the herb. I just run it through a hand grinder but if you feel sassy, a $15 coffee grinder just for your pot is really trick. Next, I weigh it out and decide what I want my dosage to be. I like to dose butter at 2 grams per tablespoon. The butter should be of decent quality. It doesn't matter if it is salted, because we are going to 'wash' it later.
Next, take your butter and ground herb and put it in a wide-mouthed canning jar. Add enough water to fully wet the herb.
Put the jar with the butter, water, and cannabis in a large stockpot with enough hot water to reach up to the shoulders of the jar. Screw on the band but don't tighten it down- hot air and water vapor must be able to escape. Bring the water bath just to BARELY a simmer.
Periodically, remove the jar from the water bath, tighten the lid, and gently shake the contents to re-mix, as they tend to stratify. Loosen the band again before returning the jar to the water bath. Heat for about 2 hours, then pour into a second jar, through a potato ricer to strain, and squeeze out ALL the liquid.
Place this jar in the refrigerator until the two phases stratify and the butter sets into a solid mass. Poke a large hole through the butter and pour out all the water through a strainer to catch any butter pieces floating in the water. Re-fill with clean water and return to the hot water bath. HOT WATER ON COLD GLASS WILL CRACK THE GLASS! Bring the bath back to temperature gradually.
Now repeat the heating and shaking process. You will see that the water becomes cloudy. This is all contamination leaving the butter. Chlorophyll, plant matter, even excess fertilizer salts are washed away, leaving pure butter with the psychoactive compounds.
This is called a liquid-liquid extraction, and takes advantage of the different solubilities of polar (salts) vs nonpolar (hydrocarbons) compounds in polar (water) vs nonpolar (oil) solvents.
Repeat the chilling and separating process, re-fill with water, heat again. The third time, the water should remain quite clear, and when you pour it out, pour it through a permanent coffee filter (the metal kind) to remove any large particles still remaining. This time when you chill it, you will notice what a lovely pale green color it is, and also that it smells like sweet butter and hash, but not really like pot.
When you cook with washed butter, the cannabis flavors are very subdued, to the point where you may not even notice any at all. Nice stuff.
Here's a couple pics of different techniques and pieces of equipment- note that in some pics, the product I'm making is actually heavy cream, but the straining technique is the same.