DECARB
Of course the old tried and true is a baking sheet or foil in an oven and stinking up the house and neighborhood. I did that a year or so ago, had some nice brownies before the Roger Waters concert and enjoyed a nice body buzz. But the smell!!! So I searched and finally settled on two options. One was vacuum sealed bags in a hot water bath. The other was Mason jars.
Being an old gardener I have gear for canning tomatoes primarily. I thought (mistakenly as it turns out) that I could just do as I would with tomatoes. Fill your jars, seal pretty tight but not insanely so, lower in your jars and cover for about 45 minutes. With tomatoes you have fruit and liquid so the jars are fairly hefty. With cannabis the jars are nearly all air. I usually determine the water bath volume by using jars filled with water, lowered in, and then water added to be ½†above the jar. When they get boiling they naturally expel gasses and seal when they cool. With the cannabis the sealed jars just started to float all over. So I resorted to the
other Mason jar method. Decarb in the oven.
I put a baking sheet on the lower rack as a precaution for breakage. I preheat the oven to ~ 235F with my selection of empty jars on the upper rack. This reduces stress on the glass. When I was set with product and the oven was ready I pulled out a jar at a time and loaded with the T or the C as I was doing both and kept the two types apart for identification. Rings and lids were on fairly tight but didn’t want an explosion. I hoped that a slightly lower temp would save terps and by doing it a bit longer would compensate for a lower temp. When the jars deemed as thc were done I left the cbd jars in another 30 minutes since they would “usually†be decarbed in a hotter environment.
The water bath didn’t go to waste as I vacuum sealed another pile of weed and dropped it in the water bath for about 90 minutes. (Had to weight it down.) I reckoned that I was at an even lower temp than we’ve been using for years so longer time boiling was warranted.
Both systems worked very well. The jars had very little smell and the bag in water had none at all. Although the bag did seal in any vapors and made the product kind of wet. (Be certain there are no stems or sharp edges to pierce the bag.) Since then I’ve opened the bag and the moistness is minimal and the product seems to be cured equally as well as the jars. Any dampness left very quickly.
I have no science or measurements to share but I can say with full conviction that these two methods are superior to the foil sheets. No exposure to hot and dry oven air as well as trapping in the vast majority of smells. If you have the equipment for either method I’d suggest giving it a try versus a baking sheet.
The jar method is the winner for me right now since it eliminates the vacuum sealing and water boiling. I think if I get a big batch going it would be the bags, though.
In searching for information on decarb times and temps I realized the old 300F for 30 minutes was still out there. Fortunately as research is being done on more aspects of cannabis the decarb processes are becoming a bit more clear. For THCa to convert to THC requires
about 240F for about 45 minutes. For CBDa to convert to CBD requires
about 260F for about 60 minutes. So I used lower temps than these and similar times or slightly longer. Decarb requires both time and temp so a little mental math is in order. Like most things cannabis there is no exact answer to most anything.
Posts I stole from or learned from:
https://forum.growweedeasy.com/forum/growing-community/355183-decarboxylation-not-just-for-edibles
https://forum.growweedeasy.com/forum/growing-community/351649-decarboxylation