canadiancannabis
New Member
The sludge is from plant matter being in your your oil. I had this happen last year when I didn't filler it enough before evaporating the alcohol off
Burning RSO: What causes the sludge that can appear and how to stop it
- Thread starter Bodywork38
- Start date
MimiEMU
420 Member
"My question is this: Why does sludge form? For instance, I left a batch too long in the rice cooker one time and it burnt. Why does this happen? IF the rice cooker can't exceed the 180F mark that ethanol burns at and when it switched to it's warm setting, which is lower than what is needed for decarb, why did it produce the burnt sludge?"
First, realize RSO is an unrefined crude oil. Alcohol extraction is known as a non-specific extraction - it takes any and all compounds it will dissolve. This means you get the non-polar lipids, semi-polar phospholipids and some polar compounds. You're cooking this all together and it will be a sludge. Typical RSO comes in around 40% Total Cannabinoids which means 60% of your oil is trash. Thats the reality. You'll have to do some refinements to dump the trash to make better oil. Thats a big part of the sludge you're seeing, and it's easy to burn at higher temps.
As far as the rice cooker temp, all these devices are engineered to pump X amount of BTUs into the cooking vessel. That much heat will be funneled into your oil or wasted on outter edges of the pan. If you have a couple ounces of oil it it, then that little amount of oil will absorb most of that heat. Oil has a huge capacity to hold heat. So little oil will get extremely hot. Lots of oil will be less hot.
I personally use an electric skillet for a double boiler heat source. Skillets have a thermostatic power cord that has a dial on it to dial in the amount of heat. But this # is relative to what I am heating. I can easily overheat a couple grams of oil, but an ounce (28.5 grams) will heat up less proportionately. My 12 inch skillet has a 1000watt power cord, so to reduce and decarb the oil, I set the dial at 200f and use a digital thermometer and see decarbing happen at 250f. Eventually as the C02 stops boiling out, the heat starts spiking and can hit 300f. Venting gasses take away heat, so when the venting stops, all those BTU end up in your oil which leads to spiking temps.
Unfortunately, rice cookers don't give you much control over the power and the auto-shutoffs are a nuiscance. Check out thrift shops, Goodwills, garage sales, estate sales. You can find skillets really cheap. I have 4 all under $10us. One cost me $0.75us at a church yard sale. The key is the thermostatic power cord. Look for those devices. Griddles, skilletes, fondue makers all use this tech.
Check out the grapic attached. This are the phases of boiling that happens when you boil out the alcohol, any water, then decarb. Alcohol starts in the 170s, goes up to 212f. Water boils out at 180 up to 225f. The remaining oils decarbs throughout, very slowly at low temps, but rapidly at 250f. This is technically the most accurate way to decarb because you're monitoring the decarbing in action - the generation of C02 bubbles. Once the bubble generation diminishes, you've reach an optimal decarbed state. As Carla Kay says, watch the bubbles! That's your indicator to know when to quit.
First, realize RSO is an unrefined crude oil. Alcohol extraction is known as a non-specific extraction - it takes any and all compounds it will dissolve. This means you get the non-polar lipids, semi-polar phospholipids and some polar compounds. You're cooking this all together and it will be a sludge. Typical RSO comes in around 40% Total Cannabinoids which means 60% of your oil is trash. Thats the reality. You'll have to do some refinements to dump the trash to make better oil. Thats a big part of the sludge you're seeing, and it's easy to burn at higher temps.
As far as the rice cooker temp, all these devices are engineered to pump X amount of BTUs into the cooking vessel. That much heat will be funneled into your oil or wasted on outter edges of the pan. If you have a couple ounces of oil it it, then that little amount of oil will absorb most of that heat. Oil has a huge capacity to hold heat. So little oil will get extremely hot. Lots of oil will be less hot.
I personally use an electric skillet for a double boiler heat source. Skillets have a thermostatic power cord that has a dial on it to dial in the amount of heat. But this # is relative to what I am heating. I can easily overheat a couple grams of oil, but an ounce (28.5 grams) will heat up less proportionately. My 12 inch skillet has a 1000watt power cord, so to reduce and decarb the oil, I set the dial at 200f and use a digital thermometer and see decarbing happen at 250f. Eventually as the C02 stops boiling out, the heat starts spiking and can hit 300f. Venting gasses take away heat, so when the venting stops, all those BTU end up in your oil which leads to spiking temps.
Unfortunately, rice cookers don't give you much control over the power and the auto-shutoffs are a nuiscance. Check out thrift shops, Goodwills, garage sales, estate sales. You can find skillets really cheap. I have 4 all under $10us. One cost me $0.75us at a church yard sale. The key is the thermostatic power cord. Look for those devices. Griddles, skilletes, fondue makers all use this tech.
Check out the grapic attached. This are the phases of boiling that happens when you boil out the alcohol, any water, then decarb. Alcohol starts in the 170s, goes up to 212f. Water boils out at 180 up to 225f. The remaining oils decarbs throughout, very slowly at low temps, but rapidly at 250f. This is technically the most accurate way to decarb because you're monitoring the decarbing in action - the generation of C02 bubbles. Once the bubble generation diminishes, you've reach an optimal decarbed state. As Carla Kay says, watch the bubbles! That's your indicator to know when to quit.
KBUENOS
Well-Known Member
I think that your decarb temperature is a little too high personally, I keep it between 230-240 personally, and I stay right with the product during the finishing process, decarbing on a diffuser or mug warmer just feels right lol. I hope that this will be helpful to you, you can look forward to keeping more of those terpenes also, I make mine in a jar after the distillation is complete and when the solvent is completely gone I finish it off in a sealed jar.
Thanks for sharing and allowing us to yak at youif you ever want to yak in the future I am here for it. Have an awesome day Gromie
MimiEMU
420 Member
Just like water boils at 212f, decarboxylation where C02 is shed most rapidly happens at around 250f. This will depend on your altititude.