A recurring question is:
"How do I know when to call the extraction process done, and take the extraction to the 'Finish and Filter Stage' ?
Many of us have just used a month marker system to answer the question for us: For example when extracting a light pure leaf a common time frame is 6 months, for a cigar a common time frame is 1 year, and for certain dark fired and heavy cased products from commercial blending houses a 3 month time frame seems reasonable. But, is that really the best way to determine time in the jar? For example there are glaring exceptions to these rules of thumb. An example is the pure leaf blends from Vincent Manil. His excellent blend Tabac Manil: La Brumeuse will extract to a very usable flavor profile density in as little as 2 months. So as with most 'Rules of Thumb' the success rate of applying the rule is far short of perfect.
I now use what I call the 'Skim Test' to get a grip on the question of when to call the process done.
The test was designed to be simple: form follows the required functions.
The form must follow these several target functions:
1.) It must be easy and fast to perform
2.) It must use the minimal amount of product under test
3.) It must be highly repeatable and reproducible with minimum error factor between tests.
4.) It must be able to applied to a wide range of flavor profiles.
5.) It should be able to accommodate various extraction media, i.e. Ethyl Alcohol, Propylene Glycol, etc.
What I came up with is: Using a calibrated 3ml plastic pipette, Skim 2 ml off the top. If done carefully you can extract mostly pure liquid that is free of solid tobacco pieces. This sample is placed in a 4ml straight sided clear glass screw top bottle. To that is added 2 ml of 100% Vegetable Glycerine. This creates a 50%VG/50% Extraction Solvent mixture and is handled like an old fashioned 'shake and vape'. The sample is used to saturate the cotton on a small atty suitable for Single Flavor A/B testing. The wattage and the coil must be held consistent over all your testing. Do Not change the atty between tests, in fact if you have a small MTL atty that you can reserve just for this type of testing that is all the better. This consistency of atty and simple 50/50 ratio allows you to learn, over time, and many tests, how the profiles behave. Your brain will become a casual but none the less surprisingly accurate appraisal test instrument of the progress of various extraction types.
I do not use any added Nic, and this is somewhat of a negative to the testing protocol as Nic can and does effect flavor profiles. But If you keep in mind the factors that added Nic would create you can still use the test to get very meaningful indications of the progression of the extraction process. And that is what we want from the testing. We are not looking for using this test as a way to understand the subtitles of the finished profile, we are just trying to answer the question that resolves, in simplest terms, 'does it need more extraction time in the jar?'
So this protocol it is fast and easy, it is a no brainer. You don't have to think, just grab equal amounts of the subject under test and your bottle of Pure VG. Could not be simpler. Also, there is no chance to make a mix mis calculation with some complex formula and screw up the result. Second reason it is a standard (for me at least) and therefore over the long haul and many such skim tests using the 50/50 certain information will begin to appear. Of course any test series has the value to accumulate information collected over time, but only if the variables are held identical. In this case the 50/50 and the atty is always the same, so the experimental 'baseline' criteria is satisfied.
Pipettes:
3ml Disposable Plastic Transfer Pipettes, Calibrated Dropper
https://amazon.com/dp/B07F3ZN56V/ref=cm ... WMK2WV8B8A
Sample Bottles:
144-Pack 1 Dram 4 ml Clear Glass Vials with Coned Caps
https://www.amazon.com/dp/B06XD6M9ST/re ... UTF8&psc=1
My Recommended SFT atty (your choice on this may vary, just keep it the same for all testing)
Vandy Vape 18 mm - BERSERKER MTL RDA
http://www.vandyvape.com/atomizer/rda/b ... r-mtl-rda/
50/50 Rapid Skim Testing