Speaking in
very general terms; nicotine (especially in freebase form... "regular" nicotine concentrate, to us DIYers), as it oxidizes, looses its potency.
I have only seen anecdotal home experiments reported in the forums (vs. controlled laboratory experiments) for the most part. But, the results
seem to indicate that the reduction is rather slow and minimal. in other words; it takes a lot of oxidation, over a long period of time, to have a significant impact on nicotine potency.
The greater impact of oxidation (at least; in
my mind);
seems to be a change/increase, to harshness/throat hit and taste (bringing out more of the nicotine's own unique flavor... which can vary source to source). But, again, evidence appears to be mostly anecdotal.
To
me, the real bottom line is; if one likes the results, from
any mixing process(es) one chooses to use, then that is the right choice for
that individual. Conversely, if one is not satisfied, considering alternatives is only prudent. I am
extremely reluctant to say, that there is only one "right" way, for all DIYers to mix.
And... since I seem to have stepped up onto my soapbox, yet again
... I will offer one more item as food for thought. Something else aeration can be responsible for. And, that is, flavor loss.
Flavors come come from all sorts of various molecules, and chemical compounds. Some of these are what chemistry defines as "volatile." Volatile simply means that these molecules easily evaporate at room temperature. As they evaporate, we loose any benefit they may add, to our perceived taste/flavor profile. When we excessively aerate a mix; we can be accelerating this evaporation, and therefore, flavor loss.
Now, having said that; not all flavor concentrates have the same amount of volatile flavor compounds. Some, like most dairies and some tobaccos, seem to have little to no volatiles to them, and seem to be impervious to flavor loss. Others, like many fruits and florals, have quite a few, and can quickly disappear almost completely.
As
my general rule of thumb, and completely unscientific; I try to use my nose as a guide. The more aromatic a concentrate is, the more likely it has a significant amount of volatiles in it. So, I try to aerate it less.
Aeration is not the only cause of flavor loss. Any extended exposure to air will also contribute. Too much airspace in a storage bottle. Highly permeable materials, like plastics (some more than others), and especially rubbers (like the squeeze bulbs, and seals, found on eye-dropper caps), can contribute to flavor loss.
Adding heat, increases/accelerates volatility, and can speed up flavor loss (especially in open containers).
Though again, I would temper this by saying; if it is working for you, don't worry about it. However, if you are getting unsatisfactory results, or feel like your are using way more flavoring than you think you should be needing...
then, look at your current mixing methods, and consider trying something else.
This all, is just my opinion; based mostly on my own personal experience. So,
please, experiment for yourself. And remember; "your mileage may vary."
.
