I just got my Capella in today and am preparing some test vials of the Capella v2, TFA Vanilla Bean Gelato, and the old TFA Vanilla Custard. Actually, I made up the TFA samples a few days ago and gave them a night of low heat curing.
The TFA custard opened up and is WAY smoother than the TFA Gelato, which I suppose is to be expected from a diketone-rich mix compared to butyric acid solutions. The Gelato isn't bad, just not as rounded or buttery. I tested at 5 and 7.5% concentrations in a 0mg 50-50 mix and did not get the vomit scents people associate with butyric acid. That stuff happens at higher concentrations; at low percentages like this it's pretty much a light butter note.
Thing is, when I mixed up my Capella sample I sniff tested the Capella and the Gelato right out of the bottle and they're very similar. There are definite butyric acid notes coming off the Capella. These did calm down in the TFA Gelato after a few days and 8 hours of heat, so I'm not too too worried, but I don't think you can get a legendary smooth custard without diketones. I kinda expect the Capella V2 to mature out quite similarly to the Gelato, which is annoying since I paid a lot more and waited longer for the Capella to get here.
The interesting thing about butyric acid, according to Linda from TFA in an ECF thread I can't find right now, is that it's a diacetyl inhibitor. I found a reference to this in rat testing: http://www.ncbi.nlm.nih.gov/pubmed/18940962. I suppose mixing the old diketone custards with a little of the butyric acid custards would make a "safer" rich custard. "Butyric acid may modulate diacetyl toxicity by inhibiting its metabolism and/or altering its inhalation dosimetric patterns." The uptake inhibition was relatively small, so it's not like a magic bullet or anything.
I'll update once I get the Capella to open up, but I expect I'm going to be pissed off when I discover the Capella V2 is functionally identical to the TFA. TFA answered all my questions, sent me those samples for FREE when I asked about them in my previous order, and shipped really fast. Really nice company.
Yeah I've been wholly unimpressed with the new diketone free offerings I've tried.
Currently I'm experimenting with using them with diketone containing flavorings and I think there's potential for deliciousness there.
After a couple of hot baths and days I'm not impressed at all with the v2. I talked to a guy who was talking about mixing the v2-ish stuff with other flavors to restore the custard notes. Naturally, all the other flavors are alpha-diketone components; they just didn't realize it because they didn't say "Custard" in the flavor name.
Been messing with Capellas V2s for three weeks. Heat cures/plain old aging. 20 or thirty different recipes tried.
I'm liking French Vanilla V2 A LOT better than Custard V2. Mixes well and surprisingly strongly with fruits.
Pissed about Vanilla Custard V2. If I'd known VCV2 was going to suck so hard I would have just ordered the original, now I've got 3.5oz that I'm pretty sure I'm never going to use.
My final take is that if you want to bring a diketone free buttery/custardy background to some fruits FVV2 is solid. If you're looking to make a custard, look elsewhere than VCV2.
I haven't played with any other Capella flavors; I find their pricing prohibitive and don't like their weasel wording on ingredients. If I can find a deal (ha ha) on some VCV1 I might give it a shot to see what all the fuss is about.
I think there's some potential for the butyric acid compounds to be used as a minor component of the alpha-diketone flavorings to bring a little balance and roundness. However I think vaping diluted butyric acid flavors gives me a headache, so it would have to be a very small percentage.
Side note: VCV2 flavor test vial got even weirder tasting today, but the TFA Gelato did not. I think the VCV2 may be a clever marketing ploy to sell more original formula.