Hi I'm Josh ...
Unfortunately after trying to post this several times a few weeks ago whilst my internet was playing up I've forgotten the acute details of what I wanted to post, but I'll give you the best overview I can from memory.
The phenolic smell/flavour you can sometimes get from vanilla can be caused by a few things, It could either be the beans were not cured properly or that they were not stored properly.
It's a bad idea to keep vanilla beans in air tight containers as this can cause them to smell phenolic after some time. It's best to store them wrapped in some kind of parchment in a cool dry place.
I've found that some people don't realise that there are many diferant types of vanilla all with quite remarkably differing unique characteristics. Eg. Beans from India and some other places (Indonesia being another one I believe) can have a very tobacco like smell to them and not really smell much like what one would "expect" vanilla to smell like, but taste amazing. There's so many "strains" of vanilla and only one of them is the one we associate with the mainstream vanilla scent. They all smell and taste like vanilla to some extent, but a lot have quite strong odours of other stuff. Some smell of prunes for example!
If you are having issues with your vanilla smelling, tasting not how you want or if it's phenolic, then it may well just be that batch of vanilla, the supplier/grower not curing it properly, poor storage condition or simply a variety of vanilla that isn't to your preference. I would suggest trying out diferant beans from diferant countries and suppliers and hopefully you'll find something that fits your brew a lot better and doesn't give it a phenolic taste.
Madagascar Bourbon Vanilla Beans are the most popular and sought after vanilla variety. The flavor is rich, dark and creamy with an overwhelming sweet, buttery aroma. These are well suited for many baking recipes, drinks and desserts.
I know this is slightly off the forums topic, but I'd not long finished making some luscious vanilla ice cream when I decided to make this post, as I was worried that my beans were off as they smelled of coffee/tobacco and really nothing like any vanilla I had smelled before. I thought they had gone off, but after doing a lot of research it was just that particular strain of vanilla.
I'm not sure on the forum rules, so I'll not link to any sites selling vanilla, but I'll copy paste some quotes from a few places that gives some more in depth information about what I've been talking about.
Vanilla beans should be stored in a closed, but not air-tight, container in a cool, dry, relatively dark place. Do not store vanilla beans in the refrigerator or freezer! (The cold will dry them out and may promote a particular type of vanilla mold.) The important thing is that the temperature be relatively constant and that air circulate a bit. We also do not recommend vacuum-packing, as that can result in the beans' getting somewhat phenolic, leading to a highly unpleasant, acrid smell.
The "best practice" is to store your beans wrapped in wax paper, and kept in your food pantry in a closed, but unsealed, cardboard box.
The tobacco smell: Some, but not all, Indonesian vanilla beans are cured using a heat source by burning wood. This tends to leave some of the beans with a smokey or hickory-like smell (we sun cure our Indonesian pods to avoid this). If the pods were simply not cured correctly then they may put off what we call in the industry, a phenolic smell. Poorly cured pods will also tend to mold more easily....which seems to be the case with your stash.
Now for the yellow and white spots: If you touch the pod with your finger and and the heat of your finger causes the spots to melt or disappear then what you are seeing is actually the vanallin in the pod crystalizing on the surface of the pod. If this is not what you are experiencing then it is mold. If it is not too far advanced you can "clean" the pods with some vanilla extract which is 35% alcohol or wipe them with some vodka. The yellow mold will grow on the body of the pod and is quite persistent and you might have to throw the pods away. If it is white mold then it is usually growing on the tips of the pod and is easily killed by wiping as described above.
Dried out: If you solve the mold problem and the pods are usable but dry then we have a solution to that as well. A nice vanilla pod is easy to wrap around your finger. They should be at about 25% moisture content. If they are dry you can actually rehydrate them by placing them in a zip lock bag with about a tablespoon or two of water and let them sit for a couple of days.
Hope this helps. Enjoy!
Here's what I hope is an amusing/interesting story about vanilla. Back when I was doing computer dating (12+ years ago, I guess), I met a guy who worked at a local (HUGE) flavorings company. This guy was full of stories about why vanilla had gotten so expensive and why it wasn't any good right then. Tropical storms had decimated the orchid crops so companies like McCormick had to blend lesser vanillas just to get stuff on the shelves. The flavorings company had over 100 different vanillas, many that were specific to different food manufacturers (like Breyer's, Oreos, etc). When he and I met face to face, he handed me a box full of small brown bottles...ALL DIFFERENT VANILLAS in varying strengths! Each one had a distinctive fragrance and taste. Too bad the guy was a jerk, that stuff was amazing!
I hoped this little collection of information will save some people fair bit of time hunting about the internet trying to work out why their beans smell/taste diferant to what they had expected.
Enjoy your vanilla!
P.S. if anyone wants a mean recipe for vanilla ice cream let me know, there's no reason you couldn't add a bit of home brewed bourbon whisky to it when you make it either ... just to keep the post on topic!