Life of cologne.

I have read differing opinions on how long a cologne lasts after you open it. I have never found a cologne to have "gone bad" even five years after I first opened it, but this seems to be the understood "expiration date". Maybe this is only some of the mainstream colognes and not the higher end ones like Penhaligon and Creed? I'm curious to hear other's opinions and experiences in regards to this.

I realize that this has already been discussed to some degree here: http://www.badgerandblade.com/vb/showthread.php?t=7799&highlight=shelf+life but I'd still be interested to hear more.

I have heard of gents buying 20 year old bottles of Floris #89 and it still has punch.

I think it depends on the cologne. Some probably last longer than others. I have some old, seldom used colognes that once in a great while I check out - and they still smell like they should. My wife keeps her fragrences in the fridge.

Another question though, do colognes deccline slowly even before they are opened?

Colognes deteriorate faster when exposed to sunlight and heat. If stored properly they should last a long time.

The overriding Factor may be is how they are stored, on a windowsill they could be dead in 3 weeks, cool and dark? maybe decades.

I keep my fragrances in a leather box that is covered on my dresser.

Extra bottles that are not open are in the fridge.

YMMV

I would worry about refrigerating scents. For example, I know that you should never refrigerate olive oil because it will ruin some of the volatile compounds that carry the flavor of the oil. Wouldn't the same thing happen to some of the scent ingredients in a cologne, throwing the scent off-kilter?

I think with olive oil, you avoid refrigerating it because it can turn cloudy. In terms of flavour, volatiles in cold olive oil will be trapped, you wont semll or taste them so much. That's why crappy beer is served extra cold, and you can make rough wine palatable by chilling it severely. The cold isn't going to damage the oil- in fact it will retard oxidation and decomposition, but you'd do well to allow it to warm up before eating it, to have it at it's best, like a bottle of claret.

Fragrances won't go off, as such- too high alcohol content, and essential oils are in themselves highly antiseptic. But the greater the exposure to air, the more volatiles will evaporate and be lost, making the scent weaker. The aroma will change with exposure to sunlight and air, and the higher the temp, the faster this can take place.

Floris perfumes contain a chemical, I think a benzophenone, which prevents or reduces damage caused by light. It also happens to be easily demonstrated as a rapid cause of oestrogen imbalance in test animals- look up some papers if you have acces to any databases, it's scary. Perhaps brown glass bottles would be safer.
Beer with a really hoppy character can become "lightstruck" within moments on exposure to light, resulting in that delicious floral boquet of the Goldings starting to smell like cat wee. In beers made with isomerised hop extract this does not happen. In beers without (eg with real hops, good beer) they are bottled in brown glass to prevent such deterioration.
Perfumes were originally sold in such brown bottles- standard medicine bottles, and folks could decant it into smaller, attractive scent bottles, thus minimising contact with air (the large bottle was rarely opened) and light (brown glass)

Oxygen can react with essential oil components and change the scent. The change may be subtle, but you can expect a 20 year old bottle of perfume to be different at least. Antique bottles of perfume can smell lovely- but you aren't necessarily smelling what the perfumer intended. Over even 20 yrs though, changes should be subtle, if it was well stored- in fact, perfumes are usually aged, to allow the smells to "marry" together, and make a more coherent boquet.
As for modern synthetic scents, who knows? I've a suspicion the fruit fragrances might turn ugly after a few years- fruit flavoured tobaccos taste rotten when they get old. Good vanilla aromatics aren't so bad, and blends scented with EO's get excellent, much better with age, for example St Bruno (mainly scented with Bergamot) can be incredible at 50 years old, should you be so lucky as to get a tin that old.

I would guess that the order of damage would be:

1. Short-wave UV light - can break down aromatic molecules in EOs but may not get through the glass bottle.

2. Oxygen (posssibly CO2 as well) - may oxidize the EOs.

3. Moderate heat - slowly drives off top notes and possibly changes the chemistry of the EOs over a long time.

I almost always keep colognes in the original box in a cool place. I have some ~15 YO Dunhill Blend 30 that still smells good but probably not quite as sharp as when new. I dumped some ~10 YO Worth Pour Homme that went from light green to brown and lost most of its smell. Probably best to store colognes like wine - cool, dark place, don't reflux lots of air into the bottle. Sprays may be better that stoppers.

The first cologne I ever purchased was JPG about7 years ago. I've noticed in the last few months that it has lost a bit of it's punch. Two sprays would knock you out of the room when I first got it, now I do three full sprays and I can't notice the scent after a few hours. Good excuse to buy more!