|MadSci Network: Biochemistry
Bad news: There's no common way to make perfumes. Good news: Most perfumes are similar in how they are prepared. Now that I've summarized the answer in two sentences, let's discuss what they mean. Perfumes are basically very complex mixtures of chemicals, designed to have pleasing scents, as well as to be stable over time and relatively nontoxic. Depending on the scent you want, you'll need to put different mixtures of chemicals into the pot. Perfume design is traditionally not a very scientific process. Basically, people come up with an idea for a smell, and then they mix chemicals together which, from their own experience, might produce that smell. When they come up with a winning mixture that doesn't produce brain damage in rats (or other negative side effects in lab animals), they market it and sell for eighty bucks an ounce. Perfumes basically are three-part mixtures of chemicals. The first part, the fragrance, is the one that we usually think about. These are generally esters, aldehydes, or aromatic organic compounds that occur naturally in flowers, fruits, or other things that smell nice. The second part, the solvent, is used to dissolve all the fragrance, and evaporate slowly so that the perfume's scent is given off over a period of time, and not all at once. These are usually common solvents such as acetone or ethanol. The third part consists of stabilizers and fillers, which are used to bulk up the fragrance and make sure that it doesn't degrade over time. Depending on the compounds being used, these will vary, although in some cases the solvent also acts as a preservative and filler. So, how can you make your own perfume? Well, I'm not going to tell you how to make fragrant chemicals. Doing organic chemistry is dangerous stuff, especially to try at home or if you're not all that experienced with it. There are, however, some ways that you can make perfumes without venturing into the lab. Aromatherapists believe that "essential oils" can restore good health - I don't believe this, but I do know that the oils often smell pretty good. Find a mix of these you like. Also, you might want to try using nearly pure ethanol (available at the drug store) to extract flower scents: Soak mashed flower petals in ethanol and see if you can't make your own essential oils. Will it work? I'm not sure - however, flower petals are cheap, as is ethanol. (A word of warning - although the ethanol you buy at the chemist's is very nearly pure, don't drink it! It contains stuff that will kill you!) There are a number of readily-available perfume-making kits out there on the market. I seem to recall that Edmund-Scientific sells one, and I know that if you let your mouse do the walking, you can probably find others on the internet. One website that's good at listing perfume-related data is this: http://www.supernet.net/~jackibar/chemicals.html This site is run by a bunch of people who think that the chemicals in perfumes can kill you, and that perfumes are poorly tested on people. Don't be alarmed when you read this stuff: Although SOME of the chemicals they list are dangerous, very few are dangerous in the quantities found in perfumes. The "data" they present to back their findings are found on Material Safety Data Sheets produced by the US government, and these sheets are comical in the hazards they list. (Sterilized, washed sea sand, used in chromatography, is listed as being an inhalation hazard, as if you didn't know not to breathe sand already). Take this stuff with a grain of salt. One chemical in particular which is listed to be a hazard is limonene - if you're afraid of limonene, then don't eat citrus fruit, because you can find it there. The same goes with many of these other chemicals. Still, some people are indeed susceptible to very trace quantities of chemicals in their environment - the site is correct when it states that these chemicals can produce terrible effects in a very limited number of people. I've known people with this condition, and their lives are very restricted by their allergies. However, for 99.99% of the people out there (and probably you, too), there is very little danger in any of these naturally-occuring chemicals.
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