20 ms·

I was wondering the same. I would guess the dimension is high (maybe in the 10s or 100s?), and smells should be rarely 'similar', because I believe most smells

I was wondering the same. I would guess the dimension is high (maybe in the 10s or 100s?), and smells should be rarely 'similar', because I believe most smells can be traced to a single compound or family of compounds (with shared structure). For example, "fishy" smell seems to be associated with a singe molecule, Trimethylamine [1]. I got a single hit from a google search: "On the dimensionality of odor space" http://elifesciences.org/content/4/e07865 http://elifesciences.org/content/4/e07865

logfromblammo 11y ago
Match the smells to the molecule: farts methyl mercaptan (thiol + methyl) durian/onion ethyl mercaptan (thiol + ethyl) skunk butyl mercaptan (thiol + butyl) coffee furfuryl mercaptan (furan + 2-methanethiol) grapefruit grapefruit mercaptan (cyclohexene + 1-methyl + 4R-isopropyl-2-thiol) lilac alpha-terpineol (cyclohexene + 1-methyl + 4-isopropyl-2-ol) almond/cherry benzaldehyde (phenyl + formyl) anise anisaldehyde (phenyl + 1-formyl + 4-methoxy) cinnamon cinnamadehyde (phenyl + acrolein) tar cresol (phenyl + 1-hydroxy + (2 or 3 or 4)-methyl) smoke guaiacol (phenyl + 1-hydroxy + 2-methoxy) vanilla vanillin (phenyl + 1-hydroxy + 2-methoxy + 4-formyl) clove eugenol (phenyl + 1-hydroxy + 2-methoxy + 4-allyl) oregano carvacrol (phenyl + 1-hydroxy + 2-methyl + 5-isopropyl) thyme thymol (phenyl + 1-hydroxy + 2-isopropyl + 5-methyl) mint menthol (cyclohexanyl + 1R-hydroxy + 2S-isopropyl + 5R-methyl) caraway [S+]-carvone (1-cyclohex-2-enone + 2-methyl + 5S-isopropenyl) spearmint [R-]-carvone (1-cyclohex-2-enone + 2-methyl + 5R-isopropenyl) pine [S-]-limonene (cyclohexene + 1-methyl + 4S-isopropenyl) orange [R+]-limonene (cyclohexene + 1-methyl + 4R-isopropenyl) fish trimethylamine cabbage/ocean dimethyl sulfide butter diacetyl + acetoin vomit butyric acid pineapple methyl butyrate orange ethyl butyrate strawberry propyl butyrate, butyl butyrate pear/apricot pentyl butyrate glue methyl acetate pear ethyl acetate apple/banana butyl acetate, amyl acetate vinegar acetic acid goat cheese capric acid, caprylic acids popcorn 6-acetyl-1,2,3,4-tetrahydro-pyridine coconut gamma-nonalactone peach gamma-undecalactone garlic diallyl disulfide, diallyl trisulfide, diallyl tetrasulfide So I'd say that olfaction primitives probably number at least in the low hundreds. It seems as though just substituting a single functional group on an aromatic ring or changing the length of a carbon chain can affect human perception of the odor. Chirality usually matters. Orientation of the double bonds usually matters. Most frustratingly, concentration also matters. Indole smells like jasmine flowers at low concentrations and like poop at higher concentrations. It may well be that we don't have dedicated words for smells because the IUPAC chemical naming conventions make them unnecessary. Also, most people don't need them. Professional aromatists would probably just say the chemical name, or use the perfumery primitives like the plant essential oils or resins, ambergris, civet, castoreum, hyrax, musk, and beeswax. Esters are fruity. Linear terpenes are grassy or herby. Cyclic terpenes are woody or flowery. Substituted aromatics are flowery or herby. Amines are rotten or fishy. Thiols just plain stink. Wine snobs can probably just make up whatever words they want to describe their noses and bouquets, because their words don't really transmit meaning most of the time, anyway.

logfromblammo 11y ago

Match the smells to the molecule: farts methyl mercaptan (thiol + methyl) durian/onion ethyl mercaptan (thiol + ethyl) skunk butyl mercaptan (thiol + butyl) coffee furfuryl mercaptan (furan + 2-methanethiol) grapefruit grapefruit mercaptan (cyclohexene + 1-methyl + 4R-isopropyl-2-thiol) lilac alpha-terpineol (cyclohexene + 1-methyl + 4-isopropyl-2-ol) almond/cherry benzaldehyde (phenyl + formyl) anise anisaldehyde (phenyl + 1-formyl + 4-methoxy) cinnamon cinnamadehyde (phenyl + acrolein) tar cresol (phenyl + 1-hydroxy + (2 or 3 or 4)-methyl) smoke guaiacol (phenyl + 1-hydroxy + 2-methoxy) vanilla vanillin (phenyl + 1-hydroxy + 2-methoxy + 4-formyl) clove eugenol (phenyl + 1-hydroxy + 2-methoxy + 4-allyl) oregano carvacrol (phenyl + 1-hydroxy + 2-methyl + 5-isopropyl) thyme thymol (phenyl + 1-hydroxy + 2-isopropyl + 5-methyl) mint menthol (cyclohexanyl + 1R-hydroxy + 2S-isopropyl + 5R-methyl) caraway [S+]-carvone (1-cyclohex-2-enone + 2-methyl + 5S-isopropenyl) spearmint [R-]-carvone (1-cyclohex-2-enone + 2-methyl + 5R-isopropenyl) pine [S-]-limonene (cyclohexene + 1-methyl + 4S-isopropenyl) orange [R+]-limonene (cyclohexene + 1-methyl + 4R-isopropenyl) fish trimethylamine cabbage/ocean dimethyl sulfide butter diacetyl + acetoin vomit butyric acid pineapple methyl butyrate orange ethyl butyrate strawberry propyl butyrate, butyl butyrate pear/apricot pentyl butyrate glue methyl acetate pear ethyl acetate apple/banana butyl acetate, amyl acetate vinegar acetic acid goat cheese capric acid, caprylic acids popcorn 6-acetyl-1,2,3,4-tetrahydro-pyridine coconut gamma-nonalactone peach gamma-undecalactone garlic diallyl disulfide, diallyl trisulfide, diallyl tetrasulfide So I'd say that olfaction primitives probably number at least in the low hundreds. It seems as though just substituting a single functional group on an aromatic ring or changing the length of a carbon chain can affect human perception of the odor. Chirality usually matters. Orientation of the double bonds usually matters. Most frustratingly, concentration also matters. Indole smells like jasmine flowers at low concentrations and like poop at higher concentrations. It may well be that we don't have dedicated words for smells because the IUPAC chemical naming conventions make them unnecessary. Also, most people don't need them. Professional aromatists would probably just say the chemical name, or use the perfumery primitives like the plant essential oils or resins, ambergris, civet, castoreum, hyrax, musk, and beeswax. Esters are fruity. Linear terpenes are grassy or herby. Cyclic terpenes are woody or flowery. Substituted aromatics are flowery or herby. Amines are rotten or fishy. Thiols just plain stink. Wine snobs can probably just make up whatever words they want to describe their noses and bouquets, because their words don't really transmit meaning most of the time, anyway.