Headspace technology
{{Short description|Technique of gas chromatography}}
Headspace technology is a technique developed in the 1980s to elucidate the odor compounds present in the air surrounding various objects. Usually the objects of interest are odoriferous objects such as plants, flowers and foods.{{Cite journal|last1=Omar|first1=Jone|last2=Olivares|first2=Maitane|last3=Alonso|first3=Ibone|last4=Vallejo|first4=Asier|last5=Aizpurua-Olaizola|first5=Oier|last6=Etxebarria|first6=Nestor|date=2016-04-01|title=Quantitative Analysis of Bioactive Compounds from Aromatic Plants by Means of Dynamic Headspace Extraction and Multiple Headspace Extraction-Gas Chromatography-Mass Spectrometry|journal=Journal of Food Science|language=en|volume=81|issue=4|pages=C867–C873|doi=10.1111/1750-3841.13257|pmid=26925555|s2cid=21443154 |issn=1750-3841|url=https://figshare.com/articles/journal_contribution/5028548 }} Similar techniques are also used to analyze the interesting scents of locations and environments such as tea shops and saw mills. After the data is analyzed, the scents can then be recreated by a perfumer.
One of the early pioneers of this technology was Roman Kaiser who used it to measure and characterize the scents of tropical rainforests.{{citation |first=Roman |last=Kaiser |title=Environmental Scents at the Ligurian Coast |journal=Perfumer & Flavorist |year=1997 |volume=22 |pages=7–18}} Headspace techniques have since been used extensively to sample in vivo floral headspace of a large variety of numerous taxa and their aromatic compounds such as fatty acid derivatives (aldehydes, alcohols and ketones), benzenoids and isoprenoids.{{citation |first1=Jette T. |last1=Knudsen|first2=Lars |last2=Tollsten|first3=L.Gunnar |last3=Bergström |title=Floral scents—a checklist of volatile compounds isolated by head-space techniques |journal=Phytochemistry |year=1993 |volume=33 |number=2 |pages=253–280 |doi=10.1016/0031-9422(93)85502-i|bibcode=1993PChem..33..253K }}
Equipment
The headspace equipment involves a hollow dome or sphere-like objects which forms an airtight seal and surrounds the objects of interest. Inert gases are passed into the space containing the object or a vacuum is established such that the odor compounds are removed from the headspace.{{cite book | title = The Chemistry of Fragrances | first = Sell| last = Charles (Ed.) |author2=Karen Jenner| chapter = Chapter 14. The Search for Fragrance Ingredients| pages = 254–293 |publisher = Royal Society of Chemistry Publishing | isbn = 978-0-85404-824-3 | year = 2005| edition=2nd}} These compounds are in turn captured using a variety of techniques, among them cold surfaces, solvent traps, and adsorbent materials, with the latter techniques capable of longer periods of collection. The samples can then be analyzed using techniques such as gas chromatography, mass spectrometry, or Carbon-13 NMR.{{cite book | title = The Chemistry of Fragrances | first = Sell| last = Charles (Ed.) |author2=Robin Clery | chapter = Chapter 12. Natural Product Analysis in the Fragrance Industry| pages = 214–228 |publisher = Royal Society of Chemistry Publishing | isbn = 978-0-85404-824-3 | year = 2005| edition=2nd}}
Several companies have patented similar headspace technologies: