Heterocyclic Flavour Molecules

Many products from the flavour industry are primary products from renewable resources or secondary products obtained by chemical conversions of the primary products. In general these secondary products are key flavour chemicals with a high added value. The cost diiference between a precursor, the primary product and the flavour chemical can easily amount to a factor 20-1,000, especially when it concerns a natural flavour chemical. A large part of this cost reflects, of course, the efficiency of the reaction, the labour involved and the cost of the other reagents. 

Although quite often these flavour chemicals can be prepared from petrochemical sources, renewable resources are preferred by the flavour industry, because access to these renewable resources is very good and already existed when these companies were started. In addition, chemicals from renewable resources are natural, so they can be used in natural flavours and offer the possibility to be used for the production of natural secondary products. 

Lawrence BM (1993) In JanickJ, Simon JE (eds) New crops. Wiley, New York, p 620 Sanganeria S (2005) Perfum Flavor 30(7) 24 

Zaobang S (1995) CIFOR occasional paper 6. Center for International Forestry Research, 

Sell CS (2003) A fragrant introduction to terpenoid chemistry. Royal Society of Chemistry, Cambridge 

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Also heterocyclic flavour molecules can be formed from renewable resources. 3,5-Diethyl-1,2,4-trithiolane is an important molecule for onion flavours and can easily be prepared from propanal obtained by biotransformation and hydrogen sulflde (Scheme 13.17). A meat flavour molecule like thialdine [dihydro-2,4,6-trimethyl-l,3,5(4H)-dithiazine] can be prepared from acetaldehyde isolated from molasses and ammonium sulflde (Scheme 13.18). The bacon flavour substance 2,4,6-triisobutyl-5,6-dihydro-4H-l,3,5-dithiazine can be prepared from isovaleraldehyde prepared from essential oils and ammonium sulfide (Scheme 13.19). 

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