Odour compounds

Watson SB (2003) Cyanobacterial and eukaryotic algal odour compounds signals or by-products ... 

Watson discusses the biological activity of algal odour compounds that are the primary cause of foul source-water odour and have been treated by industry as metabolic waste with focus on their removal (Watson 2003). That these compounds can also have multiple functions in the intact ecosystem is elaborated in this contribution. 

Use of carbon filter odour reduction is quite common at municipal wastewater treatment plants. The odour compounds are not destroyed in the filter, but only retained until the... 

Catalytic oxidation makes it possible to destroy odourous gases at temperatures lower than without catalysts. Low concentrations of odourous compounds and sulfuric odour compounds reduce the effect of the catalyst and thus limit the application of catalytic oxidation for control of odours at wastewater treatment plants. 

Cemy, C. and Grosch, W. 1993. Quantification of character-impact odour compounds of roasted beef. Z. Lebensm.-Unters. -Forsch. A 196 417-422. 

Schieberle, P., Gassenmaier, K., Guth, H., Sen, A., and Grosch, W. 1993. Character impact odour compounds of different kinds of butter. Le-bensm.-Wiss. Technol. 26 347-356. 

Aroma and odour compounds such as limonene, 3-carene, betamyrcene and terpinolene with 3-carene having the highest estimated concentration, were found only in the recycled HDPE. The levels of these fragrance and taste materials are, however, low compared to the levels of aliphatic hydrocarbons. Fragrance and flavour compounds such as limonene, 3-carene,... 

Chilli or paprika is used for flavour, not heat, in some cuisines. Flavour is a complex sensation determined in the mouth. One of the most potent volatiles known to humans is found in chilli, the pyrazine 2-methoxy-3-isobutyl-pyrazine, the green bell pepper smell. Reports indicate that humans can detect this odour at two parts per trillion. Luning et al. (1994) reported the presence of more than 80 odour compounds in C. annuum. C.frutescenscv. Tabasco contained 125 compounds whose relative abundance changed with the season of harvest. The composition of aroma compounds of Tabasco differed significantly from that of the green... 

Edinger, W.D., and SpKttstoesser, D.F., Production lactic add bacteria of sorbic alcohol, the precursor of geranium odour compound, Am. J. Enol. Vitic., 37, 34-38, 1986. 

Guth, H., Grosch, W. (1989) 3-Methylnonane-2,4-dione an intense odour compound formed during flavour reversion of soya-bean oil. Fat Sci. Technol. 91, 225-230... 

Table 26.1 Activated carbon doses required to reduce the concentration of odour compound MIB to a level acceptable to consumers...

In addition to triacylglycerols and free fatty acids, crude CNO contains about 0.5% of unsaponifiable matter, though the Malaysian standard (MS239 1987) allows a maximum level of 0.8% and Codex (2001) up to 1.5%. This material consists mainly of sterols, tocols, squalene, colour compounds, carbohydrates and odour compounds (such as lactones). The pleasant odour and taste of CNO when the oil is extracted from fresh material is mainly due to y- and 8-lactones, which are present in trace amounts (Young 1983). 

Treatment aims to meet drinking water guidelines. The removal of disinfection by-products (DBPs) and biodegradable organics are primary targets. Taste and odour compounds are also important. 

Pressure driven membrane processes do not retain dissolved gases such as CO a (Rohe et al. (1990)) and some taste and odour compounds. 

Chiral GC was under development and was being used successfully, for example for chiral dmg bioanalysis, at the same time as commercialised CSP for LC were breaking through. The technique received a boost when cyclodextrin GC phases came onto the market. However, with most drug bioanalysis being carried out by LC, and LC-MS in particular, chiral GC is more the preserve of application areas such as the analysis of odourous compounds [24] and the field of insect pheromones [25]. 

The Phenol Number is used as an index of carbon s ability to remove taste-and-odour compounds. 

Source LFllrich, F. and Grosch, W., Flavour deterioration of soya-bean oil identification of intense odour compounds formed during flavour reversion, Fat Science Technology, 90 932-6, 1988... 

Ullrich, F. and Grosch, W. Identification of the most intense volatile odour compounds formed during autoxidation of methyl linolenate at room temperature. J. Am. Oil Chem. Soc. 65, 1313-1317(1988). 

Ueno, T., H. Masuda, S. Muranishi, S. Kiyohara, Y. Sekiguchi, C.-T. Ho, Inhibition of the formation of off-odour compounds from citral in an acidic aqueous solution, in Flavour Research at the Dawn of the Twenty-First Century, J.-L. Le Quere, P.X. Etievant, Eds., Tec. Doc., Paris, 2004, p. 128. 

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