Amino acid-catalyzed conversion of citral: cis-trans isomerization and its conversion into 6-methyl-5-hepten-2-one and acetaldehyde.
Under alkaline conditions, amino acids or proteins catalyze the deacetylation of citral, a major aroma component, resulting in methylheptenone and acetaldehyde formation. 3-Hydroxycitronellal is an intermediate in this reaction. Amino acids also catalyze the cis-trans isomerization of the pure isomers of citral, geranial, and neral. Most likely the amino acids are involved in stabilizing intermediates of the isomerization and deacetylation reaction of citral. On the basis of the findings presented, some consequences for the application of citral, or its isomers, in food are discussed.
Wolken
W A
WA
Division of Industrial Microbiology, Department of Food Technology and Nutritional Sciences, Wageningen University and Research Centre, Wageningen, The Netherlands. wout.wolken@imb.ftns.wau.nl
ten Have
R
R
van Der Werf
M J
MJ
D000079:Acetaldehyde / Q000032:analysis; D000080462:Acyclic Monoterpenes; D000596:Amino Acids / Q000737:chemistry*; D002384:Catalysis; D002849:Chromatography, Gas; D007659:Ketones / Q000032:analysis; D039821:Monoterpenes; D009812:Odorants; D011506:Proteins / Q000737:chemistry; D013237:Stereoisomerism; D013729:Terpenes / Q000737:chemistry*
D000080462:Acyclic Monoterpenes; D000596:Amino Acids; D007659:Ketones; D039821:Monoterpenes; D011506:Proteins; D013729:Terpenes; C029750:methylheptenone; D000079:Acetaldehyde; C007076:citral