Preparation of 3-Methylthiodecanal, a Flavour Compound

(S)-5-Methylhept-2-en-4-one is a key flavour compound in hazelnuts. We have performed its chiral-pool-based chemoenzymatic synthesis with 39% overall yield (73% ee). The four-step aldol-based sequence avoids the use of highly reactive and/or toxic reagents, does not require anhydrous conditions and uses only distillation as the purification method. Thus, such methodology represents a green and scalable alternative to only two stereoselective approaches towards this natural product known so far. In addition, we have designed and prepared a set of new (di)enones as achiral synthetic analogues of the title compound. The results of their sensory analyses clearly show that relatively minor structural changes of the natural molecule significantly alter its olfactory properties. Thus, simple (poly)methylation completely changes the original hazelnut aroma of (S)-5-methylhept-2-en-4-one and shifts the odour of its analogues to eucalyptus, menthol, camphor, and sweet aroma.

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Decreased quality and off-flavour compound accumulation of 3–10 kDa fraction of pine nut (Pinus koraiensis) peptide during storage

LWT ◽

10.1016/j.lwt.2017.05.032 ◽

2017 ◽

Vol 84 ◽

pp. 23-33 ◽

Cited By ~ 8

Author(s):

Songyi Lin ◽

Ruiwen Yang ◽

Sheng Cheng ◽

Ke Wang ◽

Lei Qin

Keyword(s):

Pinus Koraiensis ◽

Flavour Compound ◽

Pine Nut

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Production of a root-specific flavour compound, 2-hydroxy-4-methoxy benzaldehyde by normal root cultures ofDecalepis hamiltonii Wight and Arn (Asclepiadaceae)

Journal of the Science of Food and Agriculture ◽

10.1002/jsfa.1939 ◽

2004 ◽

Vol 85 (1) ◽

pp. 61-64 ◽

Cited By ~ 8

Author(s):

P Giridhar ◽

T Rajasekaran ◽

GA Ravishankar

Keyword(s):

Root Cultures ◽

Flavour Compound

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Contribution of lactic acid bacteria to flavour compound formation in dairy products

International Dairy Journal ◽

10.1016/0958-6946(95)00037-2 ◽

1995 ◽

Vol 5 (8) ◽

pp. 877-903 ◽

Cited By ~ 216

Author(s):

G. Urbach

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Dairy Products ◽

Compound Formation ◽

Flavour Compound

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Threonine aldolase and alcohol dehydrogenase activities in Lactobacillus bulgaricus and Lactobacillus acidophilus and their contribution to flavour production in fermented milks

Journal of Dairy Research ◽

10.1017/s0022029900023219 ◽

1983 ◽

Vol 50 (3) ◽

pp. 375-379 ◽

Cited By ~ 42

Author(s):

Valerie M. Marshall ◽

Wendy M. Cole

Keyword(s):

Alcohol Dehydrogenase ◽

Dehydrogenase Activity ◽

Lactobacillus Acidophilus ◽

Lactobacillus Bulgaricus ◽

Flavour Compound ◽

Threonine Aldolase ◽

Fortified Milk ◽

Alcohol Dehydrogenase Activity ◽

Aldolase Activity ◽

Acetaldehyde Production

SummaryCell-free extracts of both Lactobacillus bulgaricus and L. acidophilus demonstrated threonine aldolase activity, the end product of which was acetaldehyde, the major flavour compound of yoghurt. L. acidophilus also possessed an alcohol dehydrogenase activity capable of reducing acetaldehyde so that little yoghurt flavour was present in milks fermentation with this organism. Addition of threonine to fortified milk before fermentation with L. acidophilus increased acetaldehyde production and resulted in a well flavoured product similar to that of yoghurt made with L. bulgaricus. The contribution of these 2 enzymes to flavour production is discussed.

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