Natural aroma chemicals for use in foods and beverages - Natural Food Additives, Ingredients and Flavourings - page 226

named lulo del Chocó ('chocolate banana' in Portuguese?), things are the reverse
with the S forms dominating (Brown 2007).
By using different culture media, both high- R and low enantiomeric excess
gamma -lactones can be obtained by fermentation of natural long-chain carboxylic
acids; essentially we have enzymatic oxidation at position 3 followed by
cyclisation. The organoleptic properties of the high- R forms are subtly different to
that of the R / S mixture, and this gives the fl avourist an extra opportunity to
infl uence the fl avour.
We have a similar situation with the six-membered delta -lactones. For example,
the delta-decalactone in raspberries is 98% S -isomer [10.58], whereas in peach
the situation is reversed at 97% R -isomer [10.59], and in cheddar cheese we have
a 72:28 mixture!

[10.58] [10.59]

10.8 Future trends
For those of us not possessed of crystal balls, this is an impossible question to
answer. The marketing departments of fl avour and food companies, the
supermarkets and other major retailers are unlikely to reverse their policies of
promoting their subliminal (and sometimes not so subliminal) formula of 'natural
= healthy'. This also chimes with the current general 'fl ight from reason' in which
scientifi c thought takes second place to our 'gut feelings' and general vague
spirituality - whatever that means. All too often, 'science' is presented as some
sort of conspiracy theory, something that THEY want you to think (whoever
THEY are is never specifi ed). A brief session on the blogs and message boards of
the internet will demonstrate all too clearly that we are in a 'golden age' of
conspiracy theories and general irrationality. In this climate, there's unlikely to be
any opposition to the naturals concept.
In terms of new aroma chemicals, continuing developments in isolations and
(especially) microbial transformations means that more materials become
available. However, the industry is on a knife edge. Growing populations,
especially in the developing countries, may lead to pressure to stop the use of
valuable agricultural land to, in effect, 'grow chemicals'. At the moment it's a
rhetorical question (to which the author does not know the answer), but is the best
use of land in India to grow mint in order to make menthol, when the same material
is available from non-agricultural sources? Will a time come when 'petrochemical',
currently a term of abuse, becomes fashionable - perhaps in the form 'this fl avour
contains no materials derived from food crops'? There is added irony in that the
yields of natural aroma chemicals could be increased by genetic modifi cation of

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