Agriculture Reference
In-Depth Information
15
Herbs, Spices and Flavourings
Graham Farrell
Herbs and spices are used in small quantities to supplement
the flavour and aroma of staple foods. The International
Standards Organisation defines spices as 'Vegetable
products or mixtures thereof, free from extraneous matter,
used for flavouring, seasoning and imparting aroma to
foods'. Peter (2001) distinguished herbs from spices by
describing the former as the dried leaves of aromatic
plants used to impart flavour, odour or colour to foods,
usually traded separately from stems and leaf stalks.
Examples include mint, basil and rosemary. Many
herbs, of course are sold in fresh form. Flavourings, in this
account, refer to compounds in which the aromatic
essence is derived from a post-harvest treatment of the
raw ingredient, such as soy sauce made from fermented
soya beans.
Herbs and spices have always been important
constituents of the human diet, providing variation and
adding interest to the bland taste of many staples.
Historically, some have also been valuable in food
preservation and disguising off-flavours, particularly when
transportation times were long and preservation techniques
were limited to salting or drying (Cantwell & Reid 1993).
Today the main commercial form of herbs and spices is the
dried product. Most spices and many herbs are grown in
tropical and semi-tropical countries and so there is little
seasonality in harvesting and they are available fresh all
year round (FAO 2002). However, their use is world-wide,
and so the dried forms are cheaper and easier to transport,
and have much longer shelf lives than fresh produce. At
one time, fresh herbs were grown in kitchen gardens and
available only in local markets, despite having a better
flavour than the dried product. It is only recently that
improvements in harvesting, processing and packaging
techniques have made it economical for supermarkets and
convenience stores to stock fresh herbs (Cantwell & Reid
1993). This has coincided with increasing demand for
some herbs as a result (in developed countries) of their
being featured on popular television cookery programmes
and an increase in foreign tourism that exposes tourists to
spicy, indigenous cuisines in the tropics. Basil and rocket
are good examples of this in the United Kingdom.
Herbs and spices are complex structurally and
physiologically. They may consist of leaves, stems, roots,
flower parts, flower buds, seeds or seed structures, which
may be mature or immature. Most herbs are harvested soft
or semi-woody and those that are harvested whole may
contain leaves at different physiological states. Although
this diversity suggests that post-harvest treatments should
be tailored to suit the individual characteristics of each
plant, most herbs are handled in a similar fashion to other
leafy vegetables (Cantwell & Reid 1993) with little or no
differentiation between handling methods.
Although supply of fresh herbs has increased through
the major food distribution channels, marketing has not
always been successful. Given their soft, leafy habit many
herbs are perishable. Despite their high value the
comparatively small quantities sold means that even a
small stock takes time to turn over. In addition, marketing
has relied on similar strategies for all herbs. In Australia,
for example, it was apparent that the industry was unaware
