Herbs and Spices

1
Herbs and Spices Herbs and spices are what make
our food enjoyable. They are essentially all
plant products, and mostly all get their flavor
from plant secondary chemicals. Spices come
mostly from tropical regions, herbs are more from
temperate areas. The herbs flavor generally
comes from aromatic leaves. The aroma comes from
volatile oils. Further, many are essential oils
built from a basic unit that is a terpene
A diterpene phosphate, the carbon backbone is
C10H16
2
The basic unit for these terpenes is C5H8 , but
multiples of this unit are what we find as the
essential oils. Wikipedia lists more than 30
herbs used in cooking of various international
cuisines. We cant begin to consider all of them.
Among the more important ones are From the mint
family (Lamiaceae) peppermint, spearmint,
marjoram, oregano, rosemary, thyme, sage, savory
and basil
peppermint oregano
sweet basil
3
From the parsley family (Apiaceae) parsley,
dill, caraway From the mustard family
(Brassicaceae) mustard, horseradish (in the
mustards the flavour is released by a reaction
between an enzyme, myrosin, and sinigrin (in
stronger black mustards) or sinalbin (in milder
white mustards).
parsley
caraway
4
The reaction releases volatile essential oils.
Preparation with acid (vinegar) causes the
reaction (and the flavour) to last much longer.
wasabi
mustard
horseradish
5
From the lily family (Liliaceae) onion, garlic,
leek, shallot, and chives (all contain closely
related sulphurous compounds the one in garlic
is called allicin since onions, garlic, etc. are
all in the genus Allium. All these species seem
to originate in central Asia. The individual
species are Onions Allium cepa Garlic A.
sativum Leeks A. porrum Shallots A.
ascalonicum Chives A. schoenoprasum
garlic in flower
6
If you need an excuse to eat onions and garlic,
heres what allicin is believed to do 1.
inhibits pathogenic bacteria by blocking enzymes
they use to penetrate healthy cells 2.
inhibits the formation of blood clots (that
should lower the probability of heart
attacks and strokes) 3. inhibits cholesterol
synthesis (lowering LDL and probably
triglycerides in circulation) The only problem
with consumption of onions, garlic, etc. is that
the sulfurous compounds directly consumed and
modified into others enzymatically enter the
circulation from the digestive tract, are
circulated to the lungs, and diffuse into the
gases of the lungs. When you exhale, you smell of
the sulfur compounds.
7
Many herbs were used for centuries as natural
dyes. Some are also used as spices (note the
sneaky transition). Among them Tumeric (or
turmeric Curcuma longa, in the same family as
ginger) a bright yellow rhizome. The active
ingredient as a spice is curcumin. It is actually
not a very good dye for cloth, because it fades
readily in light.
However, it is a widely used food dye. It is the
reason mustard and Indian curry powder are
yellow. It also has uses in medicine It inhibits
the plaques that characterize Alzheimers, it
helps with STDs chlamydia and gonorrhea, and has
been suggested as an anti-cancer drug.
8
Indigo was an herbal dye obtained from Indigofera
tinctoria. Aztecs used indigo to dye cloth, and
its use continued into the 20th century before
replacement by a synthetic dye. Its indigo dye
that colours our bluejeans. The Celts went into
battle having stained their faces and bodies
using a temperate plant (Isatis tinctoria) that
has the same chemical (indigotin) in the leaves.
Think of Mel Gibson playing William Wallace in
Braveheart.
9
There are closely related species, with flowers
that are electric blue in midwestern prairies.
Herbal blue dyes were rare so were herbal red
dyes. The one that was used for centuries was the
madder plant (Rubia tinctorum). This is the plant
the British army used to dye the red coats they
were famous for at the time of the American
Revolution. The plant is in the same family as
coffee (remember those red fruits?)
10
Another red dye plant, of great importance in
science, was a bean known to the Aztecs for its
dye quality, and later used as a stain in
cellular microscopy, Haematoxylium spp.
11
The dye system used in microscopy combined
hematoxylin (red) with eosin (blue) that stained
different parts of tissues and cells. Hematoxylin
has not been replaced with a synthetic dye.
This is a picture of lung tissue from someone
with emphysema
12
Table 17B in the text lists a number of other
plants used as dyes and the colours they produce.
Among the more common Black walnut (Juglans
nigra) the pulp surrounding the walnut is used
as a dark brown dye.
Various Coreopsis species flower heads
(basically petals) are used to produce an orange
dye.
13
The outer, dry layers of yellow onion (Allium
cepa) were used to make a dye to colour cloth
burnt orange.
Lastly, what seems like an unlikely colour from
the colour of the plant tissue extracted a blue
or lavender dye extracted from the outer leaves
of red cabbage (Brassica oleracea).
14
Spices Definition (Oxford English Dictionary)
One or other of various strongly flavored or
aromatic substances of vegetable origin, obtained
from tropical plants, commonly used as
condiments. Spices are typically of tropical
origin. They are aromatic plants parts leaves,
twigs, bark, flowers or other plant parts. The
search for spices was one of the driving forces
in world exploration. Going back to the heyday of
the Egyptian pharaohs, herbs and spices were in
common use. There was, even then, an established
spice trade between the Mid-East and Southeast
Asia and China.
15
Arab traders were the agents by the time of the
Golden Age of Greece. Alexander the Great built
Alexandria as the key trade center between Asia
and Europe, and the key product in this trade was
spices. Marco Polo traveled throughout much of
China, but also visited (and later wrote about)
Java and India. The spices he described included
pepper, cinnamon and ginger. Overland trade was
slow, inefficient, and subject to seizure along
the route. The exploration of navigators like
Vasco de Gama, Christopher Columbus and others
was a search for a sea route from Europe to
Southeast Asia, China and India. It was Ferdinand
Magellan who discovered a route to the Spice
Islands, where cloves, nutmeg and mace were
native, in the course of his round-the-world
voyage.
16
(No Transcript)
17
Much more recently, a voyage by Alfred Russell
Wallace was duplicated to show English
schoolchildren the Spice Islands. Apparently it
is a tricky and dangerous sailing trip, and
Wallaces accounts tell much about his travails.
18
Originally, most spices came from the Old World.
More recently a number of New World spices have
been added to our gustatory spectrum. Old World
spices Cinnamon there are two plant sources,
one more properly called cassia (Cinnamomum
cassia) from southeast Asia, and the other the
higher quality cinnamon (Cinnamomum zeylandicum
or aromatica) native to India and Sri Lanka. The
spice we use is the inner bark of the tree for
cinnamon or the whole bark for cassia. That inner
bark curls as it dries and forms what we call
cinnamon sticks. Broken pieces are ground into
cinnamon powder.
19
(No Transcript)
20
Pepper here we need to be careful, there are
two very different kinds of plants described as
peppers. The black and white pepper you grind
comes from Piper nigrum, and are the dried
berries of a climbing vine native to India and
the East Indies.
Black pepper comes from picking these green
berries and allowing them to dry, blacken and
shrivel. White pepper comes from allowing the
berries to ripen on the vine, then removing the
hull, leaving the whitish seed kernel within.
21
New World peppers are completely separate. They
are in the genus Capsicum, of which there are 5
major species, but probably thousands of
varieties. All are in the same family
(Solanaceae) as tomatoes, eggplants, and tobacco.
To separate them, sometimes New World peppers are
called chili peppers. They have been in
cultivation in the Americas for at least 9,000
years. Heat among these peppers is measured on
a scale called Scoville units. It comes from
alkaloids primarily in the ribs that seeds are
attached to within the pepper and the seeds
themselves. The most important is capsaicin.
Capsaicin is the active ingredient in pepper
spray. Heat is not necessarily evident from what
species a capsicum pepper is in. For example,
both ordinary bell peppers and cayenne peppers
are varieties of Capsicum annuum (Scoville units
lt1 to 40,000).
22
The hottest peppers are the habanero or Scotch
bonnet peppers (Capsicum baccatum) with a
Scoville rating of 100,000 300,000. All these
peppers originate in southern Mexico and Central
America.
Scoville units 100,000 350,000
Thai peppers 50,000 100,000
Jalapenos 2,500 - 8000
Green pepper 0
23
As a comparison, police pepper spray has a
Scoville rating of 500,000 5,300,000. Other old
world spices Cloves the unopened flower buds
of Eugenia aromaticum Nutmeg and Mace - from
Myristica fragrans native to the Spice Islands.
The species is dioecious (separate male and
female plants). Mace comes from a netlike aril
within the fruit. The dried seed within is
nutmeg.
24
Saffron comes from the stigmas of the flowers
of the autumn crocus, Crocus sativus. It is
native to the eastern Mediterranean and southwest
Asia (sometimes called Asia Minor). You can grow
it locally! However, it takes 800,000 stigmas to
make up one kilogram, and there are only 3 per
flower. It was used as a yellow dye, and is still
used in cooking both for flavor and to give a
yellow colour, for example in the rice of Spanish
paella.
25
Lastly, vanilla. It comes from the fruit pods
of the vanilla orchid, Vanilla planifolia. This
is a tropical, perennial vining orchid originally
from southern Mexico and Central America. Today,
the largest producer is Madagascar.
vanillin
26
To maximize fruit production, flowers are
hand-pollinated. The pods are picked green and
allowed to ferment for weeks to several months,
alternately heating and cooling them. During
this process they blacken. During the curing
there is a chemical change, and the pods produce
vanilla as crystals on the pods. The extraction
process percolates 35 alcohol over the cured
pods, which extracts both the vanillin and other
chemicals that contribute to the flavor.
27
Imitation vanilla is now produced (synthesized)
from clove oil, lignin, or coal tar. Now you know
why the real stuff tastes better.