Download Cereal Grains Cereal grains What is a fruit? What is a seed?

Cereal Grains
Cereal grains
These are the fruits of grasses which are cultivated to produce food. They are caryopsis (see below)
of the Poaceae family (or true grasses) and include barley, oats, maize, wheat and rice as well as
10,000 other species.
Plant reproduction
The flower is the reproductive system of the plant which eventually produces a seed to keep the
species alive. The fruit has two functions – one to protect the seed (the new generation) and for
seed dispersal. Animals or birds eat the fruit and seeds, and then disperse the seeds over a wide
area. The seeds of flowering plants are surrounded by a tissue called the fruit, which may be fleshy
or dry.
What is a fruit?
The ovary is the female reproductive structure of a flower which usually develops into the fruit
carrying the seed. A “fruit” is the fleshy tissue that surrounds the seed and is called the pericarp. This
is best seen in stone fruit like peaches with a large fleshy pulp (pericarp) and a single large stone
(seed).
What is a seed?
Seeds develop inside the ovary. Normal fruit contains the skin, fruit pulp or pericarp, seed coat and
seed.
A Caryopsis is where the fruit and seed coat are fused so there is no fleshy pulp – just the skin and
the seed. Cereal grains are caryopsis, so that’s why grains are not fleshy.
Seeds usually have a seed coat, embryo (or baby plant) and endosperm (sugary food for the seed)
whereas grains also include the ovary. So the difference between a seed and a grain is –
grains include the ovary, seeds do not.
What is a nut?
In a true nut the entire pericarp of the ovary forms a hard dry wall around a single seed (so no
pericarp or flesh, just the hard shell).
So you can see grains, seeds and nuts are very similar – there are just a few
biological differences.
Scientists still argue over these definitions and some plants don’t fall neatly into these precise
categories.
What is a vegetable?
The culinary designation of “vegetable” is based on the use of the plant part
Vegetables are actually various plant parts; some are fruits (e.g., tomatoes and peppers), leaf stalks
(celery), leaf blades (spinach), lateral buds (Brussels sprouts), young shoot (asparagus), massive
flowering structure in bud stage (broccoli), root (sweet potato), underground storage stem (white
potato).
Development of Grain Cereals or grains
The first grain cereals were developed 12,000 years ago in the Fertile Crescent which is now Iraq and
also Turkey. These early grains included barley, emmer and einkorn – the Neolithic founder crops.
The ancient Egyptians also developed bread making and ovens.
In recent times, maize, wheat and rice together account for 87% of all grain production worldwide,
and 43% of all food calories, while the production of oats and rye have drastically fallen.
In 2010 world production of wheat was 651 million tons, making it the third most-produced cereal
after maize (844 million tons) and rice (672 million tons)
The most recent classification of the grass family recognizes 12 subfamilies:
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Anomochlooideae, a small lineage of broad-leaved grasses
Pharoideae, a small lineage of grasses of three genera
Puelioideae, a small lineage of the African genus Puelia
Pooideae, including wheat, barley, oats, brome-grass (Bromus), reed-grasses (Calamagrostis)
and many lawn and pasture grasses
Bambusoideae, including bamboo
Ehrhartoideae, including rice and wild rice
Aristidoideae
Arundinoideae, including giant reed and common reed
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Chloridoideae, including the lovegrasses (Eragrostis, about 350 species, including teff),
dropseeds (Sporobolus, some 160 species), finger millet, and the muhly grasses
Panicoideae, including panic grass, maize, sorghum, sugarcane, most millets, fonio,
and bluestem grasses
Micrairoideae
Danthonioideae, including pampas grass
Triticum species – a sub group of Pooideae, includes 4 wild species of wheat as well as commercial
wheat, spelt, durum(pasta), emmer and einkorn, although scientists originally had these species in
another group. All contain gliadin- the wheat protein in gluten. Spring fertilizers, herbicides,
fungicides and growth regulators may all be sprayed on wheat.
There is a theory that cereal grains produce chemicals as a natural deterrent to prevent animals
eating the grasses – these are called secondary metabolites.
Phytates occur in grains like wheat, rice, and soy and may interfere with mineral absorption such as
iron, zinc, manganese and calcium. Phytates are reduced by cooking, soaking in lemon juice or
yogurt and sprouting. Probiotics are an important source of the enzyme phytase which helps break
down phytates. Phytates may be necessary for the plant to store phosphorus.
Phytates may cause mineral deficiency in populations where there is high dependence on these
grains e.g. poor developing countries where they depend on cereals for most of their food.
Lectins occurring in cereal grains have been shown to be readily absorbed into the body and cause
immune reactions. Particularly lectins have the potential to interfere with insulin and sugar
metabolism.
Pseudocereal grains
Starchy grains from broadleaf (dicot) plant families:
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amaranth (Amaranth family)
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quinoa (Goosefoot family)
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buckwheat (Smartweed family)
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Grain legumes or pulses
Members of the (pea family). Pulses have higher protein than most other plant foods. They may also
contain starch or oil. Most widely grown include:
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soybean
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common bean
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chickpea
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lima bean
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runner bean
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pigeon pea
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lentil
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field pea or garden pea
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lupin
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mung bean
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fava bean
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peanut
Oilseeds
Grains grown primarily for the extraction of their edible oil.
Mustard family
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rapeseed (including canola)
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India mustard
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black mustard
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Aster Family
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sunflower seed
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safflower
Chia- member of the mint family
Other families
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flax seed (Flax family)
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hemp seed (Hemp family)
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poppyseed (Poppy family)
Summary
There are many types of cereal grain and many types of wheat. It is worth noting that Chia,
Buckwheat and Quinoa are not cereal grains – quinoa and buckwheat are pseudocereals and chia is
from the mint family. These are great alternative grains as these have a good spread of all essential
amino acids and plenty of Omega 3s.
Many people seem to have problems with members of the Triticum family but can tolerate other
grains. Of course, there is a world of difference between an ancient grass grown 3000 years ago and
our modern cultivated wheat sprayed with chemicals and grown on sewage sludge. Perhaps humans
are reacting to the chemical residues rather than the gliadin. We just don’t know at present. What
we do know is that many people feel much better taking all grains from the Triticum family out of
their diet. Some people can tolerate other triticae like spelt and einkorn, others feel better with no
cereal grains at all.
This article is for your information only, to help you understand the different types of grains and
their definition. You do not need to remember any of the names and this will not be assessed in the
Cert IV.
Dr Shirley Mcilvenny
24/9/2012