cereal grains Flashcards
why are cereal grains important
widely available at a low cost
nutrition, energy
feed for livestock use
economic important to farmers
fuel
grain is durable- long term storage
different grains grow in different climates
food, staple in diet
food security
enviroment
what is a cereal grain
starchy grains from plants
what is a cereal grain used for?
breakfast foods, flours, breads, pastas, starches, fermented beverages, etc
what is a whole grain?
contains endosperm, bran, and germ,
when processed it should still have the same rich balance as the origianal grain
humans need atleast 3 servings of whole grain per day
examples of whole grains (with gluten)
wheat, rye, barley, oats, triticale
examples of gluten free whole grains
amaranth, buckwheat, millet, quinoa, teff, rice, corn, sorghum
three parts of canadas food guide
fruits and vegetables, protein, whole grains
refined or white vs enriched
refined, bran and germ are removed, leaving only the endosperm
enriched, bran and germ are removed, then vitamins/minerals are added back in after processing
how much of the calories in a human diet come from cereal grains, how much protein
75% of each
what are kernels of cereal grains called?
fruits
the fruit is a dry, single seeded _________ that remains intact on maturity
caryopsis
what is the bran
pericarp or fruit coat acts to protect and support the growth of the endosperm and embryo
seed coat (testa) - pigmented layer
what is the endosperm
aleurone is a single layer at the inner cite of the bran. it contains most of the minerals, vitamins, phenolic antioxidants, and lignans of the wheat grain
the starchy endosperm is the major storage tissue, storing both starch and protein. supplies nutrients for plant growth, yield and quality
what is the germ
where new wheat sprouts occur, rich in nutrients
compostion of cereal grain
65-70% starch
10-15% protein
10-30% fibre
2-10% lipid
2-4% minerals
what causes variation in composition
genetics, environment, agronomic practices
what is dry milling
to separate fruit structures from seed
how many million tons of wheat does Canada produce in a year (2017)
30
two most important commercial species are
triticum aestivium L (common wheat)
triticum durum desf (durum wheat)
Characteristics of kernels
deep ventral crease, 9-15% protein 65-70% starch, 2%lipids
utilization of wheat
roller milled into flour or semolina
by-products are bran and germ
flour/semolina +water+mixing= gluten development=dough
fermentation = fuel alcohol, beer, distilled beverages
wet milling = gluten and starch
objectives of roller milling
seperation of bran 23% germ embryo2% and starchy endosperm 75%
reduction of starchy endosperm to semolina ie coarsely milled durum wheat or flour
refined flour
has enhanced appearance, palatability, quality(shelf life) and functionality
loss of nutritional value fibre protein lysine vitamins and minerals
grading and qualtity of wheat
quality is the degree to which something is suitable for a particular end use
the quality of wheat is determined by both genetics and the enviroment
wheat is segregated into market classes on the basis of growth habit colour hardness protein content gluten strenght and end use functionality
market classees of wheats
durum wheats highest protein pasta CWAD
hard wheats high protein pan breads
medium hardness, medium protein wheats french breads, oriental noodles,
soft, low proteins
grading system is largely visual
principal grading factors are test weight and degree of soundness, test weight is positively correlated with flour yield
degree of soundness is related to __________
flour yield, flour colour, dough handling properites, loaf volume and height, crumb and crust colour
soundness factors
frost damage, maturity, bleaching, springing, sprouting, disease, insect damage
flour protein is ____________ with bread loaf volume
positively correlated
corn
native to central and south america
world production in 2017 just under 1.39 billion tons
leading producers= USA 371 million, china 259 million, brazil=98