Leaves. The leaf is the manufacturing por¬
tion of the plant. Here photosynthesis takes
place. (See page 10.) In order to absorb
from the air the carbon dioxide necessary in
the formation of carbohydrates and to catch
the energy from the sun, surface is desirable.
So in the leaves the plant cells containing the
green chlorophyll are spread out on a net¬
work of cellulose. Since the carbohydrate
formed is rapidly transported to other por¬
tions of the plant, the leaves are low in
energy but are very valuable sources of min¬
erals and vitamins. They are the best vege¬
table sources of riboflavin.
All leafy vegetables contain calcium.
However, the calcium is utilized best from
those leaves containing no oxalic acid, such
as collards, turnip greens, mustard, and kale.
Spinach and beet tops contain undesirable
amounts of oxalic acid.
Leafy green vegetables, as a group, also
are useful sources of iron, of vitamin A, and
when eaten raw or lightly cooked, of vitamin
C. The bleached or pale inner leaves of
vegetables like cabbage and lettuce are less
useful as sources of these nutrients than green
leaves.
Fruits and Flowers. Tomatoes, eggplant,
and squash are typical examples of fruits
used as vegetables, while cauliflower, broc¬
coli, and globe artichokes are flowers. These
vegetables are not high in energy value,
but they are important on account of their
pleasing flavors and the minerals and vita¬
mins they contain. Tomatoes rank close to
citrus fruits as a source of vitamin C.
Pods and Seeds. Pods and seeds of legu¬
minous plants form an important group of
fresh vegetables. These seeds, even in im¬
mature form, are high in food nutrients.
Green beans are used pod and all. Peas, ex¬
cept one special variety, and lima beans are
shelled for use; cowpeas and black-eyed
peas also may be used fresh in the same way,
if collected while still immature and tender.
Certain varieties of soybeans are very palat¬
able when used in succulent form as a green
vegetable. They may be either shelled for
cooking or cooked in the pod. All this group
is higher in protein than other fresh vege¬
tables, the soybeans containing protein of
good quality. They are also good sources
of minerals and vitamins, especially the B
vitamins.
SELECTION AND BUYING
Green or succulent vegetables are highest
in quality and nutritive value immediately
after they are gathered. The maturing of
vegetables, like the ripening of fruits, is
brought about by enzymes and their action
continues after the vegetable is gathered.
Vegetables dry out easily and wilt quickly
after they have been picked. This is espe¬
cially true of the tender ones with high
water content, and without a protective
peel or skin.
Both enzymatic changes and loss of water
are most rapid in the leaves and growing por¬
tions. Leaves with their expanse of surface
lose water rapidly. The high water content
of the growing portions evaporates, causing
them to wilt and lose their crispness. Fruits
such as tomatoes, cucumbers, and squash,
which are covered by skins, and roots with
fibrous peel and low water content are less
vulnerable to loss of water. But these too
will shrivel if held under unfavorable con¬
ditions too long after gathering.
Page 64
Presented as published in 1935. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
AI-modernized reading of the original text
Leaves. The leaf is the manufacturing por¬ tion of the plant. Here photosynthesis takes place. (See page 10.) In order to absorb from the air the carbon dioxide necessary in the formation of carbohydrates and to catch the energy from the sun, surface is desirable. So in the leaves the plant cells containing the green chlorophyll are spread out on a network of cellulose. Since the carbohydrate formed is rapidly transported to other por¬ tions of the plant, the leaves are low in energy but are very valuable sources of min¬ erals and vitamins. They are the best vege¬ table sources of riboflavin.
All leafy vegetables contain calcium. However, the calcium is utilized best from those leaves containing no oxalic acid, such as collards, turnip greens, mustard, and kale. Spinach and beet tops contain undesirable amounts of oxalic acid.
Leafy green vegetables, as a group, also are useful sources of iron, of vitamin A, and when eaten raw or lightly cooked, of vitamin C. The bleached or pale inner leaves of vegetables like cabbage and lettuce are less useful as sources of these nutrients than green leaves.
Fruits and Flowers. Tomatoes, eggplant, and squash are typical examples of fruits used as vegetables, while cauliflower, broc¬ coli, and globe artichokes are flowers. These
vegetables are not high in energy value, but they are important on account of their pleasing flavors and the minerals and vita¬ mins they contain. Tomatoes rank close to citrus fruits as a source of vitamin C.
Pods and Seeds. Pods and seeds of legu¬ minous plants form an important group of fresh vegetables. These seeds, even in im¬ mature form, are high in food nutrients. Green beans are used pod and all. Peas, ex¬ cept one special variety, and lima beans are shelled for use; cowpeas and black-eyed peas also may be used fresh in the same way, if collected while still immature and tender. Certain varieties of soybeans are very palat¬ able when used in succulent form as a green vegetable. They may be either shelled for cooking or cooked in the pod. All this group is higher in protein than other fresh vege¬ tables, the soybeans containing protein of good quality. They are also good sources of minerals and vitamins, especially the B vitamins.
Green or succulent vegetables are highest in quality and nutritive value immediately after they are gathered. The maturing of vegetables, like the ripening of fruits, is brought about by enzymes and their action continues after the vegetable is gathered. Vegetables dry out easily and wilt quickly after they have been picked. This is espe¬ cially true of the tender ones with high water content, and without a protective peel or skin.
Both enzymatic changes and loss of water are most rapid in the leaves and growing por¬ tions. Leaves with their expanse of surface lose water rapidly. The high water content of the growing portions evaporates, causing them to wilt and lose their crispness. Fruits such as tomatoes, cucumbers, and squash, which are covered by skins, and roots with fibrous peel and low water content are less
vulnerable to loss of water. But these too will shrivel if held under unfavorable con¬ ditions too long after gathering.