Fruit may be either a laxative or an astringent or both, as
in the case of fruits which contain astringent substance in the
skin, while the pulp is laxative. Fruit is also valuable for its
antiscorbutic property and often seems to act as a mild and
ii
12 LABORATORY MANUAL OF FOODS AND COOKERY
beneficial diuretic. The cellulose is useful in giving bulk to the
food residues and preventing their stagnation in the intestine.
A given fruit often shows quite different properties at differ-
ent stages in ripening, the most distinct changes in composi-
tion being usually a decrease in acid and starch with an increase
in sugar content. Pectin substances present in underripe fruits
cause fruit juices to jelly.
The desirability of increasing the use of fruit as food and the
variety of attractive properties possessed by fruits and fruit
products, lend special interest to the subject of fruit cookery.
General rules for preparation :
Small and soft fruits need careful handling when washed. Fill
bowl with cold water, put fruit in and remove with strainer or per-
forated spoon in order not to crush.
Hard fruits, if small, may be washed in a colander under running
water, or if large wiped with a damp cloth.
Decayed spots, bruises, or worm holes should be removed, prefer-
ably with a silver knife.
Cover pared fruits with cold water until ready to cook.
Oranges, lemons, and grapefruit should be scrubbed with a brush ;
bananas peeled and scraped, raspberries and blackberries removed
from baskets with a fork to avoid crushing.
Dried fruits should be examined and washed in several waters.
Reasons for cooking fruit :
To soften cellulose.
In some instances to insure digestibility.
To further variety in serving.
In some instances to destroy bacteria.
How to purchase :
Fruits are economical when purchased in season, and if storage fa-
cilities allow, should be bought in quantity. Freshness and cleanli-
ness should receive first consideration. Dried fruits may take the
place of fresh fruits when the latter are not in season. The cost of
fruits varies with locality - - study the market in your own section.
FRUITS 13
EXPERIMENTS
Apple
15. 1 — Grate an apple into a bowl. With a wooden spoon
thoroughly mash the solid matter with the juice.
What change in color is observed?
16. - -Add about 2 tbsp. of water to the mixture obtained in Expt.
15, and strain the liquid through wet cheesecloth into a bowl. Filter
the juice through a wet fluted filter and keep it for Expt. 17 and 18
below. To portions of the apple pulp apply :
a. The Millon test ~ for protein.
b. The iodine test for starch.3
17.- -To small portions of the clear filtered apple juice obtained
in Expt. 16, apply the following tests:
a. Heat about 10 cc. to boiling in a test tube and notice
whether coagulation takes place. Filter through a wet fluted paper
and test the residue on the paper by adding a few drops of nitric
acid. If protein is present, it will be turned yellow by the nitric acid.
b. Test for starch by adding iodine solution. (The portion
of solution to which this test is applied must be cool.)
Page 8
Presented as published in 1916. 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
Fruit may be either a laxative or an astringent or both, as in the case of fruits which contain astringent substance in the skin, while the pulp is laxative. Fruit is also valuable for its antiscorbutic property and often seems to act as a mild and
beneficial diuretic. The cellulose is useful in giving bulk to the food residues and preventing their stagnation in the intestine.
A given fruit often shows quite different properties at different stages in ripening, the most distinct changes in composition being usually a decrease in acid and starch with an increase in sugar content. Pectin substances present in underripe fruits cause fruit juices to jelly.
The desirability of increasing the use of fruit as food and the variety of attractive properties possessed by fruits and fruit products, lend special interest to the subject of fruit cookery.
General rules for preparation :
Small and soft fruits need careful handling when washed. Fill bowl with cold water, put fruit in and remove with strainer or perforated spoon in order not to crush.
Hard fruits, if small, may be washed in a colander under running water, or if large wiped with a damp cloth.
Decayed spots, bruises, or worm holes should be removed, preferably with a silver knife.
Cover pared fruits with cold water until ready to cook.
Oranges, lemons, and grapefruit should be scrubbed with a brush ; bananas peeled and scraped, raspberries and blackberries removed from baskets with a fork to avoid crushing.
Dried fruits should be examined and washed in several waters.
Reasons for cooking fruit :
To soften cellulose.
In some instances to insure digestibility.
To further variety in serving.
In some instances to destroy bacteria.
How to purchase :
Fruits are economical when purchased in season, and if storage facilities allow, should be bought in quantity. Freshness and cleanliness should receive first consideration. Dried fruits may take the place of fresh fruits when the latter are not in season. The cost of fruits varies with locality - - study the market in your own section.
Apple
15. 1 — Grate an apple into a bowl. With a wooden spoon thoroughly mash the solid matter with the juice. What change in color is observed?
16. - -Add about 2 tbsp. of water to the mixture obtained in Expt. 15, and strain the liquid through wet cheesecloth into a bowl. Filter the juice through a wet fluted filter and keep it for Expt. 17 and 18 below. To portions of the apple pulp apply :
a. The Millon test ~ for protein.
b. The iodine test for starch.3
17.- -To small portions of the clear filtered apple juice obtained in Expt. 16, apply the following tests:
a. Heat about 10 cc. to boiling in a test tube and notice whether coagulation takes place. Filter through a wet fluted paper and test the residue on the paper by adding a few drops of nitric acid. If protein is present, it will be turned yellow by the nitric acid.
b. Test for starch by adding iodine solution. (The portion of solution to which this test is applied must be cool.)