Dextrose is the simple sugar that plants
build into starch. Another name for this
sugar is glucose . Dextrose is less soluble in
water and crystallizes more readily than
levulose. It forms very small crystals.
Manufacturers now reverse the process by
which plants form starch and make from
starch a sweet sirup, known as commercial
glucose. In the United States this is com¬
monly called corn sirup even when prepared
from other starches since it is frequently
made from cornstarch. It can be prepared
equally well from any of the starches. This
change is not complete, and the resulting
sirups are not pure dextrose but mixtures of
dextrose, maltose, and dextrins. (See cerelose,
p. 30.) *
Levulose occurs most abundantly in fruit
and for this reason is sometimes called fruc¬
tose or fruit sugar. It is present also in sirups,
honey being an especially rich source. Levu¬
lose is more soluble than dextrose and crys¬
tallizes with difficulty and so is rarely available
in crystalline form. It can be produced from
inulin, a starch-like carbohydrate which is
built in some plants from levulose instead of
dextrose. Artichokes and certain other
tubers contain inulin instead of starch.
Galactose does not occur in foods in free
form. It is one of the simple sugar compo¬
nents of lactose discussed below.
Disaccharides. The disaccharides are com¬
posed of two molecules of simple sugars.
These combine, giving off one molecule of
water as indicated by the following equation:
2(C6Hi20e) = C12H22O11 -f- H2O
The disaccharides occurring in food are
maltose, lactose, and sucrose.
Maltose is composed of two molecules of
glucose. It does not crystallize readily and is
therefore rarely seen in pure form. It is
present in commercial glucose, in small
amounts in cerelose, and in dextro-maltose,
which is sometimes used in infant feeding.
Lactose is the sugar found in milk. It
yields a molecule of dextrose and one of
galactose, a sugar not found in any quantity
in any other foodstuff.
Sucrose, formed from one molecule of
levulose and one "of dextrose, is the sugar
generally available in pure form. It occurs
naturally in many plants and is especially
concentrated in sugar cane, sugar beets, and
maple sap. It crystallizes readily and so is
easily separated from the plant sap or ex¬
tracted juice. This sugar is available com¬
mercially in various forms. Granulated sugar,
the form most used, is unmixed with any
other material and, practically speaking, is
chemically pure. For this reason sugar cook¬
ery is a good starting point for a study of the
chemical and physical changes brought about
when heat is applied to food constituents. In
making candy the action of moist and dry
heat on sugar may be studied, and the influ¬
ence of these changes noted. The basic
principles of sugar cookery worked out in
this way can be applied when sugar is used
in more complex mixtures.
SOURCES AND MARKET FORMS
Plants that store energy in the form of
sugar — sugar canes, beets, and sugar maples —
are the richest sources of sucrose, or granu¬
lated sugar. A less sweet crystalline mixture
of sugars known as cerelose is manufactured
from starch. Sirups, both natural and manu¬
factured, are important sources of sugars;
usually they are mixtures of sugars.
Page 24
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
Dextrose is the simple sugar that plants build into starch. Another name for this sugar is glucose. Dextrose is less soluble in water and crystallizes more readily than levulose. It forms very small crystals.
Manufacturers now reverse the process by which plants form starch and make from starch a sweet sirup, known as commercial glucose. In the United States this is com¬ monly called corn sirup even when prepared from other starches since it is frequently made from cornstarch. It can be prepared equally well from any of the starches. This change is not complete, and the resulting sirups are not pure dextrose but mixtures of dextrose, maltose, and dextrins. (See cerelose, p. 30.) *
Levulose occurs most abundantly in fruit and for this reason is sometimes called fruc¬ tose or fruit sugar. It is present also in sirups, honey being an especially rich source. Levu¬ lose is more soluble than dextrose and crys¬ tallizes with difficulty and so is rarely available in crystalline form. It can be produced from inulin, a starch-like carbohydrate which is built in some plants from levulose instead of
dextrose. Artichokes and certain other tubers contain inulin instead of starch.
Galactose does not occur in foods in free form. It is one of the simple sugar compo¬ nents of lactose discussed below.
Disaccharides. The disaccharides are com¬ posed of two molecules of simple sugars. These combine, giving off one molecule of water as indicated by the following equation:
2(C6Hi20e) = C12H22O11 -f- H2O
The disaccharides occurring in food are maltose, lactose, and sucrose.
Maltose is composed of two molecules of glucose. It does not crystallize readily and is therefore rarely seen in pure form. It is present in commercial glucose, in small amounts in cerelose, and in dextro-maltose, which is sometimes used in infant feeding.
Lactose is the sugar found in milk. It yields a molecule of dextrose and one of galactose, a sugar not found in any quantity in any other foodstuff.
Sucrose, formed from one molecule of levulose and one "of dextrose, is the sugar generally available in pure form. It occurs naturally in many plants and is especially concentrated in sugar cane, sugar beets, and maple sap. It crystallizes readily and so is easily separated from the plant sap or ex¬ tracted juice. This sugar is available com¬ mercially in various forms. Granulated sugar, the form most used, is unmixed with any other material and, practically speaking, is chemically pure. For this reason sugar cook¬ ery is a good starting point for a study of the chemical and physical changes brought about when heat is applied to food constituents. In making candy the action of moist and dry heat on sugar may be studied, and the influ¬ ence of these changes noted. The basic principles of sugar cookery worked out in this way can be applied when sugar is used in more complex mixtures.
SOURCES AND MARKET FORMS
Plants that store energy in the form of sugar — sugar canes, beets, and sugar maples — are the richest sources of sucrose, or granu¬ lated sugar. A less sweet crystalline mixture of sugars known as cerelose is manufactured from starch. Sirups, both natural and manu¬ factured, are important sources of sugars; usually they are mixtures of sugars.