''Bread improvers." Many and various substances have been suggested
and tried as so-called "bread improvers." Malt preparations containing
both diastase and proteinase are sometimes added to dough. They are of
greater benefit if added to flours low in natural diastase. The rate of
diastatic activity may depend upon the relative percentage of starch which
is embedded in gluten, the size of the starch granules, and other factors.
With many granules embedded in gluten the diastase has less surface on
which to act. If the starch granules are smaller there is a relatively greater
area for the action of the diastase. However, Markley and Bailey in their
investigations found particle size did not determine diastatic activity, but
that the rate was affected by humidity of the granule surface, possibly be-
cause the granule wall is less resistant.
At present potassium bromate is commonly added to bread dough by
commercial bakers. j0rgensen states that it imparts a beneficial action
because it diminishes the action of the proteinase. Balls and Hale attribute
part of the improvement of bleaching and aging of flour to diminution of
proteinase activity. J0rgensen has applied for a patent in the United States
for using ascorbic acid as a bread improver, its beneficial effects being at-
tributed to its ability to depress plant-proteinases of the papain-type.
Imbibition of water during fermentation. Sharp and Gortner have found
that during yeast fermentation the imbibition of water increases to a maxi-
mum and then decreases. The increased imbibition during fermentation
is due to the increase in the hydration capacity of the glutenin. During
fermentation the acidity increases, but Johnson and Bailey have reported
that the acids of fermentation cannot alone produce all the changes that
occur during fermentation. The proteolytic enzymes by hydrolyzing a part
of the protein aid in softening of the gluten. Swanson and Working have
suggested that the mechanical action of the expanding gas by stretching
the gluten also aids in bringing about a modification of the gluten.
Dispersion of gluten during fermentation. Johnson and Bailey in study-
ing the efifect of hydrogen-ion concentration on dispersion of the gluten
of the flour found that as the acidity increased the percentage of proteins
dispersed or the protein in the aqueous extract of the fermented dough
increased. It is either very diflficult or impossible to collect the gluten from
a dough that has fermented sufficiently for baking, by washing it in water.
This in itself shows a change in the condition of the gluten.
Johnson and Bailey have reported the following amount of protein
dispersed, or in the aqueous extract, during fermentation of a soft-wheat
dough, without added salt. At an optimum pYi for baking the bread, more
than half the protein was in a dispersed phase.
Desirable acidity for bread. As fermentation of the dough progresses its
acidity is increased. Johnson has reported that some lactic and acetic acids
are formed during fermentation. Bailey and Sherwood have shown that in
LENGTH OF FERMENTATION PERIOD
433
TABLE 51 \ _
Effect of Fermentation upon Dispersion of Proteins of Flour
{Johnson and Bailey)
Hours fermented
pR
Dispersed
protein
based on proteins in flour,
per cent
0
5.95
15.14
2
17.70
4
....
20.60
6
5.49
31.76
8
5.12
77.22
10
4.60
87.42
12
4.26
89.42
16
3.92
92.14
18.5
3.86
93.70
Page 352
Presented as published in 1932. 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
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''Bread improvers." Many and various substances have been suggested
and tried as so-called "bread improvers." Malt preparations containing
both diastase and proteinase are sometimes added to dough. They are of
greater benefit if added to flours low in natural diastase. The rate of
diastatic activity may depend upon the relative percentage of starch which
is embedded in gluten, the size of the starch granules, and other factors.
With many granules embedded in gluten the diastase has less surface on
which to act. If the starch granules are smaller there is a relatively greater
area for the action of the diastase. However, Markley and Bailey in their
investigations found particle size did not determine diastatic activity, but
that the rate was affected by humidity of the granule surface, possibly be-
cause the granule wall is less resistant.
At present potassium bromate is commonly added to bread dough by
commercial bakers. j0rgensen states that it imparts a beneficial action
because it diminishes the action of the proteinase. Balls and Hale attribute
part of the improvement of bleaching and aging of flour to diminution of
proteinase activity. J0rgensen has applied for a patent in the United States
for using ascorbic acid as a bread improver, its beneficial effects being at-
tributed to its ability to depress plant-proteinases of the papain-type.
Imbibition of water during fermentation. Sharp and Gortner have found
that during yeast fermentation the imbibition of water increases to a maxi-
mum and then decreases. The increased imbibition during fermentation
is due to the increase in the hydration capacity of the glutenin. During
fermentation the acidity increases, but Johnson and Bailey have reported
that the acids of fermentation cannot alone produce all the changes that
occur during fermentation. The proteolytic enzymes by hydrolyzing a part
of the protein aid in softening of the gluten. Swanson and Working have
suggested that the mechanical action of the expanding gas by stretching
the gluten also aids in bringing about a modification of the gluten.
Dispersion of gluten during fermentation. Johnson and Bailey in study-
ing the efifect of hydrogen-ion concentration on dispersion of the gluten
of the flour found that as the acidity increased the percentage of proteins
dispersed or the protein in the aqueous extract of the fermented dough
increased. It is either very diflficult or impossible to collect the gluten from
a dough that has fermented sufficiently for baking, by washing it in water.
This in itself shows a change in the condition of the gluten.
Johnson and Bailey have reported the following amount of protein
dispersed, or in the aqueous extract, during fermentation of a soft-wheat
dough, without added salt. At an optimum pYi for baking the bread, more
than half the protein was in a dispersed phase.
Desirable acidity for bread. As fermentation of the dough progresses its
acidity is increased. Johnson has reported that some lactic and acetic acids
are formed during fermentation. Bailey and Sherwood have shown that in
LENGTH OF FERMENTATION PERIOD
433
TABLE 51 \ _
Effect of Fermentation upon Dispersion of Proteins of Flour
{Johnson and Bailey)
Hours fermented
pR
Dispersed
protein
based on proteins in flour,
per cent
0
5.95
15.14
2
17.70
4
....
20.60
6
5.49
31.76
8
5.12
77.22
10
4.60
87.42
12
4.26
89.42
16
3.92
92.14
18.5
3.86
93.70