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strength takes place rapidly. Like other sugars it is easily fermented and then gives
ethyl alcohol, a substance with a vast number of uses.
10. 4 Wheat Quality
The quality of flour is determined by the wheat from which it is milled and
the efficiency and skill with which the milling operations are performed. A good
wheat grist will produce a poor or unsatisfactory flour if the milling plant or the
operation of it is at fault, but a poor wheat grist will yield poor flour even on the
most modern and well-designed mill operated to the best advantage. The
formulation of a good wheat blend is, therefore, the first necessary step in the
production of good flour. The three criteria that a miller has to consider when
compounding his wheat blend, apart from factors such as bushel weight and
moisture content which influence milling behaviour, are protein content, protein
quality and diastatic activity. The first two of these three factors jointly determine
the physical properties of a dough made from the flour and hence the manner in
which it responds to the manual and mechanical treatment it receives in the bakery
and its ability to develop in the oven, while the third factor is an index of the power
of the flour to produce a sugar from its starch.
10.5 Advantages of Instant Yeast
Unlike conventional active dry yeast, which is dissolved in warm water for
proper hydration and activation, instant yeast may be added to the dough in much
the same manner as compressed yeast. However, due to its lower moisture and
higher activity, lower levels of instant yeast are required than compressed yeast.
While exact yeast levels are highly dependent upon product formulation and
processing conditions, it is generally recognized that instant yeast can be used to
replace compressed yeast at approximately one-quarter to one-third of the
compressed yeast level. In one laboratory test it was found that the instant yeast
could be used at just slightly more than one-third of the compressed yeast level.
This is compared to a nearly three-quarters replacement necessary for conventional
active dry yeast
A side-by-side comparison of white pan bread doughs containing regular active dry
yeast, instant yeast, and compressed yeast was made. After 15 minutes of
fermentation, all doughs appeared to be at essentially the same weight, indicating
no significant difference at that point in time. After 30 minutes of fermentation,
differences in dough weight were observed. The doughs made with instant yeast
and compressed yeast were higher than the dough made with regular active dry
yeast. After 45 minutes of fermentation time, the dough with the instant yeast was
high, and very similar to that with compressed yeast. The dough with the regular
active dry yeast was somewhat lower in volume, indicating slightly lower
fermentation characteristics.
28
strength takes place rapidly. Like other sugars it is easily fermented and then gives
ethyl alcohol, a substance with a vast number of uses.
10. 4 Wheat Quality
The quality of flour is determined by the wheat from which it is milled and
the efficiency and skill with which the milling operations are performed. A good
wheat grist will produce a poor or unsatisfactory flour if the milling plant or the
operation of it is at fault, but a poor wheat grist will yield poor flour even on the
most modern and well-designed mill operated to the best advantage. The
formulation of a good wheat blend is, therefore, the first necessary step in the
production of good flour. The three criteria that a miller has to consider when
compounding his wheat blend, apart from factors such as bushel weight and
moisture content which influence milling behaviour, are protein content, protein
quality and diastatic activity. The first two of these three factors jointly determine
the physical properties of a dough made from the flour and hence the manner in
which it responds to the manual and mechanical treatment it receives in the bakery
and its ability to develop in the oven, while the third factor is an index of the power
of the flour to produce a sugar from its starch.
10.5 Advantages of Instant Yeast
Unlike conventional active dry yeast, which is dissolved in warm water for
proper hydration and activation, instant yeast may be added to the dough in much
the same manner as compressed yeast. However, due to its lower moisture and
higher activity, lower levels of instant yeast are required than compressed yeast.
While exact yeast levels are highly dependent upon product formulation and
processing conditions, it is generally recognized that instant yeast can be used to
replace compressed yeast at approximately one-quarter to one-third of the
compressed yeast level. In one laboratory test it was found that the instant yeast
could be used at just slightly more than one-third of the compressed yeast level.
This is compared to a nearly three-quarters replacement necessary for conventional
active dry yeast
A side-by-side comparison of white pan bread doughs containing regular active dry
yeast, instant yeast, and compressed yeast was made. After 15 minutes of
fermentation, all doughs appeared to be at essentially the same weight, indicating
no significant difference at that point in time. After 30 minutes of fermentation,
differences in dough weight were observed. The doughs made with instant yeast
and compressed yeast were higher than the dough made with regular active dry
yeast. After 45 minutes of fermentation time, the dough with the instant yeast was
high, and very similar to that with compressed yeast. The dough with the regular
active dry yeast was somewhat lower in volume, indicating slightly lower
fermentation characteristics.
28
