CONTROLLING FERMENTATION

Proper fermentation—that is, fermentation that produces a dough that is
neither underripe (young) nor overripe (old)—requires a balance of time,
temperature, and yeast quantity.

TIME
Fermentation times vary, so the time to punch the dough is indicated not by
clock but by the appearance and feel of the dough. Fermentation times given
in the formulas are guidelines only.
To vary the fermentation time, you must control the dough temperature
and the amount of yeast.

TEMPERATURE
Ideally, dough is fermented at the temperature at which it is taken from the
mixer. Large bakeries have special fermentation rooms for controlling
temperature and humidity, but small bakeshops and restaurant kitchens
seldom have this luxury. If a short-fermentation process is used, however, the
fermentation is completed before the dough is greatly affected by changes in
shop temperature.

Water Temperature
Dough must be at the proper
temperature, usually 78° to 80°F
(25.5° to 26.7°C), in order to ferment
at the desired rate. The temperature
of the dough is affected by several
factors:
• Shop temperature
• Flour temperature
• Water temperature
Of these, the water temperature
is the easiest to control in the small
bakeshop.Therefore, when the water
is scaled, it should be brought to the
required temperature.On cold days, it
may have to be warmed, and on hot
days, using a mixture of crushed ice
and water may be necessary. Also, if a
long fermentation is used, the dough
temperature must be reduced in
order to avoid overfermenting.

YEAST QUANTITY
If other conditions are constant, the fermentation time may be increased or
decreased by decreasing or increasing the quantity of yeast (see procedure
below). In general,use no more yeast than is needed.Excessive yeast results in
inferior flavor.
Small Batches
When very small quantities of dough—only a few pounds—are made, the
dough is more likely to be affected by shop temperature. Thus, it may be
necessary to slightly increase the yeast quantity in cool weather and slightly
decrease it in hot weather.

Procedure for Modifying Yeast Quantities
1. Determine a factor by dividing the old fermentation time by the fermentation time
desired.
2. Multiply this factor by the original quantity of yeast to determine the new quantity.
× old yeast quantity = new yeast quantity
Example: A formula requiring 12 oz yeast has a fermentation time of 2 hours at 80°F.
Caution: This procedure should be used within narrow limits only. An excessive
increase or decrease in yeast quantities introduces many other problems and results
in inferior products.
old fermentation time
______________
new fermentation time
Procedure for Determining Water Temperature
1. Multiply the desired dough temperature by 3.
2. Add together the flour temperature and room temperature, plus 20°F (11°C) to allow for
the friction caused by mixing (see note).
3. Subtract the result of step 2 from that of step 1. The difference is the required water
temperature.
Example: Dough temperature needed = 80°F
Flour temperature = 68°F
Room temperature = 72°F
Machine friction = 20°F
Water temperature = ?
1. 80° × 3 = 240°
2. 68° + 72° + 20° = 160°
3. 240° − 160° = 80°
Therefore, the water temperature should be 80°F.
Note: This procedure is precise enough for most purposes in the small bakeshop.
However, there are other complications, such as variations in machine friction, that
you may want to consider if you wish to be even more exact.

OTHER FACTORS
The salt in the formula, the minerals in the water, and the use of dough
conditioners or improvers affect the rate of fermentation.
Water that is excessively soft lacks the minerals that ensure proper gluten
development and dough fermentation. On the other hand, water that is very
hard—that is, has high mineral content and, as a result, is alkaline—also inhibits
the development of the dough.These conditions are more of a problem
for lean doughs than for rich doughs. In most localities, small bakeshops can
overcome these problems with the proper use of salt or, in areas with alkaline
water, by adding a very small amount of a mild acid to the water. Various
dough conditioners, buffers, and improvers that can correct these conditions
are available from bakers’ suppliers.Their use should be determined by local
water conditions.
The richness of the dough must also be considered. Doughs high in fat or
sugar ferment more slowly than lean doughs.This problem can be avoided by
using a sponge instead of a straight dough.
RETARDING
Retarding means slowing the fermentation or proof of yeast doughs by
refrigeration.This may be done in regular refrigerators or in special retarders
that maintain a high humidity. If regular refrigerators are used, the product
must be covered to prevent drying and the formation of a skin.
Retarded Fermentation
Dough to be retarded in bulk is usually given partial fermentation. It is then
flattened on sheet pans, covered with plastic wrap, and placed in the retarder.
The layer of dough must not be too thick because the inside will
take too long to chill and will overferment.When needed,the dough is allowed
to warm before molding.Some doughs high in fat are made up while chilled so
they do not become too soft.
Retarded Proof
Made-up units to be retarded are made from young dough. After makeup,
they are immediately placed in the retarder.When needed, they are allowed to
warm and finish their proof, if necessary.They are then baked.
A valuable laborsaving tool for medium to large bakeshops is the retarderproofer.
As the name suggests, this equipment is a combination of
freezer/retarder and proofer, with thermostats for both functions and with
timers to automate the process.For example,the baker can make up a batch of
rolls in the afternoon or evening and place them in the retarder-proofer with
the controls set for retarding or freezing. The baker sets the timer for the
proper hour the following morning.The machine automatically begins to raise
the temperature, proofing the rolls so they are ready to bake in time for
breakfast.