Duke PFB-2 Installation Manual

MODEL PFB PROOFER BASE

Installation, Operation, Parts &

Service Manual

319558E

CONTENTS

Page

SPECIFICATIONS 3

GENERAL PROOFING INFORMATION 3-4

FROZEN DOUGH - PROBLEMS, CAUSES & REMEDIES
LACK OF VOLUME 5
TOP MUCH VOLUME 5

CRUST COLOR TOO PALE 5
CRUST COLOR TOO DARK 6
CRUST TOO THICK 6
POOR CRUMB TEXTURE (CRUMBLY) 6
STREAKING OR SPOTTING ON CRUST (WHITE) 6
STREAKING OR SPOTTING ON CRUST (DARK) 6

DOUGH AGE AND CHARACTERISTICS
YOUNG DOUGH (UNDERPROOFED) 7

PROPERLY PROOFED 7
GENERAL COMMENTS 7

OLD DOUGH (OVERPROOFED) 7

DIAGNOSTICS 8

REPLACEMENT PARTS 9

BAKING CENTER CONTROLS 10

WIRING DIAGRAM 11

NOTICE:

Please supply the Model Number and the Serial Number when ordering replacement parts or
requesting service.

We recommend service by Duke Authorized Service Agencies during and after the
warranty period.

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Specifications

Power to the proofer base is supplied through a nine foot
(9') power cord, 3-wire, 14 gauge, equipped with a
NEMA 5-15 CAP grounded plug.

The master on/off switch connects to the axial fan,
thermometer transformer, (120v primary/12v secondary)
and to the controller, which has a temperature range
from 85" - 165°F.

The controller provides power to the air heat element
(10-<5 watts), and to the proofer ready light. A second
(500 watt) element used to regulate humidity in the
cabinet is controlled by an infinite switch. (The humidity
element will come on only when the air heat element is
on.) The humidity element heats a pan of water in the
bottom of the oven producing steam vapor.

A sixty minute timer controls the timed proof cycle, and
connects power to a buzzer indicating the end of the
cycle.

There are two probes within the proofer cavity. One is
connected to the controller to sense oven temperature.
The second probe is connected to the digital
thermometer to indicate oven temperature.

The axial fan located in the bottom of the oven circulates
heated air throughout the cavity. The fan runs
continuously when the main on/off switch is turned on.
Opening or closing the door has no effect on the heat or
fan controls.

General Proofing Information

Today many bakers use frozen dough products in their
operations. Frozen doughs are ready for traying,
thawing, proofing (if required), baking and finishing.
The baker bypasses mixing, dividing, make-up and
fermentation time.

temperature and humidity. Time and temperature
are easily controlled with properly maintained
equipment. Correct proofer humidity control can
only be maintained with a balance between
temperature and humidity settings.

Retarder Principles

Retarders provide a location for the frozen dough to
thaw slowly, until it reaches a state of even temperature
throughout the dough piece. Retarders protect the
dough from the unequal thawing caused by excessively
warm locations. The best retarders are designed to
promote a controlled, cool, slightly moist environment.
To eliminate moisture loss and crusting it is often still
appropriate to cover the entire pan of trayed product
with a heavy plastic bag.

NOTE: Condensation can cause thin, close fitting
plastic bags (like trash bags) to stick to the dough. This
often creates damaged surfaces when the plastic is pulled
free. Baking supply houses carry zippered "elephant
bags" specifically for the retarding process.

By keeping the dough between 33° - 40°F the yeast
activity in the dough is minimal, yet limited
fermentation does occur improving product flavor and
dough handling characteristics. Doughs held in the
retarder for over 48 hours often will develop strong
"sour" aromas and flavors, and if baked, will result in
inferior crumb texture and shelf life. Follow and
understand the practices outlined on the following pages
when retarding your frozen product:

1. Maintain temperature between 33" - 40°F

2. Avoid formation of crust or skin on dough pieces

3. Retard 12-16 hours (overnight)

4. Do not over-retard product (sour product)

Handling Frozen Dough

Frozen dough must be kept at a temperature of -10°F
with minimal fluctuations to prevent product damage. Be
sure to rotate your inventory so that the first product
stocked is the first product to be used.

Frozen dough is affected by three factors: Time,

5. Longer retards will require shorter proof times.

6. Fermentation begins

Proofer Operation

For the best results in a frozen dough operation, a
relative humidity of 70% - 75% is desirable, with a
temperature between 90° - 110°F. The humidity and
temperatures settings will vary depending on the
strength and kind of dough to be proofed.

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Larger pieces of dough should be proofed at a lower
temperature while smaller pieces are proofed at a higher
temperature.

Basic yeast dough should be at room temperature when it
is placed in the proofer. Placing retarded dough (directly
from the walk-in or refrigerator) into the proofer cabinet
will often result in excessive build up of condensation on
the surface of the dough. This may lead to crust
imperfections (spotting and streaking) and blistering. In
severe cases this may often result in total collapse of the
baked product after removal from the oven.

It is important to stage your retarded product into the
proofer to avoid "overproofing". For optimal results the
product must be baked immediately after the proofing
process.

The majority of yeast-raised products can be proofed
successfully between 90° - HOT and 70% - 75% relative
humidity. The quality of your final product will depend
on the initial product quality and handling from the
freezer to the oven.

Proofing Bagels

The proofing process allows the bagels to warm up and
to expand slightly before they are boiled. Bagels which
are not proofed sufficiently, may not rise to the surface
when they are boiled. However, overproofed bagels will
tend to collapse after boiling and before they are placed
in the oven.

Optimum temperatures and times will vary for various
bagel formulations. All bagels should be proofed at a
low relative humidity (65% - 75% R.H.).

Bagels which have been held overnight in a retarder or
for a short time in a freezer are usually allowed to proof
at lower temperatures (86° - 90°F) than bagels processed
without interruption. Continuously produced bagels are
generally proofed at 104°-110°F.

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