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RICHARD J. LANZA 
AND 

ROBERT V. DECAREAU 


■ Pi'?GVtD FOR 
3UC RELEASE; 



UNITED STATES ARMY NATICK 
RESEARCH 8c DEVELOPMENT CENTER 
NATICK, MASSACHUSETTS 01760 



FOOD ENGINEERING LABORATORY 









Approved for public release; distribution unlimited. 

Citation of trade names in this report does not 
constitute an official indorsement or approved of the 
use of such items. 

Destroy this report when no longer needed. Do not 
return it tc the originator. 




ECURITV CLASSIFICATION OF THIS PAGE flWian Data Entered) 


| REPORT DOCUMENTATION PAGE 

READ INSTRUCTIONS 

BEFORE COMPLETING FORM 


3. RECIPIENT’S CATALOG NUMBER 

is' 

4. TITLE (and Subtitle) 

AN AUTOMATED FIELD BAKERY SYSTEM FOR BREAD 

S. TYPE OF REPORT S PERIOD COVERED 

Final Report 

6. PERFORMING ORG. REPORT NUMBER 

7. AUTHORO) 

Richard J. Lanza and Robert V. Decareau 

8. CONTRACT OR GRANT NUMBERf*) 

N/A 

9. PERFORMING ORGANIZATION NAME AND ADDRESS 

US Army Natick Research & Development Laboratories 
Natick, MA 01760 

10. PROGRAM ELEMENT. PROJECT. TASK 
AREA 8 WORK UNIT NUMBERS 

1G263747D610-01 

II. CONTROLLING OFFICE NAME AND ADDRESS 

Food Sys. Equip. Div., Food Engineering Lab 

US Army Natick Research & Development Laboratories 

Kansas St.. Natick. MA 01760 

12. REPORT DATE 

October 1983 

13. NUMBER OF PAGES 

50 

14. MONITORING AGENCY NAME A AOORESSfi/ different from Controlling Office) 

ts. SECURITY CLASS, (of thta report) 

Unclassified 

15a. DECLASSIFICATION/DOWN GRADING 
SCHEDULE 


U. DISTRIBUTION STATEMENT (aI IMe Report) 


Approval for public release; distribution unlimited 


17. DISTRIBUTION STATEMENT (o I (ha mb a tract antarad in Block 20, II different from Raport) 


•a. supplementary notes 


<S. KEY WOROS (Continue on rararaa a/da II n ace a aery and Identity by block ntmbar) 

BREAD FIELO CONDITIONS DEPANNING 

BAKERY SYSTEM BAKING COOLING 

AUTOMATION SLICING COST(S) 

AUTOMATED BAKERY SYSTEM BAGGING 

20. ABSTRACT fCwtteM •>» mvitm tt nmaamam y mad Identity by block numbor; 

> 

The Army needs a field bakery system that can produce bread of consistent quality with 
less labor and with less skill than is required by the present M-1945 Mobile Bakery Plant 
system. This report describes the testing of a continuous, automated bakery system based 
on commercial practice but designed for operations under field conditions. The basic automated 
elements of the system are; continuous dough making and panning; continuous proofing and 
baking; depanning; cooling; slicing; and bagging. All elements are interconnected so that the 


00 I JA»TV» 1473 EDITION or » MOV BS IS OBSOLETE UNCLASSIFIED 


SECURITY CLASSIFICATION OF THIS PACE (Eton Data Bntarad) 




































20. Abstract (cont'd) 

;only labor in the process is that required to keep the ingredient hoppers filled and to handle 
the individual bagged loaves of bread at the end of the process. 

Results demonstrated the feasibility of this concept and, indicated a substantial reduction 
in labor over the current system. The cost per pound of bread based on equipment, vehicles, 
personnel, and fuel is almost six cents per pound less than the current system. y 

This work was carried out under Project 1G263747D610, Task 01. 



UNCLASSIFIED 


SKCURITY CLASSIFICATION OF THIS FAOEfW>»o Dmtm Bnfrnd) 



















SUMMARY 


A feasibility model for an automated bread bakery was developed in response to an Army 
requirement for a field bakery to replace the aging M—1945, Mobile Bakery Plant. Named 
the Automated Bakery System (ABS), the bakery demonstrated to be able to make, proof 
and bake bread dough, continuously, at a rate of approximately 850 lbs of dough per hour. 
Depanning, cooling, slicing, and bagging capabilities were also provided so that, with the 
exception of labor to fill the ingredient hoppers and box the finished product, only monitoring 
labor was required. 

I 

The entire system was housed in a series of International Standard Organization (ISO) 
containers (8' x 8' x 20') for arrangement onsite into the functional bakery. Cost estimates 
v based on equipment cost, fuel and labor indicate that the cost of the finished product would 

be at least four cents per pound less than the bread produced by the M—1945 Bakery Plant. 



DTIC 

ELECT^p 


JAN 9 1984 .* 


D 




i 









PREFACE 


In 1968 a study on bread making techniques, was initiated by the Food Systems Equipment 
Division, Food Engineering Laboratory, to investigate the feasibility of an automated, mobile, 
field bread-making system utilizing new techniques. Among the techniques examined were 
a gas injection proofing system, vacuum proofing and microwave proofing. The gas injection 
approach was subsequently discarded because commercial equipment never became available. 
Vacuum proofing was evaluated on a small scale; however, this method must be combined 
with the baking step otherwise the product will collapse. Microwave proofing and baking were 
successfully accomplished in standard metal loaf pans but the technique was discarded because, 
at the time it was too costly to pursue. 

Studies of forced convection baking were also carried out and it was shown that one-pound 
loaves could be baked in about 15 to 20 minutes. To pursue these studies and develop a 
continuous bread-making system, two continuous-roll baking ovens from an earlier project were 
modified: one became a continuous proofing cabinet and the other a continuous, forced-air 
convection oven. The conveying means were adapted to carry one-pound loaf pans. Together 
with continuous dough-making machinery, a total bread-making process of about one hour 
was demonstrated. It became clear that a continuous baking system from raw ingredients 
to sliced, bagged bread could be developed for field use in which the components in individual 
shelters, van or shipping containers could be assembled on site. 

This information came to the attention of The Army Chief of Staff for Force Development 
who requested a review of the need for field bakery equipment. The Combat Development 
Command (CDC) subsequently, concluded in 1972 that the M—1945 Mobile Bakery Plant 
satisfactorily met current requirements, but added that major product improvement of the 
bakery equipment and process will be needed in the future. Among suggestions listed were: 
use of premixes, the vertical cutter mixer (VCM), strapped loaf pans, water chilling equipment 
and forced convection baking. Accordingly, CDC was to prepare a Required Operational 
Capability (ROC) for the M—1945 product improvement. CDC also recommended continuation 
of the in-house exploratory development of a new bakery system. 

This study was funded under Project Number 1 L26374D61001006 and DOD requirement 
JSR AM6-1. 

Because the application of the Automated Bakery System is in United States Military 
Installations only. United States customary units, not metric, are used throughout this paper. 

The authors gratefully acknowledge the assistance over the years of the following NLABS 
individuals: Dennis Crockett, Joseph Doyle, Domingos Teixeira, John Caya, and Michael 
Damiano of the Prototype Shop; Henry Russell, Linnae Hallberg, John Swift, and Angelo Testa 
of the Food Technology Division; and George Alexander, Richard Bernazzani, Robert Buffone, 
Dominic Bumbaca, Harry Dostourian, Fred Fillo, Douglas Haigh, Francis Mullen, Christopher 
Rees, and Vincent Ricardi of the Food Systems Equipment Division. Inevitably in attempting 
to acknowledge the assistance of so many, some names may be inadvertently left out. The 
assistance of everyone who participated in any way in the evaluation is sincerely appreciated. 


3 






TABLE OF CONTENTS 


Summary 

Preface 

List of Illustrations 
Introduction 

Automatic Bakery System 

Operational Considerations 

Results of Production Testing 

Discussion 

Conclusions 

Recommendations 

Appendix A — Analysis in Support of Automated Field Bakery System 

Appendix B — Production Costs of Field Bakery Systems 

Appendix C — Instruction Manual-Operation of Continuous Dough 

Making and Dough Depositing Machine with Pan Indexing 









LISTS OF ILLUSTRATIONS 


Page 

Figure 

1 Layout of the Automated Bakery System 12 

2 View of continuous dough maker showing control panel (A). 14 

Separate yeast brew kettle components (B) shown at the right. 

3 This view of the dough maker shows the dough developer (A), 15 

divider and panner (B) and the developer drive motor (C). 

4 This view from the side opposite Figure 3 shows the shortening 15 

tank (A), dry ingredient hopper (B), premixer or incorporator (C), 

and lines (0) from the dough pump (not visible, but located below 
the incorporator), to the dough developer (E), and 
divider/panner (F). 

5 Artist concept of continuous proofer (A) and bake oven (B). Bread 17 

from the dough maker enters proofer at the left. 

6 A look inside the proofer at the point where bread transfers to 15 

the bake oven. 


7 An exterior view of the bake oven with the burner side open. 19 

8 Bread as it exits from the oven. Photograph was taken before 21 

automatic depanning equipment was received. 

9 Layout of the dough-making equipment and relationship to the 25 

proofer. 

10 Effect of the developer speed (rpm) on the shape of the bread loaf. 28 

Table * 

1 Options for Providing Bread in the field 9 

2 Comparison of Production Costs of Three Field Bread Systems ($/lb) 11 

3 White and Rye Dough Formulas 26 

4 Automated Bakery System Processing Times for Each Step 29 

5 Automated Bakery System Representative Operating Conditions 30 

6 Automated Bakery System Staffing Based on Operating Experience 31 


6 










AN AUTOMATED FIELD BAKERY SYSTEM FOR BREAD 


INTRODUCTION 


The M— 1945 System 

All rations used by the Army in the field specify bread and/or bread products as 
components of the daily menu. Present equipment for field-baked bread is the M—1945 Mobile 
Bakery Plant (LIN M18647). The M-1945 Mobile Bakery Plant consists of a machinery and 
make-up trailer, three trailer ovens, and associated diesel generators, water tanks and tentage. 
It is an entirely manual system with the exception of mixing, dividing and forming of the 
dough. Two 486-pound batches of dough can be made per hour. Each batch is transferred 
to a dough trough for approximately two hours fermentation; after which the dough is divided, 
shaped, panned (six — 36 oz pieces per pan) and placed in a proofing cabinet. Proofing takes 
about one hour. Pans are then transferred to the oven for approximately one hour for baking. 
The bread is then depanned onto cooling racks and later bagged (one six-loaf cluster per bag). 

Although no firm data on the Mobile Bakery Plants production capability over prolonged 
periods of time exist, the system's operating manual (FM 10—22) indicates a capacity of 
approximately 11,000 pounds of bread in a 20-hour period. There is some variability in product 
quality with the M—1945 system(because of the variability in product quality with the M—1945 
system) because of the variation in the skills of bakery personnel working with the several 
bread formulas and because of variations in ambient temperature and humidity, which influence 
the process, in many geographical areas. Contributing to the lack of skilled bakery personnel 
was the elimination of the Army's Baker Military Occupational Specialty. 

The M—1945 equipment is not in keeping with the current state-of-the-art. Commercial 
bakery equipment today produces bread and bread products of consistent quality and at 
production rates of 14,000 pounds/hour or more. 

The Army in the field has an operational need for an improved bakery system that can 
produce bread of consistent quality using less skilled labor. 

The M—1945 bakery system is more than 30 years old and spare parts are procurable 
at a high cost. A Product Improvement Proposal (PIP) to upgrade this system was prepared 
in 1971 as a first approach to fielding an improved field bakery system. Analysis indicated 
that the PIP would neither be cost effective nor eliminate the disadvantages of a low production 
rate and a high labor requirement. 

Product Improvement of the M—1945 Bakery Plant 

Studies were carried out in 1974 along the lines suggested by CDC; i.e., use of the vertical 
cutter mixer (VCM), strapped pans and forced convection baking. The VCM did produce a 
satisfactory product. There was, however, some concern about heat build-up in the mixing 
bowl, which might affect subsequent mixes and which might require a jacketed cooling system. 
Variations in mixing time require considerable skill in judging when the dough is ready. The 
capacity of the VCM is only one third that of the current M—1945 mixer. Space does not 







permit placing more than one VCM on the machinery trailer, thus heat build-up becomes serious 
because the single mixer must operate almost continuously. 

Strapped pans do result in some reduction in the proofing and baking time, but not enough 
to eliminate a single oven. Proof time for two-pound loaves was found to be about 55 minutes 
and forced convection baking about 40 minutes. The use of strapped pans results in increased 
handling because one-third more pans (162 vs 108) are required to obtain the same production 
rate. If one-pound loaves were to be produced, then it would be necessary to handle three 
times as many pans (324 vs. 108). The proof time for one-pound loaves is about 50 minutes 
and the bake time is less than 25 minutes so that theoretically two batches could be baked 
per oven per hour. However, because of the long proof time and the larger number of pans 
which must be used, six proof boxes are needed to go along with the three ovens. The 
dimensions of the strapped one-pound loaf pans are not much smaller than the standard loaf 
pans so that only two additional pans can be placed in the ovens. Because any change to 
smaller loaves only increases the labor requirement, it was felt that a comparison based on 
two-pound strapped loaf pans was the best compromise. 

The major advantage to be gained from the modifications tested in this feasibility study 
is the elimination of the fermentation step and associated equipment (dough troughs and 
overhead track). Thus the use of the VCM and premixes means that the first loaf of bread 
is out of the oven in under two hours and subsequent batches about every ten minutes thereafter. 
Allowing one hour for cooling, slicing and bagging, the first 72 two-pound loaves are ready 
for issue in under three hours. 

Labor is the major factor that will be affected by these modifications. Although this 
can be determined accurately only from actual operations, the additional mixing operations, 
pan handling into and out of the proofer and into and out of the ovens, and the slicing and 
bagging operations require a minimum of six men per platoon. Other cost elements include 
the slicing and bagging equipment and redesign needed to permit containerization of the 
equipment for shipping, and the forced convection oven design. 

Other Systems 

Two other approaches were taken to define a specific method for furnishing bread in 
the field. 

The first approach analyzed every method available to supply bread for the field soldier. 
Table 1 summarizes the updated 1978 cost level results. Details covering cost levels that 
prevailed in 1975 are provided in Appendix A. The data indicate that the M—1945 field 
bakery was the most economical approach. 

The second approach continued the research and development work unit initiated in 1968 
entitled, "Investigation of Unique Bread Making Techniques." 

Because the M—1945 system requires approximately two hours for fermentation and an 
hour for pan proofing, a number of approaches that shorten the dough proofing were examined. 
Of these approaches, gas injection, vacuum and microwwe proofing were determined to need 















Options for Providing 


Basic 


Point of Use 

Form of 

Baking 

Cost 

Bread 

Location 

(S/lb) 

Fresh 

CONUS w/ 

1.00 


air transport 

1.28 


Field Kitchens 

0.51 


Field Bakery 

0.25 

Frozen 

CONUS 

0.79 

Whole 

Frozen 

Field Kitchen 

0.59 

Dough 


Field Bakery 

0.50 

Frozen 

Field Kitchen 

0.78 

Brown & 

Serve 

Field Bakery 

0.76 

Shelf 

CONUS 

1.27 

Stal,„ 

(Canned or 

Pouch) 


Bread in the Field 

Comments 

Need committed air transportation; 
specific cost depends on aircraft used. 

Based on 5 man-hours labor/100 lbs bread. 

M—1945 Baking plant 

Needs freezer storage 

Needs freezer storage 

Needs freezer storage 

Needs freezer storage 

Needs freezer storage 

Has yet to be completely and successfully 
developed. 

















extended developmental effort. Microwave proofing in metal bread pans demonstrated that 
the quality of the baked bread compared favorably with the controls, but the cost of such 
a system ruled out this approach. The dough used in this proofing study was made with 
a laboratory continuous dough maker (AMFIo300, manufactured by American Machine and 
Foundry Co.) and could be immediately panned and proofed. No intermediate fermentation 
step was required. Continuous dough making seemed desirable because of the dough maker's 
simplicity and consistency in producing a good quality product. 

Two continuous roll baking ovens, used in an earlier project, were modified: one into 
a cabinet for dough proofing and the other as an oven for continuous forced convection baking. 
The conveyors were adapted to carry one pound loaf bread pans. The laboratory continuous 
dough making equipment, the AMF!o300, and the modified ovens were capable of reducing 
the total bread-making process to about one hour. 

To confirm the cost effectiveness of the continuous and optimally mechanized approach, 
a cost analysis was carried out based on a 20-year life cycle. The updated 1980 cost results 
are given in Table 2, with details presented in Appendix B. It should be noted that the 
continuous system, referred to as the Automated Baking System (ABS), and the M—19451 
both included slicing and bagging equipment that was not a part of the basic M-1945 Bakery 
Plant. 

To determine the magnitude of labor reduction possible with the continuous system, 
production was scaled up to field bakery levels. Procurement action was initiated to purchase 
a continuous dough maker/pan depositor to operate at 800 pounds/hour. A contract was 
awarded in 1973. The equipment was delivered in 1975. Procurement action was initiated 
in 1974 for design and fabrication of the continuous proofer and oven to mate with the dough 
maker. 

The initial concept for mounting the components of the ABS in trailer vans was discarded 
in favor of mounting them in a container system. This approach is described in the Letter 
of Agreement (LOA) that was completed and approved April 1977. The LOA emphasized 
reduction in manpower, reduced need for skilled bakers, environmental protection, and 
incorporation of slicing and bagging equipment. 

In keeping with these requirements, funds were made available to have the proofing and 
baking ovens housed in containers and to procure containerized equipment to perform the 
depanning/cooling and slicing/bagging operations. The general arrangement of the ABS is shown 
in Figure 1. 

The Draft Outline Development Plan for the ABS was written in 1979. Due to delays 
in receipt of the depanner/cooler and slicing/bagging units from the contractor, development 
testing of the initial prototype, originally scheduled for 2Q80, was postponed to 4Q80. The 
units still had not arrived by 4Q80. Through an agreement with Testing Commands, testing 
of available components began at Natick Laboratories. Eventually, the equipment was delivered 
in March 1981. 

Duiing the delay, TRADOC's position had changed and a need for a greater degree of 
field mobility of the units was expressed. A special In-Process Review (IPR) on the ABS 


10 








Comparison of Production Costs of Three Field Bread Systems ($/lb) 

M—1945 M—1945 Automated 

Field Bakery Plant Improved* Bakery System 

Equipment & Vehicles $0.00544 0.00470 $0.00789 

Fuel 0.00641 0.01281 0.01282 

Personnel 0.09587 0.08760 0.04343 

Total $0.10772 $0.10512 $0.06414 

Incorporation of vertical cutter mixer, strapped pans, power unit and slicing and bagging 
operation. 

•• 

Vehicle life assumed as 5 years; baking equipment life assumed as 20 years. 



Figure 1. Layout of the Automated Bakery System 





























was requested and held March 18, 1981. The I PR concluded that the ABS, though responsive 
to the LOA, was no longer valid. In order to accumulate valuable data that might still prove 
useful in development of a battlefield bakery system, a continuation of testing was 
recommended. 

AUTOMATED BAKERY SYSTEM 

Dough Maker/Pan Depositor 

The continuous dough maker/depositor is shown in Figures 2, 3, and 4. This unit of 
the system performs the following functions: metering and mixing flour and other dry 
ingredients, shortening and yeast brew; mechanically developing the mixture into a properly 
textured viscous dough; and depositing measured amounts into sets of strapped bread pans. 

Variable-speed, belt-driven pumps deliver the shortening and yeast brew to the premixer. 
The flour mixture is delivered by a helical screw driven by a variable-speed motor. The premixer 
is a covered, stainless steel trough with twin auger impellers that mix the ingredients and deliver 
the mixture to the dough pump. The dough pump is variable speed, belt driven, and delivers 
the dough mixture to the developer. The unit has two star-shaped impellers (four stainless 
steel lobes per impeller) built into a machined stainless steel housing that blends, kneads, and 
develops the dough for pan proofing. Under pressure of the dough pump that feeds it, the 
developer delivers dough continuously to the pan depositor section of the developer, which 
by means of a pair of cam actuated jaws that cut off precise quantities of dough and, aided 
by gravity, delivers the dough pieces a few inches below to indexing bread pans on a conveyor. 

Proofing Oven 

A view of the proofing oven is shown in Figure 5. It consists of two levels of powered 
roller conveyors housed in an 8' x 8' x 20' container. The double tier conveyors, which 
are alternately fed the baking pans provide adequate proofing space for the maximum output 
of the dough maker/pan depositor. Known for their ruggedness and stability, roller conveyors 
were selected as suitable components for movable field equipment. The strapped dough pans 
are alternately delivered three at a time to the two levels of the proofer by an hydraulically 
actuated, interconnecting feed conveyor. A pusher bar actuated by three micro switches pushes 
the three strapped dough pans at each level into the proofer. The effectiveness of the proofer 
can be seen in Figure 6. 

The proofing oven has its own fuel-fired, powered burner for providing a suitable proofing 
temperature with some additional heat being diverted from the oven. Humidity control was 
provided by piping steam into the oven dirough a series of manifolded nozzles. 

Baking Oven 

The baking oven (Figure 7) also has the double tier, powered roller conveyor design. The 
conveyors are aligned with those in the proofer. The space between the two is bridged by 
a foldable connecting conveyor section that is physically a part of the proofer oven during 
transport. 

































Figure 4. This view from the side opposite Figure 3 shows the shortening tank (A), dry 
ingredient hopper (B), premixer or incorporator (C), and lines (D) from the 
dough pump (not visible, but located below the incorporator), to the dough 
developer (E), and divider/panner (F). 



Figure 5. Artist concept of (ontinuous proofer (A) and bake oven (B). Bread from the 
dough maker enters proofer at the left. 







































Heat for the oven is supplied by three fuel-fired, powered burners capable of burning 
any of four fuels: JP—4, kerosene, diesel, or gasoline. Each burner can be regulated 
independently to provide the proper oven temperature. Using three burners provides a degree 
of reliability. If one or two malfunction, some baking can still be performed. The speed 
of the oven is greater than the proofer to help prevent jamming in the oven. 


Discharging from the oven includes a timed transfer of a row of pans to a periodically 
raised and lowered belt conveyor operating at right angles to the oven conveyor. Fully baked 
bread is shown (Figure 8) exiting from the oven. This photograph was taken prior to installing 
the transfer mechanism. 



Figure 8. Bread as it exits from the oven. Photograph was taken before automatic 
depanning equipment was received. 


Depanner/Cooler 

The depanner/cooler is housed in a one-sided expandable container. The expandable side 
contains the accumulating conveyor, which receives the pans of bread from the oven and conveys 
them to the depanner mechanism. 

Depanning is accomplished by elevating two strapped pans at a time to a position where 
flexible, suction appendages, connected to a vacuum system, engage eight loaves at a time. 
The pans are lowered and returned by conveyor to the dough maker/pan depositor unit. The 
loaves, conveyed over to the cooling conveyor, are released and conveyed to the end of each 


16 
















level where they slide onto an indexing tray before being transferred to the next lower level 
moving in the reverse direction. The bread loaves progressively move down the six levels of 
this cooling conveyor and at the end of the final pass are indexed by a pusher bar onto another 
conveyor, which carries them to the slicer/bagger section. 

Sicer/Bagger 

In this final operation, the individual loaves of bread are sliced and/or bagged. The shelter 
for this operation is a one-side expandable container. Bread from the cooling section is conveyed 
into the slicer/bagger shelter directly to the slicer. The slicer is a modified commercial band 
slicer. The modification was necessary to reduce the overall height of the slicer so that it 
would fit into the container. Both the slicer and the bagger are wheel-mounted allowing the 
slicer to be moved into or out of position, thus providing the option of delivering sliced or 
unsliced, bagged, bread. This operation is the first place where anyone handles the product 
since the raw ingredients were placed into the brew kettles, shortening pan, and dry materials 
hopper. 

Support Module 

This sixth component of the ABS was designed to house the two diesel electric generators 
that provide the power to operate the system and a small repair shop complete with tools, 
parts, and hardware to perform operational maintenance functions. Built according to 
International Standard Organization (ISO) dimensions for containers, i.e., 8' x 8' 20', it is 
essentially the ISO frame with mounted and exposed diesel generators, and a closed area, each 
occupying approximately half the frame. 














OPERATIONAL CONSIDERATIONS 


Dough Maker/Pan Depositor 

The operation of the unit is described as follows: the basic ingredients - dough mix, 
yeast brew, and shortening, are delivered from the dry ingredient mix hopper, brew tanks, 
and shortening tanks at predetermined rates to a premixer (incorporator) located just below 
and in front of the shortening tank (Figure 4). When the dough level nears the top of the 
incorporator, the dough pump is turned on and the developer motor is set at maximum 
revolutions per minute. When the dough begins to flow through the developer by-pass, a 
three-way valve in the line is turned, diverting the dough into the developer. After approximately 
30 seconds, the divider/panner drive motor is turned on and strapped pans begin indexing 
under the depositor. Properly developed dough will usually begin depositing after approximately 
a dozen pans have been filled. At this point, it should be necessary to keep only the individual 
component hoppers and tanks filled with ingredients. 

Although the dough maker/pan depositor has performed essentially without a flaw, there 
are some aspects of its design that should be changed in any new production arrangement. 
A one-side expandable ISO shelter has been obtained for this unit but the unit has not yet 
been installed in the shelter. 

In addition to installing the dough maker/pan depositor, matters to be considered in 
outfitting the shelter include: 

(1) A water heater to provide controlled-temperature water to the yeast brew tanks and 
hot water for sanitation purposes; 

(2) A sink for cleaning components of the dough maker; 

(3) A heat exchanger to control brew tank temperature during operation at extreme 
temperatures; 

(4) Storage for spare parts, tools, etc. 

Changes that should be made in the design of the dough maker include the following: 

(1) Feed Hopper. In case pre-prepared mix is not available, the dry ingredient hopper 
should contain a system that can mix the basic dry ingredients. One suggestion is to mount 
a ribbon mixer above the feed trough with a sliding partition or gate between the two. The 
trough should be enlarged to hold enough dry ingredients for a 20-minute operation, while 
the ribbon mixer is being loaded and operated to prepare a batch of mix. Under normal 
conditions, using a pre-prepared mix, the mixer partition is left open and the mixer operated 
to prevent bridging of the dry ingredients. Alternatively, many of the dry ingredients could 
be fed in with the yeast brew. To provide sufficient space to load the hopper from above, 
the design should provide sufficient headspace to accommodate a container eight feet high. 

(2) Incorporator. Since clean-up during shutdown is very difficult and time consuming, 
the design of this premixer is problematic. A preferred arrangement would be to include the 




















capability for removing the impeller so that it can be cleaned in the sink. Then, the mixer 
hopper can be easily cleaned out. 

(3) Dough Pump. The location of the drive motor to the divider panner hinders the 
accessibility of the dough pump for cleaning. A larger drive belt would provide more working 
space. 

(4) Floor Drainage. During clean-up, water accumulates on the floor and under the 
equipment. Some floor drains and grating should be provided. Grating should be easily removed 
to clean underneath. 

(5) Materiel Handling Equipment (MHE). Some method should be provided to facilitate 
emptying bags of ingredients into the dry ingredient hopper. The difficulty at this stage is 
compounded by the lack of headspace. 

Proofing Oven 

Although the proofing oven performed satisfactorily, some design changes should be made. 
Humidity control by steam injection is effective but presents both maintenance as well as 
operational problems. A much simpler, heated water pan approach, originally built into the 
system, should be perfected. 

In addition, the location of drive chains inside the proofer makes lubrication difficult. 

Baking Oven 

The two major deficiencies in this unit are (1) the drive chain's location inside the oven 
that makes maintenance and lubrication difficult, and (2) controlling oven temperature. 

When the oven is operating at high temperatures, the drive chain at its present interior 
location is very difficult to lubricate. To relocate the drive mechanism outside the oven shell, 
a complete redesign is necessary. If a break should occur, it would be possible to repair the 
chain without having to shut down and cool the oven. 

All petroleum-based lubricants charred, hardened, and coated the bearings, making them 
unacceptable. The only effective lubricant was a water-based graphite. The disadvantage of 
this lubricant was the lack of protection during long periods of inactivity. 

Upper and lower oven temperature differences need to be corrected. The lower oven 
provides excessive heat to the bread surface and, as a result, often the crusts are charred while 
the loaf interiors may be underbaked. 

The original oven design had heated air circulating through ducts. The hottest air was 
directed to the bottom of the upper oven while the opposite effect was planned for the lower 
oven. In order to balance temperatures and obtain uniform baking, a damper system in the 
ducts was provided to divert the air flow. The traditional and successful baking approach 
requires intensive heating from die bottom. The ABS oven results confirmed this approach. 


19 








The upper oven yielded an excellently browned and uniformly baked loaf; the lower oven 
frequently produced a charred and partially baked loaf. Adjustments to the damper system 
and minor ducting changes insufficiently reduced temperature variations. 

Depen ner/Cooler 

The general performance of this unit must be considered unsatisfactory. The major 
components, the mechanism that places the pans from the two levels of the oven to a single 
level, the accumulating conveyor, and the depanner work exceptionally well. However, the 
cooling tier conveyor has numerous problems. The major deficiencies are in the mechanism 
that lowers the bread from tier to tier. Any change in bread consistency can create loaves 
that stick or hang up on the wire conveyor or slide eratically on the lowering shelves. One 
stuck loaf results in a chain reaction damaging many loaves and interrupting the operational 
system. Simpler and lighter conveyor cooling systems have been identified to replace the existing 
system. 

Slicer/Bagger 

There are a number of much simpler, lighter, and less costly bagging machines that can 
replace the high-speed machine selected. Also, a smaller, less costly slicer is available that 
would better suit the requirements of the ABS. 

Support Module 

Although the diesel generators and the repair shop were mounted on the ISO frame, this 
part of the system was not tested. 

RESULTS OF PRODUCTION TESTING 

The arrangement of the equipment for dough making is shown in Figure 9. Initially, 
a one-side expandable hard shelter (8' x 8' 20') was presumed to provide adequate space to 
house the dough making operation. To expedite testing, an expanded 8' x 8' x 20' shelter 
was marked out on the floor of the laboratory and an open wall of 2" x 3" lumber was 
erected to simulate the confines of this shelter. With the exception of the Support Module, 
all other elements of the ABS were assembled inside, as shown in Figure 1. 

The start-up procedure is described in detail in Appendix C. The formulas used are given 
in Table 3. Based on the white bread formula, a quantity of bread dough mix (in 50 pound 
bags), was purchased from a local supplier. The feed rate of the various components of the 
dough are shown at the bottom of Table 3. Feed rates are calibrated by dispensing quantities 
of mix, brew, and shortening into tared containers for a set period of time, usually 30 seconds 
to one minute, then reweighing the container. Delivery rate changes are made by adjusting 
drive motor speeds or pump speeds until the required rates are obtained. Once feed rates 
have been set, they will remain reasonably constant but should be checked periodically, possibly, 
once, a day. 


20 



















Tabic 3 


White and Rye Dough Formulas 


Whits Bread 


Rye Bread 


White fiour 

- 208.50 lb 

White hour 

- 190.00 lb 

Sugar 

10.56 lb 

White rye 

47.50 lb 

Salt 

4.125 lb 

Salt 

5.00 lb 

NFDM 

6.56 lb 

Sugar 

6.00 lb 

Yeast food 

1.00 



Do-contrql 

1.63 




232.375 lb 


248.50 lb 

Brew 


Brew 


Water 

160.00 lb 

Water 

156.75 lb 

Yeast 

5.25 lb 

Yeast 

6.00 lb 

Mix 

23.50 lb 

Mix 

24.85 1b 

Bromate 

2 Tablets 

Bromate 

2 Tablets 

Shortening 

6.03 lb 

Shortening 

6.00 lb 



Feed Rates 


Dry mix 

6.96 Ib/min 


7.455 Ib/min 

Brew 

6.30 Ib/min 


6.25 Ib/min 

Shortening 

90 g/min 


91 g/min 


21 








.v.-v 


‘-'A‘v\Vk 


jeLj 













Figure 9. Layout of the dough-making equipment and relationship to the proofer. 

Because bread loaves exiting the oven often had collapsed side walls, giving a keyhole-shaped 
cross section, a number of runs were made in which the developer speed was varied. Apparently, 
fully developed dough could be produced at almost any developer speed from 100 to 200 rpm. 
In most runs, a developer speed of 150 rpm was used. However, after several closely monitored 
runs, evidence indicated that only at 200 rpm, the upper speed limit of the developer, could 
straight side-walled loaves of bread be produced consistently (Figure 10). This developer speed 
yielded a very relaxed dough. The lower speeds produced a developed, but recognizably stiffer 
dough that proofed adequately. However, when this stiff dough entered the oven, the high 
temperature caused a rapid development of the dough in the pan resulting in collapsed sides. 
Commercial baking operations allow the dough to relax after panning so that this distortion 
does not occur during baking. The ABS process does not provide time or space for the relaxation 
step; therefore, a more relaxed dough must be produced by higher developer speeds. 

















Figure 10. Effect of the developer speed (rpm) on the shape of the bread loaf. 


Brew kettle operations require proper timing of batch make-up for continuous dough 
making. A 20-gallon batch is adequate for 30 minutes of dough production. If 30 minutes 
of fermentation is desired and with only two 40-gallon kettles available, no time is allowed 
for making up a second batch. Since the yeast growth creates considerable carbon dioxide 
effervescence and overflows the kettles, a 28-gallon batch of yeast brew is almost too much. 

A third kettle of the same size (40 gallons) or possibly two larger size kettles (e.g., 60 gallons) 
would be needed. 

Continuous runs of rye bread and white bread were carried out producing four complete 
batches without shut down. During white bread production, an attempt was made to make 
a few loaves of raisin bread by manually introducing the raisins into the incorporator. The 
developer, however, reduced the raisins to small specks, unrecognizable as raisins. { 

I 

i 

Dough production is limited to about 850 pounds of dough per hour by the speed of 
the dough pump. Since the various ingredient feed mechanisms all are operating below their 
maximum feed rates, a change in the gears that drive this pump could increase production 
to at least 1,000 pounds per hour. Also, the developer, proofer, and oven should be able 
to handle this higher volume. However, about 20% more brew kettle capacity would be required. 

The processing time for each step of the ABS operation is given in Table 4. Total time 
from start of ingredient flow to bagged product is one hour and 49.4 minutes. This compares 
to the approximately seven hours for producing bread ready for delivery by the M-1945 Bakery 
Plant. Representative operating conditions for the ABS are given in Table 5. 

Staffing considerations 

A tentative staffing requirement for the ABS is given in Table B-3. Although based 
on limited operation of the ABS components in this laboratory, it appears that the following 
personnel are essential for successful operation: 



















(1) Doughmaker operators. After start up, which takes no longer than 40 minutes, the 
doughmaker operator is free to perform other tasks such as assisting in keeping the mix hopper 
and the shortening tank filled, making up kettles of yeast brew as needed, and adding shortening 


Table 4 

Automated Bakery System Processing Times for Each Step 


Function 

Time per Function 
(Minutes) 

Cumulative Time 
(Minutes) 

Dough Mix Development 
and Panning 

4.0 

4.0 

Feed to Proofer 

0.2 

4.2 

Proofing 

35.0 

39.2 

Baking 

25.0 

64.2 

Depan and Cool 

45.0 

109.2 

Slice and Bag 

0.2 

109.4 


24 






Table 5 


Automated Bakery System 
Representative Operating Conditions 


Operating Variable 

Doughmaker: 

Dry mix feed 
Brew feed 
Shortening feed 

Loaf Panning 
(18.0 oz/loaf) 

Proofer: 

Temperature 
Relative Humidity 
Proofing time 

Oven: 

Temperature — Zone 1 
— Zone 2 
- Zone 3 


Baking Time 

Diesel fuel consumption 

Depanner/Cooler: 

Air conditioning 
Suction blower 

Slicer/Bagger: 

Bag size 

Power Module: 

60 kW generator 


Rate 


417 Ib/hr 
378 Ib/hr 
1.2 Ib/hr 

690 loaves/hr 


65-70° F 
60-80% 
35 min 


400° F 
450° F 
400° F 

28 min 
4 qal/hr 


2 ton unit 
10 HP motor 


Standard 1 lb loaf 
Fuel Consumption: 
4-6 gal/hr 


25 












to the pan greasing tank. The only other task for the doughmaker operator is to tear down 
and clean up the equipment when the baking day ends. Two persons should be more than 
adequate to operate this unit. 

(2) Packaging equipment operators. Aside from general monitoring of the various 
operations, the only other laborious task is handling the bagged loaves of bread at the end 
of the run. Two men should be able to keep up with the output of the bagging equipment. 

(3) Maintenance person. The maintenance person's responsibility would be to monitor 
proofer and oven conditions (temperature, humidity, conveyor speed), lubricate conveyor drive 
chains and motors, monitor burner unit performance during baking operations, and perform 
general maintenance on all components of the system. On the basis of actual operation of 
the ABS over several months, all bakery personnel should be trained for all positions including 
some of the simpler maintenance functions. For short runs of one to two hours it appears 
that the actual on-the-job personnel requirement during operation could be much less than 
indicated in Table B—3. The revised staffing is shown in Table 6 for a two-shift operation. 

Table 6 

Automatic Bakery System Staffing Based on 
Operating Experience 


Platoon Ldr, Lt. 1 

Platoon Sgt, E-6 1 

Shift Ldr, E—5 2 

Bakers, E-4 4 

Mechanic, E—4 2 

Heavy Truck Driver, E—4 1 

Light Truck Driver, E-3 2 


13 

DISCUSSION 

During the investigation, all elements of the ABS operated continuously with only minor 
problems that were correctable. It should be noted that this unit was a "feasibility" model. 
Any deficiencies and shortcomings identified would be corrected in any follow-on model. The 
major deficiencies and areas that require improvement have been listed in previous sections 
describing the various system components. 

In comparing the ABS with the M—1945, it is readily apparent that use of the ABS reduces 
labor and the number of skilled workers significantly. Also, there are fewer burdensome tasks. 









such as punching the fermented dough and manhandling heavy pieces of dough from the 
fermentation troughs to the dough divider. The numerous manual transfers of heavy dough 
pans into and out of the proofers and ovens are eliminated. Personnel who could be used 
more productively elsewhere are required for these tasks and there is also a degree of danger 
in handling the hot bread pans and manual depanning loaves onto cooling racks. 

The effect of this lower staffing requirement over that originally estimated (Appendix B) 
is to reduce the personnel operating costs to $0.0253/pound of bread. The total cost 
(equipment, vehicles, fuel and personnel) is reduced to $0.04424/pound of bread or almost 
six cents per pound less than the M—1945 Bakery Plant. Even tripling the equipment costs 
adds less than two cents to die cost of bread produced by the ABS. 

Some redesign is required to perfect the ABS. Specifically, the conveyor drive in the 
oven and proofer needs to be made more accessible for lubrication purposes; to obtain a more 
uniform temperature distribution in the upper and lower oven sections the heating air-ducting 
in the oven needs to be modified; and the bread cooling system needs to be simplified. None 
of the modifications is particularly difficult to accomplish. 

CONCLUSIONS 

It was demonstrated that the ABS model can produce, on a continuous basis, 850 lbs 
of bread dough or approximately 750 pounds of sliced and bagged bread each hour. White 
and rye bread were produced and it should be possible to produce whole-wheat bread without 
difficulty. 

It was also shown that the ABS requires fewer, less skilled (except for maintenance) 
personnel to produce high-quality bread, efficiently, consistently, and at less cost compared 
to the M—1945 Bakery Plant. Trained bakers are not needed, since the operation of the 
dough-making equipment can be programmed so that, once ingredient feed rates have been 
calibrated, the operation can be started and maintained simply by activating a single switch. 

RECOMMENDATIONS 

The Automated Bakery System should be given serious consideration as a replacement 
for the M—1945 Bakery Plant. 

To eliminate the deficiencies found in the feasibility model, the necessary modifications 
should be made and the system tested in the field. 









APPENDIX A 


Analysis in Support of Automated Field Bakery System 
APPENDIX B 

Production Costs of Field Bakery Systems 
APPENDIX C 

Instruction Manual - Operation of Continuous Dough Making 
and Dough Depositing Machine with Pan Indexing 
























APPENDIX A 


Analysis in Support of Automated Field Bakery System 
INTRODUCTION 

The analysis that supported and helped justify the approved Letter of Agreement for an 
Automated Bakery System, consisted basically of two phases: 

1. The initial considerations involved alternate methods for providing either ingredients, 
semi-prepared bread or prebaked bread to a theater of operations. It was assumed that fresh 
bread would not be available locally in a theater of operations. 

2. Since the results of the basic logistical findings indicated that the most economical 
technique would be the use of a field bakery, the trade-off analysis then narrowed down to 
determining the most appropriate specific design for a field bakery. In addition to an economic 
measurement, expressed as Relative Worth, design selection was governed by: 

a. Recognition that skilled bakers would be scarce in the future; 

b. The need to furnish a finer textured, "commercial-style" bread of greater 
familiarity to the current generation of soldier; 

c. Establishment of baking parameters that were compatible with the needs for 
continuous operation. 

OPTIONS FOR BREAD TO THEATER OF OPERATIONS 

Table A-1 gives the point of use costs and lists special considerations for the basic methods 
of supplying bread to the field: baked fresh from ingredients; frozen in some form at some 
stage of the process; and shelf-stable, a method yet to be satisfactorily developed. Cost factors 
for the original analysis (1975) were as follows. 

1. Base labor cost was figured as an E-3 plus 100% overhead. The base rate was 
$5.00/hour; 

2. Material costs were based on typical bread formulas with ingredient prices as listed 
in the Federal Stock Catalog; 

3. In some instances, where no data were available, a best "guesstimate” was made. 

It was assumed that the distribution and storage system could accommodate the volumes 
and the shelf life limits of each alternate. 

The figures used for the 1975 analysis were increased by seven percent per year for three 
years for inflation. Transportation costs were added, based on 





Table A-1 


Options for Providing Bread in the Field 


Basic 


Point of Use 


Form of 

Baking 

Cost 


Bread 

Location 

($/lb) 

Comments 

Fresh 

CONUS w/ 

1.00- 

Need committed air transportation; 


air transport 

1.28 

specific cost depends on aircraft used. 


Field Kitchens 

0.51 

Based on 5 man-hours labor/100 lbs bread. 


Field Bakery 

0.25 

M—1945 Baking plant 

Frozen 

CONUS 

0.79 

Needs freezer storage 

Whole 

Frozen 

Field Kitchen 

0.59 

Needs freezer storage 

Dough 


Field Bakery 

0.50 

Needs freezer storage 

Frozen 

Field Kitchen 

0.78 

Needs freezer storage 

Brown & 

Serve 

Field Bakery 

0.76 

Needs freezer storage 

Shelf 

Stable 

CONUS 

1.27 

Has yet to be completely and successfully 
developed. 

(Canned or 






















$169/40 ft 3 for perishables for 3,000 miles of sea transport, or 
$ 65.69/40 ft 3 for nonperishables during sea transport. 

FIELD BAKERIES 

Because the basic analysis pointed towards a field bakery and exploratory development 
provided a basis for considering continuous processes, a comparison was made between the 
M—1945 mobile bakery and a concept for a continuous system. Preliminary considerations 
were: 


1. A product improvement program for the M—1945 bakery was indicated to be non-cost 
effective; 

2. The addition of depanning, cooling, slicing and bagging functions to field bakery 
operation would extend shelf life while saving bakery personnel; 

3. The one half* pound per man per day issue factor was based on unsliced bread. A 
reduction in the issue factor for sliced field bread was therefore considered a strong possibility. 

Table A—2 presents costs to field an M—1945 bakery. Costs for 1978 were based on 
1975 costs multiplied by 1.22 (7% per year increase). Table A-3 presents a similar break-out 
estimated for an automated field bakery system. 

If, therefore, for a corps of 100,000 a comparison of field bakery needs is made, it would 
be: 

1. On the basis of all procurement costs assumed in first year. 

9 M—1945 bakeries per corps $4,397,760 

3 Automated field bakery systems $2,730,381 

The potential savings, on annual 

fielded basis is: $1,667,379 

2. If the major equipment items are given a 20-year useful life and vehicles are given 
a five-year life and a simple straight line amortization is assumed. 

9 M—1945 bakeries per corps $1,922,292 

3 Automated field bakery systems $ 486,246 

Potential savings per year: $1,436,046 

The decision was made to proceed with the development of an automated field bakery 
system. 


31 























Table A—2 


Cost to 

Field M—1945 Mobile Bakery System 

Major End Items 

Mixing and Makeup Trailer 


$ 83,407 

Bakery Ovens (3) 


60,932 

Proof Cabinets (3) 


11,276 

Sifting Machine 


5,725 


Subtotal 

$161,340 

Other Components 

Shelters (6) 


6,622 

Ancilliary Bakery Equipment 


75,511 

Vehicles 


49,266 

Adminstrative and Personal Equipment 

_5,928 


Subtotal, Equipment 

$298,667 

Personnel (19) (Annual) 


189,973 


Total Cost 

$488,640 





















Estimated Cost To Field the Automated Bakery System 


Dough Developer 

$ 91,500 

Proofer 

91,500 

Oven 

274,500 

Depanning-Cooling Unit 

30,500 

Slicing-Bagging Unit 

14,640 

Power and Service Unit 

42.700 

Shelters (6) 

226,920 

Subtotal 

$772,260 

Vehicles 

13,786 

Administrative and Personnel Equipment 

3,743 


Personnel 


Total Estimated Fly-Away Cost 


120,338 

$910,127 













APPENDIX B 


Production Costs of Field Bakery Systems 

A summary of the costs of the several systems is shown in Table B—1. These estimates 
are based on our best judgement and costs incurred in contracts for ABS components already 
procured. It is certain that the M-1945 Bakery Plant could not be procured today without 
some redesign effort and some change in certain components, nor would it be desirable to 
reproduce it exactly as it is. The values shown also include an inflation factor. 

Production costs based on amortization of the plant over 20 years and vehicles over five 
years, fuel costs, and personnel costs are strongly in favor of the ABS system. Even on a 
worst case basis for the ABS (22 men, 14,400 pounds bread production) the cost per pound 
of bread is over four cents less than under the other two systems. 

On the basis of a production level of 18,000 pounds per 20 hour day — which is a distinct 
possibility with the ABS — the cost per pound of bread produced is only $0,049. When 
considered on the basis of supplying a 100,000 man force with 0.5 pounds of bread/man/day, 
there is a need for five M—1945's (4.45), four M—1945l's (3.44) and three ABS (2.77), the 
latter based on a production level of 18,000 pounds/day. 

It is clear that personnel costs will always be significantly less for an automated system 
than a manual system. We did not cost out a comparable German system at this time, but 
from the limited information available, it appears as labor intensive as the M—1945 and its 
price was about $500,000 in 1978. 

The fuel usage is shown only for the diesel generator required. An M-1945 using a 
VCM will require a 60 kW generator, which uses twice as much fuel as the 30 kW generator. 
The fuel required per hour for the ABS which uses three burners will be about the same 
as that used by the three ovens of the M-1945's. In any case, the cost of fuel per pound 
of bread baked is minor in comparison to personnel costs. 






Table B-1 


A Comparison of Production Costs for Several Field Bread Baking Systems 
(Calculations are besed on indicated line numbers) 



M-1945 

M-1945 1 

ABS 

1 Vehicles (5 years) 

$ 49,266.00 

$ 49,266.00 

$ 13,786.00 

2 Cost/year (1H5 

9,853.20 

9,853.20 

2,757.20 

3 Equipment (20 years) 

249,667.00 

301,016.00 

776,003.00 

4 Cost/year (3)-20 

12,470.05 

15,050.80 

38,800.15 

5 Equip. & Vehicles (cost/yr) (1)+(3) 

22,323.25 

24,904.00 

41,557.35 

6 Equip. & Vehicles (cost/yr) (1)+{2) 

61.16 

68.23 

113.67 

365 




7 Production/day (pounds) 

11,232.00 

14,512.00 

14,400.00 

8 Cost/pound of bread (6)-(7) 

$0.00544 

$0.00470 

$0.00789 

9 Fuel cost/day* 

72.00 

144.00 

144.00 

10 Cost/pound of bread (9)-(7) 

$0.00641 

$0.01282 

$0.01282 

11 Personnel costs 

393,066.00 

464,068.00 

228.281.02 

12 Number of personnel 

38 

46 

22 

13 Cost/day** (11K365 

1,076.89 

1,271.39 

625.42 

14 Cost/pound of bread (13)-(7) 

$0.09587 

$0.08760 

$0.04343 

15 Cost summary/pound of bread 




Summary of Costs 




Equipment & Vehicles (8) 

$0.00544 

$0.00470 

$0.00789 

Fuel (10) 

0.00641 

0.01282 

0.01282 

Personnel (14) 

0.09587 

0.08760 

0.04343 


$0.10772 

$0.10512 

$0.06414 


'Based on fuel consumer per day by 30 kW Diesel generator for the M-1945 and 60 kW 
Diesel generator for the other two. 

"Cost/day based on 365 days. 


35 









Table B-2 


A Comparison of Personnel Costs for Several Field Bakery Systems 


Personnel costs 





Platoon, LT 

$13,780.80 




Platoon, SGT, E—6 

$14,553.36 




E—5 

$12,277.44 




E—4 

$10,440.00 




E—3 

$9,312.48 




E—2 

$9,312.48 





M 

-1946 

M—1945 1 

ABS 

Platoon Ldr. Lt 


1 

1 

1 

Platoon SGT, E—6 


1 

1 

1 

Shift Ldr, E-5 


2 

2 

2 

Bakers, E—4 


18 

18 

8 

Mechanic, E—4 


1 

1 

1 

Hv Truck Driver, E—4 


1 

1 

1 

Mixer Operators, E—4 


2 

2 


Oven Operators, E—4 


2 

2 


Baker's Helpers, E-3 


4 

4 

4 

Baker's Helpers, E—2 


4 

4 

4 

Lt Truck Driver, E—3 


2 

2 


Slicing, E—3 



2 


Bagging 



2 


Add'nl for VCM, E-2 



2 


Add'nl for Pan Handling, 

E-2 


2 




38" 

46 

22 


36 






























Table B-3 


Estimated Cost of Equipment Required by Field Bakery Systems 



M—1946 

M—1945 1 

ABS 

Mixing and Makeup Trailer 

$83,407 

$83,407 


Ovens(3) 

60,932 

60,932 


Proof Cabinets (3) 

11,276 

11,276 


Sifting Machine 

5,725 



Shelters (6) 

6,622 

6,622 

$226,920 

Ancillary Equipment 

75,511 

75,511 


Vehicles 

49,266 

49,266 

13,786 

Adm. and Personnel Equipment 

5,928 

5,928 

3,743 

Dough Developer 



91,500 

Proofer 



91,500 

Conveyor Oven 



274,500 

Depanning-Cooling 



30,500 

Slicing-Bagging 


14,640 

14,640 

Power and Service Unit 


42,700 

42,700 


$298,667 

$350,282 

$789,789 


37 






APPENDIX C 


Instruction Manual-Operation of Continuous Dough Making 
and Dough Depositing Machine with Pan Indexing 

Sample Calculations For Ingredient Feed Rates 

The continuous mix process requires that a steady stream of dough be supplied from 
the premixer to the developer. In order to keep the premixer filled to the proper level with 
dough, it is necessary to supply it with ingredients in the proper proportions and at the proper 
delivery rates. Therefore, prior to the start-up of the continuous mix operation, it is necessary 
to establish the dry mix and yeast brew formulas and to calculate the feed rates for the dry 
mix, yeast brew and shortening. Since all of these calculations depend upon conditions existing 
in the field, the conditions specitied in the contract have been chosen for the following 
illustration: 

Conditions: 

1. Scaling weight: 18 ounces = 1.125 pounds 

2. Rate of production = 12 loaves per minute, or 
810 pounds per hour 

3. Broth size: 30 minute bath 


Dough formula: 

Percent 


Flour 100.00 

Water 64.00 

Yeast 2.50 

Sugar 5.00 

Salt 2.00 

Dried skim milk solid 3.00 

Yeast Food 0.50 

Mycoban .25 

Shortening 4.00 

Bromate Tablet (1) 

Enrichment: 

Formula Weight 181.25 

Less Fermentation Loss .75 


Total Dough for Scaling 


180.50 











It should be noted that the fermentation loss occurs in the brew due to loss of weight 
by fermentation and by evaporation. The value shown above represents about 1% of the initial 
weight of the brew. 

Fermentation loss will vary with conditions; the more vigorous the fermentation action, 
the dryer the atmospheric conditions and the longer the fermentation time the greater the 
fermentation loss will be. A fermentation time of two to two and one half hours will result 
in a loss of about 2%. Shorter fermentation periods will result in proportionately smaller 
losses. 

Dough Feed Rate 

As previously mentioned, the dough must flow to the developer at a steady rate. In 
establishing this rate, the capacity of all bakery equipment must be considered. A small safety 
factor should be included to allow for the normal fluctuation in bakery conditions so that 
they will not cause unnecessary breaks in the continuous process. In this example, the dough 
feed rate will be 12 x 1.125 = 13.5 Ib/minute; 60 x 13.5 lbs per minute = 810 Ibs/hour. 

A study of the representative formula reveals that 100 lbs of flour will produce 180.5 
lbs of dough. Since only 13.5 lbs of dough are required per minute, then the flour needed 
is 100 x 13.5/180.5 = 7.48 lbs per minute. This will amount to 60 x 7.48 = 449 lbs of 
flour for each hour or 30 x 7.48 = 224.5 lbs of flour for each half hour or each brew batch. 

For convenience in handling, etc., the dough formula is broken down into three ingredient 
blends. 

1. Dry Mix (Pre-blended and packaged) 

2. Yeast Brew (Prepared during operation) 

3. Shortening Blend (Pre-blended and packaged) 

These three ingredient blends contain all of the ingredients required in the dough. Each 
is introduced continuously by an ingredient feeder. 






























Dry Mix Formula 


Flour 

Sugar 

Salt 

Nonfat Dry Milk 
Mycoban 

Mineral Yeast Food 
Total 

10% Used in brew 
Fed as dry mix 


Water 

Yeast, Actively 
Bromate Tablet 
Enrichment Tablet 
10% dry mix 


Shortening 

Total Percent 

Yeast Brew 


Bakers Percent 

100 

5 

2 

3 

0.25 

0.50 


110.75 

11.075 

99.675 


Brew Formula 


64 

2.50 

(D 

( 1 ) 

11.075 

77.575 

4 


99.675 


77.575 

4 

181.25 


The yeast brew includes all ingredients that contribute to fermentation. Each brew must 
be large enough to sustain production for a definite period (in this case 30 minutes). Each 
brew is set at about 85°F and after fermentation of 30 to 60 minutes should be at a temperature 
of 88 to 89°F. The yeast brew feed rate will be the final weight of the brew batch divided 
by the production period covered (in this case 30 minutes). The amount of each ingredient 
used in the brew will be the formula weight of the ingredient multiplied by the weight of 
the flour per brew and divided by 100. In the example, the weight of the flour used per 
brew is 225 lbs and, therefore, the amount of each ingredient used in the broth will be the 
formula weight multipled by 2.25. 


Brew Formula Calculations: 


Water (64 x 2.25) - 144 
Yeast (2.5 x 2.25) - 5.625 

Bromate Tablet (1 x 2.25) * 2.25 
Dry Mix (11.075 x 2.25) - 24.91875 



















The dry mix includes all of the ingredients not inquired for the fermentation that lend 
themselves to preblending and good stability in handling. The amount of each ingredient used 
in the dry mix will be the formula weight of the ingredient multiplied by the weight of the 
flour per half hour and divided by 100. In the example, the weight of the flour used per 
half hour is 225 lbs. Therefore, the amount of each dry mix ingredient required will be the 
formula weight multiplied by 2.25. 

Dry Mix Formula Calculations: 

Pounds For 
30 Minutes 


Flour (100 x 2.25) 225.00 

Sugar (5 x 2.25) 11.25 

Salt (2 x 2.25) 4.50 

Nonfat Dry Milk (3 x 2.25) 6.75 

Mineral Yeast Food (0.5 x 2.25) 1.12 

Mold Inhibitor (Mycoban) (0.25 x 2.25) 0.56 

Setting Feeder Rates 


The ingredient feed rates are adjusted by changing the speed of the feeders. The speed 
of the Brew and Shortening Feeders and the Dough Pump are adjusted by moving the motor 
base to adjust the drive pulley ratio. Before starting to operate the unit the feeders should 
all be pre-set at the desired feed rate. 

The accompanying curves were prepared as a guide in achieving the desired setting. It 
should be remembered that these curves were prepared using available materials under conditions 
that existed at the time. The feed rate will vary with the density of the materials and the 
density will be affected by temperature, moisture, formulation, age of fermentation, etc. 

From the curves select the speed that should produce the desired feed rate. Set the 
feeder at that rate and when the feeder has run long enough to insure that the rate has stabilized 
collect three (3) successive timed samples of one minute duration. Weigh the samples and 
deduct the tare weight to determine the net feed rate per minute. If the three (3) samples 
are similar their average is a pretty accurate determination of the feed rate at that setting. 

If the feed rate is not close enough to the desired rate, make a proportional adjustment 
of the speed and repeat the check. 

If the timed samples are not similar repeat the process until reliable series has been run. 
Make sure to use a technique that results in accurate timing. 































































20 30 50 50 60 70 50 

revolutions per minute tachometer 

Rgure C-3. Yeast brew feeder rate 


44 


















Preparation of Brew: Step Procedure 


The fermentation period is the time that elapses between the setting of the broth and 
the entry of broth into the premixer. Therefore, if a one-hour fermentation period is to be 
used, the operator arrives approximately two hours before the mixer is to be started. He 
should check to see that there is an adequate supply of hot water and should then proceed 
to set the first brew. 

1. Accurately scale off all dry ingredients needed for one batch. 

2. Check the tank inlet and outlet valves to be sure they are closed. 

3. Check cleanliness of tanks. 

4. Open water inlet valve of tank to be filled. While water is running into the tank, the 
water temperature should be adjusted if necessary. Water temperature requirements vary 
with condition including ambient and ingredient storage temperature. Select the water 
temperature that will produce a final temperature of approximately 89° to 91° at the 
end of the fermentation period. Using sucrose, the water temperature should be 
approximately 86°F. 

5. When the water level covers the agitator blade, turn on the agitator and introduce all 
dry ingredients except the yeast. 

6. At the proper time, add the yeast. The fermentation period starts when the yeast is 
added and is generally about one hour. 

7. The brew should be checked periodically for foaming, which can be reduced by adding 
a small amount of shortening. 

8. During fermentation the brew should be checked periodically for a normal temperature 
rise. 

9. Repeat above procedure in setting subsequent batches. 

One of the two tanks supplied is required every 30 minutes or so depending on the size 
of the batch. Therefore, if it takes 10 minutes to prepare a brew it will be only 20 minutes 
old when ready for use and 50 minutes old at the end of use (average age 35 minutes). Larger 
tanks and more tanks are recommended for longer fermentation time and longer production 
periods. 

Pre-Start-Up Check List 

Approximately 15 minutes before starting up the unit, checks should be made to ensure 

that: 


45 








1. Shortening holding tank outlet, supply is available and heater is turned on, if required, 
and set at the desired temperature. 

2. Handles of the three-way brew valves are properly positioned. 

3. Dry mix supply bin is full. 

4. Developer by-pass valve is open, and bowl cover is secure. 

5. Divider shaping block and cover are in place and secure. 

6. Divider blades are opened approximately 1/8 of an inch. 

7. Dough pot is under divider, and bucket is under by-pass pipe. 

8. Panner belts and indexing fingers move freely. 

9. Dough scale is set for 18 ounces. 

10. All equipment operates and panel meters are at correct settings. 

11. All fittings are secure. 

12. Divider oil, dusting flour, thermometer, and scraper are available. 

13. All equipment meets standards for denliness. 

Start-Up: Step Procedure 

1. Open valve from the No. 1 fermentation tank to the brew feeder pump. 

2. Turn control panel main switch on "ON" position. 

3. Turn brew selector switch to "ON" position. 

4. Turn shortening selector switch to "ON" position. 

5. After shortening blend and brew are flowing uniformly from the nozzles, turn feeder 
selector switches to "OFF" position. 

6. Turn on premixer and check visually for operation. 

7. Turn on developer motor. Turn on developer clutch. 

8. Set developer speed control dial to run developer impellers at approximately 20 rpm. 















9. Turn on shortening and brew feeders. With brew now entering the premixer, turn 
on the dry mix feeder. 

10. Visually check consistency of dough in premixer. 

Visually check the feeder tachometer meters. 

11. When the dough in the premixer reaches its proper level, turn on the dough pump. 

12. When dough begins to flow out of the developer by-pass valve, turn the valve for flow 
to the developer. 

13. Turn up developer speed to maximum. 

14. Start divider when dough extrudes in a steady stream and is showing signs of some 
development. 

15. Check dough for development. When signs of optimum development are observed, 
reduce developer impeller speed to correct rpm. 

16. Take a doughpiece sample and check it for correct scaling weight. 

17. When dough development and scaling weight are satisfactory, turn on divider panner 
control and guide the first strap of pans to the depositing point. 

18. Check dough weights until conditions have stabilized and thereafter as required. 

19. Check all ingredient streams periodically for flow and temperature. 

20. Record operating conditions accurately on daily record sheet at regular intervals. 

Start-Up Procedure 

In time the operator of this system will develop his or her own techniques. The following 
is offered as a guide to help in the initial production efforts. 

When starting up the unit, allow some of the liquid ingredients to run in to the premixer 
for a few seconds before starting the dry mix feeder. When it is sure that the liquid ingredients 
are flowing, start the dry mix feeder. This will help prevent raw dry mix from entering the 
dough pump. The dough pump cannot pump dry mix and could be damaged. Allow the 
premixer to fill, then start the dough pump. 

Allow some of the dough to bypass the developer, to purge that initial portion of premixed 
dough which may not be properly mixed or blended. As soon as the dough becomes uniform, 
close the bypass valve and fill the developer. Running the developer at low speed during 
filling helps prevent short circuiting to the developer outlet. 









It takes about 2 minutes to fill the premixer and about 30 to 40 seconds to fill the 
developer. During the preliminary trials, the timing of the starting sequence was found to 


be as follows: 

Time 


Min:Sec 

Function 

0:00 

Start Yeast Brew and Shortening Feeders 

0.10 

Start Dry Mix Feeder and Allow Premixer to fill to 
operating level 

2:00 

Start the Dough Pump with Bypass Valve open 

2:30 

Close the Bypass Valve and Fill the Developer 

3:20 

Turn the Developer to full speed 

4:00 

Start the Divider 

Reduce the Developer speed to normal 


4:15 


Start to Pan dough