FIELD OF THE INVENTION
The present invention relates to an improved oven/system for bakery product and baking
process involving the same. More particularly, the invention relates to improved system and
process with infra red rays adapted for pre-baking bakery products.
BACKGROUND AND PRIOR ART
Conventionally different bakery product baking industry uses the following types of ovens:
Indirect fired oven, Direct fired oven, Hybrid ovens and Electric ovens. In indirect fired ovens,
the heat source is independent of the baking chamber atmosphere and heat transfer takes
place through heat exchanger. In direct fired ovens, heat transfer takes place directly
through flames to the baking chamber. The hybrid ovens are the combination of both direct
and indirect fired ovens and the electric coil heaters are used inside the baking chamber as
a heat source.
Bakery products comprises the vast range of products manufactured in the bakery industry
such as biscuits, breads, baguettes , bread sticks, cookies and like.
The major drawback of the prior art technology is that the heat transfer takes place from air
to air for which the thermal conductivity is quite low and hence the net heat utilized by the
system is less. In due course of time the efficiency of the oven drastically reduces because
of the radiator tubes getting coated/choked with carbon particles especially during burning of
unclean fuel. Apart from these factors, the response time of the oven is also quite high. And
hence reasons were explored for how to enhance the productivity of the oven output by
reducing the baking time. In all the above mentioned types of ovens the effect of heating is
more on the surface than the core of the biscuit. The substantial difference is maintained
throughout the baking profile and the core temperature gradually increases to the desired
level in a longer duration resulting in longer baking time.
The reduction in baking time is possible only by increase in core temperature at a faster rate.
Infra red heaters are identified for the same purpose explained earlier.
US 5,378,872 discloses an apparatus employing directed infrared radiation emitted by two
spaced sources delimiting a baking space for a plate receiving food to be baked. The two
sources are separated by a space of 5 to 10 centimeters. The lower source is preferably
located less than one millimeter from the bottom of the support, which is constituted by a

circular removable plate. The plate is supported and guided rotationally with respect to the
floor of the apparatus and is made of an infrared-permeable material and cooperates by its
periphery with a constant-speed positive rotational drive arrangement. The drive confers a
sequential character on the strong radiation energy of the infrared sources.
Effect of Near-infrared Radiation and Jet Impingement Heat Transfer on Crust Formation of
Bread by E.E.M. OLSSON, A.C. TRAGARDH, AND L.M. AHRNE , Vol. 70, Nr. 8, 2005
discloses rapid heat transfer methods can be used to speed up the baking process and
create new product properties. The study investigates the effect of air jet impingement and
infrared radiation (alone or in combination) on crust formation of par-baked baguettes during
post-baking. The parameters investigated are crust color, crust thickness, total water loss,
and heating time. The results show that infrared radiation and jet impingement, as compared
with heating in a conventional household oven, increased the rate of color development of
the crust and shortened the heating time. The fastest color development was obtained by
combining infrared and impingement heating. The water loss rate was increased due to the
high heat transfer rate, but the total water loss was reduced because of the shorter heating
time. Crust thickness was most dependent on heating time and crust temperature. In
general, the crust was thinner for infrared-heated baguettes. A standard recipe for white
bread was used: 62% wheat flour, 34% water, 3% yeast, 0.6% salt, and 0.6% improver
(Lecimax 2000, Nordfalksbakels, Sweden). The bread was formed as a small baguette and
prebaked in a rack oven at 155 °C for 12 min. Prebaking created a baguette with a ready-
baked crumb and a thin, colorless crust. The length of the baguette was about 12 cm and
the diameter was 40 to 50 mm after baking. The baguettes were immediately frozen and
stored in a -40 °C freezer. Before post-baking, the baguettes were thawed in +30 °C and
80% relative humidity for 1 to 2 hour.
Effect of Infrared Baking on Wheat Flour Tortilla Characteristics by F. Martinez-Bustos, S. E.
Morales, Y. K. Chang, A. Herrera-G6mez,M. J. L. Martinez.L. Banos, M. E. Rodriguez, and
M. H. E Flores, Vol. 76, No. 4,1999 discloses a new and improved method for baking wheat
flour tortillas was evaluated. The method was faster and reduced tortilla dehydration. The
aim of the study was to evaluate the efficiency of the infrared baking method on rollability,
puffing, layering, color (lightness), and texture (cutting force and tensile strength)
characteristics of wheat tortillas formulated and formed by the traditional (hand-rolled) and
commercial (hot-press) methods. These tortillas were also compared with traditional tortillas
cooked on a hot griddle and commercial tortillas cooked in a three-tier, gas-fired oven. In the
infrared radiation (IR) method, tortillas were baked for 17 or 19 sec by IR using black-body
radiation at a selected wavelength band and emission temperatures of 549 or 584°C. IR-

baked tortillas showed good characteristics of reliability, puffing, layering, color, and texture.
The loss of moisture during baking of the tortillas formed by hot-pressing and baked by IR
was significantly lower than that of tortillas baked by traditional and commercial methods. X-
ray diffraction of tortillas prepared by the traditional process and baked by the IR method
showed a pattern similar to that of homemade tortillas baked on a hot griddle. The average
energy used by the IR oven was less than that used in the commercial method which, in
turn, is more efficient than the traditional hot griddle method.
The drawbacks of the above mentioned prior art is that the system applies IR in post-baking
stage and uses combination of IR and jet impingement which makes the baking method
complex and time consuming The incorporation of IR source on top and bottom of bakery
product has been disclosed in the prior art which is a complex process and expensive.
The prior art emphasize on the increase the rate of colour development of crust and
shorten the heating time, but not to uniformly heat the core and surface of the products in
pre-baking zone and which shorten the baking time. The prior art generally uses an MW IR
Heater (i.e. Medium Wave) while the present invention has used a SW IR Heater (Short
Wave).
The present inventors have found that if there can be a heating system at the pre-baking
stage it will be a big advantage which will definitely improve the overall efficiency of bakery
product baking process. Hence Infra red heating system has been implemented for heating
bakery products at the pre-baking stage itself.
OBJECTS OF THE INVENTION
It is an object of the present invention to overcome the drawbacks of the prior art.
It is another object of the present invention to provide an improved system for bakery
products baking oven.
It is yet another object of the present invention to provide an improved system and process
adapted for bakery products baking oven with heating at the pre-baking stage which works
on the principle of heat transfer through infra red rays.
It is yet another object of the present invention to provide the bakery products at an equal
distributed moisture level across the biscuit in turn helps improving the quality.

SUMMARY OF THE INVENTION
According to one of the aspect of the present invention there is provided an improved
baking system for baking of bakery products, said system comprising
an oven means;
plurality of heater means;
a band means connected/associated with said heater means and oven means adapted to
carry the wet dough to the heater means and to the oven means;
wherein said heater means is positioned ahead of said oven means adapted for pre-baking
bakery products.
According to another aspect of the present invention there is provided sn improved baking
process for baking of bakery products in an improved baking system for baking of bakery
products, said process comprising steps of
(i) Carrying/conveying the wet dough bakery products from the conveyor means
to the heater means adapted for pre-baking of the wet dough bakery
products;
(ii) pre-baking of said wet dough bakery products by said heater means;
(iii) final baking of said pre- baked bakery product in the oven means adapted to
obtain the final baked bakery products ;
(iv) cooling and packing of said final baked bakery products;
wherein said pre-baking of said wet dough bakery products is functioned/operated
ahead of said final baking.
DESCRIPTION OF THE INVENTION
The present invention relates to an improved system and process which is with the principle
of heat transfer at the pre-baking stage through a different media i.e. infra red rays. The infra
red heaters are fitted in appropriate place at the entry point of bakery products in the oven

chamber for heating the product. Heat transfer rate of infra red rays is higher and thereby
enabling the efficient heat transfer.
It has been found that with the given chemical characteristics of bakery products dough,
radiations of particular wavelengths are effective to raise the core temperature to the desired
level in a short span of time. These wavelengths fall in the spectrum of Infra red waves and
hence infra red heaters are used.
According to one of the embodiment of the present invention there is provided an improved
biscuit baking oven/system for improved heat transfer rate comprising infra red heaters kept
close to the product surface and where the distance between the heat emitting surface and
heat absorbing surface is reduced.
The improved baking system with the improved heat transfer comprises of Infra red heating
module/unit in the pre-baking area and an Indirect fired oven with plurality of baking
chambers and flue gas circulating system comprising arrangement of conduits for conveying
the flue gases and a fan for ensuring the circulation of the same.
A baking system with improved heat transfer comprising of Infra red heating module in the
pre-baking area and a Direct fired oven with a plurality of baking chambers and comprising
of multiple ribbon burners for combustion and transferring of heat to the product.
A baking system with improved heat transfer comprising of Infra red heating module in the
pre-baking area and a Hybrid oven with indirect fired system with baking chambers and flue
gas circulating system comprising arrangement of conduits for conveying the flue gases and
a fan for ensuring the circulation of the same and direct fired system comprising of baking
chambers with multiple ribbon burners for combustion and transferring of heat to the product.
The improved baking system for baking of bakery products comprising an oven means;
plurality of heater means; a band means connected/associated with the heater means and
oven means for movement of bakery product from oven means to heater means where the
heater means is positioned ahead of said oven means adapted for pre-baking bakery
products.
The heater means is substantially placed in 1 Inch to 8 Inches with the surface of the band
means to reduce the distance between the heat emitting surface and heat absorbing
surface.

The heater means comprises infra red heaters. The oven means is selected from direct fired
modules, indirect fired modules and hybrid fired modules and like.
The system further comprising a conveyor means operatively connected with said band
means.
The conveyor means comprising first conveyor means adapted to carry the wet dough to
said band means and second conveyor means adapted to carry the final bakery product
from the band means for cooling and packaging where the first conveyor means is ahead of
second conveyor means. The band means comprises steel wire.
According to another embodiment of the present invention there is provided an improved
heat transfer/baking process for the baking system where in the heating means comprises of
Infra red heating in pre-baking area with direct fired modules or indirect fired modules or
hybrid of direct and indirect fired modules in combination.
The improved baking process for baking of bakery products in the improved baking system
having steps of carrying/conveying the wet dough bakery products from the conveyor means
to the heater means for pre-baking of the wet dough bakery products; pre-baking of the wet
dough bakery products by the heater means; final baking of the pre- baked bakery product
from the heater means to the oven means to obtain the final baked bakery products and
cooling and packing of said final baked bakery products;
The pre-baking of said wet dough bakery products is carried out prior to the final baking. The
wet dough is substantially placed in 1 Inch to 8 Inches with said heater means adapted to
reduce the distance between the heat emitting surface and heat absorbing surface
The duration of pre-baking of said wet dough bakery products in said heater means is 2
Second to 12 Second.
The duration of final baking of said pre- baked bakery product is 3.5 Minutes to 6.5 Minutes.

Further the temperature of the pre-baking stage and final baking stage are 40 °C to 100 °C
and 120° C to 310 ° C respectively. Process as claimed in claim 7, wherein the temperature
of the pre-baking stage is 40 o to 100 °C.
It is possible by way of the above disclosed process of pre heating to provide correct and
equally spread out moisture in the bakery products.
Advantageously, the process enables a simple and effective manner of pre heat the dough
piece.
Advantageously, the above process according to the invention of pre heating the dough is
carried out efficiently by way of a selective combination of heating system to produce the
biscuit in bakery industry.
The present invention provides selective system with interactive constructional features
adapted to facilitate the above pre heating of wet dough piece, which is difficult to spread the
heat equally at the surface and core.
The present invention, the said oven/system has the following advantages:
• Better and quick heat transfer at the pre-baking stage through infra red rays
• Better and faster heat transfer to the core which helps in enhancing the reaction
speed
• Better and uniform heat transfer which keeps the moisture level uniform through out
the product.
• Better temperature profile control and consistent performance as the response time
of the oven is less.
• Achieving reduction in baking time of the product and thereby enhanced productivity.
• Achieving reduction in fuel and power consumption since the efficiency is high as
compared to conventional oven.
• Delivering trouble free sustained operation is possible.
• Helping in offsetting the impact of fuel cost increase on the business because fuel
consumption will be less.
• Helping in reducing the adverse effect on environment as GHG emissions will be
less.
Accordingly, the present invention provides an improved design for baking oven with infra
red heating at the pre-baking process and enhanced efficiency as compared with the

existing designs. The efficiency of the oven design of the present invention is much higher
when compared to existing oven alone.
The reduction in energy consumption per Ton of production is of the order of 30 Units/Ton.
( ie. a 15-17% reduction in energy consumption.) . Particularly the reduction in energy
consumption is also remarkably improved as it is found that the reduction in energy
consumption per kg of production is of the order of 10% approximately.
BREIF DESCRIPTION OF THE ACCOMPANING DRAWAINGS
Figure 1 illustrates the elevation view of the present system.
DETAILED DESCRIPTION OF THE ACCOMPANING DRWAINGS
The nature of the invention, its objects and advantages are discussed in further details in
relation to non-limiting exemplary illustration of the process/system as per the following
accompanying figure (Figure 1).
Although the invention has been described with reference to specific embodiment as in
figure 1, this description is not meant to be construed in the limiting sense. Various
modifications of the described embodiment, as well as alternate embodiment of the
inventions will become apparent to persons skilled in the baking art upon reference to the
description of the invention or by following routine experimentation. It is therefore
contemplated that such modification can be made without departing from the spirit or scope
of the present invention as defined
Figure 1 shows the elevation view of an embodiment of the present invention fitted on top of
the Steel Wire Band 140 which carries the biscuit/bakery product wet dough 120 in to the
oven 130 for baking the dough 120 to convert in to Biscuits bakery product 150. The wet
dough 120 being formed in to particular shape and size being transferred by panner web
conveyor 110 to steel band 140 and passes under the IR heater set up 100 for uniform pre
heating of the dough 120 from the ambient temperature. The Infra Red heaters heats not
only the surface but also increases the core temperature equally to surface at a faster rate
than the convention way of heating the dough which helps in reducing the backing time
drastically which in turn increases the productivity also. The pre heated dough piece 120A
enters in to the conventional for further process of baking and comes out as baked biscuit /
cookie 150 and transferred to cooling conveyor 170 for cooling and further packing process.

Examples:
Table 1 provides a comparative study data demonstrating the reduction in baking time and
cost of manufacturing using IR at pre-baking stage.

It is found that the savings in energy cost/kg is 0.28.
Savings:- Rs. 0.50/kg
It is concluded that pre-baking the baking oven reduces the baking time, energy
consumption and cost /kg of the baked products.

WE CLAIM
1. An improved baking system for baking of bakery products, said system comprising
an oven means;
plurality of heater means;
a band means connected/associated with said heater means and oven means
adapted to carry the wet dough to the heater means and to oven means;
wherein said heater means is positioned ahead of said oven means adapted for pre-baking
bakery products.
2. The improved baking system as claimed in claim 1 wherein said heater means is
substantially placed in 1 Inch to 8 Inches with said surface of said band means
adapted to reduce the distance between the heat emitting surface and heat
absorbing surface.
3. The improved baking system as claimed in claim 1 wherein said heater means
comprises infra-red heaters.
4. The improved baking system as claimed in claim 1 wherein said oven means is
selected from direct fired modules, indirect fired modules and hybrid fired modules
and like.
5. The improved baking system as claimed in claim 1 further comprising a conveyor
means operatively connected with said band means.
6. System as claimed in claim 5 wherein said conveyor means comprising
first conveyor means adapted to carry the wet dough to said band means; and
second conveyor means adapted to carry the final bakery product from the band
means for cooling and packaging;
said first conveyor means is ahead of second conveyor means .
7. The improved baking system as claimed in claim 1 wherein said band means
comprises steel wire.
8. An improved baking process for baking of bakery products in a system as claimed in
claim 1, said process comprising steps of

(i) Carrying/conveying the wet dough bakery products from the conveyor means
to the heater means adapted for pre-baking of the wet dough bakery
products;
(ii) pre-baking of said wet dough bakery products by said heater means;
(iii) final baking of said pre- baked bakery product in the oven means adapted to
obtain the final baked bakery products ;
(iv) cooling and packing of said final baked bakery products;
wherein said pre-baking of said wet dough bakery products is functioned/operated
ahead of said final baking.
9. Process as claimed in claim7 wherein said wet dough is substantially placed in 1 Inch
to 8 Inches with said heater means adapted to reduce the distance between the heat
emitting surface and heat absorbing surface.
10. Process as claimed in claim 7 wherein the duration of pre-baking of said wet dough
bakery products in said heater means is 2 Second to 12 Second.
11. Process as claimed in claim 7 wherein the duration of final baking of said pre- baked
bakery product is 3.5 Minutes to 6.5 Minutes.
12. Process as claimed in claim 7, wherein the temperature of the pre-baking stage is
40oC to 100oC.
13. Process as claimed in claim 7, wherein the temperature of the final baking stage is
120OC to 310°C.
14. Process as claimed in claim 7 wherein the reduction in energy consumption per Ton
of production is of the order of 30 Units/Ton.

The present invention relates to an improved baking system and process for baking of
bakery products. The system comprising an oven means (130), plurality of heater means
(100), a band means (140) connected/associated with the heater means (100) and oven
means (130) to carry the wet dough (120) to the heater means (100) and to the oven means
(130).The heater means (100) is positioned ahead of the oven means (130) adapted for pre-baking
bakery products. The system further comprises a conveyor means. The conveyor
means comprises a first conveyor means (110) and second conveyor means (170).