PT104097B - PROCESS FOR THE INDUSTRIAL MANUFACTURE OF BREAD SHAPE WITH A CELL OF COLOR INTENSITY NOT SUPERIOR TO THE MIOLO, AND CORRESPONDING DEVICE - Google Patents

Abstract

The invention relates to a process for the industrial manufacture of bread in a form with a color density not exceeding that of the bolus and corresponding apparatus. It comprises a step of preparing bread (1) prepared for cooking; A COOKING STAGE IN AN OVEN (4) AND A STAGE OF DEVELOPMENT. THE COOKING HAS PLACE IN A VAPOR ATMOSPHERE THAT PRESENTS A MOLAR FRACTION OF STEAM WATER OF OR MORE THAN 70 PERCENT AND A TEMPERATURE EXCEEDING OR EQUAL TO 80 DEGREES CENTRAL AND INTERIOR OR EQUAL TO 110 DEGREES CENTRAL. BEFORE THE STAGE OF DEVELOPING, ACTIVE DRYING OF A BREAD FACE IS VIEWING THE COOKED BREADFUL (5), AND, DURING THE REFERENCE STEP (C) OF DEVELOPING, MEANS FOR GRILLING ACT ON THE REFERENCE FACE OF THE BREAD ON THE VIEW TO REMOVE BREAD SHAPE.

Description

Field of the invention

The invention is in the field of the industrial bakery, in particular in the field of the industrial manufacture of crust-free bread or a crust that has a crumb-like appearance.

More specifically, the invention relates to a process for the industrial manufacture of loaf bread having a crust of a color intensity not exceeding that of the crumb, comprising at least one step (a) of preparing shaped baking breads consisting of by a dough contained in a form; a step (b) for baking said oven-formed breads, said shaped breads for continuous baking in said oven, circulating within said oven and continuously leaving said oven in the form of baked shaped breads; and a step (c) of unmolding said baked loaves to obtain a loaf.

The invention also relates to a device which, thanks to its particular characteristics according to the invention, is in a position to perform said manufacturing procedure.

State of the art

Known processes for the industrial manufacture of crust-free bread are classically based on obtaining a crust-bread followed by separation of said crust using mechanical means.

Typically, the crust-shaped bread has a parallelepiped shape and the crust is separated by applying a cut on each of the six faces of the bread by means of a blade system. Crust cutting presents important technical problems. In particular, it is difficult to make a clean and adjusted cut that completely eliminates the crust, minimizing waste and without structurally deteriorating the bread. A known solution to facilitate this crust cutting, disclosed in ES 2217991 A1 and ES 2221590 Al as well as US 2004/01 56966 Al, is to cool the bread to a low temperature prior to making such a cut. Although this solution improves the conditions under which it is cut, it implies the use of a sophisticated cutting material and installation.

On the other hand, all known processes based on mechanical separation of the bread crust necessarily entail a high loss of raw material. Typically, this loss is greater than 45 percent of dough.

Another known manufacturing process is to perform bread baking by microwave or radiofrequency, a process whereby a loaf with a thin white crust directly resembling that of the crumb is obtained, making it unnecessary to perform a cut to separate the crust. This known process has several drawbacks. Firstly, the physical mechanism of baking is very different from that produced in a thermal oven: heating takes place directly in the dough and not by heat transmission from the outer surface of the bread to the inner dough. In order to obtain a bread having a crumb with the same organoleptic characteristics and texture as a traditional bread, say a bread baked in a thermal oven, it is necessary to make very precise adjustments to obtain a satisfactory product. In particular, the oven power and cooking time must be adjusted and controlled very precisely. On the other hand, the design of the oven is complicated because a homogeneous distribution of microwave radiation within the microwave has to be achieved to avoid imbalances in the baking state of the bread. All this makes it difficult to apply this process on an industrial scale when it is necessary to produce a large number of breads in series so that they must all have constant characteristics in terms of appearance, consistency and organoleptic properties.

US 2007 11084 A1 (LLAVINA et al) discloses a steaming bread baking process in which the oven temperature is kept low to prevent crust coloring. Said US 2007 11084 A1 describes experimental tests performed on a loaf but does not address the technical problems that must be overcome in order to carry out a similar process on an industrial scale.

Summary of the Invention

The purpose of the invention is to provide a process for the industrial manufacture of bread with a crust having a color intensity not greater than that of the crumb, such that no mechanical separation of the crust is necessary, and overcoming the drawbacks of the condition. mentioned technique.

This purpose is achieved by a process for the industrial manufacture of bread of the type indicated in the principle in which during the baking step (b) an atmosphere of steam is present which has a molar fraction of steam. of water exceeding 70 per cent and a temperature greater than or equal to 80 degrees centigrade and less than or equal to 110 degrees centigrade,

In the sense of the present invention, "steam atmosphere" means an atmosphere with a high water vapor content, in particular with a molar fraction of water vapor greater than or equal to 70 per cent, the remainder being normally air. Preferably, however, said vapor atmosphere is composed entirely of water vapor.

The use of low temperature steam cooking is new in the field of industrial bread making processes using a continuous feed oven. Thanks to the fact that the steam atmosphere in which bread is baked is at a relatively low temperature, below 110 degrees centigrade, chemical reactions known as Maillard reactions which are responsible for the color change of the bread surface are inhibited. . This gives a baked loaf which has a similar appearance and consistency to that of a loaf from which the crust has been mechanically removed. Experimental tests performed by the applicant have shown that by maintaining the steam atmosphere in the furnace under the specified conditions, it is possible to apply the process on an industrial scale and obtain a predictable and uniform result.

The cooking time required, although longer than in a traditional air atmosphere oven, remains at useful values for industrial manufacture, thanks to the fact that water vapor has a much higher thermal conductivity than air, with that the heat transmission coefficient on the bread surface is higher. This partly compensates for decreased heat transmission due to a lower temperature of the atmosphere surrounding the bread.

Preferably, the vapor atmosphere within the oven remains at a pressure greater than or equal to atmospheric pressure. Operating with a furnace overpressure makes it easier to maintain proper steam atmosphere conditions. This is especially true when working with a continuous feed furnace, as air from outside is prevented.

The method according to the invention further comprises a step of wrapping the baked breads baked at the exit of the oven to facilitate their unmolding. This wrapping step consists of prior to the unmolding step (c) actively drying one-sided face of these baked shaped breads, and during said unmolding step (c) pressing means acts on said bake. in view of the previously dried bread to extract a loaf of each of said baked shaped breads. In other words, a face face of the bread is superficially dried so as to be able to apply on that face gripping means which effect the extraction of the bread in relation to the shape. This unmolding process is especially advantageous in the process according to the invention, in which the breads obtained from the oven are difficult to unmold because they have a crust with little mechanical strength. The surface drying of a bread face according to the invention leaves no trace in the final product. In fact, a steamed bread has a higher humidity than a bread baked in a traditional air oven, and as a result of this unmolding, a phenomenon of free water diffusion occurs from inside the bread. to the surface of the dry face, with which the latter soon recovers the lost moisture and ends up looking the same as the other faces of the bread.

Advantageously, said active drying operation is carried out by exposing said face of the bread to a forced hot air stream preferably having a temperature of greater than or equal to 60 degrees centigrade and less than or equal to 80 ° C. degrees centigrade and a relative humidity of 10 per cent. Tests have shown that forced hot air drying allows a sufficiently sufficient surface to be sufficiently quickly applied to a surface.

check that the exterior means of grasping. Also preferred mentioned are optimal for surface surface which is sufficient but which, under the wetness of the conditions obtain a drying in turn, permits further recovery of said surface without leaving traces in the final product.

Preferably, the gripping means acts by applying an aspiration on the face of the pre-dried bread of the baked bread. This grip is suitable for working on a steamed and superficially dried bread: it allows the loaf to be easily extracted without a trace. On the other hand, it enables the bread to be conveyed from the unmolding operation to transport it to the final packaging and packaging stages.

Preferably, conveying means circulate the shaped loaves for baking within the oven following globally vertical circulation paths. This allows a sufficiently large path of the loaves formed within the oven without exaggeratingly increasing the dimensions of said oven. It should be borne in mind that in the process according to the invention the baking time is longer than in a traditional air oven because the baking time of the shaped breads is longer. On the other hand, this solution makes it possible to use a vertically extending furnace, with the inlet and outlet positioned at the low oven level, as the steam losses are much lower than when using a horizontal furnace with a continuous path. straight line.

Advantageously, the baked loaves which are introduced into the oven have a length corresponding to the length of the packaged loaves to be marketed and which are the result of a final step of wrapping and packaging the baked loaves from the oven. Thus, it is not necessary to cut bread. Preferably, the length of the shaped breads for baking is less than or equal to 40 centimeters. The process according to the invention is especially suitable for the use of small shaped baking breads. In fact, unlike conventional air oven baking processes in which it is sought to minimize the outer surface of the shaped breads for baking to minimize shredded crust losses, in the procedure according to the invention it is preferred that the shaped breads for baking bake have the largest outer surface possible to facilitate low-temperature cooking. This circumstance is used to place shaped loaves of bread into the oven that already have the dimensions of the final product to be marketed, thus avoiding having to cut the breads to the length of the breads to be marketed later. On the other hand, when working with small shaped breads, it is easier to use an oven with a vertical circulation of the shaped breads.

Optionally, during the cooking step (b), a forced circulation of the steam atmosphere within the oven is maintained, thereby facilitating the maintenance of homogeneous conditions in the oven.

The invention also comprises an equipment having special characteristics to power and IRF ¹ ^ hllili this process, according to what is described in the following detailed description of embodiments of the invention.

Brief Description of Drawings

Other advantages and features of the invention are appreciated from the following description, in which, without limitation, preferred embodiments of the invention are described with reference to the accompanying drawings. The figures show:

Fig. 1 is a schematic representation of a first embodiment illustrating the entry, transit and egress of breads in the steam atmosphere oven according to the invention;

Fig. 2 is a figure analogous to Fig. 1 illustrating a second embodiment;

Figs. 3a-3h is a schematic representation of the different stages of the baking bread preparation step, in which the breads are shown in front view;

Figs. 4a-4e are a schematic representation of the different steps of the process for unmolding baked breads baked in the oven, in which the breads are shown in front view.

Detailed Description of Embodiments of the Invention

The first embodiment illustrated in Fig. 1 is in an oven 4, in which the loaves 1 shaped for baking enter through an inlet conveyor belt 12 and are placed in wide flat containers 11 which constitute transport means within the oven. oven 4. Said containers 11 form several columns. In each of these columns, the containers 11 move vertically, in alternating directions between two consecutive columns. To facilitate the illustration in Fig. 1, only four of said container columns 11 have been shown schematically. Of course, an oven 4 according to the invention may be provided with a different number of said container columns 11.

Baking buns 1 enter through an oven inlet opening 4 carried by the inlet conveyor belt 12, move vertically in the containers 11 within the oven 4, alternately upwards and downwards in successive container columns 11 and exit through an outlet opening 15 in the form of baked shaped breads 5 carried by an outlet conveyor belt 13.

Inside the oven 4, a vapor atmosphere is maintained which, in the preferred embodiment described herein, is formed entirely of water vapor at a pressure slightly above atmospheric pressure and slightly overheated, but at a temperature below 110 degrees. centigrade. This water vapor atmosphere is maintained in a controlled manner thanks to means (not shown) of controlled injection of a water vapor flow in the oven 4, combined with means (not shown) for measuring the thermodynamic conditions of the steam atmosphere. in said oven 4. Optionally, inside the oven 4 are arranged convectors (not shown) which maintain a forced circulation of the vapor atmosphere inside the oven. The circulation that these convectors create is smooth and is intended to homogenize the conditions of the water vapor atmosphere inside the oven 4.

As can be seen from Fig. 1, the inlet and outlet openings 14 of the oven 4 are placed in the lower portion of said oven, thereby minimizing water vapor losses through said openings and preventing the entry of air from outside.

Under the conditions indicated, the baking time 4 of the loaves 1 formed for baking must be at least 30 minutes. To guarantee a production of 1000 units per hour, the distance traveled by breads 1 inside oven 4 is over 100 meters. The dimensions of oven 4 are approximately as follows: 5 meters high, 2 meters wide and 3 meters deep. As has been said, this oven 4 has the advantage of taking up much less space than a conventional horizontal oven.

In Fig. 2 a second embodiment of the oven 4 is shown schematically, differing from the first in that, as bread conveyor means within the oven, the containers 11 have been replaced by a vertical axis helical strap. As the containers 11 of the former form of former conveyor belt are distributed in several columns alternating an upward circulation with another downward circulation.

In schematic form: the dotted arrows indicate the helical linear path, while the vertical continuous stroke arrows indicate the overall vertical path along the propeller axis. The other features of oven 4 are essentially the same as those of the first embodiment described above.

In Figs. 3a-3h, the successive phases of the preparation stage of loaves formed breads are represented schematically.

It is understood that this step is not essentially that of what is applicable in the known procedures of the step state is shown and described below for a better understanding of the overall procedure considered. A dispenser 16 containing a kneaded dough (Fig.3a) provides a regular amount of dough 2 (Fig.3b) that corresponds to a loaf of bread. This mass 2 rests (Fig.3c) and then undergoes an operation to obtain a flat laminar mass (Fig.3d) which then coils over itself (Fig.3e). Next, put the rolled dough 2 (Fig.3f) into a form 3 and let the dough ferment until it reaches the desired height (Fig.3g), and finally form 3 with a lid 18. (Fig.3h) resulting in the baking bread 1 which will be introduced into the oven 4 for baking as explained above with reference to Figs. 2 and 2.

Form 3 has dimensions corresponding to those of the final shaped bread to be marketed.

Figs. 4a-4e schematically depict the different steps of the process of unmolding the baked shaped breads 5 leaving the oven 4.

Baked shaped loaves 5 (Fig. 4a) exit from oven 4 via outlet conveyor belt 13 (Fig. 1 or 2) and an electromagnetic clamping device (not shown) removes lid 18 of form 3 (Fig. 4b). ) leaving a face 7 of mass 2 in view. Thereafter, drying active means 9 (Fig. 4c) launches on said face 7 in view of mass 2 a forced hot air stream 17 at a temperature greater than or equal to 60 ° C. degrees centigrade and less than or equal to 80 degrees centigrade and with a relative humidity of 10 percent or less. Next, the bread is unmolded (Fig. 4d) using gripping means 8 which are applied on the face 7 of the previously dried sight bread and removed to achieve the extraction of the bread 8 in a manner. These gripping means 8 consist of vacuum suction cups which are applied against the face 7 of the exposed bread. Finally, this unformed loaf 6 is classically subjected to a final wrapping step (not shown) comprising cooling and a package to obtain the final product, i.e. a packaged loaf having a dimensions corresponding to those of shape 3.

Claims (7)

Process for the industrial manufacture of bread with a crust of a color intensity not exceeding that of the crumb, comprising at least one step (a) for the preparation of baking breads (1) consisting of a dough (2) of bread contained in a form (3); a step (b) of baking said shaped breads (1) in an oven (4), said shaped breads (1) entering for continuous baking in said oven (4), circulating within said oven (4) and continuously leaving said oven (4) in the form of baked shaped breads (5); and a step (c) of unmolding said baked loaves (5) into a loaf of bread (6); maintaining during said cooking step (b) within said oven (4) a vapor atmosphere having a molar fraction of water vapor of greater than or equal to 70 percent and a temperature of greater than or equal to 80 degrees Centigrade and less than or equal to 110 degrees centigrade, characterized in that prior to said unmolding step (c) active drying of a face (7) of plain bread is performed on said baked loaves (5), and during said step ( c) unmolding gripping means (8) acting on said pre-dried bread face (7) to extract a loaf (6) from each of said baked shaped loaves (5). Process according to Claim 1, characterized in that said active drying is carried out by exposing said exposed bread face (7) to a forced stream of hot air. Process according to Claim 2, characterized in that said forced hot air stream has a temperature of greater than or equal to 60 degrees centigrade and less than or equal to 80 degrees centigrade and a relative humidity of less than or equal to 10 percent. A method according to any one of claims 1 to 3, characterized in that said gripping means (8) act by applying an aspiration on said previously dried bread face (7). A device prepared for carrying out the industrial bread-making process according to claim 1, said device comprising a continuous feed oven (4), shaped bread conveyor (1) means (10) for baking through said oven (4), controlled means for injecting a water vapor flow into said oven (4) and means for measuring the thermodynamic conditions of the steam atmosphere in said oven (4), characterized in that it comprises means (9). ) active drying and gripping means (8) prepared to act on a face (7) of spot bread and a baked shaped bread (5). Device according to Claim 5, characterized in that said active drying means (9) comprise means for introducing a forced hot air stream and means for regulating the temperature and absolute humidity of said forced air stream. Device according to claim 5 or 6, characterized in that said gripping means (8) comprise suction means.