PRODUCTION PROCESS OF NIXTAMALIZED MAIZE FLOUR, NIXTAMALIZING THE MAIZE FRACTIONS TOGETHER WITHOUT PRODUCING NEJAYOTE

Abstract

The present invention “Production process of nixtamalized maize flour, nixtamalizing the maize fractions separately without producing nejayote”, considers the integration of the processes: Semi-humid milling of the maize (fractionated degerm), extruding of the maize fractions and milling-instant dehydration of the different nixtamalized and extruded maize fractions, has as novelty the way in which the nixtamalization process is carried out and the objective is to provide a nixtamalized maize flour production system that reduces the residues from the maize grain and completely eliminating nejayote production.

Claims

1. The process of nixtamalized maize flour production, nixtamalizing the maize fractions together without producing nejayote characterized in that it comprises the following stages: a) Clean the grains (1): In this stage, the maize grains pass between magnets, they're then winnowed, consecutively they're vacuumed, subsequently they're destoned, finally a color selection is done so that, afterwards, the clean maize grains are passed to the hydrate the grains stage. b) Hydrate the grains (2): In this stage, water is spread over the clean grains by spraying, they're left to rest for at least an hour, to then pass to the polish stage. c) Polish (3): In this stage of the process, the hydrated grains are polished and rested by a degerminator or grain polishing machine which polishes and separates the grain in two parts, the first one that is composed by fibers, pericarp, parts of the germ, and dark flours which we will call fiber fractions, the second part are the polished grains and endosperms which we will call endosperms, afterwards the endosperms pass to the nixtamalize stage while the fiber fractions pass to the dry fibers fractions stage. d) Dry fibers fractions (4): The fiber fractions are dried with a stream of hot air at a temperature range of 90° C. to 120° C. Afterwards, the fiber fractions pass to the sift fiber fractions stage. e) Sift fibers fractions (5): the dry fiber fraction is sifted to separate the pericarp and germ from the dark flours. The particles that pass through the sieve with a sieve opening of 0.71 mm to 0.85 mm are the dark flours fractions, the particles left on top of the sieve with a sieve opening of 0.71 mm to 0.85 mm are the pericarp and the germ, afterwards the particles left on top of the sieve pass to the mill pericarp and germ stage and the particles that pass through the sieve pass to the nixtamalize stage. f) Mill pericarp and germ (6): The pericarp and germ are milled in a hammer mill and sifted to obtain a particle size such that 95% of the particles pass through a sieve with a sieve opening of 0.25 mm, afterwards the milled pericarp and germ pass to the add milled germ and pericarp stage. g) Nixtamalize (7): A solution of calcium hydroxide of 0.1% to 0.15% in weight in relation to the endosperms, dark flours, and milled pericarp and germ (in the case that they are added as well) is hydrated by spraying. The temperature of the calcium hydroxide solution will be at a range of 80° C. to 85° C., afterwards it's left to rest for a period of two to four hours at a temperature of 40° C. to 45° C., the mixture acquires a humidity range between 25% and 32%. Afterwards, the nixtamalized endosperms, dark flours, and, in the case that they were included, milled pericarp and germ pass to the extrude stage. h) Extrude (8): The nixtamalized endosperms and dark flours, and the nixtamalized milled pericarp and germ (if they were added) are subjected to a double screw extruder in a range of its capacity between 80 to 90%, at an input material temperature of 40° C. to 50° C. and an output material temperature of 60° C. to 70° C., the extruded materials (endosperm, dark flour, and milled pericarp and germ, if included) will be called extrudate. After this stage, the extrudate is milled and dehydrated. i) Mill and instantly dehydrate (9): In this stage, the extrudate is milled in a micro pulverizer mill. Afterwards, it's instantly dehydrated with a flux of hot air, at a temperature range between 200° C. and 400° C., this hot air is transported through a pipe in which the diameter is reduced decreasing its pressure and increasing its velocity, afterwards the section where the diameter is reduced meets a section where the pipe diameter increases and the air expands causing an instant drying of the milled mixture (venturi effect). Consecutively the milled dehydrated extrudate passes to the cool stage. j) Cool (10): The cooling is carried out until the milled dehydrated extrudate reaches a temperature between 30° C. and 35° C. by means of pneumatic transport using air at room temperature. Afterwards, milled germ and pericarp is added. k) Add milled germ and pericarp (11): By means of a volumetric dispenser or gravimetric 10% to 15% of the milled germ and pericarp in relation to the milled, dehydrated, and cooled extrudate is added. Afterwards it passes to the sift stage. l) Sift (12): The mixture of milled, dehydrated, and cooled extrudate and milled pericarp and germ is sifted, the sifting yields two fractions: the fine fraction and the coarse fraction. The fine fraction is the nixtamalized maize flour and it's sent to the store stage, while the sifted material that does not comply with the granulometric specifications is called coarse fraction and it's sent to the remill stage. m) Remill (13) The coarse factions that are separated by the sieve are sent to be remilled in a micro pulverizer mill and afterwards are sent to the sift stage, the nixtamalized flours that comply with the granulometric properties pass to the store stage. n) Store (14): The flours that are separated by the sieve are sent to be stored in a hopper or/and packaged in different presentations.

2. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage b) Hydrate the grains, in this stage water is spread over the grains to reach a uniform humidity between 14% and 18%, afterwards it's left to rest for a period of time between one and ten hours.

3. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage c) polish: the hydrated and rested grains can also be polished by a grain polishing machine.

4. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage c) polish: the fibers fractions that are composed of fibers, pericarp, parts of the germ, and dark flours represent between 20% to 35% of the total of the grain, while the polished grains and endosperms represent from 80% to 65% of the total of the grain.

5. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage c) polish, the operation of polishing is carried out by means of one of the following equipment: degerminator, grain polishing machine.

6. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage c) polish, the degerminator may utilize a sifting mesh that is cylindric or conic.

7. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage f) mill pericarp and germ: if the milled pericarp and germ is not sent to the add milled germ and pericarp stage, it may pass directly to the nixtamalize stage.

8. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage h) extrude, the extruder has three steps with the following temperatures: from 40° C. to 50° C. in the first zone, from 50° C. to 60° C. in the second zone, and from 60° C. to 70° C. in the third zone, and with an output hole size in the die of 40% to 70% of the equivalent area of the output section of the extruder.

9. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage h) extrude, the humidity of the extrudate fractions is at a range of 25% to 30%.

10. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage h) extrude, the extrudate is cut into small pieces of 0.1 mm to 7 mm, using a four-blade cutter.

11. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage h) extrude, after the extrudate is cut it's cooled to temperatures lower than 60° C.

12. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage h) extrude, the extruded and cut material may be cooled by means of a pneumatic process, cooling tunnel or ambient ventilation.

13. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage i) mill and instantly dehydrate, the milled mixture is dehydrated with a flux of warm air at a temperature range between 200° C. and 400° C.

14. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage i) mill and instantly dehydrate, the milled extrudate is dehydrated with a flux of warm air until reaching a humidity range of 7% to 11%.

15. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage l) sift, the milled, dehydrated, and cooled mixture of extrudate is sifted, and has the following granulometric properties: with a sieve opening of 0.60 mm no particle is retained, with a sieve opening of 0.354 mm a maximum of 1% is retained, with a sieve opening of 0.250 mm a maximum of 15% is retained, with a sieve opening of 0.177 mm a maximum of 80% is retained, and with a sieve opening of 0.150 mm a maximum of 6% passes through.

16. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage l) sift, a nixtamalized flour with the following characteristics is produced: dry color from 30% to 100% reflectance and humid color from 20% to 70% reflectance, while the humidity ranges between 6% to 12%, and pH ranges between 5 to 7.

17. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage l) sift, a flour with an efficiency of 1.7 kg to 2.5 kg of dough is produced.

18. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage n) store, the flours that are separated by the sieve are sent to be stored in different presentations of sacks of 20 kg or 22.7 kg.

19. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage n) store, the flours that are separated by the sieve are sent to be stored in different presentations of super-sacks of 500 kg or 1000 kg.

20. The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote in conformity with claim 1 characterized in that in stage n) store, the flours that are separated by the sieve are sent to be stored in different presentations of packages of 1 kg or 2 kg.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0006] FIG. 1 shows the flux diagram of the production process of nixtamalized maize flour, nixtamalizing the maize fractions together without generating nejayote.

DETAILED DESCRIPTION OF THE INVENTION

[0007] The production process of nixtamalized maize flour, nixtamalizing the maize fractions together without generating nejayote is represented in FIG. 1 and includes the following stages: [0008] a) Clean the grains (1): In this stage, the maize grains pass between magnets to eliminate metals, they're then winnowed to eliminate junk (pieces of leaves, lumps of dirt, and branches), consecutively they're vacuumed to eliminate dust, subsequently they're destoned through density difference, finally a color selection is done to the grains to eliminate the grains that do not comply with the color of the flour to be produced. Afterwards the clean maize grains pass to the hydrate the grains stage. [0009] b) Hydrate the grains (2): In this stage, water is spread over the clean grains by spraying and they're continuously mixed to reach a uniform humidity between 14% and 18%, later they are left to rest for a period of one to ten hours to then move to the polish stage. [0010] c) Polish (3): In this stage of the process, the hydrated grains are polished and rested by a degerminator or grain polishing machine which polishes and separates the grain in two parts, the first one that represents between 20% to 35% of the total grain and is composed by fibers, pericarp, parts of the germ, and dark flours which we will call fiber fractions, the second part are the polished grains and endosperms which we will call endosperms and represent between 65% to 80% of the total of the grain, the granulometry of the endosperms is the following: with a sieve opening of 5.6 mm (US #3.5) a maximum of 12% is retained, with a sieve opening of 4.75 mm (US #4) a minimum of 25% and a maximum of 40% is retained, with a sieve opening of 4 mm (US #5) between 40% to 55% is retained, with a sieve opening of 3.35 mm (US #6) from 2% to 8% is retained, and with a sieve opening of 3.35 mm (US #6) 1% passes through. The degerminator utilizes a rotor and a sifting mesh that can be cylindric or conic, the degerm occurs when the polished and hydrated grains are positioned inside the sifting mesh and the rotor moves the sifting mesh, the grain is separated by the friction made between the grain and the sifting mesh, separating the fibers, pericarp, parts of the germ and dark flours. Afterwards, the endosperms pass to the nixtamalize stage while the fiber fractions pass to the dry fibers fractions stage. [0011] d) Dry fibers fractions (4): The fiber fractions are dried with a stream of hot air at a temperature range of 90° C. to 120° C. Afterwards, the fiber fractions are sifted. [0012] e) Sift fibers fractions (5): the dry fiber fraction is sifted to separate the pericarp and germ from the dark flours, the particles that pass the sieve with a sieve opening range of 0.71 mm (US #25) to 0.85 mm (US #20) are the dark flours fraction, the particles left on top of the sieve with a sieve opening range of 0.71 mm (US #25) to 0.85 mm (US #20) are the pericarp and gem, afterwards the particles left on top of the sieve pass to the mill pericarp and germ stage and the particles that pass through the sieve pass to the nixtamalize stage. From stage a) clean the grains to e) sift fibers fractions is what's catalogued as semi-humid milling of the maize, and in its most important part the grain is moistened to be polished and degerm. [0013] f) Mill pericarp and germ (6): The pericarp and germ are milled in a hammer mill and sieve to obtain a particle size such that 95% of the particles pass through a sieve with a sieve opening of 0.25 mm (US #60). The milled pericarp and germ may pass to the nixtamalize stage or to the add milled germ and pericarp stage. [0014] g) Nixtamalize (7): A solution of calcium hydroxide of 0.1% to 0.15% in weight in relation to the endosperms, dark flours, and milled pericarp and germ (in the case that they are added as well) is hydrated by spraying. The temperature of the calcium hydroxide solution will be at a range of 80° C. to 85° C., afterwards it's left to rest for a period of two to four hours at a temperature of 40° C. to 45° C. In this manner, the mixture of endosperms, dark flours, and, whether or not they were included, milled pericarp and germ will be at a humidity range of 25% to 32% at the final of the nixtamalize stage. Afterwards, the nixtamalized mixture of endosperms, dark flours, and, in the case that they were included, milled pericarp and germ pass to the extrude stage. [0015] h) Extrude (8): The nixtamalized endosperms, dark flours, and milled pericarp and germ are subjected to a double screw extruder in a range of its capacity between 80 to 90%, at an input temperature of the nixtamalized materials of 40° C. to 50° C. and an output material temperature of 60° C. to 70° C. The extruder has three steps with the following temperatures: from 40° C. to 50° C. in the first zone, from 50° C. to 60° C. in the second zone and from 60° C. to 70° C. in the third zone. With an output hole size in the die of 40% to 70% of the equivalent area of the output section of the extruder. The nixtamalized and extruded endosperm, dark flours, and milled pericarp and germ will be called extrudate. The extrudate is cut in small pieces of 0.1 mm to 7 mm, using a four-blade cutter. After the extrudate is cut it's cooled to temperatures lower than 60° C. The cooling can be carried out by means of a pneumatic process, cooling tunnel or ambient ventilation. The humidity of the extrudate is at a range of 25% to 32%. The novelty of this invention lies in the nixtamalization method, which is the combination of the steps described as g) nixtamalize and h) extrude. Being that, in the stages of nixtamalization, altogether, of the endosperms, dark flours, and fibers fraction (milled pericarp and germ), the hydration of the starches in the presence of food grade lime is achieved and in the extrude stage the transformation of the same starches is completed, which results in properties such as the texture, aroma and taste of the doughs and tortillas, similar to those of traditional nixtamalization. After this stage the extrudate is milled and instantly dehydrated. [0016] i) Mill and instantly dehydrate (9): In this stage, the extrudate is milled in a micro pulverizer mill. Afterwards, it's instantly dehydrated with a flux of hot air (Venturi effect), at a temperature range between 200° C. and 400° C., this hot air is transported through a pipe in which the diameter is reduced decreasing its pressure and increasing its velocity (Venturi effect), afterwards the section where the diameter is reduced meets a section where the pipe diameter increases and the air expands causing an instant drying of the milled mixture, this effect is known as venturi. Until the milled and dehydrated extrudate has a humidity between 7% to 11%. Consecutively the milled dehydrated extrudate passes to the cool stage. [0017] j) Cool (10): The cooling is carried out until the milled dehydrated extrudate reaches a temperature between 30° C. and 35° C. by means of pneumatic transport using air at room temperature. Afterwards it passes to the add milled germ and pericarp stage. [0018] k) Add milled germ and pericarp (11): By means of a volumetric dispenser or gravimetric 10% to 15% of the milled germ and pericarp in relation to the milled, dehydrated, and cooled extrudate is added. Afterwards it passes to the sift stage. [0019] l) Sift (12): The mixture of milled, dehydrated, and cooled extrudate and milled pericarp and germ is sifted, the sifting yields two fractions: the fine fraction and the coarse fraction. The fine fraction is nixtamalized maize flour and has the following granulometric properties: with a sieve opening of 0.60 mm (US #30) no particle is retained, with a sieve opening of 0.354 mm (US #45) a maximum of 1% is retained, with a sieve opening of 0.250 mm (US #60) a maximum of 15% is retained, with a sieve opening of 0.177 mm (US #80) a maximum of 80% is retained, and with a sieve opening of 0.150 mm (US #100) a maximum of 6% passes through. The color characteristics of the nixtamalized maize flour are the following: dry color from 30% to 100% reflectance and humid color from 20% to 70% reflectance, while the humidity ranges between 6% to 12%, and pH ranges between 5 to 7. The efficiency of the nixtamalized flour refers to the amount of dough that is obtained by adding water to one kilogram of flour. This efficiency ranges from 1.7 kg to 2.5 kg of dough. The sifted material that does not comply with the granulometric properties will be called coarse fraction and is sent to the remill stage. [0020] m) Remill (13): The coarse factions that are separated by the sieve are sent to be remilled in a micro pulverizer mill and afterwards are sent to the sift stage, the nixtamalized flours that comply with the granulometric properties pass to the store stage. [0021] n) Store (14): The flours that are separated by the sieve are sent to be stored in a hopper or/and packaged in different presentations such as sacks (20 kilograms or 22.7 kilograms), super-sacks (500 kilograms or 1000 kilograms), package (1 or 2 kilograms).

Use Cases:

[0022] Following the production process of nixtamalized maize flour, nixtamalizing the maize fractions together without producing nejayote, in the clean the grains stage, 1000 kg of white maize grains were cleaned to which metals were removed by passing it through two magnets, afterwards it was winnowed and vacuumed to eliminate junk, coarse and fine impurities. Afterwards, the clean maize grains pass to the stage of hydrate the grains. In the hydrate the grains stage water is sprayed, and it was continuously mixed to reach a uniform humidity of 15% to 218%, then they are left to rest for at least one hour, to then pass to the stage of polish. The hydrated and rested grains were polished using a polishing-degerminator machine. Two fractions were obtained: 1. Polished grains and endosperms (endosperm), 2. Mixture of pericarp, germ and dark flours (fibers fraction), the fibers fraction is dried in a stream of hot air (90° C. to 110° C.) at a maximum of 10% humidity, then the sifting takes place to separate the pericarp and the germ form the fark flours, the particles that pass through with a sieve opening of 0.71 mm (US #25) to 0.85 mm (US #20) were the dark flours fractions, the particles left on top of the sieve opening of 0.71 mm (US #25) to 0.85 mm (US #20) were the pericarp and germ. Afterwards the particles that were left on top of the sieve passed to the mill pericarp and germ stage and the particles that passed through the sieve (dark flours) passed to the nixtamalize stage. Then the pericarp and germ were milled in a hammer mill and sifted to obtain a particle size so that 95% passes through a sieve opening of 0.25 mm (US #60). After milling the pericarp and germ, next was the nixtamalize stage where the endosperms, dark flours, and milled pericarp and germ were hydrated by spraying with a calcium hydroxide solution of 0.1% to 0.15% in weight in relation to the endosperms, dark flours, and milled pericarp and germ; the temperature of the solution was ranging between 80° C. and 85° C. Afterwards, it was left to rest for a period of two to four hours at a temperature of 40° C. to 45° C. The nixtamalized materials were subjected to a double screw extruder at a range of its capacity between 80% to 90%, at an input material temperature of 40° C. to 50° C. and an output material temperature of 60° C. to 70° C. The extruder had three steps with the following temperatures: 40° C. to 50° C. in the first zone, 50° C. to 60° C. in the second zone, and 60° C. to 70° C. in the third zone. With an output hole size in the die of 40% to 70% of the equivalent area of the output section of the extruder. The extrudate was then cut into small pieces of 0.1 mm to 7 mm, with a four-blade cutter. After the extrudate was cut, it was cooled to temperatures below 60° C. The cooling took place by pneumatic conveying using room temperature air. The humidity of the extrudate was at a range of 25% to 30%. The extrudate was milled in micro pulverizer mills, and it was then instantly dehydrated with a flow of hot air at a temperature range of 200° C. to 400° C., this hot air was transported through a pipeline in which the diameter was reduced decreasing its pressure and increasing its velocity (Venturi effect). Until the milled and dehydrated extrudate had a humidity ranging between 7% and 11%. Afterwards, the milled and dehydrated extrudate passed to the cool stage, the cooling took place until the milled and dehydrated extrudate reached a temperature between 30° C. and 35° C., by means of a pneumatic conveyor using room temperature air. By means of a volumetric dispenser, 10% to 15% of milled germ and pericarp in relation to the milled, dehydrated, and cooled extrudate were added. Afterwards, the mixture of milled, dehydrated, and cooled extrudate with milled pericarp and germ passed to the sifting process where the flour had the following granulometric characteristics: with a sieve opening of 0.60 mm (US #30) no particles were retained, with a sieve opening of 0.354 mm (US #40) a maximum of 1% was retained, with a sieve opening of 0.250 mm (US #60) a maximum of 15% was retained, with a sieve opening of 0.177 mm (US #80) a maximum of 80% was retained, and with a sieve opening of 0.150 mm (US #100) a maximum of 6% passed through. The flours that did not comply with the specified granulometry were sent to the remill stage, in micro pulverizer mills, and were integrated to the sifting. The color characteristics of the produced flour were the following: dry color of 84% reflectance and humid color of 40% reflectance, while the humidity was at 7% and pH at 6.3. The efficiency of the flour to dough obtained adding water to one kilogram of flour was 2.25 kilograms of dough.