RU2661200C1 - Method for producing porous tablets of milk sugar and device for its implementation - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: invention relates to food industry. Method for producing porous tablets of milk sugar includes degreasing the whey, separating the casein particles, ultrafiltration, nanofiltration for partial demineralization and concentration, electrodialysis desalination to a mineral content of 0.04 %, thickening in a vacuum evaporator to 60–65 % solids, crystallization of lactose from supersaturated syrups, washing with water at a temperature of 5–6 °C, separating the lactose crystals to a moisture content of 7–10 %, wherein the formation of the porous tablets in the matrix is carried out using a device for producing porous tablets of milk sugar in two steps, at the first stage, the molding is due to vibration, in the second stage, the top layer of the tablet is rubbed into the matrix, drying and cooling of the porous tablets.

EFFECT: invention allows to minimize the number of technological operations, as well as to improve the disintegration of tablets in water.

3 cl, 2 dwg, 4 ex

Description

FIELD OF THE INVENTION

The method of obtaining porous tablets and a device for its implementation relate to the production of dry milk products, namely, technology and equipment for the production of porous tablets of milk sugar, and can be used in enterprises of the milk processing industry.

In addition to milk sugar, in this way and on such a device, dry protein-free whey, dry demineralized whey, desalted by electrodialysis, and other dry porous tablets (briquettes) with an increased lactose content can be obtained by varying the ratios of the prescription components and the degree of dehydration of the molding mixture.

State of the art

The known method and production line for the production of whey products, including a whey tank, connected by a pipeline during the technological process, a centrifugal separator for separating milk fat and casein dust from the whey, containers for skim whey, albumin milk, clarified whey and molasses, skim heater whey, serum albumin boiling unit, vacuum evaporation thickener, crystallizer, centrifuge for separation of crystalline mass milk sugar and a dryer for producing crystalline powder (see RF patent for the invention No. 2100438 "Technological line for the production of whey products" - Application. 07/18/1995, class IPC C05K 5/00, A23C 21/00, publ. 27.12 .1997).

The well-known production line allows you to produce dry products with a high content of lactose, mainly milk sugar, but the low degree of purification from protein and mineral substances does not allow to obtain a high-quality product.

Known devices that provide a high degree of purification of lactose-containing raw materials from protein and mineral substances before crystallization of lactose (Khramtsov A.G. Milk sugar. - M .: Agropromizdat, 1987. - 224 p.). On p. 168, fig. 7.26, a milk sugar production line is described, where installations for deep purification of whey by molecular sieve filtration and demineralization by electrodialysis, followed by crystallization of lactose, separation of the crystals in a centrifuge from molasses, drying and packing of crystalline powder are presented.

A well-known production line allows the production of high-quality milk sugar, but part of the dry matter of milk raw materials is lost in the form of lactose dust and small crystals of milk sugar, which are captured by waste heat carrier (air) during drying and emitted from the dryer into the surrounding atmosphere, and the resulting crystalline powder does not differ a variety of structural and mechanical properties and forms.

A known method of producing whey in granules (see RF patent for the invention No. 2144774, class IPC A23C 21/00, A23C 1/00, publ. 01/27/2000), in which the whey is concentrated to a mass fraction of solids of 48-52 %, carry out structure formation in two stages. At the first stage, proteins and lactose are structured by heating and cooling the condensed product; at the second stage, structure formation is carried out to a mass fraction of solids of 54-58% and a viscosity of 65-75 MPa⋅s. The wet product is compacted by pressing, followed by drying with air to a mass fraction of solids of 82-92%, and granulation is carried out by crushing the pressed mass. The resulting dry product due to pressing has high mechanical strength and requires crushing before molding granules.

According to the technical nature of the closest prototype by the method of obtaining porous tablets of milk sugar is not found.

Known devices for pressing powders, providing the adhesion of particles of granular granular material into aggregates in the form of tablets (briquettes) using pressure or using additional binding material. However, when powders are pressed under pressure, a large amount of suspended dust is formed, which worsens working conditions, the environmental situation, and increases product losses at various stages of the production of tablets (briquettes).

The literature describes devices for pressing powders, providing the binding of particles of granular granular material into aggregates in the form of tablets (briquettes) using a binding material (or liquid). A device that is close in technical essence is a tablet machine with a feed hopper and a granulator, where the product is pre-compacted (see p. 61-62, Machikhin Yu.A., Zurabishvili GG Tableting of food materials. - M.: Food industry . - 1978. - 135 p.). The dry powder intended for tabletting enters the hopper loading device and enters the moving conveyor belt, which has a corrugated profile. Using the damper, the height of the powder layer on the conveyor belt is regulated. Sealing takes place between the roller and the conveyor, and then the pressed material enters the secant knives, rotating in opposite directions, and the briquettes are crushed. Using an electric vibrator, the compacted material is completely knocked out of the cells of the conveyor belt. The crushed material of the briquettes enters the matrix located in the table of the tablet machine, and with the help of pressing punches provides the formation of tablets under pressure.

A device for pressing tablets is known (see AC No. 632583. Device for pressing tablets / Zurabishvili G.G., Machikhin Yu.A., Nadareishvili G.I., class IPC B30B 11/18, B30B 3/00, publ. BI No. 42, 11/15/1978), which by technical solution is the closest to the claimed device in terms of the essential features (prototype).

According to the prototype, the device includes loading funnels, in some of which food material is poured, and in other binding material for forming the body of the tablet and connecting with the outer layers. A conical screw is located in the central part of the feed hopper. Under the loading funnels in which the food material is located, there are two horizontally located flexible forming tapes with cells on the outer surfaces, enveloping the drive and driven rolls. Vibrators are located between the flexible forming tapes. Pressing rollers are in contact with flexible tapes, on the working surface of which there is a mesh knurling with an angle of 30-45 ° between the depressions. The operation of the device is as follows. From feeding hoppers with food material, powder is supplied to flexible tapes with cells. With further movement of the tapes by vibrators, the food material is pre-compacted in the cells before pressing. Further compaction of the material in the cells occurs between the guides and the press rolls. The embossed profile of the press rolls is necessary to improve the bonding between the tablet layers and the binder material coming from another funnel using a conical screw. The compressed material thus compacted is fed by molding tapes into the working area between the two press rolls, where the final pressing of the tablets takes place.

Disclosure of invention

The objective of the invention is to provide a method and device for producing porous tablets (briquettes) of milk sugar, which would minimize the number of technological operations in the production process and improve the disintegration of tablets in water.

The technical result of the invention is to minimize the number of technological operations in the process of obtaining porous tablets of milk sugar, as well as improving the disintegration of tablets in water.

The specified technical result is achieved due to the fact that the method of producing porous tablets of milk sugar includes the degreasing of whey, separation of casein particles, ultrafiltration, nanofiltration for partial demineralization and concentration, electrodialysis desalination to a level of 80-90%, condensation in a vacuum evaporator up to 60 -65% solids, crystallization of lactose from supersaturated syrups, washing with water at a temperature not exceeding 60 ° C, separation of lactose crystals to a moisture content of 7-10%, and molding tablets in the matrix is carried out in two stages, the first stage is a molding by its own weight and vibration of wet crystals, the second stage occurs massaging the upper layer into matrix tablets, drying and cooling of porous tablets.

The specified technical result is also achieved due to the fact that the device for producing porous milk sugar tablets includes a loading hopper, a horizontal feeder, a flexible forming tape with cells on the outer surfaces, envelope driving and driven rolls, vibrators for preliminary compaction of the material in the matrix cells and tablet formation moreover, according to the invention, the forming tape is made double, its upper part is made of a release material, and the lower part of the material is free to pass air, on the bracket is fixed a transverse row of elastic rubbing spatulas with the ability to adjust the gap between the lower edge and the flexible forming tape, a section for drying and cooling the tablets.

For greater safety, the design of the device may be covered by a casing.

To solve this problem, a device is proposed in the milk sugar production line that provides the production of porous tablets (briquettes) without the use of pressure pressing.

The advantages of the proposed device are to minimize the number of technological operations when obtaining porous tablets of milk sugar after centrifugal decantation of the crystalline mass through the use of residual moisture crystals (up to 10%), where molasses or rinse water acts as a binding material, and also to improve the disintegration of the tablets in water . As a measured parameter, the disintegration time of the porous tablets in seconds is controlled when immersed in water at a certain temperature.

Brief Description of the Drawings

In FIG. 1 shows a diagram of a device for producing porous tablets of milk sugar.

In FIG. 2 shows a photograph of wet crystals of food and pharmacopeia lactose and porous tablets.

The following notation is used in the figures: 1 — loading hopper, 2 — horizontal feeder, 3 — upper part of the forming tape, 4 — lower part of the forming tape, 5 — drive roll, 6 — driven roll, 7 — material pre-vibrators, 8 — elastic spatulas, 9 - duct for supplying warm air, 10 - duct for cooling, 11 - duct for exhaust air, 12 - vibrator for forming tablets, 13 - receiving hopper of the pneumatic transport system, 14 - casing.

The implementation of the invention

The proposed device consists of a loading hopper 1 for wet lactose crystals, a horizontal feeder 2, including movable multi-blade agitators, the axis of which is horizontally above a flexible double forming tape 3, 4, almost touching (up to 5 mm) its lower edge of its blades. When the agitators rotate, the material uniformly with a thin layer enters the flexible forming conveyor belt, the upper part 3 of which is made of a polymer release material and in which there are matrices, the lower part of the tape 4 has a finely perforated (up to 50 μm) surface. The tension of the flexible double tape is carried out by the leading 5 and driven 6 rolls. Between the flexible forming tapes 3 and 4, vibrators 7 are located, which, at the first stage, “softly” fill the matrices with material. At the second stage, the final molding of the porous tablet in the matrices takes place due to the row of elastic spatulas 8 mounted on the bracket located across the flexible tape and rubbing the upper layers of the wet material into the filled matrices. Matrices are flat-cylindrical with a height / diameter ratio of 0.3 / 1.0. This shape and aspect ratio of the tablets contributes to a more free exit of the formed tablet from the matrix after drying. The thickness of the layer of the dried product affects the heating, and in the case of pressure-compressed tablets in the center of the tablet, heat transfer occurs due to heat conduction, therefore, the heating rate decreases and, accordingly, the drying time increases. The drying of the formed porous tablets takes place inside the matrices of the flexible tape due to the supply of warm air through the duct 9. In the proposed device due to the molding of the porous structure using the method of rubbing wet material into the matrix without applying compression pressure, heat transfer in the entire volume of the tablet is carried out by convective heat transfer increases the heating rate and intensifies the drying process of tablets. At the next stage, dry porous tablets located in the matrices of the flexible tape are cooled with purified air with a low moisture content at room temperatures of 20-24 ° C through the duct 10. The exhaust air after drying and after cooling is removed through a common duct 11. The flexible tape goes around the drive roll 5 and is exposed to a vibrator 12, as a result of which dry porous tablets fall out of the matrix into the receiving hopper 13 of the pneumatic transport system and are sent to the packaging. For greater safety, the design of the device can be closed by a casing 14.

It is known that the forces of ejection of tablets from a steel matrix are 27-29% higher than the forces of ejection from a matrix made of plexiglass and polymeric materials, therefore a release material is used for the tape in which the matrices are made. The resulting porous tablets change the adhesive properties, since the adhesion between the matrix wall and the side surface of the tablet decreases. The porous structure allows to reduce contact with the inner surface of the matrix, respectively, to reduce the friction (coefficient of friction) of the side surface of the tablet on the matrix wall, so it is much easier to release dry tablets from the matrix during unloading.

In the formation of porous tablets, vibration is applied, i.e. matrix filling occurs “softly” due to the dead weight of wet crystals, i.e. at minimum pressure. In the proposed device, tablet molding takes place in two stages: at the first stage, it occurs only due to gravitational forces; on the second - due to the efforts of an elastic spatula to rub the wet mass of crystals into the matrix. Thus, if we talk conditionally about the coefficient of pressing, then in the proposed device it is almost close to zero.

The influence of particle size distribution on the molding process is determined by the specific surface area of the crystals, which depends on the linear dimensions of the crystals of milk sugar. The number of contacts between them depends on the specific surface area of the crystals, and consequently, the adhesion force between the crystals during rubbing into matrices, as well as the amount of retained liquid film (molasses or wash water) on the faces of the crystals and “trapped” air during molding, which ultimately affects the drying speed of the porous tablets. All of the above affects the disintegration of porous tablets in water, which is significantly better than that of pressure-compressed tablets, according to the prototype. As the measured parameter, the disintegration time (in seconds) of the tablets at a certain temperature in water is used.

In the future, the method of obtaining porous tablets of milk sugar using the proposed device is illustrated by a description of specific options for its implementation and the presented graphic drawing (Fig. 1), which schematically shows the device.

To describe a specific variant of the method for producing porous tablets and the implementation of the device, we consider the sequence of technological operations for producing milk sugar in the form of porous tablets. In accordance with the analogue, deep purification of dairy raw materials by molecular sieve filtration is used (baromembrane methods): at the first stage, milk proteins are isolated by ultrafiltration; in the second stage, mineral salts are partially removed by nanofiltration by 25-30% and at the same time the solution is concentrated to 20-22% solids. Subsequently, at the third stage, the electro-membrane method — electrodialysis — is used and deep permeate (filtrate) demineralization is carried out after treatment with ultrafiltration and nanofiltration to a desalination level of 80-90%. As a result of such a deep purification of raw materials by membrane methods from protein and mineral substances, the concentration of the concentrated demineralized permeate is reduced to 18-20% dry matter. Next, the resulting permeate is concentrated in a vacuum evaporator to a concentration of 60-65% dry matter at a temperature of 60-70 ° C. The supersaturated syrup is sent to a crystallizer-cooler, where lactose crystallizes when the temperature drops to 4-6 ° C with constant stirring. The finished crystallized milk sugar is separated in a centrifugal decanter into crystals and molasses (intercrystal liquid). Given the deep purification of the feedstock by molecular sieve filtration and electrodialysis, molasses is separated during decantation and the crystals are washed once with cold water at a temperature of 4-6 ° C. The moisture content of the crystals is 7-10% and moisture is distributed in the form of a film on the surface of the crystals. Wet lactose crystals enter the hopper 1 of the proposed device, through the agitators 2 they are uniformly fed to the surface of the flexible tape 3, they fill the matrices and are exposed to the vibrator 7. The flexible tape moves to the bracket with the transverse row of elastic spatulas 8, where the matrices pre-filled with wet material under the action of a vibrator 7, rubbing the upper layer of wet crystals. The flexible tape moves to section 9, where the porous tablets are first dried and then cooled in section 10, from where the formed dried porous tablets move to the roll 5. Due to the bending of the roll 5 and the action of the vibrator 12, the porous tablets are unloaded. Dry porous tablets fall out of the matrix into the receiving hopper 13 of the pneumatic transport system and are sent to the packaging (see Fig. 2 - photo of the tablets).

Examples of specific performance of the method for producing milk sugar in the form of porous tablets are given below.

Example 1. Milk whey in an amount of 100 kg with a content of 6.2% solids, 0.8% protein, 0.7% minerals is sent to ultrafiltration. The resulting permeate (filtrate) in the amount of 92 kg with a content of 5.4% solids, 0.14% non-protein nitrogen, 0.73% minerals is concentrated on a nanofiltration unit to 22% dry solids and desalted to a mineral content of 0.54% . After nanofiltration, the treated permeate in an amount of 23 kg is sent to an electrodialysis unit and demineralization is carried out to a mineral content of 0.04%. The demineralized permeate is concentrated in a vacuum evaporator at a temperature of 65 ° C to a content of 65% solids. Condensed syrup in the amount of 7.3 kg is sent to a crystallizer-cooler, where the solution temperature is gradually reduced to 6 ° C with constant stirring. After crystallization, lactose crystals are separated in a decanter and washed with cold water at a temperature of 6 ° C. Wet crystals in the amount of 5.8 kg with a moisture content of 10% are sent to the installation for forming porous tablets and receive 5.42 kg of dry porous tablets. The disintegration of porous tablets was 54 seconds in water at a temperature of 22 ° C.

Example 2. Milk whey in an amount of 100 kg with a content of 6.0% solids, 0.7% protein, 0.7% minerals is sent for ultrafiltration. The resulting permeate (filtrate) in an amount of 92 kg with a content of 5.2% solids, 0.15% non-protein nitrogen, 0.72% minerals is concentrated on a nanofiltration unit to 23% dry solids and desalted to a mineral content 0.50% . After nanofiltration, the treated permeate in an amount of 22 kg is sent to an electrodialysis unit and demineralization is carried out to a mineral content of 0.04%. The demineralized permeate is concentrated in a vacuum evaporator at a temperature of 64 ° C to a content of 64% solids. Condensed syrup in the amount of 7.1 kg is sent to a crystallizer-cooler, where the temperature of the solution is gradually reduced to 5 ° C with constant stirring. After crystallization, lactose crystals are separated in a decanter and washed with cold water at a temperature of 5 ° C. Wet crystals in the amount of 5.7 kg with a moisture content of 7% are sent to the installation for forming porous tablets and receive 5.3 kg of dry porous tablets. The disintegration of porous tablets was 46 seconds in water at a temperature of 22 ° C.

Example 3. Milk whey in an amount of 100 kg with a content of 6.2% solids, 0.8% protein, 0.7% minerals is treated with membrane methods in the same way as in example 1. From wet crystals obtained in an amount of 5.8 kg, 0.8 kg of material with a moisture content of 10% is selected and tablets are pressed on a laboratory press, followed by drying of the tablets with air to a moisture content of 0.6%. The disintegration of the tablets was 306 seconds in water at a temperature of 22 ° C.

Example 4. Milk whey in an amount of 100 kg with a content of 6.0% solids, 0.7% protein, 0.7% of mineral substances is treated with membrane methods in the same way as in example 2. From wet crystals obtained in an amount of 5.7 kg, 0.5 kg is taken and dried to a moisture content of 6%. Lactose crystals in an amount of 0.5 kg with a moisture content of 6% are sent to the installation for forming porous tablets. After molding and drying, the porous tablets disintegrate upon removal from the matrix.

A comparative analysis of the claimed invention showed that the set of essential features of the claimed method and device is not known from the prior art and, therefore, meets the condition of patentability "Novelty".

In the prior art there were no signs that coincided with the distinguishing features of the claimed invention and affecting the achievement of the claimed technical result, therefore, the claimed invention meets the patentability condition "Inventive step".

The above information confirms the possibility of using the proposed method and device for producing porous tablets of milk sugar, can be used at enterprises of the milk processing industry and therefore meets the patentability condition "Industrial Applicability".

Claims (3)

1. A device for producing porous tablets of milk sugar, including a loading hopper, a horizontal feeder, a flexible forming tape with cells on the outer surfaces, envelope leading and driven rolls, vibrators for preliminary compaction of the material in the cells of the matrix and the formation of tablets, characterized in that the horizontal feeder includes movable multi-vane agitators, the forming tape is double, its upper part is made of release material, and the lower part is free-flowing material skating air, moreover, the matrix of the forming tape has a height to diameter ratio of 0.3 / 1.0, a transverse row of elastic rubbing spatulas is fixed on the bracket with the possibility of adjusting the gap between the lower edge and the flexible forming tape, and a section for drying and cooling the tablets. 2. The device according to p. 1, characterized in that the design of the device is closed by a casing. 3. A method of obtaining porous tablets of milk sugar, including the degreasing of whey, separation of casein particles, ultrafiltration, nanofiltration for partial demineralization and concentration, electrodialysis desalination to a mineral content of 0.04%, condensation in a vacuum evaporator to 60-65% dry substances, crystallization of lactose from supersaturated syrups, washing with water at a temperature of 5-6 ° C, separation of lactose crystals to a moisture content of 7-10%, and the formation of porous tablets in a matrix is carried out using Using the device according to claim 1 in two stages, at the first stage, the molding is carried out by vibration, at the second stage, the upper layer of the tablet is rubbed into the matrix, drying and cooling of the porous tablets.

Images