Protein product obtained from brewer's grains and its production method
11712048 · 2023-08-01
Assignee
Inventors
Cpc classification
A23K20/147
HUMAN NECESSITIES
Y02P60/87
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
Abstract
The present technology generally relates to food-processing industry, namely to a method of processing brewer's grains. The invention enables to increase the level of extracted food fractions of brewer's grains up to 90-95% and to increase protein content in barley protein concentrate up to 50-65% wt (dry solid). The method implies that brewer's grains are subject to loosening by means of a vibrating screen, grinding in a colloid mill with addition of water or centrate in the ratio from 0.5:1 to 1:1 to brewer's grains in order to produce a pasty homogeneous mass from brewer's grains; and then this mass is subject to processing by means of a screw extractor for its further grinding and division into 2 factions: suspension with the humidity level of 90-95%, and ground husk of brewer's grains with the humidity level of 60-75% suitable for its further industrial use. Then the suspension is supplied to mechanical filtration in order to remove the ground husk, pumped into the container and dried in order to obtain the humidity level of max. 7%.
Claims
1. A method for producing a protein concentrate having a moisture content equal to or less than 7%, and comprising proteins, fats, fibre and ash; wherein the protein concentrate has a protein content of at least 55% wt with preservation of biological activity, the method comprising: i) loosening-up brewer's grains to obtain a homogeneous mass; ii) removing mechanical impurities from the homogeneous mass; iii) subjecting the homogeneous mass to grinding, by a colloid mill, with addition of water or centrate to produce a pasty mass having: a moisture content of between 90 and 95%, and a particle size of between 0.1 mm and 0.9 mm, and wherein: the addition of the water or the centrate is for homogeneous humidification of the pasty mass in a volume; the pasty mass has a viscosity of between 750 cPa.Math.s and 1400 cPa.Math.s that moves by gravity to a screw extractor where the pasty mass is subject to additional grinding and separation to produce a suspension with a viscosity of between 1.5 and 3 cPa.Math.s; iv) subjecting the suspension of step iii) to vibrating filtration and drying to obtain the protein concentrate having the moisture content equal to or less than 7% and the protein content of at least 55% wt.
2. The method of claim 1, wherein a rotor speed of the colloid mill is between 1,800 rot./second and 3,200 rot./second.
3. The method of claim 2, wherein the water or centrate is supplied to a receiving bunker of the colloid mill via openings of a water pipeline located around a circumference of the receiving bunker in its upper part.
4. The method of claim 1, wherein step i) and step ii) are performed by means of a vibrating screen having an average hole size of between 6 mm and 10 mm, and a screen vibration frequency of between 10 Hz and 50 Hz and an amplitude of between 2 mm and 20 mm.
5. The method of claim 1, wherein the vibrating filtration is performed with screens having an average hole size of between 0.2 mm and 0.6 mm to remove remaining husk particles.
6. The method of claim 1, wherein the drying is performed in a spray-type drier or in a vacuum-type drier.
7. The method of claim 6, wherein the drying in the spray-type drier is performed for a period of between about 8 hours and 10 hours at a temperature equal to or less than 200° C.
8. The method of claim 6, wherein the drying in the vacuum-type drier is performed for a period of between 8 hours and 10 hours at a temperature equal to or less than 80° C.
9. The method of claim 8, further comprising grinding the dried protein concentrate to obtain a powder having an average particle size equal to or less than 0.1 mm, wherein, before drying in the vacuum-type drier, the suspension is subjected to decanting to achieve a moisture content equal to or less than 60%.
10. The method of claim 3, wherein openings in the water pipeline are uniformly spaced along its length in order to ensure the homogeneous humidifying of the pasty mass.
Description
BRIEF DESCRIPTION OF DRAWINGS
(1) All features of embodiments which are described in this disclosure are not mutually exclusive and can be combined with one another. For example, elements of one embodiment can be utilized in the other embodiments without further mention. A detailed description of specific embodiments is provided herein below with reference to the accompanying drawings in which:
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EMBODIMENT OF THE INVENTION
(5) Below is a more detailed description of the claimed invention that does not limit the scope of the claimed invention but demonstrates implement ability of the invention by means of achieving the claimed technical result.
(6) Initial brewer's grains with the humidity level of between about 70 and 90% are subject to processing in the course of 3 hours after they are produced (from the moment they are obtained as a waste product of the brewing industry). The temperature of such brewer's grains as soon as it arrives from the production facility varies from between about 2° C. and about 80° C. The brewer's grains are loaded manually or by means of any mechanical method on a vibrating screen 1 (
(7) Grinding of the brewer's grains in the colloid mill 3 takes place in the shell 21 between working surfaces of the rotor 20 and the stator 19, for example, in the course of rotation of the mill's rotor 20 at the rate of 1,800-3,200 rot./second what enables to produce thick, homogeneous, but sloppy consistency of the pulp for the maximum extraction of a nutritional fraction from the initial raw material at the screw extraction stage. It is preferable to use centrate produced in the course of the suspension's further processing (in case of its concentrating) in the colloid mill 3 instead of water as this may provide better extraction of the nutritional fractions remained in the centrate and may prevent disposal of the centrate before it is discharged to the sewerage system.
(8) Water or centrate from blocks 5 or 12 is supplied to the V-shaped tank (receiving bunker) 23 of the colloid mill 3 via openings 14 of the water pipeline 13 located around the circumference of the tank in its upper part above the mark indicating the maximum tank load with raw materials. Amount of the supplied water or centrate can be regulated by means of the valve 18. In some instances, the openings 14 in the pipeline are uniformly spaced along its length in order to ensure the homogeneous humidifying (thinning) of the brewer's grains during the course of processing.
(9) After grinding in the colloid mill 3 the pulp is treated in the screw extractor 5 with the screw rotation rate from 2 rot./minute up to 8 rot./minute to quickly (e.g., within 1-2 seconds) separate the food suspension from a waste product, barley's husk. To this end, the pasty mass (pulp) produced by the colloid mill 3 goes (fell by gravity) to the screw extractor 5 where it is separated from the husk in order to produce suspension having a humidity level equal to or less than 95%, and a waste product, barley's husk with a humidity level of between about 60% and about 75% and an average husk particle size of between about 1.0 mm and about 5.0 mm. After the treatment in the screw extractor 5, the suspension may contain between about 2% and about 5% of small husk particles having an average particle size ranging from between about 0.01 and about 1.0 mm. This suspension (with the impeller or another pump 6 designed for work with suspension with the impurity level of up to 5% represented by small fractions of max. 1.0 mm) goes to the next purification stage—vibration filter 7 with the filter holes of between about 0.2 mm and about 0.5 mm. That process practically guarantees complete removal of remaining husk in the suspension after the screw extraction stage. After the vibration filter 7 the suspension is pumped to the collection tank 9 by means of the impeller pump 8. The produced protein suspension can be the final product that can be used as a food or feed supplement and it can also be frozen for its further use. The produced protein suspension can be sent for its further processing treatment to the block 11 for the purpose of obtaining a protein product (concentrate) with the humidity level of equal to or less than 7%, with the particle size of equal to or less than 0.1 mm, preferably 0.05 mm and with protein content between about 50% wt and about 65% wt. For this purpose, the obtained suspension is dried in a spray-type drier in the course of 8-10 hours at the temperature of max. 200° C. or in a vacuum-type drier in the course of 8-10 hours at the temperature of 80° C. Therewith before vacuum drying the suspension undergoes decanting in order to obtain humidity level equal to or less than 60%. The obtained pasty mass is dried and the obtained dry product (protein concentrate) in the form of granules having an average particle size 0.1-5 mm is subject to additional grinding in order to produce particles with the diameter of equal to or less than 0.05 mm.
(10) Husk is a waste product of the brewer's grains processing and in the course of the screw extractor's operation husk naturally falls in the collection bunker from where it is delivered to the collection tank 10 by means of a screw conveyor, or a spiral conveyor or any other conveyor. The described production line can be used for producing barley protein concentrate with protein content of less than 50% wt, for example 40, 42, 47 and 49% wt (with a lower energy value) in case of respective settings of devices. Such product can be used in fields where there are no requirements to achieving the greatest possible quantitative content of protein in a protein product, for example, when it is used as animal food stuff.
(11) The examples below are presented to illustrate the practice of various embodiments of the present disclosure. They are not intended to limit or define the entire scope of this disclosure. The disclosure is not limited to the particular embodiments described and illustrated herein but includes all modifications and variations falling within the scope of the disclosure as defined in the appended embodiments.
Example 1. Production of Protein Barley Concentrate
(12) 260 kg of brewer's grains with the humidity level of 75.59% (original composition, energy value of 150 kcal) were manually loaded on the vibrating screen 1 represented by the vibrating table unit XFZ1020 with a single-level screen and 10 mm holes, with the table unit length of 2,000 mm, with the table unit width of 1,000 mm, with the vibration frequency of 20 Hz and the vibration amplitude of 8 mm. From the vibrating screen 1 the mass by means of the belt conveyor 2 was supplied to the colloid mill 3 represented by the unit KDDJ-1,5 with the power capacity of 11 kW, with the rotation rate of 2,200 rot./minute of the rotor 20 that can also be equipped with a device for supplying drinking water from the block 4. In the colloid mill, the brewer's grains were humidified by means of water with the design amount of 170 litres (0.67:1) that was supplied to the colloid mill at the rate of 15 litres per minute. At the same time, the humidified brewer's grains were grinded in order to obtain a faction of 0.1-0.9 mm. The process of supplying the source raw materials and water to the loading tank 23 of the colloid mill 3 was controlled by means of three level-sensing devices 15, 16 and 17 built in the shell, of the loading tank 23 and a microcontroller located close to the level-sensing devices at the frame of the table on which the colloid mill is installed. At the same time, one of the level-sensing device, the upper one, 17 was used for controlling the maximum possible load of the raw material in the bunker (85-90% in volume of the maximum capacity of the bunker); when this level was reached a command to stop the loading conveyor was given; the second level-sensing device, the middle one, 16 was used for controlling the minimum level of the loaded raw material (25-30% in volume of the maximum capacity of the bunker); when this level was reached a command to start the loading conveyor and to supply the raw material was given what provided for continuous operation of the colloid mill. The third level-sensing device, the lower one, 15 was installed near the loading bunker's bottom at the distance of 15 cm from the bottom and it was used for controlling the minimum possible load of the raw material in the bunker (10-15% in volume of the maximum capacity of the bunker); if this level was not reached the colloid mill stopped until another portion of the raw material was supplied. After the colloid mill the produced pulp with viscosity of 900-1,200 cPa and the humidity level of 95% was delivered to the screw extractor 5 represented by the machine of KDLZ-1,5 model with the power capacity of 4 kW, with the rotation rate of 4.5-10 rot./minute. The output was suspension with the humidity level of 95% and viscosity of 2.013 cPa, and a waste product, barley's husk with the humidity level of 70.84%. By means of the impeller pump 6 with the power capacity of 0.25 kW with the rotation rate of 1,200 rot./minute the obtained suspension was delivered to the vibration filter 7 of XZS-1200-1S model with the power capacity of 0.75 kW with 0.3 mm openings. After filtration by means of the impeller pump 8 with the power capacity of 0.25 kW with the rotation rate of 1,200 rot./minute the food suspension was pumped to the collection tank 9. The husk naturally fell in the collection tank 10. Thus, suspension with the humidity level of 93%, with viscosity of 1.907 cPa and the particle size of 0.005-0.3 mm was produced. Then it was dried in the model spray-type drier HT-RY1500 during 8 hours at the temperature of 200° C. until humidity reached the level of 5% (capacity of this spray-type drier HT-RY1500 amounts to 1,500 ml of suspension per hour). 20.8 kg of barley protein concentrate was obtained. The concentrate (sample 1) is characterized by nutritional energy value of 255 kcal and the following composition, % wt (dry solid) (Table 1):
(13) TABLE-US-00001 TABLE 1 Brewer′s grains Food suspension, (original composition), % wt Composition % wt (sample 1) Protein 18.98 61.17 Fats 7.9 11.9 Fibre 13.6 5.7 Ash 2.2 6.8 at the same time protein from brewer′s gains is rich in the following amino acids: Arginine 1.07 4.5 Lysine 0.86 2.97 Tyrosine 0.61 2.75 Phenylalanine 1.23 4.0 Histidine 0.66 2.8 Isoleucine 0.79 4.1 Leucine 0.57 1.73 Methionine 0.5 1.95 Valine 1.06 3.5 Proline 2.05 5.17 Threonine 0.77 2.26 Serine 0.89 2.56 Alanine 0.94 2.95 Glycine 0.79 2.3 Cystine 0.46 1.97 Glutamic acid 4.57 12.32 Asparaginic acid 1.35 2.06 Total amount of amino acids 19.17 59.89 The total time for processing 260 kg of brewer′s grains amounted to 25 minutes.
Example 2. Production of Protein Barley Concentrate
(14) 200 kg of brewer's grains with the humidity level of 85.0% (original composition, energy value of 150 kcal) was processed and the suspension was obtained in the same way as in example 1. Thus, the suspension with the humidity level of 92%, with viscosity of 1.907 cPa and the particle size of 0.005-0.5 mm was produced. By means of a food centrifugal pump the suspension was supplied to the separating decanter LW220 at the rate of 100 liters per hour where it was processed until humidity reached the level of 60%. Then the pasty mass was dried in the model vacuum-type drier GRT-ZBG500 in the course of 8 hours at the temperature of 80° C. until humidity reached the level of 6.5% (the processing capacity of the vacuum-type drier amounts to 200 liters of water per a drying cycle that lasts 8-10 hours). Then the obtained dry product (0.1-5 mm granules) was subject to additional grinding in order to obtain particles with the diameter of 0.005-0.09 mm (disk mill VLM-80 with the grinding capacity of 80 kg/hour). 16.0 kg of barley protein concentrate was obtained. The concentrate (sample 2) is characterized by nutritional energy value of 245 kcal and the following composition, % wt (dry solid) (Table 2):
(15) TABLE-US-00002 TABLE 2 Brewer′s grains Food suspension, (original composition), % wt Composition % wt (sample 2) Protein 18.98 51.16 Fats 7.9 10.8 Fibre 13.6 5.7 Ash 2.2 6.56 at the same time protein from brewer′s gains is rich in the following amino acids: Arginine 1.07 4.27 Lysine 0.86 2.37 Tyrosine 0.61 2.55 Phenylalanine 1.23 3.57 Histidine 0.66 1.8 Isoleucine 0.79 1.7 Leucine 0.57 2.1 Methionine 0.5 1.5 Valine 1.06 2.62 Proline 2.05 4.21 Threonine 0.77 2.26 Serine 0.89 1.79 Alanine 0.94 3.6 Glycine 0.79 2.19 Cystine 0.46 1.91 Glutamic acid 4.57 8.63 Asparaginic acid 1.35 2.06 Total amount of amino 19.17 49.13 acids
The total time for processing 260 kg of brewer's grains amounted to 8 hours and 35 minutes (the processing was performed in a semi-industrial manner).
(16) Thus, barley protein product (concentrate) produced had a high protein content with preservation of the amino acid composition of brewer's grains and low content of fats and fibres. The time from loading raw material to obtaining the final product in the form of powder, for example when calculated for 100 kg of brewer's grains took between about 5 and 10 minutes with the equipment's capacity from 20 to 500 tonnes/day. At the same time, the amount of centrate being a waste product and subject to disposal was minimal and it was equal to max. 1% of the capacity of the brewer's grain processing line of kg/1 minute.
(17) Brewer's grains delivered from five different manufacturing facilities (sample) were processed by the described production line in accordance with the method of the present technology. The quantitative content of ingredients in the brewer's grains compositions was different from the original composition specified in table 1-2 within the limit of 1-5%. Table 3 shows compositions of barley protein concentrate with the optimal content of key components.
(18) TABLE-US-00003 TABLE 3 of barley protein concentrate Parameters sample 2 sample 3 sample 4 sample 5 sample 6 nutritional 245 kcal 260 kcal 258 kcal 255 kcal 265 kcal energy value (dry solid) humidity 6.5% 3.8% 5.7% 4.3% 6.2% particle size 0.01-0.1 0.01-0.09 0.005-0.04 0.005-0.03 0.005-0.01 mm mm mm mm Composition content (% wt) Protein 51.1 62.19 58.3 55.4 64.7 Fats 10.7 11.9 10.9 11.2 11.8 Fibre 5.4 4.8 5.2 3.7 5.8 Ash 6.4 5.82 6.3 4.7 6.7 Amino acid composition: Arginine 3.93 4.27 4.6 4.0 5.3 Lysine 1.95 3 2.72 2.87 3.17 Tyrosine 2.15 3.85 2.53 2.23 3.72 Phenylalanine 3.5 4.97 4.47 3.68 4.17 Histidine 2.1 2.9 2.1 1.85 2.1 Isoleucine/ 2.23 3.79 2.05 2.89 3.82 Leucine Methionine 2.43 2.55 2.1 1.97 2.1 Valine 2.84 2.62 2.9 2.75 3.16 Proline 3.85 4.73 4.1 3.95 5.1 Threonine 1.79 3.12 3.7 3.17 3.7 Serine 1.98 2.3 2.4 1.95 2.4 Alanine 2.84 4.1 4.3 3.97 4.3 Glycine 2.98 2.49 3.1 2.94 3.1 Cystine 2.62 2.1 2.4 1.95 2.4 Glutamic acid 7.7 9.8 8.5 7.94 10.3 Asparaginic acid 2.35 3.2 2.6 2.27 3.4 Total amount of 47.24 59.79 54.57 50.38 62.24 amino acids
(19) Table 4 includes parameters of processing brewer's grains (samples 3-7).
(20) TABLE-US-00004 TABLE 4 Processing parameters Equipment sample 3 sample 4 sample 5 sample 6 sample 7 Colloid mill/rotor 1,800 3,000 2,500 2,000 3,200 rotation rate (rot./second) Vibrating screen 10/10, 15 5/40, 10 7/30, 20 8/20, 15 6/50, 8 screen hole size (mm)/ vibration frequency (Hz and mm) Screw extractor/rotation 3 8 5 7 10 rate (rot./second) Filtration/hole size 0.6 0.3 0.4 0.5 0.2 (mm) Spray drying (time, — 8 hours 10 hours — 9 hours temperature) 200° C. 150° C. 180° C. Vacuum drying (time, 8 hours — — 10 hours — temperature) 80° C. 60° C.
(21) Based on the above-given data it can be concluded that barley protein concentrate with high protein content is produced despite the fact that various plants use different types of barley, have various technologies for manufacturing brewer's malt, various malt mix recipes for manufacturing beer, etc. The two-stage processing of brewer's grains (in the colloid mill and in the screw extractor) without using multi-step compression processes and thermochemical treatment enables to obtain a high-protein product with protein content of min. 50.0% wt (dry solid) and without gluten.
(22) This method enables to preserve all valuable biologically active components of the source brewer's grains. The rich chemical composition of brewer's grains with the minimal content of hydrocarbons predetermines its prospect in the food-processing industry, in particular its use as an albuminous vitamin-mineral additive in manufacturing of pastry products.