DE4231914A1 - Prepn. of protein-hydrolysates from animal and/or vegetable substrates - including a step of decomposing the substrate with an electrical discharge - Google Patents

Abstract

Prodn. of protein-hydrolysates from animal and/or vegetable substrates comprising: (a) comminution of the substrate; (b) heating the comminuted substrate; (c) mashing the substrate to a pumpable mass; (d) decomposing the substrate with an electrical discharge; and (e) sepn. of the aq. phase of the decomposed prod. from solid and water-immiscible residues. The entire process is carried out at a temp. below the protein coagulation temp., and step (c) is carried out using an aq. hydrolysate phase from the decomposed prod. USE/ADVANTAGE - The process is esp. useful for recovery of useful proteins from agricultural raw materials and abattoir by-prods. Components such as tissues and keratins, which are not used in the mashing process, can be used for prodn. of feeds and fertilisers. The process is easy and gives pure protein hydrolysates which are free of microorganisms. It is environmentally friendly in that it does not use acids, bases or other chemicals.

Description

The invention relates to a method for generating Protein hydrolyzates from animal and / or vegetabi len substrates, in which the substrates are first cut shrinks and then heated and into a pumpable Mass mashed, after which a digestion of the mashed substrate by means of electrical discharge gene and a separation of the aqueous product phase of Disclosure is made.

Slaughter by-products and raw materials of a vegetable nature from agriculture and industrial recycling agricultural products in and of themselves valuable raw products for the content they contain substances. One problem is the inexpensive and easy extraction of these ingredients. Especially animal offal, such as skins, hair, Bristles, feathers, bones, pieces of meat, blood, etc. largely draw a simple and inexpensive further processing what their ingredients concerns. The proteins contained therein is a valuable source of industrial raw materials that has so far been used insufficiently.

DE-A-37 13 179 is already a method for winning gelatin and products containing it known in the collagen-containing starting material in an aqueous medium with the help of electric current is unlocked. As a collagen-containing raw material Animal slaughter exits come into play sentence. The digestion is done with an electric  Discharge current with brief discharge pulses. A collagen-containing is obtained in the process Material that is used especially as glue.

The one used in this known method Discharge device is known per se and has been described for a number of purposes, including those given above.

Furthermore, DE-A-27 50 149 relates to a method for Production of keratin-like protein, in which keratin is hydrolyzed with saturated steam under pressure. The Bedin This procedure is quite drastic and at a high cost and a chemically modified pro dukt.

The aim of the invention is a method by which the in animal and vegetable raw materials, in particular Slaughter by-products and agricultural raw proteins contained in fabric products simply and widely can be separated purely.

This goal is achieved with a procedure of the beginning described type achieved at which the temperature wäh during the entire duration of the procedure under the Coagulation temperature of those contained in the substrate Proteins are kept and the mashing with from the Digestion of the aqueous hydrolyzate phase obtained men will.

The animal raw materials are skins, hair, bristles, Feathers, bones, horn components, meat components, blood and like slaughter by-products. When Vegetable substrates can be any protein-containing herbal products are used, in particular Agricultural and agricultural waste processing products.  

The substrates used are at the beginning crushed the method, for example with conventional Mills, crushers, wolves and the like. It should the smallest possible size reduction can be achieved because this facilitates the subsequent digestion of the substrates and promotes their pumpability. The sub strat, for example, with the help of liquid Nitrogen cooled and then mechanically ground the. The shredded substrates are next Step to a temperature below the coagulati on temperature of protein heated, preferably to a Temperature below about 70 ° C, which also during the whole procedure is maintained. This is done a separation of any fat components that may be present from the process by skimming, draining or Decanting can be removed.

Then the heated substrate becomes a pump capable mass mashed, why from the digestion obtained aqueous hydrolyzate phase is used. In the Start-up phase of the process if no hydrolyzate is available, can be mashed with water the. As soon as enough aqueous hydrolyzate is available stands, this is used for mashing.

Electrolytes can be added to the mashed substrate that increase the current conductivity of the mass. These electrolytes are said to be with the substrate and with the Products do not enter into chemical compounds and can be separated from the mixture using simple processes his. For example, this can be done in the aqueous phase soluble inorganic salts or organic compounds gene are used, for example table salt or Cinnamic acid. Adequate current conductivity is but also given without such additives.

The heated and mashed substrate becomes then by the action of electrical impulses in  unlocked a discharge route. Through the elec The cells are broken open and tric impulses protein contained therein released and into the aq phase. The proteins themselves are called Amphoteric substances can be polarized and become influenced the current pulses are hydrolytically split so that they - if necessary, only after several passes - in the individual Amino acids are split. This way it will be out the substrate used is essentially pure Pro tein detached while the remaining stock parts essentially in solid or suspended form stay behind.

Following the - preferably multiple - through this is unlocked by going through the discharge route sene substrate fed a separation path in which first the solid components are pressed and then the liquid phase, if necessary after filtration, is collected and drained. The drainage can for example by evaporating the aqueous phase (under reduced pressure) or freeze drying gene.

The slip of the mashed and possibly with a Electrolyte-offset substrate is preferably carried out in an electric pulse process in and of itself known discharge route. Here is about a Generator generates a high voltage. By means of high Power capacitors are discharges in the micro seconds range generated, for example 5 to 30 discharges dations per second that over the discharge route electrodes arranged in pairs on the substrate be given mixed. Have the discharges themselves a duration of microseconds. Technology becomes DE-C-12 37 541 and 19 46 267 and DE-A-16 67 029, 17 92 572, 29 07 887 and 31 16 623 pointed out as well to the information in DE-A-37 13 179.  

When digestion, protein is stored in the substrate and contained collagens from the cell structure dissolves, emerge from the cell and go into aqueous Solution about. The impulses of the discharge path controlled so that a burn or an inadmissible temperature increase does not occur. This is temperature monitoring is an advantage. In the case an inadmissible increase in temperature can Pulse number withdrawn or that the discharge route passing substrate to be cooled, for example instruct via a in the area of the discharge gap or downstream cooling or separate cooling section. The temperature of the mashed sub strats before entering the discharge route regulates that the tempera occurring during digestion door increase to a final temperature in the permissible Area leads.

The method according to the invention is preferred carried out continuously. It is getting raw imported and the raw material with already won NEN hydrolyzate made pumpable, possibly using electrical lyte are added. The electrolyte additive can completely be set if the mashing related Hydrolyzate has a sufficient electrical content has conductive products.

A vertical discharge path is preferably used arranged pipe related that on its inside which has electrodes arranged in pairs. The Electrodes are made of graphite, for example. The Substrate preferably passes through the discharge tube from bottom up, the flow rate is preferably 1 to 4 m / s.

To improve the outcrop to the free The mashed substrate can have multiple amino acids be guided through the discharge path, for example  wise up to four times, using a circular process can be set.

If a circulation process is used, preference is given to about 10 to 50% by weight, in particular about 25% by weight, of the treated substrate in circulation and through fresh mashed substrate replaced. The removed substrate is used for extraction the aqueous hydrolyzate phase treated with fresh substrate enriched recycle material again led through the discharge route.

The by pressing the solid residues and / or Fil aqueous hydrolyzate phase obtained is partly processed to a solid product, the other part in the Mash container returned to fresh substrate mash up. In the mashing container are preferred 10 to 50%, preferably about 25% fresh substrate with 50 to 90%, preferably about 75% aqueous hydro lysate phase mixed.

The hydrolyzate obtained is in and of itself converted into a powder or paste in a known manner, which, for example, as a basic material for chemical, related to pharmaceutical or food industries can be, but also as feed in the country economy.

The previously used processes for the extraction of Protein building blocks from animal or vegetable origin gear materials were all based on the use of Acids or enzymes and / or increased pressure and increased temperature. According to the method according to the invention is the removal of protein building blocks from the cell mass reached very gently with electricity. When using of acids and increased pressure / temperature conditions are changes in the protein building blocks or amino acids unavoidable, making a less pure product  is obtained. The use of enzymes is spoken of Chen expensive and not selective in every case. Erfin however, the release of the amino acids is in accordance with the invention achieved without an adverse chemical change. Aroma released together with the protein building blocks Teas, starches and sugar can in and of themselves known separation processes are separated, the amino acid mixture are separated in the usual way.

Those obtained in the process according to the invention Protein building blocks are, depending on the digestion and separation only available. The obtained according to the invention Hydrolyzate, in particular without the addition of foreign water (except in the start-up phase) a dry matter content of 15 to 40 wt .-% released amino acids. Known procedures based on the addition of extraneous water, achieve one Dry matter content from 3 to a maximum of 10%. The Product obtained according to the invention is after drying a free-flowing and essentially odorless sterile powder or paste.

Those not digested in the process according to the invention cell parts, keratins, tissue structures, lignin substances and residual materials can be removed / removed after pressing further processed into feed or fertilizer. Since acids, alkalis and chemical additives are not used Are used, pollutants fall into the process not on and the wastewater is limited to that the process coming hydrolyzate water that after the Separation of the products can be delivered without problems can.

In conventional digestion processes with acids below Pressure and at high temperatures occurs a very strong Odor development due to the breakdown of protein building blocks NEN who u. a. on the formation of mercaptans goes back. In contrast, in the method according to the invention  with comparatively low temperatures below very gentle conditions in the absence of chemicals worked. There is therefore no disintegration of the Protein building blocks and therefore no formation of gases. in the inventive method is the burden with Odorants, apart from the raw treatment fabrics, therefore extremely low.

The invention is described with reference to the accompanying fig dung explained in more detail using an embodiment each represents preferred method steps.

The animal or vegetable substrate is first fed to a comminution 1 , for example a conventional grinder, and then heated at 2 . The heated material is brought with a thick matter pump 3 into an intermediate vessel 4 with heating and agitator and homogenized there and heated to the process temperature. The material homogenized in this way is guided with a thick matter pump 5 into a separating device (decanter) 6 , in which fat and water are separated and fed by means of a pump 7 for further processing. Instead of a decanter, a double-shaft press can also be used. This step can be omitted for fat-free substances.

The material leaving the separating device 6 is conveyed via a screw 8 into the storage tank 9 with heating and agitator. Aqueous hydrolyzate phase passes into this tank 9 via the return line 11 for mashing the heated and degreased substrate.

From the storage tank 9 , the mashed substrate passes via the pump 10 into a metering container 12 for the pulse path, which has a heater and an agitator for metering auxiliary materials, for example the electrolyte. The mashed material is then fed from the metering container 12 with the aid of a metering pump 13 to the pulse path 16 with the discharge elements.

The digestion process initiated in the pulse section takes place continuously. Raw material is continuously supplied from the feed tank 9 via the metering container 12 . This raw material is mashed with hydrolyzate that has already been obtained and thus made pumpable and flowable.

The pulse path preferably consists of a vertically arranged tube that flows through from bottom to top. With the aid of the metering pump 13 and a metering pump 15 for circulating material, a flow rate of 1 to 4 m / s is ensured, the throughput being able to be monitored and controlled via a flow monitor 30 so that the required residence time and the temperature are maintained become.

In order to achieve full digestion under the most gentle conditions with regard to the applied current as a function of the number of pulses / second, the material flowing through the pulse path is circulated. It flows through the pulse path several times, preferably up to four times, depending on the requirements. About the mashing container 9 25% mashed raw material is fed in, 75% of the substrate treated in the impulse section is kept in circulation, 25% of the quantity in circulation is discharged.

The material emerging from the pulse path 16 reaches into a line 17 which forks and one hand leads into a circulation tank 14 with stirrer and heating or cooling and on the other hand via a discharge line and pump 18 in an intermediate container 19th About the discharge pump 18 10 to 50% of the digested substrate and in particular in particular about 25% are preferably removed from the circulation.

The material in the circulation container 14 is guided via a metering pump 15 in the circuit back into the impulse section 16 . The amount circulated itself is determined from the material fed by metering pumps 13 and 15 in coordination with the flow switch 30 and a control. 75% circulating material and 25% mixed mashed substrate are particularly preferred.

The material discharged from the process via the discharge pump 18 in the intermediate container 19 passes through a pump 20 into the separation system, in which the dissolved and undissolved are separated from one another. The separation system preferably consists of a decanter 21 , a twin-shaft press 22 and a precoat filter 23 , from each of which solids are discharged at 26 and aqueous hydrolyzate reaches the hydrolyzate container 24 via line 27 . The hydrolyzate container 24 is connected via a pump 25 and the return line 11 to the storage tank 9 , in which heated and fat-depleted substrate is mashed with the hydrolyzate for pumpability. Hydrolyzate which is not returned to the receiver tank is sent for storage or further processing, for example fine filtration or amino acid separation.

The separation of the digested substrate takes place - after the intermediate storage in the tank 19 - essentially union with the help of the decanter 21 , the double screw press 22 and the subsequent pressure filtration 23 , with filter aids (agglomerates) being added. The hydrolyzate obtained in this way is completely sterile and can be processed further using known methods and in particular processed for the individual amino acids. The hydrolyzate itself is absolutely sterile and, after decanting, pressing and filtering, contains almost exclusively the respective amino acids.

The high voltage for the pulse path 16 is generated with the aid of a generator 28 . The current is applied to the discharge path via a chopper and high-performance capacitors in micro bursts. Control and control take place via an oscillograph 29 for the current strength and the number of pulses / time unit. The current is a discontinuous direct current. It can be a pulse current or a discharge current, the latter being generated via capacitors. Capacitors with a capacitance of 5 to 25 µF and a pulse frequency of 5 to 30 pulses / s have proven to be particularly cheap. It is preferably operated with high voltage in a range from 2 to 20 kV. The field strength is dependent on the diameter of the impulse section and quantity-dependent, it can be up to 100 kV in systems with an hourly output of 8 to 10 t. Voltage, pulse sequence and pulse duration are varied in dependence on the material used so that the protein constituents of the substrate are broken down as completely as possible into the individual amino acids.

The hydrolyzate obtained is at a working temperature Free from microorganisms below 70 ° C. At her conventional procedure this became sterility and this Work result only by working with time, pressure or Acids reached.

The amino acids in the hydrolyzate are free separable and do not go through the process mentioned they are still bound by heat, pressure or acid ren unstable. Loss of quantity of the individual protein building stones are excluded by the new process.

Claims (13)

1. Process for the production of protein hydrolyzates from animal and / or vegetable substrates by comminuting the substrates, heating the comminuted substrate, mashing the heated substrate to a pumpable mass, disintegrating the mashed substrate by means of electrical discharges and separating the aqueous phase of the In conclusion of solid and water-immiscible liquid residues, characterized in that the temperature is kept below the coagulation temperature of protein during the entire process and the mashing is carried out with the aqueous hydrolyzate phase obtained from the digestion. 2. The method according to claim 1, characterized in that that the process temperature is kept below 70 ° C becomes. 3. The method according to claim 1 or 2, characterized characterized that the animal or vegetable First crushed substrate and then under Separation of liquefied fat components heated becomes. 4. The method according to any one of the preceding claims characterized in that the mashed substrate is unlocked in the electro pulse method.   5. The method according to claim 4, characterized by Discharges in the microsecond range from 5 to 30 Discharges / s. 6. The method according to any one of the preceding claims, characterized in that the mashed sub strat from bottom to top by a vertical angle arranged tube with internally arranged electrodes as Discharge route is performed. 7. The method according to any one of the preceding claims, characterized in that the discharge path is accompanied by a cooling section. 8. The method according to any one of the preceding claims, characterized in that the mashed sub strat at 1 to 4 m / s through the discharge path to be led. 9. The method according to any one of the preceding claims, characterized in that in the mashing container 10 to 50, preferably about 25% substrate and 50 to 90, preferably about 75% aqueous hydrolyzate phase be mixed together. 10. The method according to any one of the preceding claims, characterized in that the slip is in circulation process takes place and the substrate the discharge stretch several times, preferably up to four times, goes through. 11. The method according to claim 10, characterized in that 10 to 50%, preferably about 25% of the in the up final circulating open substrate be removed. 12. The method according to any one of the preceding claims, characterized in that the aqueous hydrolyzate  phase by pressing off the solid residues and / or Filtration is separated. 13. The method according to any one of the preceding claims, characterized in that the protein hydrolyzate in in a manner known per se, further cleaning and subjected to separation steps.