Process and apparatus for performing cell lysis

Abstract

1. A process for performing lysis of cells of plant material or a portion thereof, the process incorporating the steps of obtaining the plant material at a target particle size; combining the plant material in a fluid medium; exposing the plant material to a series of predetermined processing conditions; degassing the plant material, thereby substantially removing gas; and introducing the plant material into a two-stage compression device, in which the plant material is subjected to a first pressure in a first stage of high fluid pressure compression, followed by a second pressure in a second stage of rapid decompression, where the first pressure is substantially higher than the second pressure, thereby subjecting the plant material to cavitation of water within the cell walls, causing the cell walls to rupture.

Description

[Technical Field]

[0001] The present invention relates to the field of plant cell lysis technology. In particular, the present invention relates to improved processes and apparatus for carrying out plant cell lysis for the extraction of functional and nutritional compounds from plant-derived materials. [Background technology]

[0002] For example, plant materials, including grains, legumes, vegetables, grasses, fibers, and nuts, have long been recognized as rich sources of functional and nutritional compounds. These compounds, including proteins, carbohydrates, lipids, vitamins, and minerals, contribute to the nutritional value of the plant material and may also have beneficial effects on human health. However, these compounds are often located inside the cells of the plant material and are therefore not easily accessible.

[0003] Various processes have been developed to break the cell walls of plant materials and release functional and nutritional compounds. These processes typically involve physical disruption of the cells, such as cutting, grinding, soaking, heating, or mashing. While these processes can effectively break the cell walls and release the compounds, they can also cause damage to the compounds, reducing their functionality and nutritional value. For example, heating can denature proteins and destroy vitamins, while excessive shearing can cause physical damage to the compounds.

[0004] Another challenge in processing plant material is the presence of entrained gases in the plant material slurry. These gases can cause problems in downstream processing steps, such as foaming of the slurry and damage to processing equipment. Therefore, it is often desirable to remove or reduce the entrained gases before further processing. This is typically achieved by degassing, which involves subjecting the slurry to reduced pressure to allow the gases to escape.

[0005] High-pressure homogenization is a technique that has been used to disrupt cells and release functional and nutritional compounds (as well as create more stable emulsions). In this process, a plant material slurry is subjected to high pressure, which causes the cells to burst and release the compounds. However, conventional high-pressure homogenization processes typically involve a single stage of compression, and the pressure is not sufficient to effectively (and uniformly) rupture the cells without causing damage to the compounds and / or the equipment.

[0006] Therefore, there is a continuing interest in developing improved processes for extracting functional and nutritional compounds from plant material. These processes would ideally allow for effective cell lysis without causing substantial damage to the compounds and / or equipment, and would also effectively remove or reduce entrained gases in the plant material slurry. Summary of the Invention

[0007] According to a first aspect of the present invention, there is provided a process for performing lysis of cells of plant material or parts thereof, the process comprising obtaining the plant material at a target particle size; combining the plant material in a fluid medium; optionally incorporating other desired chemicals or agents in a container; exposing the plant material to a series of predetermined treatment conditions; degassing the plant material to thereby substantially reduce or remove entrained gases; and introducing the plant material into a two-stage compression device in which the plant material is subjected to a first pressure in a first stage of high fluid pressure compression, followed by a second pressure in a second stage of rapid decompression, where the first pressure is substantially higher than the second pressure, thereby exposing the plant material to cavitation of water inside the cell walls and causing rupture of the cell walls.

[0008] The target particle size of the plant material may be in the range of 400 to 2000 microns, more preferably 400 to 800 microns. Known techniques for preliminary reduction of the particle size of the plant material may be used, for example, milling, grinding, cutting, micronizing, etc.

[0009] The set of predetermined processing conditions may depend (or may be optimized) on the raw materials used and may include one or more of temperature, temperature profile, pH, viscosity, and time. The set of predetermined processing conditions may include temperatures below 60°C for certain plant materials that are susceptible to flavor and / or nutritional deterioration. However, it should be understood that this is not a physical or technical limitation of the process.

[0010] The degassing and compression processes can occur simultaneously via partial recirculation of the compressed material from the outlet of the degassing device back into the container. In an exemplary embodiment, the compression device comprises one or more pistons within a cylinder through which the fluid passes. In further exemplary embodiments, the compression device comprises three, five, seven, or nine pistons within a cylinder through which the fluid passes.

[0011] The inventors have also found that a degassing step carried out prior to the compression step effectively removes entrained gas from the slurry of plant material, which is particularly advantageous as it allows for higher pressures to be achieved within the two-stage compression device and more consistent cell disruption (i.e., cell lysis or cavitation) during the compression stage, as well as preventing other problems such as auto-oxidation of any fatty acids present.

[0012] The inventors have found that the pressure shock to the cell walls provided by the sudden drop in pressure (i.e., rapid decompression) from the first stage to the second stage of a two-stage compression device effectively ruptures (i.e., lyses) the cells without causing denaturation or other damage to the compounds within the cells, thus making them more functional and bioavailable compared to other processes for the destruction or disintegration of plant cells.

[0013] Without wishing to be bound by any particular theory of operation, the inventors hypothesize that the initial higher fluid pressure phase of compression causes an increase in fluid pressure outside the cell, thereby tending to force the surrounding fluid into the cell. The sudden and rapid drop in pressure (due to rapid decompression) outside the (thus enlarged) cell causes the fluid inside the cell to expand due to the large pressure gradient across the cell wall, tending to rupture the cell wall to equalize the fluid pressure.

[0014] The first pressure may be between 400 bar and 3000 bar, more preferably between 900 bar and 2000 bar. At 900 bar and above, sterilization of the plant material may be carried out at relatively low temperatures (e.g., below 60°C) compared to other forms of cell lysis, further enhancing preservation of nutritional and functional compounds released from the cells.

[0015] The second pressure may be between atmospheric pressure and 400 bar.

[0016] To provide a pressure drop sufficient to effect cell lysis via cavitation, the ratio of the first pressure to the second pressure can be 4:1 or greater. For example, the first pressure is approximately 900 bar and the second pressure is approximately 200 bar. However, to achieve efficient cell lysis, it is preferred that the first pressure be at least 400 bar or greater.

[0017] In other useful embodiments, the first pressure is in the range of approximately 600 to 1500 bar and the second pressure is in the range of approximately 0 to 350 bar.

[0018] The degassing device may comprise a substantially vertical pressure vessel having an outer tube and an open inner annular tube, the inner tube extending from an inlet end of the degassing device for 65% to 75% of the length of the outer tube, and plant material entering the degassing device being directed toward the interior of the inner tube.

[0019] According to another aspect of the present invention there is provided a two-stage high fluid pressure compression device for performing lysis of cells of plant material, the device comprising a first stage for exposing the plant material to a first pressure and a second stage for exposing the plant material to a second pressure substantially lower than the first pressure, wherein the pressure difference between the first and second stages causes cavitation of water inside the cell walls of the plant material, leading to rupture of the cell walls.

[0020] The first pressure may be between 400 bar and 3000 bar, more preferably between 900 bar and 2000 bar. At 900 bar and above, sterilization of the plant material may be carried out at relatively low temperatures (e.g., below 60°C) compared to other forms of cell lysis, further enhancing preservation of nutritional and functional compounds released from the cells.

[0021] The second pressure may be between atmospheric pressure and 400 bar.

[0022] To provide a pressure drop sufficient to effect cell lysis via cavitation, the ratio of the first pressure to the second pressure can be 4:1 or greater. For example, the first pressure is approximately 900 bar and the second pressure is approximately 200 bar. However, to achieve efficient cell lysis, it is preferred that the first pressure be at least 400 bar or greater.

[0023] In other useful embodiments, the first pressure is in the range of approximately 600 to 1500 bar and the second pressure is in the range of approximately 0 to 350 bar.

[0024] The two-stage high fluid pressure compression device may be coupled at its inlet to a degassing device comprising a substantially vertical pressure vessel having an outer tube and an open inner annular tube, the inner tube extending from the inlet end of the degassing device for 65% to 75% of the length of the outer tube, and plant material entering the degassing device being directed toward the interior of the inner tube.

[0025] According to another aspect of the present invention there is provided the use of a two-stage high fluid pressure compression operation to cause lysis of cell walls of plant material entrained in a fluid medium through cavitation of water inside the cells, the first of the two stages being carried out at a (first) pressure substantially higher than the (second) pressure of the second stage, whereby the plant material is exposed to cavitation of water inside the cell walls, causing rupture of the cell walls.

[0026] Preferably, the compaction is carried out via a device comprising one or more pistons in a cylinder through which a fluid passes. Preferably, the compaction operation is carried out subsequent to or simultaneously with degassing of the plant material.

[0027] According to another aspect of the present invention, there is provided a two-stage high pressure compression device adapted to cause lysis of cell walls of plant material entrained in a degassed fluid slurry, wherein as the plant material passes therethrough, the first of the two stages is carried out at a (first) pressure substantially higher than the (second) pressure of the second stage, thereby exposing the plant material to cavitation of water inside the cell walls and causing rupture of the cell walls.

[0028] Preferably, the compression device is coupled at its inlet to a degassing device comprising a pressure vessel having an outer tube and an open inner annular tube, the inner tube extending from the inlet end of the device for 65% to 75% of the length of the outer tube, and the plant material entering the device is directed toward the interior of the inner tube.

[0029] According to another aspect of the present invention, there is provided nutritional compounds obtained from plant material via the above process.

[0030] According to another aspect of the present invention, there is provided a food product comprising plant material processed by a method comprising obtaining the plant material at a target particle size; combining the plant material in a fluid medium in a container; exposing the plant material to a series of predetermined processing conditions; degassing the plant material (and / or plant material slurry) to substantially reduce or remove entrained gases; and introducing the plant material into a two-stage compression device in which the plant material is subjected to a first pressure in a first stage of high fluid pressure compression, followed by a second pressure in a second stage of rapid decompression, where the first pressure is substantially greater than the second pressure, thereby exposing the plant material to cavitation of water within cell walls and causing the cell walls to rupture.

[0031] The target particle size of the plant material may be in the range of 400 to 2000 microns, more preferably 400 to 800 microns. Known techniques for preliminary reduction of the particle size of the plant material may be used, for example, milling, grinding, cutting, micronizing, etc.

[0032] The first pressure may be between 400 bar and 2000 bar, and the second pressure may be between atmospheric pressure and 400 bar.

[0033] According to another aspect of the present invention, there is provided a food product incorporating the lysed plant material obtained by the above process.

[0034] Preferred embodiments of the invention will now be described, by way of specific, non-limiting examples, with reference to the drawings, in which: [Brief explanation of the drawings]

[0035] [Figure 1] 1 is a flow chart illustrating a preferred embodiment of a process according to the present invention.

[0036] [Figure 2] 1 is a schematic top view of a plant for carrying out the process according to the invention; FIG.

[0037] [Figure 3] 1 is a photograph of a hammer mill suitable for the size reduction step of the present invention.

[0038] [Figure 4] 1 is a schematic top view of a plant for carrying out the process according to the invention; FIG.

[0039] [Figure 5] 1 is a photograph of a bioreactor suitable for use in the present invention.

[0040] [Figure 6] 1 is a schematic top view of a plant for carrying out the process according to the invention; FIG.

[0041] [Figure 7] 1 is a photograph of a typical plate heat exchanger of the type used in the process of the present invention.

[0042] [Figure 8] 1 is a schematic top view of a plant for carrying out the process according to the invention; FIG.

[0043] [Figure 9] 1 illustrates a degassing tube for use in the present invention.

[0044] [Figure 10] 1 is a schematic top view of a plant for carrying out the process according to the invention; FIG.

[0045] [Figure 11] 1 is a cross-sectional schematic view of a two-stage homogenizer head according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0046] The following description describes exemplary aspects of the present disclosure. However, it should be recognized that such description is not intended as a limitation on the scope of the present disclosure. Rather, the description also encompasses combinations and modifications to those exemplary aspects described herein.

[0047] The processes and apparatus described herein may offer several advantages. For example, the process may enable the extraction of functional and nutritional compounds from plant material in a manner that does not substantially reduce their nutritional value or functionality. This is achieved by avoiding the denaturation of compounds at higher temperatures or structural damage due to excessive shear, which are common problems associated with conventional plant material processing methods. Furthermore, the process may be particularly beneficial for the production of plant-based milks or concentrates, reducing or eliminating the need for additional functional additives to provide a fully functional product compared to dairy products.

[0048] The present disclosure relates to a process and apparatus for performing lysis of cells in plant material. In particular, the present disclosure may provide a method for obtaining functional and nutritional compounds from plant-derived materials, such as grains, legumes, fruits, vegetables, grasses, fibers, and nuts. The process may involve obtaining the plant material at a target particle size, combining the plant material in a fluid medium, optionally incorporating other desired chemicals or agents, and exposing the plant material to a series of predetermined treatment conditions. The plant material is then degassed to substantially reduce or remove entrained gases and subsequently introduced into a two-stage compression device, in which the plant material is subjected to a first pressure in a first stage of high-fluid pressure compression, followed by a second pressure in a second stage of rapid decompression, where the first pressure is substantially higher than the second pressure. The process (and particularly the rapid and explosive decompression) preferably results in cavitation of the water inside the cell walls, causing the cell walls to rupture and the desired compounds to be released.

[0049] In one embodiment, the present invention is a process for achieving rupture or lysis of edible plant cell material at relatively low temperatures (e.g., below 60°C), thereby releasing relatively undegraded functional and / or nutritional compounds compared to known prior art processes. In an alternative embodiment, the present invention is a process and apparatus for achieving high throughput of lysed plant material having an average particle size of 1 to 40 microns. For example, the above process and apparatus are capable of producing in excess of 1,000 L / hour of lysed plant material (in a slurry solution), optimally 2,000 to 10,000 L / hour of lysed plant material, depending on the plant material input rate used.

[0050] The key to this process is subjecting the plant cells (prepared as a wet slurry) to a two-stage compression process in which the first stage operates at a relatively high pressure, immediately followed by a second, lower compression stage operating at a relatively low pressure. The immediate pressure drop (i.e., rapid or explosive decompression) ruptures the cell walls, releasing various compounds from within the cells, which then become relatively more functional and / or bioavailable for use as or in food ingredients, compared to processes that cause greater levels of damage to these compounds through the generation of higher temperatures that often tend to denature these compounds.

[0051] Typically, the first pressure is between 400 bar and 3000 bar, more preferably between 900 bar and 2000 bar. At 900 bar and above, sterilization of plant material can be carried out at relatively low temperatures (e.g., below 60°C) compared to other forms of cell lysis, further enhancing preservation of nutritional and functional compounds released from the cells. Typically, the second pressure is between atmospheric pressure and 400 bar.

[0052] Typically, the ratio of the first pressure to the second pressure is 4:1 or greater to provide a sufficient pressure drop to effect cell lysis via cavitation. For example, without limiting the scope of the present invention, the first pressure may be approximately 900 bar and the second pressure may be approximately 200 bar. However, the particular pressure will depend on one or more of the desired particle size of the product plant material slurry, the desired throughput of the equipment and process, the required level of sterilization of the product plant material slurry, the required degree of complete lysis of cells in the plant material, and the desired degree of homogenization of the product plant material slurry.

[0053] In other useful embodiments, the first pressure is in the range of approximately 600 to 1500 bar and the second pressure is in the range of approximately 0 to 350 bar.

[0054] It is particularly advantageous if the process provides a step prior to the two-stage compression device in which the plant material slurry is substantially degassed to prevent excessive foaming or other deleterious processes from occurring within the product plant material slurry. Additionally, given the significant pressures used in the two-stage compression device, degassing is highly desirable to prevent damage to the hydraulic equipment used to create this significant pressure (especially over extended periods of use). By removing entrained gas from the plant material slurry, the two-stage compression device is less likely to encounter air pockets within the plant material slurry, which can often cause damage to the equipment (in the case of hydraulic systems with piston assemblies).

[0055] The present invention also encompasses the above-described two-stage compression operation itself, characterized by the above-described substantial pressure drop and a compression device adapted to perform this operation.

[0056] For a typical plant material processed through the process of the present invention, the major steps involved are typically as follows (although it should be understood that depending on the particular plant material being processed, one or more of these steps may not be necessary):

[0057] Size reduction > aqueous soaking > temperature adjustment > degassing > high pressure compression > post processing / packaging.

[0058] As noted above, certain applications (especially those in which "soft" plant material is being processed) do not require an aqueous steeping step. This is because it is typically more suitable to use a liquid to soften the plant material prior to milling or size reduction, as with grains and pulses. Similarly, many plant materials do not require temperature conditioning. High temperatures are typically only used when enzymes or other processing aids (which require high temperatures) are used.

[0059] Referring to Figure 1, a typical overall process flow of the process according to the invention is shown. Figures 2 to 11 show sample layouts of schemes in which the process according to the invention can be implemented, which are referred to below in the examples that describe the process of the invention in more detail.

[0060] Reduction of raw material size Feedstock size reduction is the first processing step in the process of the present invention. The described process of the present invention works optimally with a slurry feedstock of finely ground solid plant material having a particle size of 1.0 mm (1000 microns) or less, preferably less than 0.8 mm (800 microns). However, it should be understood that for certain "softer" ingredients, it may be possible to use a slurry feedstock having plant material with a particle size of up to 2000 microns or even 3000 microns.

[0061] Depending on the nature of the plant material being processed, an appropriate pre-processing device (either wet or dry processing) can be selected to achieve the desired particle size, for example, a grinder, colloid mill, pulverizer, or hammer mill for dry grains, or a bowl chopper for wet products to create a puree. Alternatively, the raw material can be fed to the processing plant at the appropriate fineness.

[0062] Too large a particle size results in a low specific surface area (surface area per unit mass) of the material. Consequently, the reaction yield in the downstream bioreactor and the functionality of the slurry are also reduced. Large particle sizes also tend to cause caking or blocking in downstream plate heat exchangers, leading to production interruptions and loss of performance and process control. Larger particles can also have a detrimental effect on compression devices, potentially leading to rapid wear of internal components or blockage of openings in the manifold, which can affect product quality or prevent the plant material slurry from entering the two-stage compression device.

[0063] FIG. 2 shows the two-stage compression device 15 (labeled High Pressure Homogenizer), and hammer mill 5, and the relative location of the process 10 with respect to the grinding operation, and FIG. 3 shows a typical hammer mill 5 with an input chute 20 that may be used.

[0064] Soaking / Steeping of raw materials In this example, steeping of the ground raw material is accomplished in a 1,000 L tank (either a bioreactor or steep tank 25, depending on the particular plant material being processed). The bioreactor or steep tank 25 is used to steep the ground plant material in water and, if necessary, perform other operations to prepare the material for the compaction operation, including, but not limited to, heating, cooling, enzyme treatment, and pH adjustment. This is typically done to prepare a slurry for further processing and to achieve preliminary functions. The locations where this operation occurs in the plant of this example are circled and in bold in Figure 4.

[0065] Depending on the raw material and the desired product function, steeping may involve simply dispersing the raw material in cold water without any specific further action (e.g., when processing used coffee grounds, fruits, vegetables, chili peppers, garlic, fig leaves, etc.).

[0066] The steeping operation in this example is managed in batch mode, with different ingredients being precisely metered and added as needed according to the recipe in use. The bioreactor tank (or steeping tank 25 if no enzyme treatment is required) is equipped with an agitator to obtain a homogeneous distribution of material and temperature throughout the slurry. Advantageously, a manhole in the top of the bioreactor tank or steeping tank 25 allows for the addition of any desired different ingredients at different stages of the steeping process.

[0067] The high shear mixer can be set up in a recirculation mode to ensure that particle size is further standardized. Another particle size standardization feature, such as a strainer to retain any particles above a critical size, can be fitted after the bioreactor.

[0068] FIG. 5 shows a typical stainless steel bioreactor tank 30 (or immersion tank if enzyme treatment is not required) according to this embodiment.

[0069] Heat Exchange System Figure 6 shows the major components 35 of the heat exchange system and their location relative to the bioreactor (or submersion tank 25). The bold circled areas indicate where in the overall process this activity occurs. Typically, the heat exchange process is a service step that can be used in conjunction with the submersion step described above.

[0070] In this example, there are six components that make up the heat exchange process. The core device is the Plate Heat Exchanger. This is where the plant material slurry and the technical fluid (either hot or cold water) come into thermal contact for the purpose of transferring heat to and from the slurry. A glycol chiller is used as a cooling unit to cool the cold water / glycol buffer tanks when cooling is required in the heat exchanger. A hot water buffer tank provides heating liquid as needed by the heat exchanger. Each buffer tank is fitted with its own centrifugal pump to circulate the fluid through the heat exchanger.

[0071] If desired, a chilled water circuit can also be used to supply the compression device. This is not a critical requirement, but simply an optional optimization to avoid losing water to the compression device (default supply).

[0072] FIG. 7 shows a typical plate heat exchanger 40 of the type used in this embodiment.

[0073] Degassing Degassing is a highly preferred step before sending the slurry to the compression device. In this example, it occurs in a custom-built pressure vessel device. The bolded and circled text in FIG. 8 illustrates where this degassing operation 45 occurs throughout the process. As explained in detail above, given the significant pressures used in the two-stage compression device, a degassing step is highly desirable to prevent damage to the hydraulic equipment used to create this significant pressure (especially over extended periods of use). By removing entrained gas from the plant material slurry, the two-stage compression device is less likely to encounter air pockets within the plant material slurry, which can often cause damage to the equipment (in the case of hydraulic systems with piston assemblies).

[0074] The deaerator is a tubular pressure vessel in this embodiment (as shown in FIG. 9a) having an outer tube 50 and an open inner annular tube 55 that extends from the inlet end 60 of the device for 65% to 75% of the length of the outer tube 50, with plant material entering the device being directed into the interior of the inner tube 55, per FIGS. 9a and 9b. As shown in the figures, the tubular pressure vessel (including the outer tube 50 and open inner annular tube 55) is substantially vertical to maximize the action of gravity, so that as the plant material slurry flows through the open inner annular tube 55 via the inlet 60 and overflows into the cavity 75 between the outer tube 50 and the inner tube 55, any entrained gases in the plant material slurry are vented to the top of the outer tube 50 and (optionally) vented from the deaerating device via the outlet 70.

[0075] Once the slurry has been properly prepared and processed in the bioreactor (or immersion tank 25), an eccentric screw pump transfers the slurry through the degassing device via the open inner annular tube 55, with the internal pressure in the degassing device at a maximum of 9 bar. The degassing device is equipped with two pressure relief gauges, one at the top (recirculation outlet 70) which is connected to the recirculation line of the bioreactor or immersion tank 25, and one at the bottom (outlet 65) which is connected to the two-stage compression device inlet.

[0076] Operation entails opening the outlet gauge 65 and then slowly closing the recirculation outlet 70 to create the appropriate equilibrium and backpressure, approximately 2-6 bar, against the partially closed inlet valve for a given pump pressure. This creates a constant inverted wedge in the slurry flow, releasing entrained bubbles, foam, and trapped air in the slurry due to agitation and heat exchanger recirculation within the bioreactor. This is important for achieving higher pressures, above 900 bar, in the compression stage and producing consistent, uniform cell disruption (i.e., cell lysis) in two-stage compression devices (i.e., high-pressure homogenizers).

[0077] For example, removing air from the slurry helps to avoid oxidation of the slurry, preventing "stale" flavor notes and other undesirable reactions. Degassing also facilitates downstream packaging by minimizing foaming of the compressed product. Also, if the slurry is not degassed, the compression device may be damaged and worn due to the very high pressures generated in the dissolution process. It also ensures a constant back pressure on the compression device.

[0078] FIG. 9a illustrates a degassing tube according to this embodiment, and FIG. 9b illustrates the operation of the degassing system.

[0079] In Figure 9a, the deaerator consists of an outer tube 50 that is pressure sealed at each end. There is an inner tube 55 that extends approximately 65% ​​of the length of the outer tube 50 from the inlet 60 end. However, it should be understood that in alternative embodiments, the inner tube 55 may extend approximately 50% to 90% of the length of the outer tube 50 from the inlet 60. A slurry inlet 60 is located at the bottom of the deaerator and is positioned so that the slurry enters through the bottom of the inner tube 55. There are two outlets, one to a two-stage compression device 65 and one to a recirculation circuit returning to the bioreactor or dip tank 25. The outlet 65 to the two stage compression device is also located at the bottom of the degassing device and is connected to the annular space 75 between the inner tube 55 and the outer tube 50, while the recirculation outlet 70 is at the top of the degassing device and is fitted with a gas pressure relief valve and a pressure gauge 80 to ensure that a safe pressure within the degassing device is maintained below 9 bar, preferably between 2 and 6 bar.

[0080] Figure 9b illustrates the deaerator's operating principle. Slurry is pumped from the reactor or dip tank 25 to the inlet 60. The slurry rises through the inner tube 55 and fills the deaerator. In recirculation mode, as shown on the left, the outlet 65 to the two-stage compression device is closed and the recirculation outlet 70 is opened.

[0081] In compressor operating mode, the recirculation outlet is partially open and the compressor outlet is fully open. The slurry flows up the inner tube and down the side, filling the bottom of the annular space and discharging into the compressor. The headspace above the inner tube accumulates entrained gas from the slurry and is vented to operate at a back pressure of 2 to 6 bar, allowing liquid to continue flowing into the compressor and entrained gas to be vented to the atmosphere.

[0082] High-pressure compression - "cell rupture" FIG. 10 illustrates where an embodiment of a two-stage high pressure compression device 85 may be located within a plant.

[0083] Cell disruption (or lysis via cavitation) is the final and critical step in the process according to the present invention. This occurs within a compression device 85. In this example, the compression device is a modified Ultra High Pressure Homogenizer (HPH). Such HPHs are commonly used to homogenize immiscible liquids into emulsions and operate like a positive displacement pump with a valve. An internal piston forces fluid at high pressure through a small orifice. This increases velocity and reduces pressure, causing turbulence / pressure differentials, disrupting and dispersing particles.

[0084] An example of a type of HPH known in the art is the SPX FLOW APV Gaulin & Rannie Homogeniser supplied by SPX Flow Technology (Delavan, WI USA), which was modified for use in this example.

[0085] As used in this example of the process of the present invention, the modified HPH85 operates on a similar principle to a regular HPH, but with a two-stage operation, as illustrated in Figure 11. In Figure 11, it can be seen that there are two successive compression chambers, with the first chamber operating at a higher pressure (typically 400-3000 bar). The slurry proceeds directly from the high-pressure chamber to the second chamber, which operates at a lower pressure (typically atmospheric pressure to 200 bar). The sudden pressure drop between the first and second chambers creates a pressure shock on the cell walls of the material in the slurry. Water molecules forced into the cells at the higher pressure rapidly expand at the lower pressure, rupturing the cell walls via cavitation and thereby lysing the cells. This releases functional and nutritional compounds without thermal damage (operation can be performed below 70°C, more typically below 60°C).

[0086] At pressure drops from 900 bar to lower pressures, especially 0-100 bar, this pressure swing cavitation effect causes most biological cells to burst, meaning that organisms (such as bacteria and even spores) are destroyed (causing a sterilizing effect) and plant organisms release intracellular material such as, but not limited to, proteins, cellulose, and aromatic alcohols.

[0087] From here, the ruptured cells and released material are sent for further processing or packaging depending on their intended use.

[0088] The inventors have carried out experiments on a variety of plant and animal cell-based materials using the process according to the present invention, and the results are shown in Table 1 below. For each product processed, the milled slurry viscosity, pre-measured viscosity, post-treatment slurry viscosity, and dilution factor are given according to known observations / published information. [Table 1] JPEG2026506389000003.jpg184169

[0089] For the above experiments, prior to cell disruption, analyses were performed to establish viscosity specifications and fineness of grind for various feed materials. After cell disruption, the microscopic range of cell disruption and stability under cooling and centrifugation were tested. Moisture variation was determined by the required viscosity that allowed for efficient screw pumping and degassing. This ranged from 22% to 66% solids.

[0090] All samples were examined microscopically for residual fibers and it was determined that complete cell lysis had been achieved when no fine fibers were visible at 400x magnification.

[0091] The following process conditions were applied:

[0092] Bowl chopper, meat grinder mixer size reduction parameters: all <0.8mm

[0093] Hammer mill, colloid mill, sugar mill, roller mill: all <0.8mm

[0094] Immersion tank concentration of material, viscosity less than 20,000 centipoise (1:3 to 1:5 dilution). Residence time 1 to 3 hours.

[0095] Target temperature for pre-homogenization: below 16°C. Processing temperature can vary from 60°C to 85°C.

[0096] The compressed pH was neutral or naturally acidic. If debittering was required, the processing pH may need to be adjusted to 3.5-8 and then returned to a neutral pH of 7.0. Therefore, protein protection is essential, so potassium hexa-metaphosphate is used to neutralize the pH, if necessary.

[0097] Degassing pressure: 2 bar to 9 bar, preferably carried out at 6 bar.

[0098] Raw slurry inlet pressure setting: 9 bar pressure.

[0099] Eccentric screw pump flow rate: approximately 600 l / h, maximum 1500 l / h.

[0100] Target outlet pressure is approximately 600 bar.

[0101] Compression: 1st stage pressure setting of 900-1500 bar, 2nd stage pressure of 0-350 bar.

[0102] Homogenizer source: Gaulin and Rannie homogenizer (twin head customized according to the above invention) manufactured by APV Group.

[0103] Example 1 - Oat Concentrate An oat milk concentrate product was made using a process and compression system according to the present invention.

[0104] The compositions are shown in Table 2 below. [Table 2]

[0105] Step 1: Liquefaction: Add 150 L of water to the bioreactor, heat to 80-85°C, and adjust the pH to 5.5-6.0 by adding 0.05% citric acid. Add 0.5-1.0 kg of alpha-amylase enzyme (e.g., Connell Alpha Classic) per tonne of oats.

[0106] Turn on the agitator and slowly add the ground oat flour (20-30% solids based on viscosity). Hold in the tank for 1-2 hours until a starch-iodine test is negative.

[0107] Step 2 Saccharification: The temperature is reduced to 60-65°C, and then GA400 α-amylase enzyme (Connell) is added at 0.5 kg per tonne of oats weight.

[0108] The mixture is held in the tank for 1-3 hours depending on the desired flavor profile.

[0109] It is then cooled to 5-25°C for 30 minutes (or until the desired temperature is reached) and the pH is adjusted to approximately 6.0.

[0110] The resulting slurry is then passed through degassing and HPH stages as described above to produce an oat concentrate with cell rupture at first / second stage pressures of 1200 bar and 0 bar, respectively.

[0111] The product is off-white, creamy in color, with a nutty, sweet oat aroma and a nutty oat flavor with a sweet aftertaste. The texture is smooth and of medium consistency.

[0112] Example 2 - Oat Milk Product An oat milk product can then be made from the oat concentrate according to the ingredient list in Table 3 below. [Table 3]

[0113] Add the oats, water, calcium carbonate, dipotassium phosphate, and salt to a blender and blend until well emulsified. While blending with a high-shear blender, add the coconut oil to the mixture.

[0114] Heat to 95°C for 5 minutes, then decant into an airtight container and store below 4°C.

[0115] The properties of the resulting oat milk are excellent, particularly with regard to its foaming ability, indicating that the oat grain proteins are effectively extracted from the cells with less detrimental effects on its functionality than with conventional production methods. The oat milk has a very good flavor, providing an excellent alternative to currently available oat milks on the market.

[0116] It will be understood by those skilled in the art that the above-described embodiments are merely examples of how the inventive concept may be implemented. It will be understood that other embodiments, while differing in their details, may nevertheless be considered to be within the scope of the same inventive concept and to represent the same invention.

Claims

1. 1. A process for carrying out lysis of cells of a plant material or part thereof, said process comprising: obtaining the plant material at a target particle size; combining the plant material in a fluid medium in a container; exposing the plant material to a series of predetermined treatment conditions; degassing the plant material to substantially reduce or remove entrained gases; introducing the plant material into a two-stage compression device in which the plant material is subjected to a first pressure in a first stage of high fluid pressure compression followed by a second pressure in a second stage of rapid decompression, wherein the first pressure is substantially greater than the second pressure, thereby subjecting the plant material to cavitation of water within cell walls, causing cell wall rupture.

2. 10. The process of claim 1, wherein the target particle size of the plant material is in the range of 400 to 2000 microns.

3. 10. The process of claim 1, wherein the set of predetermined processing conditions depends on the raw materials used and includes one or more of temperature, temperature profile, pH, viscosity, and time.

4. 4. The process of claim 3, wherein the set of predetermined processing conditions comprises a temperature of less than 60°C.

5. 10. The process of claim 1, wherein the degassing and compaction processes occur simultaneously via partial recirculation of compacted material from an outlet of a degassing device back into the vessel.

6. 2. The process of claim 1, wherein the first pressure is between 400 bar and 3000 bar.

7. 7. The process of claim 6, wherein the first pressure is between 900 bar and 2000 bar.

8. 2. The process of claim 1, wherein the second pressure is between atmospheric pressure and 400 bar.

9. 9. The process of claim 7 or 8, wherein the ratio of the first pressure to the second pressure is 4:1 or greater.

10. 10. The process of claim 1, wherein the first pressure is approximately 900 bar and the second pressure is approximately 200 bar.

11. 10. The process of claim 1, wherein the first pressure is in the range of approximately 600 to 1500 bar and the second pressure is in the range of approximately 0 to 350 bar.

12. 10. A process according to any one of the preceding claims, wherein the degassing device comprises a substantially vertical pressure vessel having an outer tube and an open inner annular tube, the inner tube extending from an inlet end of the degassing device for 65% to 75% of the length of the outer tube, and wherein the plant material entering the degassing device is directed towards the interior of the inner tube.

13. 1. A two-stage high fluid pressure compression device for performing lysis of cells of plant material, said device comprising: a first step for subjecting the plant material to a first pressure; a second step for exposing the plant material to a second pressure substantially lower than the first pressure; The device wherein the pressure difference between the first and second stages causes cavitation of water within the cell walls of the plant material, leading to cell wall rupture.

14. The device of claim 13, wherein the first pressure is between 400 bar and 3000 bar.

15. The device of claim 14, wherein the first pressure is between 900 bar and 2000 bar.

16. The device of claim 13, wherein the second pressure is between atmospheric pressure and 400 bar.

17. 17. The device of claim 15 or 16, wherein the ratio of the first pressure to the second pressure is 4:1 or greater.

18. 14. The device of claim 13, wherein the first pressure is approximately 900 bar and the second pressure is approximately 200 bar.

19. 14. The device of claim 13, wherein the first pressure is in the range of approximately 600 to 1500 bar and the second pressure is in the range of approximately 0 to 350 bar.

20. 14. The device of claim 13, wherein the two-stage high fluid pressure compression device is coupled at its inlet to a degassing device comprising a substantially vertical pressure vessel having an outer tube and an open inner annular tube, the inner tube extending from the inlet end of the device for 65% to 75% of the length of the outer tube, and the plant material entering the device is directed toward the interior of the inner tube.

21. 1. A food product comprising plant material treated by a method, said method comprising: obtaining the plant material at a target particle size; combining the plant material in a fluid medium in a container; exposing the plant material to a series of predetermined treatment conditions; degassing the plant material to substantially reduce or remove entrained gases; introducing the plant material into a two-stage compression device in which the plant material is subjected to a first pressure in a first stage of high fluid pressure compression followed by a second pressure in a second stage of rapid decompression, wherein the first pressure is substantially greater than the second pressure, thereby subjecting the plant material to cavitation of water within cell walls, causing the cell walls to rupture.

22. 22. The food product of claim 21, wherein the target particle size of the plant material is in the range of 400 to 2000 microns.

23. 22. The food product of claim 21, wherein the first pressure is between 400 bar and 2000 bar and the second pressure is between atmospheric pressure and 400 bar.

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