NL2014624A - Method for manufacturing a moulded fiber product, such as an egg packaging, from a biomass material of plant origin, and such moulded fiber product. - Google Patents

Abstract

The present invention relates to a method for manufacturing a mould fiber product, such as an egg packaging, from a biomass material of plant origin and such moulded fiber product. The method according to the invention comprises the steps of: providing a biomass with biomass fibers to a reactor; preparing a slurry comprising the biomass fibers; adding an amount of enzymes to the slurry and performing enzymatic fibrillation of the fibers and/or protein removal; and performing a moulding operation with the slurry comprising the fibrillated fibers to manufacture the moulded fiber product.

Description

METHOD FOR MANUFACTURING A MOUFDED FIBER PRODUCT, SUCH AS AN EGG PACKAGING, FROM A BIOMASS MATERIAL OF PLANT ORIGIN, AND SUCH

MOULDED FIBER PRODUCT

The present invention relates to a method for manufacturing a moulded fiber product. Such moulded fiber product may comprise packaging products, such as a packaging for eggs and similar products like kiwis and tomatoes, for example.

Conventional packaging products from moulded fiber material originating from a paper material also referred to as paper pulp. In case such conventional packaging is used as an egg packaging unit eggs are transported and displayed on shelves in supermarkets, for example. Consumers do not always appreciate the attractiveness or esthetical appearance of such packaging unit. Furthermore, packaging units manufactured from moulded fiber products depend on the availability of paper material that can be used to provide the moulded pulp.

The present invention has for its object to obviate or at least reduce one or more of the above stated problems in conventional methods for manufacturing a moulded fiber product, in particular a packaging unit for egg cases or egg cartons, for example.

For this purpose the present invention provides a method for manufacturing a moulded fiber product, such as an egg packaging, from a biomass material of plant origin, the method according to the invention comprising the steps of: providing a biomass with biomass fibers to a reactor; preparing a slurry comprising the biomass fibers; adding an amount of enzymes to the slurry and performing enzymatic fibrillation of the fibers and/or protein removal; and performing a moulding operation with the slurry comprising the fibrillated fibers to manufacture the moulded fiber product.

Preparing a slurry comprising biomass fibers of plant origin for a moulding operation to manufacture a moulded fiber product, such as an egg packaging, results in a slurry having a protein content of above 10% and even higher. Such high protein content hinders dewatering, increases foaming and odour production. Also, high protein content may reduce the (hydrogen) bonding in the material, thereby possibly reducing the strength/stiffness of the packaging unit.

Providing an amount of enzymes for enzymatic fibrillation of the fibers and/or protein removal by adding an amount of enzymes enables performing enzymatic fibrillation of the fibers in the slurry. In fact, adding the enzymes enables enzymatic hydrolysis facilitating the fibrillation of the biomass fibers originating from plants. Preferably, fibrillation due to the enzymatic reaction enhances fiber bonding without significantly reducing pulp viscosity. In addition, enzymatic treatment improves dewatering of the moulded product in the manufacturing process. This reduces the required drying energy and/or drying time for the moulded fiber product.

As a further effect of manufacturing moulded fiber products, particularly a packaging unit, from a biomass material of plant origin improves the flexibility of possible raw materials used for such products. In addition, the use of biomass of plant origin improves the natural feel for the consumer. Also, especially in case the biomass of plant origin originates from a rest flow, the sustainability of the packaging unit manufactured with the method according to the invention is further enhanced. As a further effect of using biomass material of plant origin is the reduction of the amount of mineral oils in the resulting moulded fiber product. These mineral oils are used in printing ink of recycled paper material involving components like MOSH (Mineral Oil Saturated HydroCarbon) and MOAH (Mineral Oil Aromatic HydroCarbon). More specifically, these mineral oils are used as solvent in printing inks used for printing paper and board packaging and end up in recycled paper grades that are used by the paper industry and moulded fiber industry.

In a presently preferred embodiment the biomass of plant origin is responsible of 10 wt% of the moulded pulp fiber product, preferably at least 20 wt%, more preferably at least 50wt%, even more preferably at least 80 wt%, even more preferably at least 85 wt%, and most preferably at least 92.5 wt.%. Preferably, this biomass of plant origin comprises so-called non-wood biomass, more particularly non-wood lignocellulosic biomass. This further improves the natural feel and sustainability of the resulting packaging unit.

The biomass of plant origin may involve plants from the order of Poales including grass, sugar cane, bamboo and cereals including barley and rice. Other examples of biomass of plant origin are plants of the order Solanales including tomato plants of which the leaves and/or stems could be used, for example plants from the Order Arecales including palm oil plants of which leaves could be used, for example plants from the Order Maphighiales including flax, plants from the Order of Rosales including hemp and ramie, plants from the Order of Malvales including cotton, kenaf and jute. Alternatively, or in addition, biomass of plant origin involves so-called herbaceous plants including, besides grass type plants and some of the aforementioned plants, also jute, Musa including banana, Amarantha, hemp, cannabis etcetera, preferably, the (lignocellulosic) biomass of plant origin comprises biomass originating from plants of the Family of Poaceae (to which is also referred to as Gramineae). This family includes grass type of plants including grass and barley, maize, rice, wheat, oats, rye, reed grass, bamboo, sugar cane (of which residue from the sugar processing can be used that is also referred to as bagasse), maize (corn), sorghum, rape seed, other cereals, etc. Especially the use of so-called nature grass provides good results when manufacturing packaging units such as egg packages. Such nature grass may originate from a natural landscape, for example. This family of plants has shown good manufacturing possibilities in combination with providing a sustainable product to the consumer.

In a presently preferred embodiment according to the present invention, the enzymes for performing the enzymatic fibrillation comprise hydrolases.

The use of a hydrolase catalyses the hydrolysis of a chemical bond of the biomass fibers. The hydrolases that are added to the slurry act upon these bonds of the fibers, thereby improving the characteristics of the material for a moulding operation.

Preferably, the hydrolases comprise proteases that are an enzyme capable of performing proteolysis. The proteases may comprise so-called serine proteases, threonine proteases, cysteine proteases, aspartate proteases, flumatic acid proteases, and metalloproteases. Proteases cut proteins in amino acids and/or peptides, thereby obviating the negative effects of the protein on the moulding operation and not hindering the dewatering.

In a further preferred embodiment according to the invention the enzymes comprise cellulase. Cellulases further de-fiber the biomass involving enzymatic fibrillation, thereby further increasing the bonding surface achieving an improved strength of the end products. Cellulases may involve endo-cellulase, exo-cellulase with optimally cellobiase, for example. Preferably, the enzymes comprise both proteases and cellulases.

In a further preferred embodiment according to the invention the enzymes comprise pectinase. Pectinases break down pectin. Pectin is typically found in cell walls. These pectic enzymes may include one or more of the following enzymes, pectolyase, pectozyme and polygalacturonase. Preferably, the enzymes comprise proteases, cellulases and pectinases. Such mixture provides optimal results for the manufacturing process of the moulded fiber product.

The method according to the invention can be applied directly to a biomass or after pre-treatments), including chopping of the biomass fiber material and flushing/cleaning the biomass material to remove sand, stones, and other contaminations in the biomass.

In a presently preferred embodiment according to the invention the slurry comprises a protein content below 6 dry wt%, preferably below 4 dry wt%, more preferably below 3 dry wt%, even more preferably below 2 dry wt%, and most preferably below 1.75 dry wt%.

Having a low protein content in the biomass, preferably below 2 dry wt%, reduces foaming and problematic dewatering of the pulp, thereby resulting in lower manufacturing speed and higher drying costs for the wet product. It may also improve strength and stiffness of the final packaging unit. Dry protein content can be derived by measuring the Nitrogen-Kjeldahl content with e.g. a Buchi N-Kjeldahl lab analysis. From the N-Kjeldahl analysis the protein content in the original biomass sample or packaging can be calculated.

In a presently preferred embodiment, the method according to the invention further comprises pre-treating the biomass. The enzymes are only added after the pre-treatment has been performed. Besides chopping and flushing/washing/cleaning the biomass, pre-treatment may comprise aerobic digestion of the biomass. Preferably, the aerobic digestion is performed by micro-organisms naturally appearing and/or on the biomass material. This aerobic digestion is for example performed involving preparing a slurry by dispersing the biomass material in an aqueous liquid and exposing the slurry to conditions suitable for aerobic digestion by the micro-organisms. After the digestion process the biomass product can be provided to the aforementioned treatment involving the enzymatic fibrillation with the added amount of enzymes. This pre-treatment process is shown to be effective in the removal of undesirable component in the biomass, including carbohydrates, for example.

Alternatively, or in addition thereto, other pre-treatment steps are performed. These treatments may include exertion of strong mechanical forces and heat to the biomass. Besides chopping, also grinding, milling or cutting can be performed to reduce the biomass material. Also, pre-treatment may involve mixing the biomass with other biomass material. Micro-organisms capable of performing the pre-treatment may involve bacteria, yeast and moulds, or combinations thereof, including lactic acid bacteria for example. Suitable conditions for the aerobic digestion involves a temperature of at least 5°C, preferably at least 15°C and preferably the temperature is above 20°C. The pressure is preferably in the range of 0.5-5 bar, preferably in the range of 0.75-3 bar. The digestion process may take more than 0.5 hours, and is preferably in the range of 1-48 hours, more preferably in the range of 2-24 hours.

In a further preferred embodiment, the pre-treating comprises a refining step. The refining process may involve a so-called refiner that performs the milling or cutting process. Preferably, the refiner comprises a number of plates that move relative to each other thereby mechanically cutting the biomass material. The distance between such plates determines the (average) length of the biomass fibers.

In a presently preferred embodiment according to the invention the pre-treating comprises a first and second refining step. The second refining step provides an additional refining of the biomass fibers. This may involve a smaller distance between the plates of the refiner.

Experiments showed a significant improvement of the strength and stability of the final moulded fiber product. Furthermore, the use of a second refining step significantly increased the quality of the final product, involving a significant reduction in the variance of the strength.

The refining step improves the manufacturing process of the fiber pulp in a moulding process. For example, the refining step(s), comprising cutting and milling of the fibers, leads to fibrillation of the grass fibers/biomass fibers (and/or paper fibers), which leads to improved fiber-fiber bonding. During refining steps the cutting, milling and fibrillation causes a further decrease of the Zeta-Potential in the range of -10 to -30mV. The lower Zeta potential encourages the fibers to bind cationic charged additives like dry strength agents, starches and other paper making additives. This increases the manufacturing possibilities for the biomass / paper pulp and enables manufacturing mechanically stronger and stiffer moulded fiber products.

In a presently preferred embodiment according to the invention the biomass comprises natural grass. Such natural grass of nature grass may originate from a natural landscape, for example. This grass material has shown good manufacturing possibilities in combination of providing a sustainable product with a desired visual appearance to the consumer.

In a further preferred embodiment according to the present invention the biomass comprises Miscanthus.

The use of Miscanthus in the biomass material provides additional strength to the final mould fiber product. Optionally, the biomass material substantially comprises Miscanthus. Alternatively, Miscanthus is mixed with other biomass material. Also, the biomass material, optionally including a mixture of natural grass and Miscanthus, is mixed with paper pulp for the manufacture of moulded fiber products, such as egg packaging units. Miscanthus has relatively long fibers with a relatively high cellulose content of up to 85%. Pre-treatment may involve a refinement step. In a presently preferred embodiment, the slurry mixture that is used in the manufacturing process produces a moulded fiber (packaging) product comprising 10-60 wt% of paper pulp and 40-90 wt% biomass pulp. Preferably, the biomass pulp comprises 25-75 wt% natural grass, 0-50 % Miscanthus and paper pulp.

The presently preferred embodiment according to the present invention the method further comprises the step of providing a binding agent to the slurry.

By providing a binding agent improves the strength of the final packaging product. More specifically, the binding agent comprises a dry strength agent, preferably a cationic charged polymer, such as Bim DS 2801, Bim DS 2858, Xelorex B 2000, Hercobond 6335, Hercobond LI220, Fennobond 4000. The dry strength agent improves strength, stiffness and mechanical properties of the packaging unit. Alternatively, or in addition to the dry strength agent, the binding agent comprises a dewatering polymer, preferably also with a cationic charge and stimulating flocculation by binding with the anionic charged (biomass) fibers, such as Bim DS 2855, Perform PC532L, Perform SP7200, Perform PK2350. The dewatering polymer improves improving dewatering of the moulded fiber material in the moulding process. Furthermore, this increases the dry weight content of the packaging unit and/or reduces the energy required for the drying operation of the packaging unit.

In a further preferred embodiment according to the present invention, the method further comprises the step of adding potato fibers to the slurry.

By providing additional potato fibers to the slurry the final strength of the packaging product is increased. Preferably, fibers resulting from the potato starch extraction process in the starch industry are added to the slurry. The potato skin is removed during this extraction process, and the residual waste stream comprising of potato skin fibers still contains native potato starch granules that can be mixed with biomass and/or paper fibers in the moulded fiber production process. In the pulp mixing step, and the drying step following the moulding step, the starch granules tend to gelatinize and enhance the fiber-fiber bonding with improved product stiffness as a result. Therefore, preferably the potato slurry comprises potato skin fibers with residual starch granules. Tests have shown a 5-15% increase in mechanical properties like tensile strength, burst index, 3 point bending stiffness and compression strength etc. Optionally, the potato fibers are mixed with Miscanthus and a natural grass. This mixture can be mixed with conventional paper pulp after which the final mixture is used for manufacturing the packaging unit.

The invention further also relates to a moulded fiber product comprising biomass fibers of plant origin that is manufactured according to the method involving one or more of these steps as earlier described.

Such moulded fiber product provides the same effects and advantages as described with respect to the method. This moulded fiber product specifically includes packaging units for products like eggs, kiwis and tomatoes. In particular, the use of the packaging unit as an egg packaging units showed good results in view of strength, visual appearance and sustainability.

Preferably, the moulded fiber product comprises a number of reinforcement elements. Using one or more reinforcement elements improves the stability of the packaging unit.

Especially when using a higher amount of non-wood biomass, preferably plants of the Family of Poaceae, more specifically grass type plants such as so-called natural grass, mechanical properties of the packaging unit according to the invention start to become limiting. Providing the packaging unit with reinforcement elements, such as ribs, grooves, protrusions, etc., improves the mechanical properties including strength, stability, tensile strength, three-point bending stiffness and compression etc. This enables the use of a higher amount of (non-wood) biomass. More specifically, this enables the use of an amount above 80 wt. %, more preferably above 85 wt. % is possible. Preferably, the use of reinforcement elements allows for the use an amount above 92.5 wt. %. This provides a sustainable packaging unit with a natural feel and has good mechanical properties both in the manufacturing process and its actual use.

In a presently preferred embodiment the reinforcement elements comprise a number of ribs extending over at least a front surface of the bottom part. This rib or these ribs strengthen the front surface of the bottom part. This improves the manufacturing process and the strength of the packaging unit according to the invention in use.

In an embodiment according to the invention the packaging unit further comprises a cover part configured for engaging the bottom part, wherein the cover part comprises reinforcement elements to increase stability of the packaging unit. Preferably the cover part comprises top, front, side and rear surfaces with the front surface preferably comprising one or more openings configured for receiving the first locking element, such as a notch, cam or protrusion provided on the bottom part, in a closed position of the packaging unit. Having a packaging unit with a bottom part and a cover part enables transport and display of products without damaging the products. This is especially relevant in case of vulnerable products like eggs. In a preferred embodiment, the cover part is hingedly connected to the bottom part on the rear side thereof. On the front side a lock is provided comprising the first locking element on the bottom part and an opening in the cover part as second locking element that is configured for receiving the first locking element.

Preferably, the reinforcement elements comprise a number of ribs and/or grooves extending over at least a front surface of the cover part. Optionally, these elements extend from the top surface of the cover part to the front surface of the cover part, thereby further improving the mechanical properties of the packaging unit.

In a presently preferred embodiment according to the invention the packaging unit further comprises visible (non-wood) biomass fibres protrude from a package surface to such an extent that separate visible (non-wood) biomass fibres can be distinguished by sight and/or touch.

Providing distinguishable fibres contributes to the natural and/or sustainable feel for the consumer when confronted with such embodiment of the packaging unit according to the invention.

Preferably, the protruding fibres are arranged to provide a cushioning effect for products placed in the compartments. The cushioning effect reduces the risk of product damage during transport and/or display of the products. This is especially relevant when dealing with vulnerable products such as eggs. This effect may be enhanced by locally allowing a lower mechanical strength providing some flexibility to the packaging unit, especially in or around a product compartment thereof. This may reduce product damage.

Further advantages, features and details of the invention are elucidated on a basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which:

Fig. 1 shows a method according to the invention;

Fig. 2 shows a packaging unit according to the invention;

Fig. 3 shows the packaging unit of figure 2 without label with reinforcement elements;

Fig. 4 shows the packaging unit of figure 3 in an open position;

Figs. 5, 6 and 7 show a top, side and front views of the packaging unit of figure 2;

Fig. 8 shows a detail of the packaging unit of figure 7; and

Fig. 9 shows a detail of the packaging unit of figure 8.

Manufacturing method 2 (figure 1), comprises collecting step 4 wherein biomass material is collected. This collected biomass material is cut or chopped in chopping operation 6 and washed in washing step 8 involving a sorting drum, for example. In a preferred embodiment, washing step 8 includes the use of an additional cyclone or so-called HD-cleaner to further separate the biomass from other materials.

In refinement step 10 the biomass material is refined in one, two or more refining steps. In a presently preferred embodiment, refinement step 10 involves refining the biomass fibers with a consistency in the range of 3-5% in a disc refiner. Refining step 10 cuts or chops the biomass fibers, and fibrillates a part of the biomass fibers. This increases the bonding surface and fibers can be provided with a charge (negative, anionic). This enables the fibers to build hydrogen bonds to other fibers and/or to cationic polymers, such as polyacrylamides, that stimulate flocculation and improving dewatering in the moulding operation. Optionally, these polymers are dosed at the beginning of the actual moulding operation.

Optionally, in digestion step 12 aerobic digestion is performed on the biomass material. Preferably, the aerobic digestion is performed with micro-organisms that are already present at or on the biomass. Optionally, additional micro-organisms are added to the material to accelerate the biologic cracking and/or digestion. From digestion step 12 liquid rest flow 14 with proteins, sugars and pectins is removed from the system. This prevents these components to negatively influence the moulding operation. Rest flow 14 is treated, for example involving reverse osmose, membrane filtration and/or other operations to concentrate rest flow 14. As a further step, the concentrated rest flow can be used to produce biogas. In an advantageous embodiment according to the invention, after removal of sulphurous components, the biogas is used in the drying step of the moulding operation. Alternatively, or in addition thereto, rest flow 14 can be used for the production of so-called bio-plastics such as PLA, PHA and/or PHB.

The remaining slurry 16 with clean, and preferably de-fibred, biomass fiber material is treated in enzymatic treatment step 18 to further reduce the amount of protein. In enzymatic treatment step 18 an amount of enzymes 20 is added to slurry 16. Enzymes 20 preferably comprise an amount of proteases and/or cellulases. Proteases cut proteins in amino acids and/or peptides, thereby obviating the negative effects of the protein on the moulding operation and not hindering the dewatering. Cellulases further de-fiber the biomass involving enzymatic fibrillation, thereby further increasing the bonding surface achieving an improved strength of the end products. Optionally, in enzymatic treatment step 18 pH is controlled to optimise enzymatic operation.

Treated slurry 22 is optionally diluted or concentrated/thickened in consistency step 24 to achieve the desired consistency of the material for the moulding operation. In mixing step 26 optionally paper pulp 28 is mixed with the slurry and the moulding process 30 can be started. Alternatively, treated slurry 22 is concentrated/thickened at a dry solids weight content of 45-60%, for example, to enable transport and storage of the material. This may involve the use of a pressing screw and/or belt dryer. This enables the use of the material in other production plants and/or buffering the material thereby rendering the entire process more flexible.

In moulding process 30 optionally retention or dewatering stimulating agents can be dosed to increase the dry content of the product thereby reducing energy demands in the drying step.

Alternatively, or in addition thereto, dry and/or wet strength agents can be dosed to improve stiffness and stability of the product and/or improve mechanical product properties, such as tensile strength, bending stiffness, compression strength etc. Finally, moulding operation 30 results in moulded fiber products 32. A packaging unit 102 (Figures 2, 4-8) comprises a bottom part 104 with a front surface 106, two side surfaces 108, a back side 110, and a bottom side 112. In the illustrated embodiment, a cover part 114 is hingedly connected with hinge 116 to bottom part 104 to allow cover part 114 to move relatively to bottom part 104 between an open and a closed position. Cover part 114 further comprises front surface 118, two side surfaces 120, a back side surface 122 and a top surface 124.

On the inside of bottom part 104 product receiving compartments 126 are provided having contours matching at least partially the outer contours of the products, like eggs, kiwis and tomatoes, for example. Support cones 128 are provided to add stability and strength to packaging unit 102. Lock 130 comprises opening 132 in cover part 114 and cam 134 of bottom part 104. Furthermore, packaging unit 102 is provided with label 136.

The package 101 is made from moulded fibre containing a substantial amount of grass fibres, for example 50%, or 80%, or 90% or 95%.

Reinforcing elements (Figure 3) comprise a groove 138 with starting position 140 at top 124 of cover part 114 and ending position 142 at front surface 118 of cover part 114. Alternative reinforcing elements that may be applied in combination with grooves 138 comprise strengthening rods, rims and/or protrusions 144. Groove 138 comprises side wall 146 (Figure 9).

Fibres 48 (Figure 3), in the illustrated embodiment grass fibres, are provided in the packaging material. Some of the (grass) fibres 150 may protrude from a package surface (Figure 4), including the surface of compartment 126, that protrude to such an extent that separate (grass) fibres can be distinguished by sight and/or touch. In compartment 126 protruding fibres 150 provide a cushioning effect that may further contribute to the reduction of product damage.

These longer (grass) fibres 148, 150 have a length of about 25 mm. The longer (grass) fibres 148, 150 have a length such that the fibres are able to float on a fibre pulp or pulp mix during manufacturing, which enables that during moulding these long fibres are positioned at the package surface. These protruding fibres 150 even more improve the appealing effect of the package 101. Fibres 150 protrude even more from a package inside surface also because that inside surface is determined by the suction side of a mould. This suction side of a mould is a well known concept in manufacturing a moulded fibre food packaging.

Other pre-treatment steps that optionally can be performed may include soaking the biomass in water or soaking for a period of 1-2 days, for example. The refining may comprise a number of so-called plates or disks that are arranged at a mutual distance between 0.5 and 2 mm.

An example of such a refiner is a Sprout-Waldron disk refiner. Optionally, in the manufacturing process coloring agents and/or pigments can be added. Also other agents and/or pigments can be added, for example dewatering polymers.

The present invention is by no means limited to the above described preferred embodiments thereof. The rights sought are defined by the following claims within the scope of which many more modifications can be envisaged. For example, the packaging unit that is manufactured according to the presented method can be applied to eggs and other vulnarable food and/non-food products as well as to other products. Non-limiting examples of products include eggs, vegetables, fruit, electronic products such as DVD, radios, displays, mobile phones, tablets etc.

Clauses 1. Method for manufacturing a moulded fiber product, such as an egg packaging, from a biomass material of plant origin, comprising the steps of: providing a biomass with biomass fibers to a reactor; preparing a slurry comprising the biomass fibers; adding an amount of enzymes to the slurry and performing enzymatic fibrillation of the fibers and/or protein removal; and performing a moulding operation with the slurry comprising the fibrillated fibers to manufacture the moulded fiber product. 2. Method according to clause 1, wherein the enzymes comprise a hydrolase. 3. Method according to clause 2, wherein the hydrolase comprises protease. 4. Method according to clause 1, 2 or 3, wherein the enzymes comprise cellulase. 5. Method according to one or more of the foregoing clauses, wherein the enzymes comprise pectinase. 6. Method according to one or more of the foregoing clauses, wherein the slurry comprises a protein content below 6 dry wt%, preferably below 4 dry wt%, more preferably below 3 dry wt%, even more preferably below 2 dry wt%, and most preferably below 1.75 dry wt%. 7. Method according to one or more of the foregoing clauses, further comprising pre-treating the biomass. 8. Method according to clause 7, wherein pre-treating comprises aerobic digestion of the biomass. 9. Method according to clause 8, wherein the aerobic digestion is performed by microorganisms naturally occurring in and/or on the biomass material. 10. Method according to clause 7, 8 or 9, wherein pre-treating comprises a refining step. 11. Method according to one or more of the foregoing clauses, wherein the biomass comprises natural grass. 12. Method according to one or more of the foregoing clauses, wherein the biomass comprises Miscanthus. 13. Method according to one or more of the foregoing clauses, further comprising the step of providing a binding agent to the slurry, the binding agent comprising a dry strength agent and/or a dewatering polymer. 14. Method according to one or more of the foregoing clauses, further comprising the step of adding potato fibers to the slurry. 15. Moulded fiber product comprising biomass fibers that is manufactured according to one or more of the foregoing clauses. 16. Moulded fiber product according to clause 15, further comprising a number of reinforcement elements.

Claims (16)

A method for manufacturing a shaped fiber product, such as an egg package, from a biomass material of vegetable origin, comprising the steps of: providing a biomass on a reactor; preparing a slurry comprising biomass fibers; adding an amount of enzymes to the slurry and performing enzymatic fibrillation of the fibers and / or protein removal; and performing a forming operation with the slurry comprising the fibrillated fibers to produce the formed fiber product. The method of claim 1, wherein the enzymes comprise a hydrolase. The method of claim 2, wherein the hydrolase comprises a protease. The method of claim 1, 2 or 3, wherein the enzymes comprise a cellulase. The method of any one of the preceding claims, wherein the enzymes comprise a pectinase. A method according to any one of the preceding claims, wherein the slurry comprises a protein content of less than 6% by weight of dry matter, preferably less than 4% by weight of dry matter, more preferably less than 2% by weight of dry matter, most preferably, less than 1.75% by weight of dry matter. The method according to one or more of the preceding claims, further comprising pre-treating the biomass. The method of claim 7, wherein the pretreatment comprises aerobic decomposition of the biomass. The method of claim 8, wherein the aerobic decomposition is performed by microorganisms that occur naturally in and / or on the biomass material. The method of claim 7, 8 or 9, wherein the pretreatment comprises a refining step. The method according to one or more of the preceding claims, wherein the biomass comprises natural grass. The method of any one of the preceding claims, wherein the biomass comprises Miscanthus. A method according to any one of the preceding claims, further comprising the step of providing a binding agent on the slurry, wherein the binding agent comprises a dry strength agent and / or a dewatering polymer. A method according to any of the preceding claims, further comprising the step of adding potato fibers to the slurry. A shaped fiber product comprising biomass fibers and manufactured according to one or more of the preceding claims. The shaped fiber product of claim 15, further comprising a plurality of reinforcement elements.