Bonding composition for binding an alginate coating to a vegetarian or vegan foodstuff

Abstract

The invention relates to a bonding composition for binding an alginate casing or coating to a vegetarian or vegan foodstuff. The composition comprises, on a dry matter basis; 0.5045 wt.% of one or more hydrocolloid gelling agents, including at least alginate; 1.035 wt.% of one or more water binding agents; and one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein. The bonding composition comprises 0.2580 wt.% of alginate. It has the function of providing adhesion between the coating and the foodstuff. In this capacity, it is present as an intermediate adhesive layer that is positioned in between the foodstuff and the coating. There is a first bond between the intermediate adhesive layer and the foodstuff, relying on coagulated protein; and there is a second bond between the intermediate adhesive layer and the coating, relying on the gelling of alginate. In this way, the coating is strongly connected to the foodstuff; no bursting or delamination takes place during heating. The foodstuff is in particular a vegan or vegetarian sausage.

Description

[0001] BONDING COMPOSITION FOR BINDING AN ALGINATE COATING TO A VEGETARIAN OR VEGAN FOODSTUFF

[0002] FIELD OF THE INVENTION

[0003] The invention relates to a bonding composition for binding an alginate coating to a vegetarian or vegan foodstuff, to a method for coating a vegetarian or vegan foodstuff with a layer of gelled alginate and to a vegetarian or vegan foodstuff comprising a gelled alginate coating.

[0004] BACKGROUND

[0005] It is common practice in the food industry to provide foodstuffs with a casing or coating. For example, sausages are prepared by coating a meat dough or another sausage material. Conventional meat sausages have animal derived casings such as intestine or collagen. However, due to their animal origin, such casings cannot be used for vegan or vegetarian foodstuffs. As an alternative, anionic polysaccharides such as alginate are often used as a coating agent. The term "alginate" refers to a group of naturally occurring polysaccharides extracted from seaweed, and are therefore not animal-derived. They can form gels relatively easily in the presence of alkaline earth metals such as magnesium and calcium. Such alginate gels can very well serve as a coating on a foodstuff.

[0006] Alginate casings and coatings have advantageous properties such as a high strength and the ability to provide sausages with a taste, texture and mouthfeel that is comparable to that of sausages enclosed in a conventional animal-derived casing. Such alginate casings are for example described in EP3732980A1 . The casings described are obtained as such. They are pre-formed and self-supporting casings that can be used to wrap foodstuff at a later stage, possibly by performing further steps such as sewing, gluing, welding or vulcanizing.

[0007] However, vegan and vegetarian sausage materials do not adhere very well to casings that are made from anionic polysaccharides such as alginate. In particular, when a sausage in an alginate casing is heated in water (an action commonly performed by the end-consumer), there is often accumulation of water between the sausage material and the coating, making the sausage prone to delamination.

[0008] For example, WO9955165A1 describes a sausage with an edible skin (i.e. coating) comprising alginate and protein. It is prepared by extruding a proteinaceous composition together with the alginate, which alginate is then gelled upon contact with an aqueous calcium dichloride solution. The document is however silent on any adhesion of the coating to the proteinaceous composition. Indeed, it appears that the procedure does not lead to any substantial bonding between the two components.

[0009] Another approach is to use a separate binding composition that acts as an adhesive portion between a sausage material and a coating, but this has not yet provided a satisfactory solution to the lack of adhesion that is observed for anionic polysaccharides such as alginate.

[0010] The casings described in EP3732980A1 , which document is referenced hereabove, are neither satisfying, since they are pre-formed ( / .e. manufactured prior to encasing foodstuff). Therefore, they are more suitable as a vegan or vegetarian alternative to preformed collagen or natural casings. Moreover, using a such a sheath for the coating of a foodstuff makes it difficult to generate an acceptable adhesion between both. A separate bonding composition can for example not easily be applied between the casing and the foodstuff.

[0011] Other solutions in the art rely on modification of the foodstuff itself in order to improve its adhesion to the coating an / or to an intermediate adhesive portion. This is however undesired, since this goes often at the expense of the taste, organoleptic properties, appearance, texture and / or mouthfeel of the entire foodstuff.

[0012] SUMMARY OF THE INVENTION

[0013] It is therefore an object of the present invention to provide an alginate-coated vegan or vegetarian foodstuff that does not suffer from one of the above disadvantages. It is also an object to provide an effective bonding composition for coating a vegan or vegetarian foodstuff with an alginate coating. It is in particular an object of the present invention to provide a method for coating wherein the bonding composition can be chosen independently from the alginate casing or coating. It is also an object that the vegan or vegetarian foodstuff does not need to be adapted to the bonding composition.

[0014] It has now been found that one or more of these objects can be reached by applying a particular bonding composition. Accordingly, in a first aspect the present invention relates to a bonding composition for binding an alginate coating, in particular an alginate casing, to a vegetarian or vegan foodstuff, the bonding composition comprising, on a dry matter basis, the following components a) 0.50-45 wt.% of one or more hydrocolloid gelling agents, including at least alginate; b) 1 .0-35 wt.% of one or more water binding agents, optionally comprising one or more of the same hydrocolloid gelling agents as in component a); c) 20-90 wt.% of one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein; wherein the composition comprises, on a dry matter basis, 0.25-80 wt.% of alginate, in particular sodium alginate.

[0015] In a second aspect, the invention relates to a method for coating a vegetarian or vegan foodstuff with a layer of gelled alginate, comprising the use of a bonding composition of the invention. Such method may in particular comprise

[0016] - providing a vegetarian or vegan foodstuff comprising one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein;

[0017] - providing a bonding composition of the invention;

[0018] - providing an alginate solution in water;

[0019] - providing an aqueous solution of a divalent metal ion;

[0020] - applying to the foodstuff a layer of the bonding composition and a layer of the alginate solution, so that the layer of the bonding composition is positioned in between the foodstuff and the layer of the alginate; thereafter

[0021] - contacting the layer of the alginate solution with the aqueous solution of a divalent metal ion to yield the layer of gelled alginate; thereafter

[0022] - optionally heating the coated foodstuff to a temperature in the range of 40- 120 °C, in particular in the range of 60-100 °C, to generate an intermediate adhesive layer that binds the layer of gelled alginate to the foodstuff. In a third aspect, the invention relates to a vegetarian or vegan foodstuff comprising a gelled alginate coating, wherein

[0023] - the foodstuff comprises one or more proteins selected from the group of proteins derived from plants, proteins derived from fungus, proteins derived from milk and proteins derived from egg; and

[0024] - the coating adheres to the foodstuff.

[0025] Such vegetarian or vegan foodstuff may in particular comprise an intermediate adhesive layer that is positioned in between the foodstuff and the gelled alginate coating, wherein the intermediate adhesive layer comprises, on a dry matter basis, the following components a) 0.50-45 wt.% of one or more hydrocolloid gelling agents, including at least alginate; b) 1 .0-35 wt.% of one or more water binding agents; c) 20-90 wt.% of one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein; wherein alginate constitutes 0.25-80 wt.% of the dry matter of the bonding composition.

[0026] In a fourth aspect, the invention relates to vegetarian or vegan foodstuff obtainable by a method according to the invention.

[0027] BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 schematically displays a cross-section of a first foodstuff according to the invention.

[0029] Figure 2 schematically displays a cross-section of a second foodstuff according to the invention.

[0030] DETAILED DESCRIPTION OF THE INVENTION

[0031] Elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve understanding of various exemplary embodiments of the present invention. In particular, the relative dimensions of a foodstuff, an intermediate adhesive layer and a coating or casing cannot be derived from the figures. Furthermore, the terms “first”, “second”, and the like herein, if any, are generally used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order.

[0032] In the context of the invention, by the term ‘alginate’ is meant an anionic form of alginic acid, wherein the positive counterion is chosen such that the alginate does or does not form a gel. For example, no gel is formed when the counter ion is sodium (alginic acid monosodium salt or, simply, sodium alginate). When sodium alginate is contacted with a divalent metal ion, such as an alkaline earth metal (e.g. magnesium or calcium), the alginate converts into a gel (a ‘gelled alginate’ or an ‘alginate coating’). A skilled person knows which counter ions result in the formation of a gel and which do not.

[0033] In the context of the invention, by the term ‘vegetarian foodstuff’ is meant a foodstuff that lacks any component that is derived from meat or any by-product of animal slaughter such as gelatin or organ tissue.

[0034] In the context of the invention, by the term ‘vegan foodstuff’ is meant a foodstuff that lacks any component that is derived from meat, egg, milk, and any other substance of animal origin.

[0035] In the context of the invention, by the terms ‘plant protein’, ‘fungal protein’, ‘milk protein’ and ‘egg protein’ is meant a protein obtained from or derived from a plant, a fungus, milk or egg, respectively. The plant, fungus, milk or egg protein may have undergone a modification before, during or after obtaining it from the plant, fungus, milk or egg, respectively. For example it may have been modified by cross-linking, (partial) hydrolysis or functional group modification. Fungal protein is also known as ‘mycoprotein’.

[0036] In the context of the invention, by the term ‘hydrocolloid gelling agent’ is meant a polymeric hydrophilic material which is able to gel aqueous systems when present therein at or above a certain minimum concentration.

[0037] In this description, the contents of the different non-volatile components (e.g. salts and nutrients such as carbohydrates, fats and proteins) in a composition may be given on a so-called ‘dry matter basis’. This means that the content of each of these different components is expressed as a proportion of the total dry matter in the composition, typically a weight percentage (wt.%). In this respect, the ‘dry matter’ of a composition is meant to consist of all the constituents of the composition excluding water (and eventual other volatiles, for example ethanol); it is a measurement of the mass of a composition when completely dried.

[0038] The invention relates to a bonding composition for binding an alginate coating to a vegetarian or vegan foodstuff. When the bonding composition is applied as such, it is positioned between the foodstuff and an alginate coating precursor (typically an ungelled alginate composition such as sodium alginate). After the formation of the alginate coating and its concurrent bonding with the foodstuff, the bonding composition is present as an intermediate adhesive layer between the foodstuff and the coating.

[0039] Accordingly, a bonding composition of the invention creates a first bond with the foodstuff and a second bond with the alginate coating. Due to these two bonds, the coating and the foodstuff adhere to one another.

[0040] This is for example demonstrated in Figures 1 and 2, which are crosssections of two different foodstuffs according to the invention; a sausage and a hamburger-type of foodstuff, respectively. In both figures, the foodstuff (1 ) is present as the substance that is to be coated. The foodstuff (1 ) is covered with two layers; an intermediate adhesive layer (2) and a coating (3). The intermediate adhesive layer (2) adheres to the foodstuff (1 ) by means of the first bond and it adheres to the coating (3) by means of the second bond.

[0041] The bonding composition of the invention is designed in such way that the first bond relies on a bonding principle that is different from that of the second bond.

[0042] The first bond involves the interaction of a protein of the foodstuff with the one or more proteins of the bonding composition. In this way, there is no need to include additives in the foodstuff that are essential to creating the first bond. This is an advantage, since such additives are known to modify important properties of the foodstuff, such as taste, organoleptic properties, appearance, texture and / or mouthfeel. It is contemplated that the first bond is formed by the concurrent coagulation of protein(s) of the foodstuff and protein(s) of the bonding composition, which is typically induced by a heating step.

[0043] The second bond involves the interaction of alginate of the coating with alginate of the bonding composition. It is contemplated that both alginates together form a gel when contacted with a divalent metal ion solution, thereby forming a single structure that extends on both sides of the interface between the bonding composition and the coating. In this way, there is no need to include additives in the alginate coating that are essential to creating the second bond. This is an advantage, since such additives may impair the quality of the coating itself.

[0044] A bonding composition of the invention may or may not comprise water; it may comprise up to and including 90 wt.% of water. When the composition is actually applied to a foodstuff in a method for the coating of a vegetarian or vegan foodstuff, the water content is preferably in the range of 60-90 wt.%. For example, it is in the range of 60-80 wt.%, in the range of 70-90 wt.%, in the range of 65-85 wt.%, in the range of 75-90 wt.% or in the range of 75-85 wt.%. This actual application of such bonding composition to a foodstuff may be preceded by diluting a more concentrated bonding composition to any of these water weight percentages.

[0045] In the event that a bonding composition of the invention comprises 60- 90 wt.% of water, then the bonding composition may comprise the following components: a) 0.10-11 .25 wt.% of one or more hydrocolloid gelling agents, including at least alginate; b) 0.20-8.75 wt.% of one or more water binding agents, which may comprise one or more hydrocolloid gelling agents in addition to those of component a); c) 4.0-22.5 wt.% of one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein, in particular 7.0-18 wt.%; d) 60-90 wt.% of water; wherein alginate constitutes 0.050-20 wt.% of the bonding composition.

[0046] In particular, these components may be present in the following weight percentages: a) 1 .50-8.0 wt.%; b) 2.0-7.50 wt.%; c) 4.0-15 wt.%; d) 70-90 wt.%; wherein alginate constitutes 1 .50-12 wt.% of the bonding composition. Alternatively, the components may be present in the following weight percentages: a) 1 .50-8.0 wt.%; b) 2.0-7.50 wt.%; c) 6.0-21 wt.%; d) 70-90 wt.%; wherein alginate constitutes 0.50-12 wt.% of the bonding composition.

[0047] The dry matter of such water-containing bonding compositions comprises components a), b) and c) in principle in the same relative amounts as those in the bonding compositions that are defined on a dry matter basis, and which are described elsewhere in the present description and / or claims.

[0048] The water content of the bonding composition may be substantially lower prior to its actual application, for example during manufacture, transport and / or storage of the bonding composition. It then in fact acts as a precursor to the actually applied bonding composition. Preferably, the water content of the bonding composition is then as low as possible. For example, it is in the range of 0.0-2.0 wt.%, in particular in the range of 0.0-0.20 wt.%. Water may also be substantially completely absent. In such case, the levels of the different components of the bonding composition are substantially the same as those of the composition on a dry matter basis, which composition is described elsewhere in the present description and / or claims.

[0049] Alternatively, the water content of the bonding composition may also be up to 2.5 wt.%, up to 3.0 wt.%, up to 3.5 wt.%, up to 4.0 wt.%, up to 5.0 wt.%, up to 6.0 wt.%, up to 7.0 wt.%, up to 8.0 wt.%, up to 9.0 wt.%, up to 10 wt.%, up to 12 wt.%, up to 15 wt.%, up to 20 wt.%, in the range of 5-50 wt.%, in the range of 10- 60 wt.%, in the range of 10-40 wt.% or in the range of 15-30 wt.%.

[0050] When any such bonding composition is to be applied in a process for the binding of an alginate coating to a vegetarian or vegan foodstuff, then it is typically diluted before its application, preferably to the extent that water constitutes 60-90 wt.% of the bonding composition, more preferably 75-85 wt.%.

[0051] A bonding composition of the invention comprises, on a dry matter basis, 0.50-45 wt.% of one or more hydrocolloid gelling agents. It may also comprise 4-20 wt.% or 1 .0-10 wt.% of one or more hydrocolloid gelling agents, in particular 3.0-8.0 wt.%, on a dry matter basis. The function of these appears to be to stabilize the intermediate adhesive layer. Experiments have demonstrated that the intermediate adhesive layer becomes a slurry when no hydrocolloid gelling agent is present. In addition, it is contemplated that a hydrocolloid gelling agent may also be involved in the actual bonding with the foodstuff.

[0052] Usually, a hydrocolloid gelling agent is a cellulose or a cellulose derivative; in particular a cellulose derivative selected from the group of methyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, methyl ethyl cellulose, and sodium carboxymethyl cellulose. The hydrocolloid gelling agent may also be selected from the group of alginates, carrageenans, agar, gums, dextrans, pectins, glucans, xylans, modified starches, gelatinized starches and gelatin.

[0053] A bonding composition of the invention comprises, on a dry matter basis, 0.25-80 wt.% of alginate. It may also comprise 1 .0-40 wt.% of alginate, in particular 2.0-20 wt.% of alginate, more in particular 3.0-10 wt.% of alginate, on a dry matter basis. The function of the alginate is to realize the second bond, i.e. the bond with the alginate coating. When the alginate coating is in contact with the bonding composition and when a divalent metal ion solution is applied to them, then the alginate of the bonding composition and the alginate of the coating will together form a gel. Extending on both sides of an interface between the bonding composition and the coating, the gel provides the second bond.

[0054] The alginate in a bonding composition of the invention is preferably sodium alginate. It is in principle also possible to use other alginates, such as potassium alginate or lithium alginate.

[0055] The weight average molar mass, Mw, of the dissolved alginate, in particular of dissolved sodium alginate, is usually in the range of 10.000-600.000 kg / mol. It may also be in the range of 30.000-300.000 kg / mol.

[0056] A bonding composition of the invention comprises, on a dry matter basis, 1 .0-35 wt.% of one or more water binding agents. It may also comprise 4.0-30 wt.% of one or more water binding agents, in particular 8.0-25 wt.%, more in particular 10-20 wt.%, on a dry matter basis. The function of these is to bind water during and / or after the bonding of the alginate coating to the foodstuff, i.e. during and / or after the formation of the intermediate adhesive layer. Water that was initially dissolved in the binding composition often cannot dissolve anymore in its entirety in the adhesive layer when a water binding agent is lacking. It may then form a separate phase, which weakens the bonding of the intermediate adhesive layer with the foodstuff and / or with the coating, since it creates areas where there is no bonding. Ultimately, this may lead to bursting and delamination of the coating. This is remedied by including a sufficient amount of the one or more water binding agents in the bonding composition.

[0057] It is herewith understood that the one or more hydrocolloid gelling agents can be chosen such that some or all of them also fall in the category of water binding agent. This is however no problem as long as the quantitative requirements for each of the two types of agents are met. It is emphasized that substances that fall in both categories ( / .e. substances that are a hydrocolloid gelling agent as well as a water binding agent) may be present in the composition in an amount that exceeds 45 wt.%, which is the end value of the content range for the one or more hydrocolloid gelling agents. For example, alginate may be present in an amount of up to and including 80 wt.%.

[0058] Usually, the one or more water binding agents comprises a starch. Preferably, such starch is selected from the group of potato starch, corn starch, rice starch, wheat starch and tapioca starch. The one or more water binding agents may also comprise plant fibers or a hydrocolloid gelling agent. In the event that it comprises a hydrocolloid gelling agent, then this is in addition to the hydrocolloid gelling agent in component a) of the bonding composition. Thus, the dry matter of a composition of the invention may comprise up to and including 80 wt.% of hydrocolloid gelling agent. In a particular case, it includes 80 wt.% of alginate, in particular 80 wt.% of sodium alginate.

[0059] A bonding composition of the invention comprises, on a dry matter basis, 20-90 wt.% of one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein. It may also comprise 40-85 wt.% of the one or more proteins, in particular 50-80 wt.% of the one or more proteins, more in particular 65-80 wt.% and even more in particular 60-75 wt.% of the one or more proteins, on a dry matter basis. The function of the one or more proteins is to realize the first bond, i.e. the bond with the foodstuff. The one or more proteins coagulate with one or more proteins in the vegetarian or vegan foodstuff, typically by a heat treatment. A bonding composition of the invention may in particular comprise, on a dry matter basis a) 4.0-30 wt.% of one or more hydrocolloid gelling agents, including at least alginate; b) 4.0-30 wt.% of one or more water binding agents; c) 40-80 wt.% of one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein; wherein alginate constitutes 3.0-30 wt.% or 4.0-40 wt.% of the dry matter of the bonding composition.

[0060] Usually, the plant protein is derived from a species selected from the group of legumes, vegetables, cereals, nuts and seeds, in particular from a plant species selected from the group of fava bean, soy, pea, chickpea, guar, potato, sunflower, lentil, rice, lupine, wheat, hemp and pumpkin.

[0061] A bonding composition of the invention usually has a pH in the range of 6.0-9.0, preferably in the range of 6.5-8.5 or in the range of 7.0-8.0.

[0062] A bonding composition of the invention may be present as a liquid or as a powder. Such powder may still have a few wt.% water in it, for example up to 2.0 wt.%, up to 4.0 wt.%, up to 7.0 wt.% or even up to 10 wt.%. The advantage of a powderous bonding composition is that it has a higher shelf life and is easier to handle or dose. Moreover, as compared to wet bonding compositions with higher wt.% of water, transport is more efficient and costs less energy.

[0063] A bonding composition of the invention may comprise further additives, such as plant fibers, salts, preservative agents and / or coloring agents.

[0064] When present, plant fibers are preferably present in an amount in the range of 0.50-5.0 wt.%.

[0065] The invention further relates to a method for coating a vegetarian or vegan foodstuff with a layer of gelled alginate, comprising the use of a bonding composition as described hereabove. Such method may comprise providing a bonding composition having a water content of lower than 60 wt.%, in particular providing a bonding composition that is substantially void of water; followed by diluting the composition with water to a water content that is in the range of 60-90 wt.%, in particular in the range of 65-85 wt.%.

[0066] The method of the invention preferably comprises - providing a vegetarian or vegan foodstuff comprising one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein;

[0067] - providing a bonding composition as described hereabove;

[0068] - providing an alginate solution in water;

[0069] - providing an aqueous solution of a divalent metal ion;

[0070] - applying to the foodstuff a layer of the bonding composition and a layer of the alginate solution, so that the layer of the bonding composition is positioned in between the foodstuff and the layer of the alginate; thereafter

[0071] - contacting the layer of the alginate solution with the aqueous solution of a divalent metal ion to yield the layer of gelled alginate; thereafter

[0072] - optionally heating the coated foodstuff to a temperature in the range of 40- 120 °C, in particular in the range of 60-100 °C, to generate an intermediate adhesive layer that binds the layer of gelled alginate to the foodstuff.

[0073] The heating step does not necessarily form part of the manufacturing process of the coated foodstuff. It may also be carried out by a consumer who prepares the foodstuff for consumption. To this end, a packaging of the foodstuff in which it is purchased and stored, typically instructs the consumer to heat the foodstuff, as a part of the general procedure that is to be carried out to prepare the foodstuff for consumption. A consumer may purchase the foodstuff at room temperature, in a cooled form (typically 0 - 10 °C) or in frozen form (typically -10 - -30 °C). Heating instructions to the consumer may entail keeping the foodstuff in a hot water bath or an oven for some time. In this way, the intermediate adhesive layer is generated in accordance with the invention, so that a foodstuff with a strongly bound coating is provided at the moment of its actual serving and consumption.

[0074] In an embodiment, the layer of the bonding composition and the layer of the alginate solution are provided sequentially.

[0075] In another embodiment, the foodstuff, the layer of the bonding composition and the layer of the alginate solution are coextruded by an extruder apparatus. This generally means that an elongated strand of food material leaves the die head of the extruder apparatus, and that such strand comprises a core of the foodstuff that is coated with an intermediate layer of the bonding composition and an outer layer of alginate solution. The strand is then contacted with the aqueous solution of a divalent metal ion, typically by pouring the solution over the strand or by dipping the strand into the solution, to provide the coating of gelled alginate. Thereafter, the extruded product may be heated to actually bind the coating to the foodstuff.

[0076] In a method of the invention, the protein in the bonding composition may be adapted to the protein in the foodstuff. For example, at least one type of protein that is present in the bonding composition corresponds to a type of protein that is also present in the foodstuff. This is typically performed by selecting a foodstuff and a bonding composition that both have at least one type of protein in common. For example, there is plant protein in the foodstuff and plant protein in the bonding composition; and / or there is fungal protein in the foodstuff and fungal protein in the bonding composition; and / or there is milk protein in the foodstuff and milk protein in the bonding composition; and / or there is egg protein in the foodstuff and egg protein in the bonding composition.

[0077] Preferably, the foodstuff and the bonding composition both comprise a protein that is derived from the same type of plant, for example from a type of plant selected from the group of legumes, vegetables, cereals, nuts and seeds. More preferably, the foodstuff and the bonding composition both comprise at least one and the same protein. This is typically performed by selecting a foodstuff and a bonding composition that both have at least one particular protein in common. For example, the protein that is present in the foodstuff as well as the bonding composition is a protein derived from a plant species selected from the group of fava bean, soy, pea, chickpea, guar, potato, sunflower, lentil, rice, lupine, wheat, hemp and pumpkin.

[0078] The presence of corresponding proteins may yield a stronger bond between the foodstuff and the bonding composition than when the proteins are different.

[0079] For the components of the bonding composition that is applied in the method of the invention, the same considerations apply as those elaborated hereabove for the bonding composition as such, such as the weight percentages of the components, the nature of the components and the substances that are mentioned to exemplary represent the components. The alginate solution in water that is used in a method of the invention usually has an alginate content in the range of 0.050-10 wt.% or 0.10-6.0 wt.%. Preferably, it is in the range of 0.20-4.0 wt.%, more preferably in the range of 0.50-3.0 wt.%.

[0080] The alginate used in a method of the invention is preferably sodium alginate. It is in principle also possible to use other alginates, such as potassium alginate or lithium alginate.

[0081] The weight average molar mass, Mw, of the dissolved alginate, in particular of dissolved sodium alginate, is usually in the range of 10.000-600.000 kg / mol. It may also be in the range of 30.000-300.000 kg / mol.

[0082] The aqueous solution of a divalent metal ion in a method of the invention typically has a total divalent metal ion concentration in the range of 1 .0- 5.0 mol / L, in particular in the range of 1 .3-4.0 mol / L. The divalent metal ion is preferably a calcium ion that is present as CaCh, i.e. the aqueous solution is a solution of CaCh in water. In such case, the concentration of CaCh is typically in the range of 15-45 wt.%.

[0083] The invention further relates to a vegetarian or vegan foodstuff obtainable by a method as described above.

[0084] The invention further relates to a vegetarian or vegan foodstuff comprising a gelled alginate coating, wherein

[0085] - the foodstuff comprises one or more proteins selected from the group of proteins derived from plants, proteins derived from fungus, proteins derived from milk and proteins derived from egg; and

[0086] - the coating adheres to the foodstuff.

[0087] In an embodiment, the vegetarian or vegan foodstuff comprises an intermediate adhesive layer that is positioned in between the foodstuff and the coating or casing, wherein there is

[0088] - a first bond between the intermediate adhesive layer and the foodstuff, the first bond relying on coagulated protein; and

[0089] - a second bond between the intermediate adhesive layer and the coating or casing, the second bond relying on the gelling of alginate.

[0090] The intermediate adhesive layer usually comprises the following components a) a gel of one or more hydrocolloid gelling agents, including at least alginate; b) one or more water binding agents comprising bound water, optionally comprising one or more of the same hydrocolloid gelling agents as in component a); c) one or more coagulated proteins selected from the group of plant protein, fungal protein, milk protein and egg protein.

[0091] On a dry matter basis, the intermediate adhesive layer usually comprises the following components a) 0.50-45 wt.% of one or more hydrocolloid gelling agents, including at least alginate; b) 1 .0-35 wt.% of one or more water binding agents; c) 20-90 wt.% of one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein; wherein alginate constitutes 0.25-80 wt.% of the dry matter of the intermediate adhesive layer.

[0092] It may also comprise these components in the following amounts a) 4.0-30 wt.%; b) 4.0-30 wt.%; c) 40-80 wt.%; wherein alginate constitutes 3.0-30 wt.% or 4.0-40 wt.% of the dry matter of the intermediate adhesive layer.

[0093] For the abovementioned components that are present in the intermediate adhesive layer, the same considerations apply as those elaborated hereabove for the bonding composition, on a dry matter basis, such as the weight percentages of the components, the nature of the components and the substances that are mentioned to exemplary represent the components.

[0094] In a foodstuff of the invention, there may be at least one type of protein that is present in the intermediate adhesive layer as well as the foodstuff. For example, there is plant protein in the foodstuff and plant protein in the bonding composition; and / or there is fungal protein in the foodstuff and fungal protein in the bonding composition; and / or there is milk protein in the foodstuff and milk protein in the bonding composition; and / or there is egg protein in the foodstuff and egg protein in the bonding composition. Preferably, the foodstuff and the intermediate adhesive layer both comprise a protein that is derived from the same type of plant, for example a plant selected from the group of legumes, vegetables, cereals, nuts and seeds. More preferably, the foodstuff and the intermediate adhesive layer both comprise at least one and the same protein, i.e. there is at least one protein that is present in the foodstuff as well as the intermediate adhesive layer. For example, the protein that is present in the foodstuff as well as the intermediate adhesive layer is a protein derived from a plant species selected from the group of fava bean, potato, soy, pea, chickpea, guar, sunflower, lentil, rice, lupine, wheat, hemp and pumpkin.

[0095] In an embodiment, the vegetarian or vegan foodstuff according to the invention is of an elongate shape having two opposite ends. It may in particular have the shape of a sausage. More in particular, a vegetarian or vegan foodstuff according to the invention is a vegan or vegetarian sausage.

[0096] With a bonding composition of the invention, alginate coatings can be provided on foodstuff that are resistant to high temperatures and that are not prone to delamination, also during heating the foodstuff, for example in water. The invention therefore opens the way to vegan and vegetarian food products, in particular sausages, with a non-animal derived coating that has properties comparable to those of a conventional animal-derived coating, in particular the property of adhesion to the foodstuff itself. This fulfills a long-felt need in the field.

[0097] It is further beneficial that any bonding composition according to the invention can be selected independently from the alginate coating in order to arrive at a foodstuff according to the invention, i.e. at a coated foodstuff having a strong bonding between the foodstuff and the coating. There are, for example, no components - except for the alginate - that need to be present in both the alginate coating and the bonding composition. This is an advantage, since other components in the coating may impair the quality of the coating.

[0098] As regards the foodstuff, the invention offers the advantage that the vegan or vegetarian foodstuff itself does not need to be modified in order to arrive at a good bonding. A particularly improved bonding, however, is obtained when the protein in the bonding composition corresponds in some way to the protein in the foodstuff. This may entail a similarity in type of protein (plant, fungus, milk or egg) or a similarity in the plant from which the plant protein is obtained. The best bonding is achieved when the foodstuff and the bonding composition actually comprise the same protein.

[0099] EXAMPLES

[0100] Example 1 : Vegan chicken filet with vegan chicken skin

[0101] A first coated vegan meat product was prepared according to the invention, wherein the foodstuff is a ‘vegan chicken dough’ and the alginate coating a ‘vegan chicken skin’.

[0102] The chicken dough is composed of water, rice texturate, wheat texturate, wheat gluten, soy isolate, methylcellulose, vegetable fibers, salt, aroma’s, herbs and spices. It is prepared by first blending the water and texturates, and then adding the other components. Mixing all components yields a firm and formable dough.

[0103] The chicken skin comprises water, sodium alginate, corn starch, vegetable fibers and aroma’s and is prepared by mixing these components.

[0104] The bonding composition according to the invention comprises alginate (2.8 wt.%), wheat fiber (4.7 wt.%), citrus fiber (1 .9 wt.%), soy isolate (4.4 wt.%), methylcellulose (1 .8 wt.%) and water (84.4 wt.%). On a dry matter basis, this corresponds to alginate (17.9 wt.%), wheat fiber (30,1 wt.%), citrus fiber (12.2 wt.%), soy isolate (28.2 wt.%), methylcellulose (11 .5 wt.%) and water (0.0 wt.%).

[0105] The preparation of the coated vegan chicken dough was performed by first forming the vegan chicken dough into ‘chicken filet shapes’. Then a layer of the bonding composition was applied to the filets, followed by a layer of the chicken skin ( / .e. the alginate). Thereafter, the coated filets were shortly submerged in a CaCh solution. Finally, the filets were placed in a steam oven for a few minutes to cause the coagulation of the proteins that are present in the bonding composition and the chicken dough. Figure 2 schematically displays a cross section of this product.

[0106] The coating of the resulting vegan chicken filets adhered well and in a continuous manner to the dough. No delamination and / or bursting of the coating was observed. Example 2: Vegan Frankfurter with alginate casing (I)

[0107] A second coated vegan meat product was prepared according to the invention, wherein the foodstuff is a ‘Frankfurter dough’ that is composed of water, oil, soy isolate, methylcellulose, starches, vegetable fibers, salt, aroma’s, herbs and spices. The dough is prepared in a bowl chopper. The oil and water are added and mixed into the dry components with high shear. The alginate comprises water, sodium alginate, guar gum, food acid and preservative agent. The bonding composition is the bonding composition as described in Example 1 .

[0108] The preparation of the coated foodstuff was performed by coextrusion of the Frankfurter dough, the bonding composition and the alginate. A special die head was used to get the vegan Frankfurter dough on the inside, the bonding composition around it and the alginate on the outside (triple co-extrusion). Each component was supplied by a separate pump. The extruded strand was passed through a CaCh solution and segmented to yield Frankfurter vegan sausages. Finally, the sausages were submerged in a 80 °C water bath for a few minutes to cause the coagulation of the proteins that are present in the bonding composition and the Frankfurter dough. Figure 1 schematically displays a cross section of this product.

[0109] The coating of the resulting Frankfurter vegan sausages adhered well and in a continuous manner to the dough (adhesion rating 3). No delamination and / or bursting of the coating was observed.

[0110] This Example is included in Table 1 , which displays the degree of adhesion of alginate casing to vegan Frankfurter dough for different bonding compositions (see also Examples 4 and 5). This experiment of Example 2 is labeled with Expt. No. 2 in Table 1.

[0111] Example 3: Method for evaluating the degree of adhesion of alginate

[0112] The following procedure was used to rate the adhesion of alginate casing to vegan sausage dough using different bonding compositions, so that the effect of different bonding compositions can be compared. Three evaluations were made sequentially. After the triple co-extrusion process, the vega(n) sausages were heated in water of 90 °C for 10 minutes. The sausages were evaluated on three different aspects, viz. 1 ) adhesion of alginate casing to the bonding composition during the heating process; 2) adhesion of alginate casing to the bonding composition after the heating process; and 3) adhesion of bonding composition to the inner vega(n) sausage dough. The overall adhesion was rated on a scale of 1 to 5, where 1 is very poor, 2 is poor, 3 is moderate, 4 is good and 5 is excellent. A value of 3 or higher was considered acceptable.

[0113] The first evaluation occurred during the heating process. In the event that the outer casing delaminated from the sausage (typically due to vaporized water originating from the bonding composition and / or the dough), then the bonding was classified as poor.

[0114] The second evaluation was performed on the identical sausages as evaluated during the first evaluation and was done by slicing that sausage over its entire length with a sharp knife and then attempting to remove the outer alginate casing by hand (in case this was not removed during the first evaluation). The degree of ease of removal, combined with the amount of bonding composition stuck to the outer casing, determined the adhesion between the bonding composition and the outer alginate casing. If the casing was easily removed with very little bonding composition remaining on the casing, this was evaluated as poor.

[0115] The third evaluation was done on the identical sausage as the second evaluation by attempting to peel the bonding composition from the inner dough by hand. If this was considered to be easy, it was classified as poor.

[0116] In case either the first or the second evaluation, and the third evaluation were both classified as poor, then the overall classification was very poor. In case only one of the evaluations was classified as poor, then the overall classification was also poor. In all other cases, the products were judged as moderate or higher.

[0117] Example 4: Vegan Frankfurter with alginate casing (II)

[0118] A variety of further coated vegan meat products were prepared according to the invention. The foodstuff to be coated was the ‘Frankfurter dough’ of Example 2; the method for doing so was the coextrusion method described in Example 2. Variations were made with respect to the bonding composition, viz. variations in the water binding agent and the protein. There are also variations in the (optional) additive, although the additive(s) here mainly serve(s) the purpose of obtaining a good color rather than a good adhesion (iron oxide for obtaining the optimal color for Frankfurter appearance and roasted wheat malt to color the intermediate adhesive layer to thereby facilitate analysis of its bonding characteristics by visual inspection).

[0119] The different bonding compositions and the results obtained therewith are displayed in Table 1 . Columns with components of the composition either list a particular component by name or indicate presence (“O”) or absence (“X”) of the compound listed in the column heading. The experiments of Example 4 are labeled with Expt. Nos. 4a, 4b, 4c, ..., 4r in Table 1 .

[0120] All of the obtained sausages display a good adhesion of the alginate to the Frankfurter dough (adhesion rating 3, 4 or 5). No delamination and / or bursting of the coating was observed.

[0121] Comparative Example 5: Vegan Frankfurter with alginate casing (III)

[0122] It was attempted to coat the vegan Frankfurter dough of Example 2 with alginate using comparative compositions that are not compositions according to invention. These compositions lack one or more of the components that are required by the bonding compositions of the invention, viz. the hydrocolloid, the alginate, the water binding agent and the protein. The method that was used for these attempts is the triple co-extrusion method described in Example 2. Each of the comparative compositions provides an insufficient adhesion of the alginate coating to the vegan Frankfurter dough (adhesion rating 1 or 2). These comparative experiments of Example 5 are labeled with Expt. Nos. 5a, 5b, 5c, ..., 5g in Table 1 .

[0123] Conclusion

[0124] The results of the above Examples demonstrate that it is possible with a range of bonding compositions according to the invention, to apply an alginate coating to vegan meat dough, wherein the coating has sufficient adhesion to the dough and is resistant to heating the coated product in water. Table 1. Coating results obtained with different bonding compositions of the invention

Claims

CLAIMS1 . Bonding composition for binding an alginate coating to a vegetarian or vegan foodstuff, comprising, on a dry matter basis, the following components a) 0.50-45 wt.% of one or more hydrocolloid gelling agents, including at least alginate; b) 1 .0-35 wt.% of one or more water binding agents; c) 20-90 wt.% of one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein; wherein alginate constitutes 0.25-80 wt.% of the dry matter of the bonding composition.

2. Bonding composition according to claim 1 , wherein the composition is in the form of a powder.

3. Bonding composition according to claim 1 or 2, wherein the one or more water binding agents is selected from the group of potato starch, corn starch, rice starch, wheat starch and tapioca starch.

4. Bonding composition according to any one of claims 1-3, wherein the one or more hydrocolloid gelling agents is selected from the group of cellulose, methyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, methyl ethyl cellulose and sodium carboxymethyl cellulose.

5. Bonding composition according to any one of claims 1-4, wherein the plant protein is derived from a species selected from the group of legumes, vegetables, cereals, nuts and seeds, in particular from a plant species selected from the group of fava bean, soy, pea, chickpea, guar, potato, sunflower, lentil, rice, lupine, wheat, hemp and pumpkin.

6. Bonding composition according to any one of claims 1-5, wherein the alginate constitutes 1 .0-40 wt.% of the dry matter of the bonding composition, in particular 2.0-20 wt.%, more in particular 3.0-10 wt.%.

7. Bonding composition according to any one of claims 1-6, wherein the water content of the bonding composition is in the range of 0.0-2.0 wt.%, in particular in the range of 0.0-0.20 wt.%.

8. Bonding composition according to any one of claims 1-7, wherein the water content of the bonding composition is in the range of 60-90 wt.%, in particular in the range of 65-85 wt.%.

9. Method for coating a vegetarian or vegan foodstuff with a layer of gelled alginate, comprising the use of a bonding composition according to any one of claims 1-8.

10. Method according to claim 9, comprising- providing a vegetarian or vegan foodstuff comprising one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein;- providing a bonding composition according to claim 8;- providing an alginate solution in water;- providing an aqueous solution of a divalent metal ion;- applying to the foodstuff a layer of the bonding composition and a layer of the alginate solution, so that the layer of the bonding composition is positioned in between the foodstuff and the layer of the alginate; then- contacting the layer of the alginate solution with the aqueous solution of a divalent metal ion to yield the layer of gelled alginate; then- optionally heating the coated foodstuff to a temperature in the range of 40- 120 °C, in particular in the range of 60-100 °C, to generate an intermediate adhesive layer that binds the layer of gelled alginate to the foodstuff.11 . Method according to claim 10, wherein the foodstuff, the layer of the bonding composition and the layer of alginate solution are coextruded by an extruder apparatus.

12. Method according to any one of claims 9-11 , wherein there is at least one protein that is present in the foodstuff as well as in the bonding composition,which protein is in particular a protein derived from a plant species selected from the group of fava bean, soy, pea, chickpea, guar, potato, sunflower, lentil, rice, lupine, wheat, hemp and pumpkin.

13. A vegetarian or vegan foodstuff comprising a gelled alginate coating, wherein- the foodstuff comprises one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein; and- the coating adheres to the foodstuff.

14. A vegetarian or vegan foodstuff according to claim 13, wherein the foodstuff comprises an intermediate adhesive layer that is positioned in between the foodstuff and the gelled alginate coating, wherein there is- a first bond between the intermediate adhesive layer and the foodstuff, the first bond relying on coagulated protein; and- a second bond between the intermediate adhesive layer and the coating, the second bond relying on the gelling of alginate.

15. A vegetarian or vegan foodstuff according to claim 14, wherein the intermediate adhesive layer comprises the following components a) a gel of one or more hydrocolloid gelling agents, including at least alginate; b) one or more water binding agents comprising bound water; c) one or more coagulated proteins selected from the group of plant protein, fungal protein, milk protein and egg protein.

16. A vegetarian or vegan foodstuff according to claim 14, wherein the intermediate adhesive layer comprises, on a dry matter basis, the following components a) 0.50-45 wt.% of one or more hydrocolloid gelling agents, including at least alginate; b) 1 .0-35 wt.% of one or more water binding agents; c) 20-90 wt.% of one or more proteins selected from the group of plant protein, fungal protein, milk protein and egg protein; wherein alginate constitutes 0.25-80 wt.% of the dry matter of the bonding composition.A vegetarian or vegan foodstuff according to any one of claims 13-15, wherein there is at least one protein that is present in the foodstuff as well as in the intermediate adhesive layer, which protein is in particular a protein derived from a plant species selected from the group of fava bean, soy, pea, chickpea, guar, potato, sunflower, lentil, rice, lupine, wheat, hemp and pumpkin. A vegetarian or vegan foodstuff according to any one of claims 13-16, wherein the foodstuff is of an elongated shape having two opposite ends, in particular wherein the foodstuff is a vegan or vegetarian sausage. A vegetarian or vegan foodstuff obtainable by a method according to any one of claims 9-12.

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