Field of the invention

The present invention relates to a food product comprising multimineral iron-containing particles.

Background of the invention

Iron deficiency is the most common and widespread nutritional disorder in the world and is a public health problem in almost all countries. Iron deficiency is the result of a longterm negative iron balance; in its more severe stages, iron deficiency causes anaemia. Anaemia is defined as a low blood haemoglobin concentration. Haemoglobin cut-off values that indicate anaemia vary with physiological status (e.g. age, sex) and have been defined for various population groups by WHO.

Iron fortification of food is a methodology utilised worldwide to address iron deficiency.

Technically, iron is the most challenging micronutrient to add to foods, because the iron compounds that have the best bioavailability tend to be those that interact most strongly with food constituents to produce undesirable organoleptic changes. When selecting a suitable iron compound as a food fortificant, the overall objective is to find the one that has the greatest absorbability, yet at the same time does not cause unacceptable changes to the sensory properties (i.e. taste, colour, texture) of the food vehicle.

A wide variety of iron compounds are currently used as food fortificants. These can be broadly divided into three categories:

• water soluble;

• poorly water soluble but soluble in dilute acid;

• water insoluble and poorly soluble in dilute acid.

Being highly soluble in gastric juices, the water-soluble iron compounds have the highest relative bioavailability of all iron fortificants. However, water soluble iron compounds are also the most likely to have adverse effects on the organoleptic qualities of foods, in particular, on the colour and flavour. Unwanted colour changes typically include a green or bluish colouration in cereals, a greying of chocolate and cocoa, and darkening of salt to yellow or red/brown. During prolonged storage, the presence of fortificant iron in oil containing foods can cause rancidity and subsequent off flavours. Ferrous sulfate is the most frequently used water-soluble iron fortificant. Other water- soluble iron compounds that have been used for iron fortification are ferrous gluconate, ferrous lactate, ferrous bisglycinate, ferric ammonium citrate and sodium iron EDTA.

Ferrous sulfate and ferrous fumarate are available commercially in encapsulated form and are currently used in dry infant formulas and in infant cereals, predominantly in industrialised countries. The main purpose of encapsulation is to separate the iron from the other food components, thereby mitigating sensory changes. When developing encapsulated iron fortificants, it is important to select a coating that provides an adequate balance between stability and bioavailability. Iron compounds are usually encapsulated with hydrogenated vegetable oils, but mono- and diglycerides and ethyl cellulose, have also been used.

Even in relatively dry foodstuffs such as savoury concentrates, the presence of iron can cause undesirable changes in the organoleptic properties, including appearance and/or negatively influence storage stability. Thus previous strategies have been devised to effectively fortify food products.

WO 2010/086192 A (Unilever PLC et al) discloses a dry savoury food concentrate comprising: a) from 30 percent wt. to 70 percent wt. of NaCI; b) from 0.05 percent wt. to 2 percent wt of an iron ion selected from the group consisting of Fe ²⁺ and Fe ³⁺ and mixtures thereof, which iron ion is derived from an added iron compound which is dissolvable in an aqueous solution, c) from 0.35 percent wt. to 7.0 percent wt of an acid compound selected from the group consisting of citric acid, ascorbic acid, malic acid, tartaric acid, lactic acid and mixtures thereof, all weight percent based on the weight of the total dry savoury food concentrate, and wherein the ratio of acid ions to iron ions on molecular level is between 1 :1 and 10:1 , and wherein the concentrate is a concentrate selected from the group of concentrates consisting of a bouillon concentrate, a soup concentrate, a sauce concentrate and a gravy concentrate

WO 2014/135387 A (Unilever PLC et al) discloses a savoury food concentrate comprising sodium chloride, glutamate, an iron salt, and further non-iron phosphate salt. WO 2017/108351 A (Unilever PLC et al) discloses a savoury concentrate containing: • 30-80 weight percent of salt particles, including at least 0.002 weight percent of iron- containing salt particles comprising: 0.03-30 mole percent of iron cation selected from Fe ²⁺ , Fe ³⁺ and combinations thereof; 10-49.97 mole percent of non-iron cations selected from Na ⁺ , K ⁺ , Ca ²⁺ , NH ⁴⁺ and combinations thereof; 16-70.2 mole percent of Cl'; 0-30 mole percent of anions selected from SC ² ', citrate, fumarate and combinations thereof; • at least 3 weight percent of taste imparting components selected from glutamate, sugars, pieces of plant material and combinations thereof; • 0-30 weight percent of oil; and • 0-10 weight percent water.

The present inventors have recognised a need for a new vehicle for iron-fortification of foodstuffs which can be readily synthesised, ameliorate problems with stability and/or afford good bioavailability.

Summary of the invention

The present invention provides a food product comprising multimineral iron-containing particles of general formula M1 _w M2 _x M3yM4 _z L1aL2bL3 _c L4d, wherein

• M1 is Fe ²⁺ ,

• M2 is Fe ³⁺ ,

• M3 is selected from Na ⁺ , K ⁺ , NH ₄ ⁺ and combinations thereof,

• M4 is selected from Ca ²⁺ , Mg ²⁺ , Mn ²⁺ , Zn ²⁺ and combinations thereof,

• L1 is selected from OH; HCOT, H2PO4; H3P2O?' and combinations thereof,

• L2 is selected from CO3 ² ; HPO4 ² ; H2P2O? ² ' and combinations thereof,

• L3 is selected from PO4 ³ ; HP2O? ³ ' and combinations thereof,

• L4 is P ₂ O ₇ ⁴ ',

• 2w + 3x + y + 2z = a + 2b + 3c + 4d,

• each of w, x, y, a, b, c and d are > 0,

• z > 0,

• w + x > 0, and

• [(w + x) / (w + x + y + z)] < 0.50.

The particles for use in the present invention are multimineral in that each particle contains multiple cations. As can be seen from the chemical formula for the particles, each particle in the multimineral salt contains at least some iron cations (i.e. , w + x > 0) and at least some calcium, magnesium, manganese, and/or zinc cations (i.e. , z > 0). As the general formula is a conventional chemical formula, the subscripts a, b, c, d, w, x, y and z represent the molar proportion of each ion in the salt that forms the particles.

Multimineral particles for use in the present invention comprise anions selected from hydroxide, carbonate, phosphate and/or pyrophosphate anions. The use of the specified anions provides that the particles have low water solubility except when they reach the very low pH environment of the gastric juices. The present inventors have found however, that if the iron content of the particles is above a certain level then only limited solubility at the very low pH environment of the gastric juices is achieved. Thus the mole fraction of iron in the cations (i.e., [(w + x) / (w + x + y + z)]) of the particles is less than 0.50 to achieve good solubility at low pH.

Detailed description

The present invention provides a food product comprising multimineral iron-containing particles of general formula M1 _w M2 _x M3yM4 _z L1aL2bL3 _c L4d, wherein

• M1 is Fe ²⁺ ,

• M2 is Fe ³⁺ ,

• M3 is selected from Na ⁺ , K ⁺ , NH4 ⁺ and combinations thereof,

• M4 is selected from Ca ²⁺ , Mg ²⁺ , Mn ²⁺ , Zn ²⁺ and combinations thereof,

• L1 is selected from OH; HCOT, H2PO4; H3P2O and combinations thereof,

• L2 is selected from CO3 ² ; HPO4 ² ; H2P2O? ² ' and combinations thereof,

• L3 is selected from PO4 ³ ; HP2O? ³ ' and combinations thereof,

• L4 is P2O7 ⁴ ;

• 2w + 3x + y + 2z = a + 2b + 3c + 4d,

• each of w, x, y, a, b, c and d are > 0,

• z > 0,

• w + x > 0, and

• [(w + x) / (w + x + y + z)] < 0.50.

The present inventors have found that by keeping the mole fraction of iron in the cations of the particles ([(w + x) / (w + x + y + z)]) below 0.50, the particles have low solubility at pH values typical of food products but good solubility at the very acidic pH of gastric juices. In terms of solubility at gastric pH, this is reflected by the solubility of the iron in the particles at pH 2.0. This can conveniently be determined by the methods given in Example 1 and, in particular, by measuring the amount of iron solubilised in a 10 mg/ml dispersion of the particles in deionised water titrated with 0.1 M HCI and incubated at 23 °C for 2 hours. It is preferred that at least 3% by weight of the iron (M1 + M2) in the particles is soluble in water at pH 2.0 and 23 °C, more preferably at least 5%, more preferably still at least 10% and most preferably from 15 to 100%.

In terms of stability in typical food products, this is reflected by the solubility of the iron in the particles at pH 6.0. This can conveniently be determined by the methods given in Example 1 and, in particular, by measuring the amount of iron solubilised in a 10 mg/ml dispersion of the particles in deionised water titrated with 0.1 M HCI and incubated at 23 °C for 2 hours. It is preferred that less than 3% by weight of the iron (M1 + M2) in the particles is soluble in water at pH 6.0 and 23 °C, more preferably less than 2%, more preferably still less than 1 %, even more preferably less than 0.5% and most preferably from 0 to 0.2%.

The pH-dependent solubility of the particles between pH 2 and 6 may become more pronounced at lower iron contents. Thus it is preferred that the mole fraction of iron in the cations of the particles ([(w + x) / (w + x + y + z)]) is no more than 0.40, more preferably no more than 0.35, more preferably still no more than 0.30 and most preferably no more than 0.28.

The iron content of the particles is preferably not too low, otherwise excessive amounts may be needed to be added to the food product. In addition, the present inventors have found that it is difficult to produce homogenous, small multimineral particles where the iron content is low. Therefore it is preferred that the mole fraction of iron in the cations of the particles is at least 0.04, more preferably at least 0.05, more preferably still at least 0.06, even more preferably at least 0.08 and most preferably at least 0.10.

The particles preferably comprise the non-iron divalent cations M4 in a substantial amount to ensure low water solubility and preferably one or more additional advantages such as improved colour, bioavailability and/or ease of dosing due to bulking out of the iron. Thus it is preferred that the particles comprise at least 20 mol% of M4, more preferably at least 30 mol%, more preferably still at least 35% and most preferably from 40 to 60 mol%. The mol% of M4 is calculated by dividing z by the sum of w, x, y, z, a, b, c and d ( i.e. = 100 z / (w + x + y + z + a + b + c + d)).

Although the non-iron divalent cation M4 may comprise or be Zn ²⁺ , it is most preferred that it is selected from Ca ²⁺ , Mg ²⁺ , Mn ²⁺ and combinations thereof, more preferably selected from Ca ²⁺ , Mg ²⁺ and combinations thereof due the low recommended daily intake of Zn ²⁺ and Mn ²⁺ compared with Ca ²⁺ and Mg ²⁺ . Preferably the particles comprise less than 35 mol% of Zn ²⁺ , more preferably less than 10 mol %, more preferably still less than 5 mol%, even more preferably less than 1 mol% and most preferably from 0 to 0.1 mol%.

The monovalent cations M3 are optionally present in the particles but where present it is preferred they only make up a small proportion of the ions in the particles to avoid the particles becoming too water soluble. Thus it is preferred that the particles comprise less than 10 mol% of M3, more preferably less than 5 mol%, and more preferably still less than 1 mol% and most preferably from 0.001 mol% to 0.1 mol%. In a preferred embodiment the particles are essentially free from M3 cations.

The hydroxyl anion (OH-) is optionally present in the particles but where present it is preferred it only makes up a small proportion of the ions in the particles and that the majority of the anions (mol%) are carbonate, phosphate and/or pyrophosphate anions. Thus it is preferred that the particles comprise less than 10 mol% of OH; more preferably less than 5 mol%, and more preferably still less than 1 mol% and most preferably from 0.001 mol% to 0.1 mol%. In a preferred embodiment the particles are essentially free from OH'.

The preferred anions are phosphates and pyrophosphates and so preferably the anions comprise phosphate and pyrophosphate in a total amount of at least 50 mol% of the anions, more preferably at least 70 mol% and most preferably from 90 to 100 mol% of the anions. By mol% of the anions means 100 times the amount of phosphates and pyrophosphates divided by the sum of a, b, c and d. The most preferred anion is pyrophosphate (P2O? ⁴ ') and so preferably the anions comprise pyrophosphate in an amount of at least 50 mol% of the anions, more preferably at least 70 mol% and most preferably from 90 to 100 mol%.

In a preferred embodiment the formula of the particles is Ca2(i-j)Fe4j(P2O7)(i+2j), wheren j is in the range of from 0.04 to 0.32. More preferably j is in the range of from 0.05 to 0.30, even more preferably in the range of from 0.08 to 0.25, even more preferably still in the range of from 0.09 to 0.20 and most preferably in the range of from 0.10 to 0.17.

Some examples of the formulae of particles for use in the invention and the corresponding values of w, x, y, z, a, b, c and d, as well as the amount of iron in the cations of the particles (mol fraction) are given in Table 1.

TABLE 1

As used herein, the term “food product” means foodstuffs for human consumption (including but not limited to spreads, dressings, seasonings, bouillons, soups, sauces, frozen foods, dairy products, confectionery, ice cream, side dishes, premixes intended to be frozen and consumed as ice cream or frozen confectionery), and beverages (including drinks, tea), that are ingested and assimilated to produce energy, stimulate growth, and/or maintain life. This definition also includes edible unit dose formats, ready to use meals, meal solutions, including any precursors (including concentrates) and components for the same. The food product preferably has a pH at 23°C of at least 3.0 to prevent that the iron in the particles is excessively soluble in the food product. More preferably the pH of the food product is from 3.5 to 9.0, more preferably still 4.0 to 8.0, even more preferably 4.5 to 7.5 and most preferably from 5.0 to 7.0.

Preferred forms of the food product are tea beverages, cereal-based beverages, dressings, frozen confections, and savoury products.

As used herein “tea beverages” means beverages that contain tea and/or herbal infusions, and precursors for the same including tea and/or herbs in infusion packages (such as tea bags), loose leaf tea and tea-based powders such as milk tea powders. The term “tea” refers to material from the leaves and/or stem of Camellia sinensis var. sinensis and/or Camellia sinensis var. assamica.

As used herein, “cereal-based beverages” means beverages that contain cereal material and precursors for the same including powders. By “cereal material” is meant material derived from a cereal plant, especially a cereal plant selected from one or more of wheat, barley, rye, maize, rice, sorghum, millet and oats.

As used herein the term “dressings” means food products for serving with other meal components or for mixing with salad, and includes mayonnaise and light mayonnaise at all fat levels, cold sauces, ketchup, mustard, salad dressings, and vinaigrettes.

As used herein “frozen confections” means food products that are generally served for consumption in frozen form, and that usually contain water and sugar, and may contain dairy ingredients, oils and/or fats, fruit, fruit juice, fruit extracts, flavours, and other ingredients like nuts and chocolate; and includes ice cream, frozen dairy desserts, sorbets, water-ices, slushes, frozen drinks, non-dairy ice cream analogues, premixes, intermediaries and final products associated with the same. The term also encompasses composite frozen confections that include components for such as chocolate, and wafers.

As used herein “savoury products” means food products that generally contain table salt at a level of at least 0.5 wt% in a prepared product or are formulated to provide an equivalent salty taste, and include bouillons, seasonings, meal makers, hot and cold soups, sauces, gravies, meals and sides, cooking aids and concentrates (such as cubes or powders) for preparing any of the foregoing.

As used herein “concentrate” refers to a dry composition (i.e. comprising no more than 20% water by weight of the concentrate) that can be used in the preparation of a foodstuff, or can be added to meal components as a seasoning.

The food product of the present invention may be a savoury concentrate and can suitably be used in the preparation of e.g. sauces, soups, gravies etc., or it can be added to meal components as a seasoning. Sauces and seasonings have several advantages as vehicles for iron fortification. They are traditionally part of the daily diet in most countries, widely consumed, reach vulnerable populations, and can be added to all kinds of foods.

The food product of the present invention may be a beverage precursor, suitable for combination with water, milk or other edible liquid to prepare a beverage.

The food product of the present invention offers the advantage that the iron contained therein is readily ingestible and preferably highly bioavailable. Furthermore, at least in some embodiments, the iron-containing salt particles contained in the food product do not give rise to unacceptable colour changes. An additional or alternative advantage of the present invention is that, as the particles are multi-mineral, the food product can be used as a vehicle not only for iron fortification but also fortification with other minerals such as, for example, calcium, zinc and the like.

The amount of the multimineral iron-containing particles in the food product will vary depending on the amount of iron in the particles, the size of a single serving of the food product and the recommended daily allowance of iron for the person consuming the food product. One unit of the food product typically contains at least 0.01 mmol, more preferably from 0.02 to 0.2 mmol and most preferably 0.025 to 0.1 mmol of iron. Here the term “unit” refers to the amount of food product that is provided in a single packaging unit and/or serving. In case multiple packaging units are packaged together (e.g. a plurality of wrapped bouillon blocks in a single box), the term “unit” refers to the amount of food product contained in the smallest packaging unit. Preferably, the food product comprises the multimineral iron-containing particles in an amount of at least 0.002% by weight of the food product, more preferably at least 0.005% by weight, most preferably from 0.01 % to 2% by weight.

Where the food product is a concentrate, the concentrate preferably comprises from 0.01 to 70% of the multimineral iron-containing particles by weight of the concentrate, more preferably from 0.05 to 20% and most preferably from 0.1 to 5%.

The multimineral iron-containing salt particles in the concentrate typically have a mass- weighted average diameter in the range of 0.1 to 5,000 pm, more preferably 1 to 1 ,000 pm and most preferably of 3 to 300 pm. Particle size and particle size distribution measurement can be suitably done by using light scattering methods, such as static light scattering (e.g. using Mastersizer™ by Malvern Panalytica), dynamic light scattering (e.g. Zetasizer Nano™ by Malvern Panalytica), and/or microscopy based methods such scanning electron microscopy (e.g. Merlin™ by Carl Zeiss) or transmission electron microscopy (e.g. TECNAI-20™ by Philips), or a combination thereof if the particle size is very polydisperse.

The multimineral iron-containing salt particles are preferably prepared by a method involving wet chemical precipitation, also known as co-preci pitation. Co-precipitation is a well-established process to produce various mixed organic and inorganic composite particles (see, for example, van Leeuwen, et al. RSC Adv., 2012, 2, 2534-2540, the disclosure of which is hereby incorporated by reference in its entirety). Preferably two or more soluble metal salts wherein at least one comprises M1 and/or M2 and at least one other comprises M4, are dissolved together in water and mixed with an aqueous solution of a salt comprising L1 , L2, L3 and/or L4. Upon mixing, a chemical reaction take place leading to a precipitation of the iron-containing multimineral particles. Optionally, the particles can be separated from the mixture and purified, for example by washing with water.

In one embodiment, the particles may be made from the soluble metal salts and the anion-containing salt by mixing them at very low or very high pH, and then adjusting the pH by addition of strong base or strong acid to a pH at which the multimineral iron- containing particles precipitate. Additionally, or alternatively, the precipitation can be done using inverted emulsion or microemulsion methods. Additionally, or alternatively, the precipitation can be conducting under shear or/and sonication. Additionally, or alternatively, the precipitation can be done in the presence of a stabilising polymer as described, for example, in WO 2007/009536 A, the disclosure of which is hereby incorporated by reference in its entirety.

The composition of the precipitated particles can be determined by using conventional methods for elemental analysis such as X-ray fluorescence (XRF), atomic absorption spectroscopy (AAS), and/or inductively coupled plasma (ICP) techniques: ICP-optical emission spectroscopy (ICP-OES), ICP-mass spectrometry (ICP-MS), Energy- Dispersive X-ray spectroscopy (EDXS), or combination of them. For compositional analysis the particles have to be separated from the reaction mixture and washed with water, or other solvent suitable for selectively solubilising the unreacted salts, to remove any unreacted soluble salts. EDXS is preferably used to determine the composition of the particles.

The food product typically comprises taste-imparting components. Taste-imparting components are preferably selected from amino acids, sugars, pieces of plant material and combinations thereof. Where the food product is a concentrate, the taste-imparting components are preferably contained in the concentrate in a concentration of at least 3% by weight of the concentrate, preferably 5% by weight of the concentrate, more preferably in a concentration of at least 10% and most preferably in a concentration of from 12 to 50%.

According to a particularly preferred embodiment, and especially where the concentrate is a savoury concentrate, the concentrate comprises at least 0.5% amino acids by weight of the concentrate. More preferably, the concentrate comprises from 1 to 35% amino acids, most preferably 5 to 30% amino acids. The amino acids can be selected from one or more taste-imparting amino acid or salt thereof. Particularly preferred are one or more amino acids selected from alanine, aspartate, glutamate, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, theanine, tyrosine, tryptophan, and valine. Especially preferred is glutamate owing to its ability to impart a umami taste. The pieces of plant material are preferably in the form of leaves, slices, florets, dices or other pieces. The concentrate preferably comprises 0 to 30%, more preferably 0.1 to 20% and even more preferably 1 to 10% by weight of the concentrate of the pieces of plant material. Preferably the pieces are pieces of plants selected from vegetables, herbs, spices and combinations thereof. Examples of sources of plant material include parsley, dill, basil, chamomile, chives, sage, rosemary, thyme, oregano, ginger, leek, garlic, onion, mushrooms, broccoli, cauliflower, tea, tomato, courgette, asparagus, bell pepper, egg plant, cucumber, carrot and coconut flesh. Where the concentrate is a beverage precursor, the plant material may be tea material. Where the concentrate is a beverage precursor comprising tea material, the concentrate preferably comprises at least 50% tea material by weight of the concentrate, more preferably at least 70% and most preferably from 90 to 99%.

The sugars that can be used as taste-imparting component are preferably selected from monosaccharides, disaccharides and combinations thereof. More preferably the sugars are selected from sucrose, glucose, fructose, maltose, lactose and mixtures thereof. More preferably still the sugars are selected from sucrose, glucose, fructose and mixtures thereof. Most preferably the sugars comprise sucrose. The sugars may be included in the concentrate in substantially refined form and/or may be present as part of more complex ingredients of the concentrate such as, for example, cereal materials, maltodextrins, glucose syrups, milk powders and the like.

Preferably the concentrate comprises the sugars in an amount of from 1 to 50% by weight of the concentrate, more preferably from 2 to 40%, more preferably still from 3 to 30% and most preferably from 4 to 20%.

The term “fat” as used herein refers to fatty acid glycerol ester selected from triglycerides, diglycerides, monoglycerides, phosphoglycerides and combinations thereof.

The concentrate of the present invention preferably contains at least 1% fat by weight of the concentrate. More preferably, the concentrate contains 3 to 40% fat, most preferably 5 to 35% fat. The fat contained in the concentrate may be liquid, semi solid or solid. Preferably, the fat contained in food concentrate has a solid fat content at 20°C (N20) of from 0 to 95%. Even more preferably, the fat has a N20 of at least 10% and most preferably the fat has a N20 of 25 to 90%. The solid fat content of the fat can suitably be determined using the method described in Animal and vegetable fats and oils -- Determination of solid fat content by pulsed NMR -- Part 1 : Direct method - ISO 8292- 1 :2008.

Preferably the fat comprises palm oil, palm kernel oil, fractionated palm oil, palm oil stearin, fully hydrogenated palm oil, shea oil, shea butter, shea oil stearin, coconut fat, cacao butter, tallow, chicken fat, butter fat, sunflower oil, rapeseed oil, soybean oil, linseed oil, olive oil or combinations of two or more thereof.

The concentrate of the present invention preferably comprises at least 1 % polysaccharide by weight of the concentrate. More preferably, the concentrate contains 3 to 60% polysaccharide, most preferably 5 to 50% polysaccharide The polysaccharide may be a substantially refined polysaccharide such as a gum (e.g. guar gum, locust bean gum, xanthan gum, tara gum, gelan and mixtures thereof) and/or starch. Additionally or alternatively the polysaccharide may be part of a complex ingredient of the concentrate such as, for example, flour.

The concentrates of the present invention are dry, wherein “dry” means that they comprise no more than 20% water by weight of the concentrate. The water content of the concentrate preferably does not exceed 10% by weight of the concentrate, more preferably does not exceed 8% and even more preferably the water content is from 0.01 to 6% by weight of the concentrate.

The water activity (at 20 °C) of the concentrate is preferably in the range of 0.1 to 0.6. More preferably, the water activity is in the range of 0.15 to 0.4, most preferably in the range of 0.1 to 0.2.

The water content of the concentrate and of salt particles, including the iron-containing salt particles, unless indicated otherwise, is determined by oven drying, e.g. using an Ecocell™ drying oven without the continuous air function at 90 °C (3 days). It should be understood that the multimineral salt particles for use in the present invention may contain small amounts of water (e.g. water of crystallisation) but where referring to any concentration or amount of a component of the particles, this is of the dry content of the particles. In contrast for the concentrate, amounts are by total weight of the concentrate (unless specified otherwise) including any water therein.

The concentrate preferably comprises a table salt in addition to the multimineral iron- containing salt particles. By “table salt” is meant salt comprising NaCI, KCI and mixtures thereof, most preferred is NaCI. Preferably, the amount of table salt in the concentrate is at least 3% by weight of the concentrate, more preferably at least 5%, even more preferably at least 8%, still more preferably at least 10%, yet more preferably at least 15%, and even still more preferably at least 20%. Preferably, the amount of table salt is at most 70% by weight of the concentrate, more preferably at most 60%, even more preferably at most 50%, and still more preferably at most 40%. Preferably, the amount of NaCI in the savoury concentrate is at least 3% by weight of the concentrate, more preferably at least 5%, even more preferably at least 10%, still more preferably at least 15% and preferably at most 60%, more preferably at most 55%, and still more preferably at most 50%.

Where the concentrate is a savoury concentrate, the polysaccharide in the concentrate preferably comprise a starch component selected from native (ungelatinised) starch, pregelatinised starch, maltodextrin, modified starch and combinations thereof. The starch component is preferably present in the savoury concentrate in a concentration of 3 to 50% by weight of the concentrate, more preferably of 4 to 30% and most preferably of 5 to 25%. The starch component is preferably selected from native starch, maltodextrin, pregelatinised starch and combinations thereof. Even more preferably, the starch is selected from native starch, pregelatinised starch and combinations thereof. Most preferably, the starch component is native starch. The starch component typically has a mass weighted mean diameter in the range of 5-200 pm, more preferably of 10- 100 pm, most preferably of 12-60 pm.

In a preferred embodiment, the savoury concentrate comprises:

- 5 to 30% fat by weight of the concentrate; and

- 35 to 75% of total inorganic salt by weight of the concentrate, wherein the total inorganic salt comprises the multimineral iron-containing particles. The inorganic salt preferably comprises, consists essentially of or consists of a mixture of table salt and the multimineral iron-containing particles. Preferably the inorganic salt comprises table salt in an amount of at least 50% by weight of the inorganic salt, more preferably at least 70%, more preferably still at least 85%, even more preferably at least 90% and most preferably from 95 to 99%.

In an alternative embodiment, the savoury concentrate may be formulated to provide a savoury taste without containing substantial amounts of table salt. Thus in a preferred embodiment the savoury concentrate comprises:

- 10 to 35% fat by weight of the concentrate;

- 10 to 50% ungelatinised starch by weight of the concentrate;

- 10 to 50% by weight of the concentrate of an oligosaccharide-containing material selected from dry glucose syrup, maltodextrin and combinations thereof.

In some embodiments the concentrate may be a beverage precursor. Preferred are teabeverage precursors or cereal-based beverage precursors. Particularly preferred are precursors of cereal-based beverages as cereal-based beverages have good opacity and strong flavour that forms a robust base for masking any organoleptic effects of the multimineral particles. The preferred beverage precursors comprise 20 to 80% cereal material by weight of the concentrate. The material may be flour, starch, extract or a mixture thereof. In a preferred embodiment, at least part of the cereal material is malted. Especially preferred is malted wheat, barley ora mixture thereof. Cereal material typically contributes a significant amount of polysaccharide to the concentrate and so the beverage precursor may contain at least 10% polysaccharide by weight of the concentrate, preferably at least 20% and most preferably 30 to 60% polysaccharide by weight of the concentrate.

Generally the concentrate can come in several forms or shapes: typical forms are free- flowing powders, granulates, shaped concentrates and pastes.

According to a particularly preferred embodiment the concentrate of the present invention is a shaped article, notably a shaped solid article. Examples of shaped solid articles include concentrates in the form of cubes, tablets or granules. The shaped article preferably has a mass in the range of 1 to 50 g, more preferably in the range of 2.5 to 30 g and most preferably of 3.2 to 24 g. The shaped concentrate article can suitably be provided in different forms. Preferably, the article is provided in the form of a cuboid, more preferably in the form of a rectangular cuboid and most preferably in the form of a cube.

The concentrate of the present invention preferably is a packaged concentrate. Where the concentrate is a savoury concentrate in the form of a shaped article, it is preferred that the article is packaged in a wrapper.

Another aspect of the invention relates to a process for manufacturing the concentrate. The process comprises the steps of:

(i) preparing a mixture comprising the multimineral iron-containing particles and the taste-imparting components; and

(ii) packaging the mixture.

Especially for savoury concentrates, the process preferably includes the addition of fat to the mixture in step (i). Other components that may suitably be added during step (i) include thickening agents, colouring and combinations thereof.

Especially for beverage precursors, the process preferably includes the addition of cereal material to the mixture in step (i). Other components that may suitably be added during step (i) include protein isolates, milk solids, cocoa powder, flavourings, food acids, colours, anti-caking agents, vitamins and combinations thereof.

Preferably the mixture is shaped prior to packaging. The concentrate is preferably shaped by allowing the concentrate to solidify in a mould or by pressing the concentrate into a predefined shape (e.g. by extrusion or tabletting). The shaping preferably comprises a technique selected from the group consisting of compression, extrusion, roller compacting, granulation, agglomeration and combinations thereof.

The invention also relates to a method for preparing a food product comprising dissolving and/or dispersing the food concentrate in an aqueous medium. Where the concentrate is a savoury concentrate, the food product is a bouillon, a soup, a sauce, a gravy or a seasoned dish. Where the concentrate is a beverage precursor, the food product is a beverage. Typically the aqueous medium will be hot (greater than 60 °C) water but in some instances may be a semi-finished dish comprising water and other ingredients, or may be another aqueous liquid such as milk.

The food concentrate is preferably dissolved and/or dispersed in the aqueous medium in a weight ratio of concentrate to aqueous medium of from 1 :2000 to 1 :4, more preferably from 1 :1000 to 1 :5 and most preferably 1 :500 to 1 :7.

As used herein the term “comprising” encompasses the terms “consisting essentially of” and “consisting of”. Where the term “comprising” is used, the listed steps or options need not be exhaustive. Except in the examples and comparative experiments, or where otherwise explicitly indicated, all numbers are to be understood as modified by the word “about”. As used herein, the indefinite article “a” or “an” and its corresponding definite article “the” means at least one, or one or more, unless specified otherwise.

Unless otherwise specified, numerical ranges expressed in the format "from x to y" are understood to include x and y. In specifying any range of values or amounts, any particular upper value or amount can be associated with any particular lower value or amount. All percentages and ratios contained herein are calculated by weight unless otherwise indicated.

The various features of the present invention referred to in individual sections above apply, as appropriate, to other sections mutatis mutandis. Consequently features specified for the food product may be combined with features specified for the process and vice versa.

The following examples are intended to illustrate the invention and are not intended to limit the invention to those examples perse.

Examples

All materials used in the Examples are obtained from commercial sources in the Netherlands. Example 1

This example demonstrates preparation and properties of multimineral iron-containing particles and their properties.

Materials

Ferric chloride hexahydrate (FeC -QFW, >99%), tetrasodium pyrophosphate decahydrate (Na4P20y10H20, >99%) and calcium dichloride (CaCh, > 93%) were obtained from Sigma Aldrich. Milli-Q (MQ) water was deionised by a Millipore Synergy water purification system.

Centrifugation force

Where the centrifugation force is given, it is given as a dimensional “relative centrifugal force", which is defined as r a> ² /g, where g = 9.8 m/s ² is the Earth's gravitational acceleration, r is the rotational radius of the centrifuge, o) is the angular velocity in radians per unit time. The angular velocity is = rpm x 2n / 60, where rpm is the centrifuge “revolutions per minute”.

Preparation of Fe4(P2O?)3 and Ca2P2O? particles

Iron (III) pyrophosphate (Fe4(P2O?)3) and calcium pyrophosphate (Ca2P2O?) were separately prepared by dissolving 0.857 and 1.286 mmol of FeC -SFW and CaCh in 50 ml MQ water, respectively. Each of these solutions were added quickly to a solution of 0.643 mmol Na4P20y10H20 in 100 ml MQ water while stirring vigorously by a magnetic stir bar. A turbid white dispersion formed during addition after a couple of seconds. The samples were then centrifuged at 3273 g for 15 minutes in 50 ml volume polypropylene (PP) conical centrifuge tubes using an Allegro X-12R Centrifuge followed by washing the precipitate twice with MQ water. The sediment was dispersed by sonication (10 minutes) using a Branson Ultrasonics™ CPXH series ultrasonic cleaning bath, CPX8800H model, after which they were dried in an oven at 45°C overnight.

Preparation of Ca2(i-j)Fe4j(P2O7)(i+2j) particles

Mixed iron and calcium salts were prepared at fixed concentration of pyrophosphate ions (6.43 mM) and by substituting part of the calcium content in the precursor Ca2P2O? solution by iron. Nine different samples containing low to high Fe content with substitution of Fe in Ca2P2O?, generally coded as Ca2(i-j)Fe4j(P2O7)(i+2j) (0<j<1), for different target j values as given in Table 2. For the target j value, a minimum and a maximum of 0.005 and 0.26 was chosen, respectively to ensure that when the minimum daily iron intake is delivered and there is no overdosing of calcium based on nutritional requirements of the human body (i.e. 1000 mg calcium and 15 mg iron intake per day). The molar ratio of total metal (i.e. final concentration of [Ca] + [Fe]: 8.573 mM) to pyrophosphate ion was based on the stoichiometry of Ca2P2O?. Consequently, the resulting solution was added to Na4P2C>7 solution (final concentration: 4.286 mM), while stirring vigorously using magnetic stir bar. A turbid white dispersion formed during addition after a couple of seconds. The samples were then centrifuged at 3273 g for 15 minutes in 50 ml volume polypropylene (PP) conical centrifuge tubes using the Allegro X-12R Centrifuge following by washing the precipitate twice with water. The dispersions were post-treated for 10 minutes using a Branson Ultrasonics™ CPXH series ultrasonic cleaning bath, CPX8800H model. The remaining precipitate was dried in an oven at 45°C overnight.

TABLE 2

Particle Morphology

An aqueous dispersion of each the particles was dried on a carbon-coated copper grid and analysed by transmission electron microscopy (TEM) and Energy-dispersive X-ray spectroscopy (EDXS) performed on a Talos™ f200X from FEI Company. TEM images analysis indicated that, whilst for Sample A (j=0.005), the particles appeared as homogenous micrometer-sized needles, in the mixed salts containing iron with 0.005<j<0.05 (samples B to E) segregation was evident as coexistence of two phases of particles: Fe-rich (mostly irregular-round shaped particles) and Fe-poor (needle shaped particles). TEM-EDXS results from Sample E (j=0.021 ) suggests that the round-shaped aggregates are iron (III) oxide particles. The mixed salts containing iron with j > 0.05 showed homogenous morphologies for each salt. For j=0.05 (Sample F) and j=0.10 (Sample G), the particles had the form of irregular fractal aggregates of 50 to 80 nm size. Interestingly, perfectly spherical particles were observed for sample I 0=0.26).

These results demonstrate that only salts where the target value of j was > 0.021 displayed a morphology of homogenous, sub micron-sized particles.

Particle composition

For each different salt with homogenous morphology, the elemental composition ratios (i.e. the ratios of atomic percentages [atom%]) obtained from several separate EDXS measurements were used for solving j based on the general formula of the mixed salts (Ca [atom%]/Fe [atom%] = 2(1 — j)/4j , Ca [atom%]/P [atom%] = 2(1 — j)/2 (1 + 2j), Fe [atom%]/P [atom%] = 4j/2(l + 2j)). The average j value for each mixed salt is reported in Table 3 with the corresponding standard deviation.

TABLE 3

Particle solubility

Fresh dispersions of 10 mg/ml salts (Ferric pyrophosphate and Samples F to I) in MilliCi water were prepared and titrated automatically using a pH-stat device (Metrohm, Herisau, Switzerland) by titrants 0.1 M NaOH and 0.1 M HCI solutions to pH 1 to 11 at which 0.5 ml dispersion was isolated in 1.5 ml Eppendorf tubes. The samples were then incubated for 2 hours in Eppendorf Thermomixer® F1.5 at 23°C. After incubation, the final pH of each sample was measured with the same pH-stat device. Subsequently, the samples were centrifuged at 15000 g for 10 minutes using an Eppendorf Centrifuge 5415 R and the supernatant of the samples was isolated for measuring the dissolved iron concentration in them.

Iron concentration in solutions (supernatants) was quantified using a ferrozine-based colorimetric assay (L. L. Stookey, Analytical Chemistry 197042 (7), 779-781). An excess amount of ascorbic acid (50 pL, 100 mM in Milli-Q water) was added to 50 pL sample (the supernatants) ensuring reduction of iron ions from ferric to ferrous state. Complexation of ferrous iron with 3-(2-pyridyl)-5-6-(bis(4-phenylsulfonic acid)-1 ,2,4- triazine (i.e. ferrozine) results in absorbance at A _m ax =565 nm. Eventually, ferrozine (50 pL, 40 mM in Milli-Q water) was added and samples were transferred to 96-well microplates and the absorbance spectra at 565 nm were measured in a SpectraMax M2e (Molecular Devices, Sunnyvale, CA, USA), at room temperature. All measurements were performed in duplicate, quantification of total iron was performed based on intensity (565 nm) and a calibration curve of FeSO4 (0.0078 - 1 mM, in duplicate, R ² > 0.99).

Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) was used for independent verification of the iron quantification by the ferrozine assay. Samples were five times diluted in 0.14 M Nitric acid (HNO3) prior to injection in the ICP system (ICP- OES, Agilent 5110 VDV in dual mode). The elemental composition of iron, calcium, and phosphor was determined using scandium as internal standard. The LOD values of iron, calcium, and phosphor were 0.05 mg/L, 0.05 mg/L, and 0.2 mg/L, respectively.

The results are shown in Tables 4 to 8 in terms of proportion of iron in the particles that is soluble (% Dissolution) and the measured concentration of iron in solution. TABLE 4 - Fe ₄ (P ₂ O ₇ )3

TABLE 5 -SAMPLE F TABLE 6- SAMPLE G

TABLE 7 -SAMPLE H TABLE 8 - SAMPLE I

As can be seen by the data in Tables 4 to 8, the iron in Samples F and G has a lower solubility than in iron pyrophosphate at pH values of 5 to 7; the iron in Sample H has a slightly higher solubility than iron pyrophosphate at pH values of 5 to 7 but still less than 3% of the iron is soluble at pH 6; and the iron in Sample I also has a slightly higher solubility than iron pyrophosphate at pH values of 5 to 7. The iron in in all of Samples F to I has a much higher solubility than iron pyrophosphate at pH values close to 2, with all but Sample I having a solubility much greater than 3% at these pH values.

Conclusions

The foregoing results demonstrate that small multimineral particles with very low levels of iron (target mole fraction of iron in the cations < 0.041) are difficult to produce. With higher levels of iron, homogenous multimineral sub-micron particles can be readily produced. These homogenous particles show low solubility at pH values commonly found in food (pH 5-7) but very high solubility at the acid pH of the stomach, although the solubility at acid pH is less pronounced where the iron content of the particles becomes high (mole fraction of iron in the cations > 0.52). Example 2

A fortified seasoning cube composition and a comparative composition (without iron) are given in Table 9 where all amounts are % by weight. The amount of iron-containing salt from Example 1 (Samples F, G or H), m, is selected to deliver 2.1 mg Iron in each 4 g seasoning cube and depends on the exact composition of the iron-containing mixed mineral salt. The weight % of NaCI in the cube is adjusted to balance the amount of iron- containing salt.

TABLE 9

Preparation of seasoning cubes - Weigh all the materials, with the exception of the fat and the iron-containing salt together in a plastic jar and mix with a mixer (Kenwood Chef Premier KMC650) for 1 minute at speed setting 4. Add the fat in liquid form (heat to melt if necessary) to the mixture, after which the mixture is mixed for 1 minute at speed setting 6. Add the iron-containing salt and mix for a further 1 minute at speed setting 6. Transfer a 4 g portions of this mixture to the pressing block of an Instron press (Instron 5567) and press the cube at 5 kN. This procedure is repeated for each cube.

Test procedure - Off-colour formation is analysed in an accelerated off-colour test. Two cubes are put on a plastic holder and placed in a 100 ml glass jar. 1 g of water is added in the jar in such a way that the cube does not come into direct contact with the water. This procedure simulates typical storage conditions of commercial products, where the water content of seasoning cubes increases over time, but in an accelerated fashion. The jars are closed with a lid and placed in an oven at 40°C for the accelerated test. Colour is measured after 3 weeks.

Colour measurements - Off-colour formation is analysed by a colour measurement as known in the art. A DigiEye Imaging system from VeriVide Ltd is preferably used for the measurements. From photographs under controlled and calibrated conditions the L*a*b* values are determined. The colour difference AE is calculated using the formula: AE = square root of ((Li*-Lo*) ² + (ai*-ao*) ² + (bi*-bo*) ² ). Where Li*, ai* and bi* are the colour values for the sample, and the Lo*, ao* and bo* are the values for the reference relative to equivalent samples without any iron added. A high AE value represents a relatively high amount of off-colour.

Example 3

A fortified low-sodium bouillon cube composition and a comparative composition (without iron) are given in Table 10 where all amounts are % by weight. The amount of iron- containing salt from Example 1 (Samples F, G or H), n, is selected to deliver 2.1 mg iron in each 8 g seasoning cube and depends on the exact composition of the Iron-containing mixed mineral salt. The weight % of native starch in the cube is adjusted to balance the amount of iron-containing salt.

TABLE 10 The compositions are prepared by combining sucrose, soybean oil, and colourants in a vessel with a mixer and mixing for 1 minute at 30 rpm. Subsequently tapioca starch, maltodextrin and other dry ingredients are added, and the mixture is mixed for 30 seconds at 60 rpm. Then the palm oil is liquified by heating, subsequently partly precrystallised in a votator, and added to the mixture. Finally the dried herbs and spices and vegetables and flavours, along with the iron-containing salt are added. The mixture is mixed for 3 minutes at 60 rpm. The resulting paste is extruded on paper packaging material, and subsequently mechanically wrapped into single bouillon cubes. The cubes are pasty, and have a weight of about 8 gram.

Example 4

A fortified cereal-based beverage precursor is prepared from a powder of malted barley, wheat flour, milk solids, sucrose, wheat gluten, table salt, soy protein isolate, acidity regulators and vitamins. To the powder is added an amount of iron-containing salt from Example 1 (Samples F, G or H) selected to deliver 2.1 mg iron in each 20 g serving of the powder. The iron-containing multimineral particles are mixed into the powder to give a visibly homogenous mixture. To prepare an iron-fortified beverage, 20 g of the beverage precursor is stirred into 200 ml of hot milk.