’'METHOD FOR MAKING AN EDIBLE SPHERE CONTAINING A LIQUID MATRIX"

DESCRIPTION

Field of the invention

The present invention relates, in general, to the food and/or nut.raceutical fields. In particular, the present invention relates to a method for making an edible spherical container suitable for containing liquid matrices. Even more specifically, the present invention relates to a method for making an edible spherical container containing hydrophobic or hydroalcoholic liquid matrices.

Description of the prior art

Several techniques are currently known for making edible spherical containers. For example, edible spheres can be produced by means of known direct or indirect spherification methods.

The Applicant observes that, disadvantageously, the known edible spheres produced by direct spherification have a short preservation time and must be consumed rapidly.

Disadvantageously, the known edible spheres produced by reverse spherification have an inner content that is less liquid than that of spheres made by direct spherification.

United States patent US 4,507,327 describes a capsule suitable for containing edible liquid matrices and made of calcium alginate. Disadvantageously, such a container suffers from transudation effects and poor preservation of the liquid matrix contained in said capsule.

International patent application no, WO 2009/022909 A1 describes edible capsules suitable for containing an edible liquid. In particular, such liquid comprises an oil-in-water emulsion, wherein at least one flavorant or colorant is present in the oil phase of the emulsion. The described capsules are made by means of the known direct spherification and reverse spherification processes, and suffer from the above-described disadvantages.

United States patent application no. US 2018/0146704 A1 describes a capsule containing two mutually immiscible or partly miscible phases (e.g. an aqueous phase and a hydrophobic phase or a liquid phase and a solid phase). Such a capsule, formed by a film of calcium alginate, is made by reverse spherification through a system of concentric,tubes.

Brief description of the invention

It is the object of the present invention to provide an alternative method for making an edible spherical container for hydrophobic and hydroalcoholic liquid matrices.

In particular, it is the object of the present invention to provide a method for making an edible sphere containing a liquid matrix, comprising: providing a biphasic sphere comprising a gelatinous polysaccharide membrane enveloping an inner chamber; said inner chamber containing a first aqueous solution comprising a weight percentage of 0.1% to 0.5% of a polysaccharide; wherein said gelatinous polysaccharide membrane has a diameter of 0.5 to 2 cm; inserting a needle into said biphasic sphere to create a hole on the surface of said gelatinous polysaccharide membrane; wherein said needle has a diameter of 0.50 mm to 1 mm; removing said first aqueous solution from said inner chamber by means of said needle; - injecting,, by means of said needle, a liquid matrix into said inner chamber; said liquid matrix being a hydroalcoholic or hydrophobic liquid matrix;

- sealing said hole by depositing on said hole a second aqueous solution comprising a weight percentage of 0.1% to 0.5% of a polysaccharide; said second aqueous solution being deposited by dripping on said hole, thereby obtaining said edible sphere containing said liquid matrix.

Preferably, said edible sphere containing said liquid matrix is immersed into a third aqueous solution containing a weight percentage of 0.1% to 2% of calcium chloride or calcium lactate.

Preferably, said edible sphere containing said liquid matrix is immersed in said third aqueous solution for a time of 2 to 5 minutes. Preferably, said providing a biphasic sphere comprises: preparing said first aqueous solution by dissolving in water a quantity of a polysaccharide of 0.1% to 0.5% by weight of the solution; heating said first aqueous solution; providing a concave mould filled with a thickening aqueous solution containing a weight percentage of 0.1% to 2% of calcium chloride or calcium lactate; pouring said first aqueous solution into said mould, in said thickening aqueous solution; wherein the quantity of said thickening aqueous solution is greater than the quantity of said first aqueous solution;

- circularly stirring said mould containing both said thickening aqueous solution and said first aqueous solution, thereby forming said biphasic sphere.

Preferably, said first aqueous solution is heated to a temperature of 120 °C for a time interval of 15 to 25 minutes.

Preferably, said first aqueous solution is brought to room temperature before being poured into said mould in said thickening aqueous solution.

Preferably, said first aqueous solution and/or said second aqueous solution comprise a weight percentage of 0.1% to 0.5% of a polysaccharide selected from: xanthan gum, guar gum, agar-agar, psyllium gum, tara gum, gellan gum, pectin, potassium alginate, ammonium alginate, calcium alginate, carrageenan, sodium alginate.

Preferably, said gelatinous polysaccharide membrane has a diameter of 0.5 cm to 0.8 cm and said liquid matrix is a hydrophobic liquid matrix.

Preferably, said gelatinous polysaccharide membrane has a diameter of 1 cm to 1.5 cm and said liquid matrix is a hydroalcoholic liquid matrix.

According to a further aspect, the present invention provides a packaged product comprising: a glass container;

- a plurality of edible spheres, each edible sphere comprising a hydroalcoholic or hydrophobic liquid matrix enclosed in a gelatinous polysaccharide membrane having a diameter of 0.5 to 2 cm; wherein said plurality of edible spheres are contained in said container; wherein said plurality of edible spheres are immersed in a preserving liquid contained in said container, said preserving liquid being said hydroalcoholic or hydrophobic liquid matrix (L).

Brief description of the drawings

The invention will become more apparent in light of the following detailed description, provided merely by way of non ^¬ limiting example, wherein reference will be made to the annexed drawings, wherein: Figure 1 shows a biphasic sphere with a hydrophobic matrix obtained by following a method according to the present invention;

Figure 2 shows a section of the biphasic sphere shown in Figure 1, representing a wall of the biphasic sphere;

Figure 3 is a flow chart of a method for making an edible sphere according to the present invention.

Detailed description of some preferred embodiments

With reference to Figures 1 and 2, a generic edible spherical container according to the present invention, containing a liquid matrix, is designated by reference numeral 10.

In the following, said spherical container will be generally referred to as "edible sphere 10".

As shown in Figures 1 and 2, the edible sphere 10 comprises a gelatinous polysaccharide membrane 11.

The gelatinous polysaccharide membrane 11 envelops an inner chamber 12. The inner chamber 12 contains a liquid matrix L.

According to the present invention, the liquid matrix L may be either a hydrophobic liquid matrix or a hydroalcoholic liquid matrix. For example, the hydrophobic matrix is an oil.

For example, the hydroalcoholic matrix is an alcoholic, beverage, e.g. still wine or myrtle liqueur.

Preferably, the gelatinous polysaccharide membrane 11 has a maximum diameter D of 2 cm. A larger diameter D of the gelatinous polysaccharide membrane 11 would, in fact, adversely affect its sphericity, structure and texture.

Preferably, the diameter D of the gelatinous polysaccharide membrane 11 is 0.5 to 2 cm. Alternatively,, the diameter D of the gelatinous polysaccharide membrane 11 is 0.8 cm to 1 cm, alternatively 1 cm to 1.5 cm, alternatively 1.5 cm to 2.0 cm.

The selection of the diameter D of the gelatinous polysaccharide membrane 11 is made on the basis of the type of liquid matrix contained in the inner chamber 12 of the edible sphere 10.

Preferably, edible spheres 10 having a diameter in the range of 0.4 to 0.8 cm contain hydrophobic liquid matrices L.

Preferably, biphasic spheres 10 having a diameter in the range of 1.0 to 1,5 cm contain hydroalcoholic liquid matrices L.

Preferably, according to the present invention, the gelatinous polysaccharide membrane 11 of the edible sphere 10 is seamless.

Advantageously, this seamless design permits obtaining an edible sphere 10 having an improved appearance.

According to the present invention, the edible sphere .1.0 is made starting from a biphasic sphere.

Such biphasic sphere comprises a gelatinous polysaccharide membrane enveloping an inner chamber. The inner chamber of the biphasic sphere contains a first aqueous solution.

The biphasic sphere has a diameter D of 0.5 to 2 cm.

The first aqueous solution comprises a weight percentage of 0.1% to 0.5% of a polysaccharide having jellying properties. Preferably, the first aqueous solution comprises a weight percentage of 0.1% to 0.5% of a polysaccharide selected from: xanthan gum, guar gum, agar-agar, psyllium gum, tara gum, gellan gum, pectin, potassium alginate, ammonium alginate, calcium alginate, carrageenan, sodium alginate.

Preferably, according to the present invention, the production of such biphasic sphere occurs through the steps described below.

With reference to Figure 3, during a preparation step 101 a quantity a polysaccharide having jellying properties of 0.1% to 0.5% by weight is dissolved in water. Preferably _/ a quantity of polysaccharide of 0.3% by weight is dissolved in water.

Preferably _/ the polysaccharide dissolved in water at step 101 is selected from: xanthan gum, guar gum, agar-agar, psyllium gum, tara gum, gellan gum, pectin, potassium alginate, ammonium alginate, calcium alginate, carrageenan, sodium alginate.

In the following, the aqueous solution prepared at step 101 will be referred to as "first aqueous solution".

Preferably, the first aqueous solution is heated to a temperature of 100 °C to 120 °C, preferably 120 °C. Preferably, the first aqueous solution is heated for a time interval of 15 to 25 minutes.

For example, the first aqueous solution is poured into a suitable container arranged on an induction plate adapted to heat, preferably at constant temperature, the first aqueous solution.

Once dissolved in water, the polysaccharide acts as a jellying thickening agent, i.e. it acquires jellying properties when heated for a certain time interval.

Preferably, at the end of step 101 a mould preparation step 102 is carried out. During step 102 a suitable mould is provided. For example, said mould is a concave mould having a capacity of 2.5 to 5 mL.

During step 102, said mould is filled with a thickening aqueous solution. Preferably, such thickening aqueous solution is an aqueous solution comprising calcium chloride or calcium lactate at a concentration of 0.1% to 2% by weight of the solution. For example, the thickening aqueous solution is an aqueous solution of calcium chloride having a concentration of 1% by weight of the solution.

At the end of step 102, a diphasic sphere preparation step 103 is started. During step 103, a quantity of the first aqueous solution (prepared at step 101) is poured into the mould filled with the thickening aqueous solution (prepared at step 102). Preferably, the first aqueous solution poured into the mould filled with the thickening aqueous solution at step 103 is at room temperature.

Preferably, the ratio between the quantity of first aqueous solution poured into the mould and the quantity of thickening aqueous solution contained in the mould is equal to or smaller than 1:2.

For example, considering a concave mould having a capacity of 2.5 ml filled with 2.5 ml of thickening aqueous solution, 0.8 ml of first aqueous solution will preferably be poured. Considering a concave mould having a capacity of 5 mL filled with 5 rtiL of thickening aqueous solution, 1 mL of first aqueous solution will preferably be poured.

For example, considering concave moulds having a capacity of 2.5 mL, filled with an aqueous solution comprising calcium chloride at a concentration of 1% by weight of the solution, in each one of such moulds 0.8 mL of aqueous solution containing sodium alginate (prepared at step 101) will be poured.

According to a preferred embodiment, the polysaccharide employed for preparing the first aqueous solution is sodium alginate. For example, the first aqueous solution contains an amount of sodium alginate of 0.1% to 0.5% by weight of the solution. Preferably, during step 101 said first aqueous solution is heated to a temperature of 120 °C for about 15-25 minutes, more preferably 20 minutes.

The Applicant points out that it is not advisable to use a heating system wherein water boils under pressure. The Applicant observes that boiling water under pressure would lead to the generation of saturated steam that, condensing on the aqueous solution, would raise the temperature to values in excess of 120 °C. Over 120 °C, the structure of the biphasic sphere - and hence the gelatinous membrane 11 - is no longer "solid". In other words, if a temperature of 120°C is exceeded during step 101, the gelatinous membrane 11 of the edible sphere 10 obtained in accordance with the present invention will tend to lose its shape.

Preferably, during step 103 the mould containing both the thickening aqueous solution and the first aqueous solution is circularly stirred for a time interval of 2 to 8 seconds; even more preferably, such circular stirring is performed for 5 seconds. For example, the mould (containing both the first aqueous solution --- prepared at step 101 - and the thickening aqueous solution) is arranged on a stirrer that circularly stirs both the first aqueous solution and the thickening aqueous solution contained in the mould.

It should be noted that a biphasic sphere will be obtained at the end of step 103. The term "biphasic sphere" refers to a gelatinous sphere having a liquid inner core composed of the first aqueous solution and a gelatinous polysaccharide membrane. The gelatinous polysaccharide membrane of the biphasic sphere corresponds to the gelatinous polysaccharide membrane 11 of the edible sphere 10 according to the present invention.

Subsequently, a solidification step 104 is started. During step

104, the biphasic sphere obtained at step 103 is removed from the mould and immersed in a second thickening aqueous solution.

Preferably, the second thickening aqueous solution used in step

104 is similar to the thickening aqueous solution used in step 103.

In particular, for example, the second thickening aqueous solution is an aqueous solution comprising calcium chloride - or calcium lactate - at a concentration of 0.1% to 2% by weight of the solution, preferably 1% by weight of the solution.

Preferably, during step 104 the biphasic sphere is kept soaking in the second thickening aqueous solution for a time of 60 seconds.

It should be noted that, as it comes in contact with the polyvalent metal cations of the thickening aqueous solution added at step 104 (e.g. an aqueous solution comprising calcium chloride at a concentration of 1% by weight), the outer surface of the biphasic sphere obtained at step 103 will get further hardened, thus assuming a well-defined shape and volume.

Even more specifically, at the end of step 104, such biphasic spheres will show an outer envelope having a thickness of 0.05 mm to 0.4 mm, preferably 0,05 mm to 0.1 mm.

At the end of step 104, a step of emptying and filling the biphasic sphere 105 is started.

At the beginning of step 105, the inner content of the biphasic sphere is removed; this operation will be hereafter also referred to as "stomatization".

In particular, the biphasic sphere obtained at the end of step 103 or step 104 is pierced by means of a needle. During step 105, such needle permits removing the liquid from the inside of the biphasic sphere, obtaining a structure with containment walls which is internally empty.

Such internally empty structure with containment walls is then filled, by means of the same needle, with a desired quantity of liquid matrix L,

At step 105, the (previously made) hole on the surface of the gelatinous polysaccharide membrane 11 is sealed by means of a drop of a thickening and jellying aqueous solution, thereby obtaining an edible sphere 10 containing the desired liquid matrix L, In particular, such drop of thickening and jellying aqueous solution is applied onto the surface of the edible sphere 10 by dripping. Even more in particular, such drop of thickening and jellying aqueous solution is applied onto the surface of the gelatinous polysaccharide membrane 11 by dripping by means of a dosing device.

Preferably, the further thickening and jellying aqueous solution corresponds to the first aqueous solution (prepared at step 101).

Preferably, the diameter of the needle employed during step 105 is selected as a function of the diameter of the biphasic sphere. Preferably _/ the ratio between the diameter of the needle and the diameter of the biphasic sphere is smaller than or equal to 20, Even more preferably _/ the ratio between the diameter of the needle and the diameter of the biphasic sphere is in the range of 10 to 20.

Preferably _/ considering a biphasic sphere having a diameter of 0.5 to 2 cm, the diameter of the needle will be in the range of 0.50 mm to 1 mm, preferably 0.50 mm to 0.80 mm (equivalent to 25 G and 21 G).

The Applicant observes that needle diameters smaller than 0.50 (e.g. from 0,20 mm to 0,45 mm) make injecting the liquid matrix L difficult, resulting in the possible formation of air bubbles, especially when injecting hydrophobic liquid matrices L, due to their high viscosity.

As an alternative, it is possible to use needles of sizes greater than specified above (e.g. from 0.90 mm to 1,60 mm, equivalent to 20 G and 16 G). In order to obtain an edible sphere 10 with no visible seams on its surface, such needles should only be used on edible spheres 10 having a diameter in excess of 2 cm.

The use of needle sizes greater than 0,90 mm may lead to structural cracks in the walls of spheres having a diameter smaller than 2 cm.

At the end of step 105, a stabilization step 106 is preferably started. During step 106, the edible sphere 10 is immersed in a third thickening solution for a time interval of 1 to 4 minutes, preferably 3 minutes.

Preferably, the third thickening solution is similar to the thickening solution used in step 103 or the second thickening aqueous solution used in step 104,

For example, the third thickening aqueous solution is an aqueous solution comprising calcium chloride - or calcium lactate - at a concentration of 0.1% to 2% by weight of the solution, preferably 1% by weight of the solution. At the end of step 106, the edible sphere 10 according to the present invention will be obtained.

Preferably, the edible sphere 10, made as described above, is placed into a glass container, more preferably into an aseptic glass container.

Preferably, such container is kept at room temperature (+20

°C).

Preferably, such glass container contains a plurality of edible spheres 10 containing the same liquid matrix L. Preferably, such aseptic glass container is filled, at least partly, with a preserving liquid. In particular, the preserving liquid employed corresponds to the (hydrophobic o hydroalcoholic) liquid matrix L contained in the edible spheres 10 stored in the glass container.

Examples of particularly preferred embodiments

Example 1 - Making edible spheres 10 containing single-variety extra virgin olive oil (EVOO).

In this example, edible spheres 10 were made which had a diameter of 0.5 cm or 0.8 cm. Such edible spheres 10 contained single-variety EVOO oil (hydrophobic liquid matrix L) and were prepared as previously described herein.

In particular, such edible spheres 10 containing single-variety EVOO oil were produced as follows: preparing a solution of water and sodium alginate at 0.3% (w/w) by weight of the solution (step 101); pouring 0.8 mL of such solution into a concave spherical mould having a capacity of 2.5 mL, containing a solution of calcium chloride at 1% (w/w), circularly stirring said mould for approx. 5 seconds, thereby obtaining a biphasic sphere (steps 102 - 103); immersing the biphasic sphere in a 1% solution of calcium chloride (step 104); stomatizing the biphasic sphere by means of a needle (having a diameter of 0.7 mm and a length of 32 mm). In particular, following the exertion of light pressure on the surface of the biphasic sphere, the gelatinous content of the biphasic sphere was removed to obtain an empty sphere. Through the same needle, single-variety EVOO oil was injected to fill up the previously emptied sphere, thereby obtaining the edible sphere 10 (step 105); applying a drop of sodium alginate at 0.3% (w/w) by weight, of the solution onto the previously created hole to seal the edible sphere 10 (step 105); immersing the sealed edible sphere 10 in a 1% solution of calcium chloride for approx. 3 minutes (step 106).

The Applicant observes that step 106 improves the sealing and strengthens the walls of the edible sphere 10. The walls of the edible sphere 10 have a glossy, non-opaque appearance, allowing the naked eye to see the single-variety EVOO oil contained therein.

In this example, the edible spheres obtained by following the above- described method can be packaged at room temperature into containers (preferably made of transparent glass to allow the consumer to see their contents) containing a preserving liquid consisting of the same hydrophobic liquid, i.e. the single-variety EVOO oil.

The edible spheres 10 containing single-variety EVOO oil are suitable for human consumption and have a minimum shelf-life of approximately four months. Example 2 - Making edible spheres encapsulated with a hydroalcoholic beverage consisting of myrtle liqueur.

In this example, edible biphasic spheres 10 were made which had a diameter of 0.8 cm or 1.0 cm and contained a hydroalcoholic liquid matrix consisting of myrtle liqueur.

In particular, such edible spheres 10 containing myrtle liqueur were produced as follows: preparing a solution of water and sodium alginate at 0.3% (w/w) by 'weight of the solution (step 101); pouring 0.8 ml of such solution into a concave spherical,mould having a capacity of 2.5 mL, containing a solution of calcium chloride at 1% (w/w), circularly stirring said mould for approx. 5 seconds, thereby obtaining a biphasic sphere (steps 102 -

103); immersing the biphasic sphere in a 1% solution of calcium chloride (step 104); stomatizing the biphasic sphere by means of a needle (having a diameter of 0.7 mm and a length of 32 mm). In particular, following the exertion of light pressure on the surface of the biphasic sphere, the gelatinous content of the biphasic sphere was removed to obtain an empty sphere. Through the same needle, myrtle liqueur was injected to fill up the previously emptied sphere, thereby obtaining the edible sphere 10 (step 105); applying a drop of sodium alginate at 0.3% (w/w) by weight of the solution onto the previously created hole to seal the edible sphere 10 (step 105); immersing the sealed edible sphere 10 in a 1% solution of calcium chloride for approx. 3 minutes (step 106).

The edible spheres 10 containing myrtle liqueur obtained as described above can be packaged at room temperature into containers (preferably made of transparent glass) containing a preserving liquid consisting of the same hydroalcoholic matrix, in this case Myrtle liqueur.

The edible spheres 10 containing myrtle liqueur made as described above have a minimum shelf-life of approximately four months.

The edible spheres 10 containing myrtle liqueur can be cooled, e.g. to +4 °C, prior to being served as an alternative form of tasting the alcoholic beverage or as an accompaniment to sweets and desserts.

Example 3 --- Making edible spheres encapsulated with a hydroalcoholic beverage consisting of still wine.

In this example, edible biphasic spheres 10 were made which had a diameter of 1.0 cm or 1.5 cm and contained a hydroalcoholic liquid matrix consisting of still wine.

In particular, such edible spheres 10 containing still wine were produced as follows: preparing a solution of water and sodium alginate at 0.3% (w/w) by weight of the solution (step 101); pouring 0.8 mL of such solution into a concave spherical mould having a capacity of 2.5 mL, containing a solution of calcium chloride at 1% (w/w), circularly stirring said mould for approx. 5 seconds, thereby obtaining a biphasic sphere (steps 102 - 103); immersing the biphasic sphere in a 1% solution of calcium chloride (step 104); stomatizing the biphasic sphere by means of a needle (having a diameter of 0.7 mm and a length of 32 mm). In particular, following the exertion of light pressure on the surface of the biphasic sphere, the gelatinous content of the biphasic sphere was removed to obtain an empty sphere. Through the same needle, still wine was injected to fill up the previously emptied sphere, thereby obtaining the edible sphere 10 (step 105); applying a drop of sodium alginate at 0.3% (w/w) by weight of the solution onto the previously created hole to seal the edible sphere 10 (step 105); immersing the sealed edible sphere 10 in a 1% solution of calcium chloride for approx. 3 minutes (step 106).

The edible spheres 10 containing still wine obtained as described above can be packaged at room temperature into containers (preferably made of transparent glass) containing a preserving liquid consisting of the same hydroalcoholic matrix, in this case still wine.

The edible spheres 10 containing still wine made as described above have a minimum shelf-life of approximately four months.

The edible spheres 10 containing still wine can be cooled, e.g. to +4 °C, prior to being served as an alternative form of tasting the alcoholic beverage or as an accompaniment to sweets and desserts.

The Applicant points out that, the liquid matrix being the same, edible spheres 10 of different sizes can be obtained by increasing the quantity of first aqueous solution poured into the concave spherical mould (having a suitable capacity) during step 103.

The present invention offers some important advantages.

In particular, the method according to the present invention allows for fast production of biphasic spheres or edible spheres 10 having different diameters.

The edible spheres 10 according to the present invention offer the consumer a product having good visual quality, thanks to the glossiness and transparency of the walls of the container obtained by means of the above-described production method.

Furthermore, the sealing (step 106) permits obtaining a wall of the edible sphere 10 (i.e. the gelatinous membrane 11) without any thickened spots.

Advantageously, the edible spheres 10 according to the present invention have a gelatinous membrane 11 having a bright, transparent and glossy outer surface. Moreover, said gelatinous membrane 11 is resistant to lysis and osmosis.

Advantageously, the edible spheres 10 made as described above can be stored for a long time, up to 6 months, at room temperature, preferably at +20 °C (room temperature), with no alteration of the characteristics of the liquid matrix L contained therein.

Preferably, oil-containing edible spheres 10 placed in a glass container containing oil (used as preserving liquid) should not be stored at temperatures exceeding 40°C. Temperature values in excess of 40°C would accelerate the oxidation process, resulting in oil deterioration .

Preferably, oil-containing edible spheres 10 placed in a glass container containing oil (used as preserving liquid) should not be stored at temperatures below 0°C. Temperatures lower than 0°C would cause the oil contained therein to freeze, resulting in structural modifications and/or variations in the colour of the edible sphere.

Advantageously, the method described herein is carried out at room temperature, so that hydrophobic and hydroalcoholic liquid matrices can be used without requiring any stabilizing additives, and can be injected directly into the edible sphere 10.

Advantageously, according to the above-described method it is not necessary to resort to freezing (frozen spherification) in order to mutually encapsulate immiscible or partly miscible matrices. Advantageously, the edible spheres 10 can be marketed at room temperature packaged in different food-grade containers, preferably glass containers, thus enhancing the characteristics of the product.