Patent Description:
It is known to provide texture and mouthfeel to food and beverage product by protein aggregation. There continues to be a need for food and beverages products exhibiting nutritional balance of macronutrients while delivering great taste and texture.

<CIT> describes a process to obtain a heat convection drying protectant preparations for lactic bacteria or probiotics consisting in heat treating at <NUM> a milk preparation enriched with calcium in order to induce protein aggregation and subsequently submitting the preparation to a mechanical homogenization treatment. This patent application does not relates to beverage preparation.

<CIT> disclosing the production of a free divalent cations-rich liquid food product in which <NUM>% of the lysine residues carried out by the proteins have been glycosylated in order to increase their resistance to aggregation in presence of calcium. Therefore, <CIT> is related to preventing protein aggregation in presence of divalent cations, calcium among others.

<CIT> is describing a process for the production of a milk protein concentrate which is enriched with whey proteins. Skimmed milk is heated in the pH range <NUM>-<NUM> in order to promote aggregation of whey proteins together with caseins. The heated product is subsequently submitted to filtration in order to concentrate protein aggregates and to remove lactose. <CIT> is not concerned with the preparation of shelf stable beverages.

] described the effect of addition of free calcium on the viscosity of superphosphorylated caseins. It was shown that the viscosity of a <NUM> wt. % superphosporylated caseins (<NUM>% phosphorylation) increased by addition of <NUM> calcium at pH <NUM>. This study does not cover beverage products. Further, for beverage products the superphosporylated caseins are not desirable relevant as chemically modified and expensive ingredient.

<NPL>] reported that the amount of free calcium ions in bovine milk at pH <NUM> was <NUM> and that this value decreased to <NUM> when milk pH decreased to <NUM>. This study does not describe protein aggregation resulting from interaction with free calcium ions.

<NPL>] investigated the effect of calcium chloride addition to skimmed milk reconstituted at <NUM> wt. % in the pH range <NUM> - <NUM> and the subsequent effect on viscosity when the milks were heated for <NUM> minutes at <NUM>, <NUM> and <NUM>. They reported a critical instability pH of <NUM> for the milks upon heating at <NUM> for calcium chloride content up to <NUM>. The article by I. McKinnon is silent about how to make beverage products with a good shelf-life stability.

<NPL>] determined the impact of calcium chloride addition into full fat milk (<NUM>% fat) upon heating at <NUM>. It was reported that calcium chloride addition below <NUM> was leading to viscous dispersions while higher calcium chloride concentrations induced formation of stronger gels. Interestingly, pre-treatment of the milk at <NUM> for <NUM> minutes before calcium chloride addition and subsequent heating at <NUM> was leading to the strongest gels. Gel formation is not desirable in shelf stable beverages.

] reported that addition of calcium chloride to β-lactoglobulin at pH <NUM> was leading to microgels or gel formation upon heating at <NUM> or <NUM> when calcium content was <NUM>-<NUM> for a protein concentration of <NUM> wt. Gel formation is not desirable in shelf stable beverages.

<CIT> discloses shelf stable ready to drink beverages comprising hydrolysed whole grain and a stabilizing system comprising high acyl gellan gum.

<CIT> discloses beverage products with a protein system induced by controlled aggregation of milk proteins which imparts outstanding sensory attributes.

<CIT> discloses ready to drink low sugar flavored dairy beverages comprising a first stabilizing component and a second stabilizing component. The first stabilizing component is microcrystalline cellulose, carboxymethyl cellulose and further comprising carrageenans, and the second stabilizing component is at least one of gellan or a modified starch.

<CIT> discloses calcium-enriched and phosphorus-enriched fortified milk with minimal settling of the calcium source, acceptable flavor, and acceptable viscosity and mouthfeel. It is made by the additon of tri basic calcium phosphate, carrageenan and guar gum to fresh milk.

The prior art teaching shows that although viscosity may be obtained with calcium addition and gelling is a well know effect but this is undesirable in beverage production. Furthermore, the pH of the product is close to neutral and influence of divalent ions and heat treatment process may lead to instability of the RTD beverage product during shelf life. The prior art does not show how to provide RTD beverage products delivering desirable taste and texture while maintaining good physical stability during product shelf-life.

For RTD products stability is critical during shelf life especially for storage at ambient temperatures. For example it is important to avoid serum, marbling, sedimentation or gelation.

Thus, there is a need for beverage products which are low in fat while having same or improved mouthfeel and texture while delivering good physico-chemical stability during product shelf-life.

It is thus the object of present invention to provide a method for producing a shelf-stable ready-to-drink beverage with improved texture and mouthfeel.

The present invention provides the improvement by the use of milk protein-based aggregates by specific heat treatment in the presence of a specific concentration of added divalent cations.

In a first aspect, the invention relates to a method of producing a shelf stable ready-to-drink beverage product, comprising the steps of:.

The present invention uses milk protein-based aggregates that are generated upon heat treatment in presence of added-free divalent cations in combination of hydrocolloids to deliver optimum sensorial properties while allowing a reduction of the total fat and/or sugar content in the product, as well as good physical chemical stability during product shelf-life. In addition, the described invention enables formulation of dairy-based texturized products which are shelf stable with stabilizing system comprising specific range of hydrocolloids. Content of hydrocolloids below this range may lead to sedimentation and/or serum separation. Addition of hydrocolloids above this range might result in gelation.

When carrying out experiments on the effect of divalent cations addition, in particular calcium, to milk on protein aggregation and viscosity built up, it was surprisingly found that there is a critical range of divalent cations addition leading to optimum protein aggregation without precipitation or gelation of the formed aggregates upon heating. When this optimum concentration of calcium is passed, the system either exhibited over-aggregation with precipitation or a decrease of aggregate size.

Without being bound to theory, it is likely that calcium chloride addition to proteins is leading to an exchange between the protons adsorbed at the surface of the proteins and the calcium ions which have a higher affinity. This phenomenon resulted in a decrease of electrostatic repulsions between proteins as well as possible crosslinking of proteins by calcium cations. In these conditions, subsequent heat treatment of milk or milk based dispersions and emulsions is leading to a controlled aggregation of the proteins which was shown to affect positively the textural and sensorial properties of the finished products.

A major advantage of this invention is that it allows to texturize reduced fat milk-protein based systems, as well as good physical chemical stability during entire product shelf-life.

In the present context the agglomerates created with the method according to the invention and present in the product of the invention have a size of <NUM> - <NUM> microns as measured by D(<NUM>,<NUM>) mean diameter. The agglomerate particle size distribution (PSD) is measured using a laser particle size analyser such as a Mastersizer <NUM> (Malvern Instruments, UK). For the measurements a sample may e.g. be dispersed in the Hydro SM measuring cell until an obscuration rate of <NUM>-<NUM>% is obtained and then analysed in the Mastersizer.

Further in the present context the free divalent cations may be measured by means of a selective electrode. For example, free (ionic) calcium concentration is determined by a Thermo Scientific <NUM> BNWP Ionplus® Sure-Flow® calcium ion selective electrode (ISE) (Thermo Scientific,Chelmsford, MA, USA). The electrode connected to a Thermo Scientific Orion Star A214 pH/ISE meter (Thermo Scientific, Chelmsford, MA, USA) with a waterproof BNC connector. Optimum Results™ A filling solution (Thermo Scientific, Cat. No. <NUM>) is used to fill the electrode.

Further in the present context unless otherwise indicated % of a component means the % of weight based on the weight of the composition, i.e. weight/weight %.

In accordance with the invention the divalent cation is Ca. This divalent cation is food grade and do not provide for easy oxidation.

Advantageously, the divalent cations are added to until the free divalent cations concentration is <NUM> - <NUM> and most preferred <NUM> - <NUM> divalent cations.

Furthermore, the divalent calcium is from a source selected from the group consisting of calcium chloride, calcium lactate, calcium gluconate, calcium acetate, calcium fumarate, calcium malate, calcium phosphate, fractionated calcium from milk source, or a combination thereof. In a particular preferred embodiment of the invention the calcium salt is calcium lactate.

In an all-natural embodiment of the invention the calcium is obtained from concentrated minerals from milk after separation of the protein, fat and lactose by e.g. membrane fractionation.

According to the invention the method comprises a stabilizing system consisting of gellan gum. Furthermore, stabilizing system may further comprises <NUM> - <NUM> wt. % guar gum. It has been found that the specific range of gellan and guar gums in combination with specific range of calcium provide stability of the product at <NUM>, <NUM> and <NUM> during a <NUM> month of storage. The gellan gum is high acyl with a level of acylation of <NUM> - <NUM> %.

The aggregates have a particle size of <NUM> - <NUM> microns, preferably <NUM> - <NUM> microns as D(<NUM>,<NUM>) mean diameter as measured by laser diffraction. This give a desirable mouth feel to the product without the aggregates providing grittiness.

The ingredient composition for the method according to the invention may comprises from <NUM> - <NUM> wt. % milk fat, preferably <NUM> - <NUM> wt. %, more preferably <NUM> - <NUM> wt. %, most preferably <NUM> - <NUM> wt. % of milk fat.

The milk proteins in the ingredient composition are selected from raw milk, pasteurized milk, low and medium heat concentrated milk, low and medium heat milk powder, micellar casein, low and medium heat milk protein concentrate, buttermilk, low and medium heat milk protein isolate or milk powder, whey protein concentrate, whey protein isolate, sweet whey, acid whey, demineralized whey, beta-lactoglobulin or a combination of thereof.

The protein source of the composition may also be obtained from the corresponding raw materials by processing and extraction techniques familiar to a person skilled in the art.

According to the invention a no or low fat product may be obtained with a good mouthfeel and texture and physical chemical stability during product shelf-life. The product may comprises from <NUM> - <NUM> wt. % milk fat, preferably <NUM> - <NUM> wt. %, more preferably <NUM> - <NUM> wt. %, most preferably <NUM> - <NUM> wt. % of milk fat.

According to the invention, the product may comprises sucrose, preferably <NUM> - <NUM>, more preferably <NUM> - <NUM> wt % sucrose.

The present invention is illustrated further herein by the following non-limiting examples.

In this and in the all other examples of the invention, concentrations of ingredients are given as wt/wt. % based on the whole product formulation.

Fluid milk containing <NUM>% milkfat was used in preparation of all samples described in the examples below.

The RTD beverages are made by the following process:.

The RTD beverage was prepared as in Example <NUM> process, using <NUM> of skim milk, <NUM> of milk cream, <NUM> of whey milk powders, <NUM> of high acyl gellan gum, <NUM> of guar gum, <NUM> sugar, <NUM> of cocoa, <NUM> of calcium lactate pentahydrate and water necessary to reach <NUM> of the final beverage.

Particle size distribution determined by using a laser light scattering Mastersizer <NUM> MA(Malvern Instrument) equipped with Hydro <NUM> dispersion unit is shown in <FIG> in comparison between milk produced without added calcium source and invention produced with calcium. The <FIG> shows protein aggregation in the invention produced with calcium.

Beverage physico-chemical properties were evaluated and sensory characteristics were judged by trained sensory panelists. It was found that the RTD beverage significantly improved texture/mouthfeel (improvement is significant if normalized sensory score is equal or above <NUM>) having normalized sensory texture attribute ~ of <NUM> (<FIG>). The invention beverage also had homogeneous visual appearance.

The RTD beverage with controlled protein aggregation was prepared as in Example <NUM>, but using <NUM> of calcium lactate pentahydrate.

Beverage physico-chemical properties were evaluated and sensory characteristics were judged by trained sensory panelists. It was found that the RTD beverage significantly improved texture/mouthfeel having normalized sensory texture attribute of <NUM> (<FIG>). The invention beverage also had homogeneous visual appearance.

Beverage physico-chemical properties were evaluated and sensory characteristics were judged by trained sensory panelists. It was found that the RTD beverage significantly improved texture/mouthfeel having normalized sensory texture attribute of <NUM> (<FIG>). However, phase separation and gelation was found during the storage.

Viscosities of beverages with addition of <NUM>, <NUM>, <NUM> and <NUM> of calcium lactate pentahydrate are shown in <FIG>. Viscosity of the all above beverages were significantly higher than that of the reference prepared without addition of calcium lactate pentahydrate.

Viscosities of beverages with <NUM> and <NUM> of calcium lactate pentahydrate are statistically the same, while increasing concentration of calcium lactate pentahydrate in the beverages decreased their viscosity. Addition of calcium lactate pentahydrate at <NUM> and above creates physical instability.

The RTD beverage with controlled protein aggregation was prepared as in Example <NUM>, but without addition of high acyl gellan gum.

Beverage physico-chemical properties were evaluated and sensory characteristics were judged by trained sensory panelists. The beverage physical instability issues (i.e. phase separation such as sedimentation, marbling) were found.

The RTD beverage with controlled protein aggregation was prepared as in Example <NUM>, but with addition of <NUM> of high acyl gellan gum and without guar gum.

Beverage physico-chemical properties were evaluated and sensory characteristics were judged by trained sensory panelists. The beverage showed no increase in viscosity and instability issues (i.e. phase separation such as serum, sedimentation, and marbling) were found.

The RTD beverage with controlled protein aggregation was prepared as in Example <NUM>, with <NUM> of high acyl gellan gum and without guar gum.

Beverage physico-chemical properties were evaluated and sensory characteristics were judged by trained sensory panelists. It was found that the RTD beverage showed significantly improved texture/mouthfeel having normalized sensory texture attribute of <NUM>. The invention beverage also had homogeneous visual appearance.

The RTD beverage with controlled protein aggregation was prepared as in Example <NUM>, with <NUM> of calcium lactate pentahydrate.

Beverage physico-chemical properties were evaluated and sensory characteristics were judged by trained sensory panelists. It was found that the RTD beverage had no change in viscosity and sensory texture attribute. However, the invention beverage had homogeneous visual appearance.

Beverage physico-chemical properties were evaluated and sensory characteristics were judged by trained sensory panelists. It was found that the RTD beverage significantly improved texture/mouthfeel having normalized sensory texture attribute of <NUM>. The invention beverage also had homogeneous visual appearance.

It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.

Claim 1:
A method of producing a shelf stable ready-to-drink beverage product, comprising the steps of:
providing an ingredient composition comprising micellar caseins and whey protein, having a total protein concentration of <NUM> - <NUM> wt. %, and wherein the composition has a casein to whey protein ratio of <NUM>/<NUM> - <NUM>/<NUM>,
adding divalent cations to provide a concentration of <NUM> - <NUM> free divalent cations in the ingredient composition, and <NUM> - <NUM> wt % of high acyl gellan gum with a level of acylation of <NUM> - <NUM> %, and subsequently
heat treating the ingredient composition at ultra high temperature (UHT) at <NUM> -<NUM> for <NUM> - <NUM> to form agglomerated proteins comprising casein and beta-lactoglobulin from the whey protein, the agglomerates having a size of <NUM> - <NUM> microns mean diameter D(<NUM>,<NUM>) as measured by laser diffraction;
wherein the divalent cation is calcium from a source selected from the group consisting of calcium chloride, calcium lactate, calcium gluconate, calcium acetate, calcium fumarate, calcium malate, calcium phosphate, fractionated calcium from milk source, or a combination thereof.