Beverage product with free divalent cations protein aggregation and a method producing thereof

Abstract

The invention relates to 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 1.5-8 wt. %, and wherein the composition has a casein to whey protein ratio of 90/10-60/40, adding divalent cations to provide a concentration of 3-20 mM free divalent cations in the ingredient composition, and 0.025-0.3 wt % of a stabilizing system comprising hydrocolloids, and subsequently heat treating the ingredient composition at ultra high temperature (UHT) at 135-150° C. for 3-30 s to form agglomerated proteins comprising casein and beta-lactoglobulin from the whey protein, the agglomerates having a size of 5-30 microns mean diameter D(4,3) as measured by laser diffraction. The invention also relates to a shelf stable ready-to-drink beverage product comprising aggregated proteins comprising micellar caseins and whey protein aggregates, wherein the product has a pH of 6.6-7.2, 1.5-8.0 wt. % milk proteins, a casein to whey protein ratio of 90/10-60/40, and a concentration of 3-20 mM divalent cations, and the aggregates are of 5-30 microns mean diameter D(4,3) as measured by laser diffraction.

Claims

1. A method of producing a ready-to-drink beverage product, the method comprising: providing an ingredient composition comprising micellar caseins and whey protein, the ingredient composition having a total protein concentration of 1.5-8 wt. %, and the ingredient composition has a micellar caseins to whey protein ratio of 90/10-60/40; adding a source of divalent cations to the ingredient composition to provide a concentration of 3-20 mM free divalent cations in the ingredient composition, and adding 0.025-0.3 wt % of a stabilizing system comprising a hydrocolloid to the ingredient composition; and subsequently heat treating the ingredient composition at an ultra-high temperature (UHT) of 135-150° C. for 3-30 s to form agglomerated proteins comprising casein and beta-lactoglobulin from the whey protein, the agglomerated proteins having a size of 5-30 microns mean diameter D.sub.(4,3) as measured by laser diffraction.

2. The method according to claim 1, wherein the ingredient composition is subjected to a homogenization, and the homogenization is before the heat treating of the ingredient composition.

3. The method according to claim 1, wherein the divalent cations are selected from the group consisting of Ca.sup.2+, Mg.sup.2+, and combinations thereof.

4. The method according to claim 1, wherein the free divalent cations concentration is 4-8 mM.

5. The method according to claim 1, wherein the source of divalent cations is selected from the group consisting of calcium chloride, calcium lactate, calcium lactate pentahydrate, calcium gluconate, calcium acetate, calcium fumarate, calcium malate, calcium phosphate, fractionated calcium from milk source, and combinations thereof.

6. The method according to claim 1, wherein the ingredient composition comprises sucrose.

7. The method according to claim 1, wherein the hydrocolloid in the stabilizing system is selected from the group consisting of gellan gum, guar gum, locust bean gum, acacia gum, pectin and combinations thereof.

8. The method according to claim 1, wherein the agglomerated proteins have a particle size of 5-30 microns mean diameter D.sub.(4,3) as measured by laser diffraction.

9. The method according to claim 1, wherein the ingredient composition comprises from 0-4 wt. % milk fat.

10. The method according to claim 1, wherein the micellar caseins and/or the whey protein in the ingredient composition are provided in a form selected from the group consisting of raw milk, pasteurized milk, low and medium heat concentrated milk, low and medium heat milk powder, 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 and combinations thereof.

11. The method according to claim 1, wherein the whey protein is not denatured.

12. The method according to claim 1, wherein the agglomerated proteins have a particle size of 6-15 microns mean diameter D.sub.(4,3) as measured by laser diffraction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows particle size distribution of milk without added calcium and RTD beverage according to the invention with added calcium.

(2) FIG. 2 shows the effect of added calcium on sensory texture attribute (thickness) of RTD beverages.

(3) FIG. 3 shows the effect of added calcium on viscosity of RTD beverages.

DETAILED DESCRIPTION OF THE INVENTION

(4) 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.

(5) 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.

(6) 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.

(7) 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 5-30 microns as measured by D(4,3) mean diameter. The agglomerate particle size distribution (PSD) is measured using a laser particle size analyser such as a Mastersizer 3000 (Malvern Instruments, UK). For the measurements a sample may e.g. be dispersed in the Hydro SM measuring cell until an obscuration rate of 9-10% is obtained and then analysed in the Mastersizer.

(8) 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 9720 BNWP Ionplus® Sure-Flow® calcium ion selective electrode (ISE) (Thermo Scientific, Chelmsford, Mass., USA). The electrode connected to a Thermo Scientific Orion Star A214 pH/ISE meter (Thermo Scientific, Chelmsford, Mass., USA) with a waterproof BNC connector. Optimum Results™ A filling solution (Thermo Scientific, Cat. No. 900061) is used to fill the electrode.

(9) 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 %.

(10) In accordance with the invention it is preferred that the divalent cations are selected from the group consisting of Ca, Mg cations or a combination thereof. These divalent cations are food grade and do not provide for easy oxidation.

(11) In a preferred embodiment of the invention the divalent cations are calcium cations.

(12) Advantageously, the divalent cations are added to until the free divalent cations concentration is 3-20 mM and most preferred 4-8 mM divalent cations.

(13) Furthermore, it is preferred that 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.

(14) 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.

(15) According to the invention the method and the product comprises a stabilizing system including but not limited to being selected from the group consisting of gellan gum, guar gum, locust bean gum, acacia gum, pectin or a combination thereof. The most preferred stabilizing system comprises gellan gum. Furthermore, stabilizing system may further comprises 0.05-0.1 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 4° C., 20° C. and 30° C. during a 9 month of storage. Advantageously, the gellan gum is high acyl with a level of acylation of 50-99%.

(16) In a preferred embodiment of the invention the aggregates has a particle size of 5-30 microns, preferably 6-15 microns as D(4,3) mean diameter as measured by laser diffraction. This give a desirable mouth feel to the product without the aggregates providing grittiness.

(17) The product according to the invention may further comprises flavour. Preferred flavours are fruit flavor or cocoa or combination thereof.

(18) The ingredient composition for the method and product according to the invention may comprises from 0-4 wt. % milk fat, preferably 0-3.5 wt. %, more preferably 0-2 wt. %, most preferably 0-1 wt. % of milk fat.

(19) 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.

(20) 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.

(21) In a particular preferred embodiment of the invention the whey protein source is non- or minimally denatured.

(22) The invention also relates to a shelf stable ready-to-drink beverage obtained by a method as described in the invention.

(23) In another aspect of the invention the invention relates to a shelf stable ready-to-drink beverage product comprising aggregated proteins comprising micellar caseins and whey protein aggregates, wherein the product has a pH of 6.6-7.2, 1.5-8.0 wt. % milk proteins, a casein to whey protein ratio of 90/10-60/40, and a concentration of 3-20 mM divalent cations, and the aggregates are of 5-30 microns mean diameter D.sub.(4,3) as measured by laser diffraction. The product preferably has a concentration of divalent cations in the product is 4-8 mm. Further as discussed the divalent cations are selected from divalent cation Ca, Mg or a combination thereof.

(24) 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 0-4 wt. % milk fat, preferably 0-3.5 wt. %, more preferably 0-2 wt. %, most preferably 0-1 wt. % of milk fat.

(25) According to the invention, the product may comprises sucrose, preferably 0-4.5, more preferably 0.5-4.5 wt % sucrose.

EXAMPLES

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

(27) 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.

(28) Fluid milk containing 1% milkfat was used in preparation of all samples described in the examples below.

Example 1

(29) Preparation of Beverages

(30) The RTD beverages are made by the following process: Hydration (e.g., wetting) of cocoa powder in water for 45 minutes at 90° C. to form the cocoa slurry. High acyl gellan gum and/or guar gum was dry blended with sucrose and then were added under high agitation to a separate tank containing fluid milk. Addition under agitation of the cocoa slurry to the fluid milk tank containing hydrocolloids Addition under agitation of the rest of ingredients such as sweetener, other flavors, and source of divalent cations Homogenization at 135/35 bars at 70° C. Subjection of the beverage to ultra-high temperature (UHT) heat treatment at about 142° C. for about 11 seconds Cooling below 25° C. under aseptic conditions Aseptic filling of the RTD beverage into a suitable aseptic container, e.g. PET bottles, Tetra Pak®, jars, jugs or pouches.

Example 2

(31) The RTD beverage was prepared as in Example 1 process, using 44 kg of skim milk, 3.5 kg of milk cream, 2.5 kg of whey milk powders, 30 g of high acyl gellan gum, 90 g of guar gum, 5 kg sugar, 1 kg of cocoa, 150 g of calcium lactate pentahydrate and water necessary to reach 100 kg of the final beverage.

(32) Particle size distribution determined by using a laser light scattering Mastersizer 3000 MA (Malvern Instrument) equipped with Hydro 2000G dispersion unit is shown in FIG. 1 in comparison between milk produced without added calcium source and invention produced with calcium. The FIG. 1 shows protein aggregation in the invention produced with calcium.

(33) 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 0.5) having normalized sensory texture attribute ˜ of 1.1 (FIG. 2). The invention beverage also had homogeneous visual appearance.

Example 3

(34) The RTD beverage with controlled protein aggregation was prepared as in Example 2, but using 250 g of calcium lactate pentahydrate.

(35) 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 1 (FIG. 2). The invention beverage also had homogeneous visual appearance.

Example 4

(36) The RTD beverage with controlled protein aggregation was prepared as in Example 2, but using 500 g of calcium lactate pentahydrate.

(37) 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 0.9 (FIG. 2). The invention beverage also had homogeneous visual appearance.

Example 5

(38) The RTD beverage with controlled protein aggregation was prepared as in Example 2, but using 650 g of calcium lactate pentahydrate.

(39) 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 0.5 (FIG. 2). However, phase separation and gelation was found during the storage.

Example 6

(40) Viscosities of beverages with addition of 150, 250, 500 and 650 g of calcium lactate pentahydrate are shown in FIG. 3. Viscosity of the all above beverages were significantly higher than that of the reference prepared without addition of calcium lactate pentahydrate.

(41) Viscosities of beverages with 150 and 250 g 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 650 g and above creates physical instability.

Example 7

(42) The RTD beverage with controlled protein aggregation was prepared as in Example 2, but without addition of high acyl gellan gum.

(43) 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.

Example 8

(44) The RTD beverage with controlled protein aggregation was prepared as in Example 2, but with addition of 20 g of high acyl gellan gum and without guar gum.

(45) 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.

Example 9

(46) The RTD beverage with controlled protein aggregation was prepared as in Example 2, with 25 g of high acyl gellan gum and without guar gum.

(47) 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 0.7. The invention beverage also had homogeneous visual appearance.

Example 10

(48) The RTD beverage with controlled protein aggregation was prepared as in Example 2, with 30 g of high acyl gellan gum and without guar gum.

(49) 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 1.4. The invention beverage also had homogeneous visual appearance.

Example 11

(50) The RTD beverage with controlled protein aggregation was prepared as in Example 2, with 33 g of high acyl gellan gum and without guar gum.

(51) 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 1.6. The invention beverage also had homogeneous visual appearance.

Example 12

(52) The RTD beverage with controlled protein aggregation was prepared as in Example 10, with 50 g of calcium lactate pentahydrate.

(53) 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.

Example 13

(54) The RTD beverage with controlled protein aggregation was prepared as in Example 10, with 100 g of calcium lactate pentahydrate.

(55) 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 1.1. The invention beverage also had homogeneous visual appearance.

Example 14

(56) The RTD beverage with controlled protein aggregation was prepared as in Example 11, with 100 g of calcium lactate pentahydrate.

(57) 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 1.4. The invention beverage also had homogeneous visual appearance.

(58) 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.