FROZEN CONFECTION MANUFACTURE

Abstract

Disclosed is a process for manufacturing a premix for a frozen confection, the process comprising the steps of: (i) forming an oil-in-water emulsion comprising fat in an amount of at least 45% by weight of the emulsion; (ii) providing an adjunct composition comprising saccharides, non-saccharide sweetener, protein or a combination thereof; (iii) providing an aqueous liquid; and (iv) combining the emulsion, adjunct composition and aqueous liquid.

Claims

1. A process for manufacturing a premix for a frozen confection, the process comprising the steps of: (i) forming an oil-in-water emulsion comprising fat in an amount of at least 45% by weight of the emulsion, preferably from 48 to 87%, wherein the fat droplets in the emulsion have an average particle size (D.sub.3,2) of less than 1 micron; (ii) providing an adjunct composition comprising saccharides, non-saccharide sweetener, protein or a combination thereof; (iii) providing an aqueous liquid, preferably water; and (iv) combining the emulsion, adjunct composition and aqueous liquid.

2. The process as claimed in claim 1 wherein the emulsion comprises from 50 to 70% fat by weight of the emulsion, preferably from 53 to 65%.

3. The process as claimed in claim 1 wherein the fat droplets in the emulsion have an average particle size (D.sub.3,2) of from 0.1 to 0.7 micron.

4. The process as claimed in claim 1 wherein the emulsion comprises caseinate, preferably sodium caseinate.

5. The process as claimed in claim 1 wherein the emulsion is substantially free from whey protein, preferably comprises less than 0.1% whey protein by weight of the emulsion.

6. The process as claimed in claim 1 wherein step (i) comprises homogenisation with a Controlled Deformation Dynamic Mixer and/or a Cavity Transfer Mixer, preferably a Controlled Deformation Dynamic Mixer.

7. The process as claimed in claim 1 wherein the adjunct composition is powder.

8. The process as claimed in claim 7 wherein the adjunct composition is powder and the powder and emulsion are combined in a granulation step wherein the emulsion is used to bind the powder into granules.

9. The process as claimed in claim 8 wherein step (iv) comprises dispersing and/or dissolving the granules in the aqueous liquid.

10. The process as claimed in claim 7 wherein the powder is in the form of granules.

11. A process for manufacturing a frozen confection comprising manufacturing a premix according to the process of claim 1 and then freezing and optionally aerating the premix.

12. A concentrate for making a premix for a frozen confection, wherein the concentrate is in the form of granules and comprises: a) saccharides and/or non-saccharide sweeteners in a total amount of from to 90% by weight of the concentrate; b) protein in an amount of from 1 to 15% by weight of the concentrate; and c) fat in an amount of from 1 to 25% by weight of the concentrate; or a) saccharides and/or non-saccharide sweetener in a total amount of from 70 to 95% by weight of the concentrate; and b) fat in an amount of from 3 to 25% by weight of the concentrate; or a) protein in an amount of from 10 to 50% by weight of the concentrate; and b) fat in an amount of from 3 to 25% by weight of the concentrate; wherein the fat comprises emulsified fat droplets wherein the fat droplets have an average particle size (D.sub.3,2) of less than 1 micron.

13. The concentrate as claimed in claim 12 wherein the granules have a bulk density of less than 1000 kg m.sup.−3, preferably in the range 600 to 900 kg m.sup.−3.

14. The concentrate as claimed in claim 12 wherein the granules have an average particle size (D.sub.50) of at least 300 microns, preferably in the range 400 micron to 4 mm.

15. The concentrate as claimed in claim 12 wherein the fat droplets are not uniformly distributed within the granules, but are located in discrete regions within the granules.

16. The concentrate as claimed in claim 12 wherein the fat droplets have an average particle size (D.sub.3,2) of from 0.1 to 0.7 micron.

17. The concentrate as claimed in claim 12 wherein the granules are obtainable by a process comprising the steps of: I. forming an oil-in-water emulsion comprising fat in an amount of at least 45% by weight of the emulsion, preferably from 48 to 87%; II. providing powder comprising the saccharides, non-saccharide sweetener and/or protein; III. binding the powder with the emulsion to form agglomerates; and IV. drying the agglomerates.

Description

DETAILED DESCRIPTION

[0061] The present invention will now be described, by way of example only, with reference to the figures, wherein:

[0062] FIG. 1 shows a flow diagram for frozen confection manufacture according to one embodiment of the invention.

[0063] FIG. 2 is a flow a flow diagram for frozen confection manufacture according to a further embodiment of the invention.

[0064] FIG. 3 is a flow a flow diagram for frozen confection manufacture according to a still further embodiment of the invention.

[0065] FIG. 4 shows a scanning electron micrograph of granulated ice cream premix concentrate according to an embodiment of the invention at a magnification of (a)×1000 and (b)×4000.

[0066] FIG. 5 shows a micro-CT image of a granule of ice cream premix concentrate in (a) perspective view and (b) cross-section.

[0067] Referring to FIG. 1, in one embodiment of the invention an ice cream manufacturing process begins with forming a mixture of fat, water and emulsifier. For example desired amounts of coconut fat, water and sodium caseinate are weighed into a mix tank to form a mix of 55 wt % coconut fat, 3.9 wt % sodium caseinate and 41.1 wt % water. The mix may be gently heated in the tank to melt the fat. Preferably the fat is melted and added as a liquid to the mix tank.

[0068] The resulting mixture is then fed through an homogenizer in the same manner as for a conventional premix to produce a concentrated oil-in-water emulsion wherein the fat droplets have an average particle size below 1 micron. Owing to the high fat content of the emulsion, the present inventors have found that small particle sizes may be achieved even if lower homogenization pressures are used than in conventional premix manufacture.

[0069] The concentrated emulsion may also be optionally pasteurized or sterilized at this point which, for example, gives more flexibility in the manufacturing process as the emulsion can be stored until needed or even transported to a remote location for further processing.

[0070] In the next step of the process shown in FIG. 1 the concentrated emulsion is combined with water and powdered ice cream ingredients (for example sugars, stabilizer, skimmed milk powder and emulsifier) in a mix tank. The powders could be pre-blended before adding to the mix tank or added individually. Similarly some powders could be pre-dissolved/dispersed in the water prior to adding to the mix tank.

[0071] The full premix can then optionally be pasteurized. An additional or alternative step is ageing the premix at temperatures between 0 and 10° C. in order to promote fat crystallization which helps in aerating the mix in subsequent steps.

[0072] The next step shown in FIG. 1 is freezing & aerating the premix which can conveniently be achieved simultaneously in a scraped surface heat-exchanger, to produce the ice cream. Finally the frozen and aerated ice cream is optionally hardened, for example by blast-freezing at a temperature below −20° C., and is then ready for storage and/or distribution.

[0073] Referring now to FIG. 2, another embodiment of an ice cream manufacturing process according to the invention is shown. The difference between this embodiment and the one shown in FIG. 1 is that the powder ingredients are first granulated before combining with the emulsion and water to form the premix.

[0074] Granulation can be achieved, for example, by agglomerating the powders with an aqueous liquid binder which is shown in FIG. 2 as water but which could equally be an aqueous solution of one of the powder components (for example aqueous sugar solution). Granulation equipment is widely available and preferred types include, for example, ploughshare mixers, Nauta mixers, screw extruders and the like.

[0075] The advantages of the process shown in FIG. 2 over that in FIG. 1 include that the powder can be shipped to a remote location in the form of granules which simply need dissolving/dispersing at the remote location without any need for handling and blending multiple powders. Furthermore shipping the powder ingredients as performed granules avoids any issues of powder separation which may be encountered if powders were simply blended prior to shipping. Furthermore the present inventors have found that granules are much easier to disperse and/or dissolve than conventional spray-dried powders and so reduce the requirements for powerful mixing equipment at the location where the powder is combined with the emulsion.

[0076] Referring now to FIG. 3, an especially preferred embodiment of an ice cream manufacturing process according to the invention is shown. The difference between this embodiment and the one shown in FIG. 2 is that the powder ingredients are granulated using the emulsion as binder.

[0077] The advantages of the process shown in FIG. 3 over that in FIG. 2 include that the granules are much more storage stable than a liquid emulsion and so can be stored for longer and/or transported for longer distances. Furthermore, as shown in FIG. 3, formation of the premix requires simply combining the granules with water to disperse/dissolve the granules. Surprisingly the present inventors have found that granules wherein the emulsion is used as binder can form ice cream premixes of good quality without the use of complex mixing equipment. Without being bound by theory the inventors believe this may be due to the presence of the fat as discrete droplets within the powder or at least the localization of such droplets in discrete regions within the granules.

[0078] Although the invention has been described with reference to specific embodiments, various modifications of the described modes for carrying out the invention which are apparent to those skilled in the relevant fields are intended to be within the scope of the following claims.

[0079] Except in the examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use may optionally be understood as modified by the word “about”.

[0080] All amounts are by weight unless otherwise specified.

[0081] It should be noted that in specifying any range of values, any particular upper value can be associated with any particular lower value.

[0082] For the avoidance of doubt, the word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of”. In other words, the listed steps or options need not be exhaustive.

[0083] The disclosure of the invention as found herein is to be considered to cover all embodiments as found in the claims as being multiply dependent upon each other irrespective of the fact that claims may be found without multiple dependency or redundancy.

[0084] Where a feature is disclosed with respect to a particular aspect of the invention (for example a concentrate of the invention), such disclosure is also to be considered to apply to any other aspect of the invention (for example a method of the invention) mutatis mutandis.

EXAMPLES

Example 1

[0085] This example demonstrates production of ice cream using a process according to the embodiment shown in FIG. 1.

[0086] An oil-in-water emulsion containing 55 wt % coconut fat (Cargill), 3.85 wt % sodium caseinate (Frieslandcampina) and 41.15 wt % water was prepared as follows: Hot water at 82° C. was added to a mix vessel, followed by the sodium caseinate. The contents of the vessel were vigorously mixed for 5-7 minutes to ensure complete dispersion/dissolution of sodium caseinate. The pre-melted fat/oil was then metered into the vessel and the mixture was agitated at high speeds for further 10 minutes. The mixing operation typically took around 20 minutes. The resulting coarse emulsion was then pumped through a two stage homogenizer (Tetra Alex S05 A supplied by Tetra Pak) at a pressures of 175 bar and 30 bar in the 1st and 2nd stages respectively. The homogenized emulsion was then stored in the storage vessel before metering into the main mixing vessel.

[0087] The ingredients shown in Table 1 were then blended into a single powder:

TABLE-US-00001 TABLE 1 Amount (% by weight Ingredient of total powder blend) Mono-diglyceride emulsifiers 1.2 Stabilizers (Locust Bean Gum, 0.65 Guar Gum + Carrageenan) Skimmed Milk Powder 23 Whey Protein Concentrate 6.1 Maltodextrin and Glucose Syrup 31 Sucrose Balance

[0088] This powder was then dispersed/dissolved in the emulsion and extra water in the main mixing vessel in the following proportions (by weight): 55 parts water, 32 parts powder blend and 13% parts emulsion. The mean droplet size (D.sub.3,2) of the emulsion was 0.3 μm which remained unchanged after mixing with rest of the ingredients.

[0089] The resulting premix was then pasteurized, cooled, frozen and aerated in a scraped surface heat exchanger (ice cream freezer) before hardening and frozen storage.

[0090] The sensorial properties (as assessed by a trained panel of 18 people) of the ice cream made via this procedure were similar to a control ice cream with identical composition but prepared in the conventional manner whereby the whole premix is homogenized. The meltdown properties of this and the control ice cream were also found to be very similar.

Example 2

[0091] This example demonstrates formation of a concentrate in the form of granules wherein an emulsion was used as binder.

[0092] The emulsion for granulation was prepared by the method described above in Example 1 except that the composition of the emulsion was 60 wt % coconut fat, 4.2 wt % sodium caseinate and 35.8 wt % water. This emulsion was used as a binder to produce granules. The composition of the powder blend that was granulated is the same as shown in Table 1 above.

[0093] The granulation was performed using an 80 L ploughshare mixer without chopper/refiner. 50 kg of powder the blend was first mixed for 3 minutes in the mixer to obtain a uniform composition. The binder (emulsion) was then added at the rate of 0.82 kg/min. The binder addition was stopped at regular intervals while continuing mixing to promote homogenous distribution of emulsion/binder in the powder. In this particular example the granulation process was stopped after the addition of 11 kg of emulsion. The total binder loading in the granules was about 18% by total weight of the granules. The wet granules were then dried in a fluid bed dryer at 65° C. such that the final moisture content in the granulated concentrate was less than 3 wt %.

[0094] The bulk density of these granules was determined to be 752 kg/m.sup.3.

[0095] The particle size distribution as determined by sieve analysis is given in Table 2.

TABLE-US-00002 TABLE 2 Sieve Size (mm) Amount Retained (wt %) 2.36 30.76 1.40 24.35 1.00 15.97 0.710 16.88 0.425 9.77 0.25 1.64 0.125 0.63 Receiving Pan 0.00

[0096] From this data it can be seen that the average particle size (D.sub.50) was about 1.2 mm.

[0097] To prepare ice cream from these granules, firstly hot water at 82° C. was introduced in an ice cream mix preparation vessel. The granules were then added at gentle mixing conditions to obtain 40 wt % total solid in water. The mixing was continued for 15 minutes. Vanilla flavor was added 5 minutes before completing the mixing process. The mix was then pasteurized, cooled, frozen and aerated and then hardened in the conventional manner. The mean droplet size, D.sub.3,2, of the fat in the premix prior to freezing was <0.5 μm. The melt down and sensorial properties of the ice cream was of acceptable quality in comparison to ice cream made via the conventional route.

[0098] FIG. 4 shows scanning electron micrographs of the granulated concentrate.

[0099] The electron micrographs were obtained as follows:

[0100] Samples of the concentrates were rapidly mixed with a small volume of diluted mountant (1 part OCT, 3 parts deionised water) to give a thick suspension. This was mounted in to a 5 mm drilled depression in a 10 mm diameter Aluminium stub and immediately plunged in to liquid nitrogen to minimise any dilution at the periphery of the powder particles. Rapid freezing of the diluted mountant created very small ice crystals which were used to assist in differentiating mountant from the granules.

[0101] Frozen samples were transferred to a Gatan Alto 2500 low temperature preparation chamber and heated to −90° C., fractured, etched for 30 seconds and cooled to −110° C. After sputter coating to give a 2 nm Pt layer, samples were transferred to a Jeol 7600 field emission scanning electron microscope fitted with a Gatan cold stage at −130° C. for examination. Imaging parameters include 5 kV accelerating voltage and approximately 60 pA probe current. Secondary electron imaging used low magnification and SEI high resolution modes at working distances of approximately 20 mm or 10 mm.

[0102] As shown in FIG. 4, owing the large particle size, even at a low magnification of ×1000 (FIG. 4 (a)) the borders of the granule particles are not visible. Instead within the particle can be seen discrete regions (1) containing fat droplets (2) separated by discrete regions (3) of non-fat components. The length scale of the regions (1) can be seen in FIG. 5(a) to be a few tens of microns.

[0103] FIG. 5 shows the results of X-ray microtomography of a representative granule from the concentrate. The micro-computed tomography (or micro CT) was conducted as follows:

[0104] Samples in plastic cylindrical sample holders with an inner diameter of 3.3 mm were imaged using a Skyscan 1172 desktop micro-CT system. Power settings of 59 kV and 167 pA were used. Images were acquired using a step size of 0.20° over 360 degrees and frame averaging of 3. Scans with pixel sizes of 1.0 μm were made. For 3D visualisation and quantitative analysis the AvizoFire 8.1.1 software of Visualization Sciences Group, Inc was used. The different phases were identified using thresholding.

[0105] FIG. 5(a) shows the whole granule while FIG. 5b shows the granule in section through a plane (10). The plane (10) has a width of 2.7 mm and a height of 2.2 mm as shown in FIG. 5 (b). It is clear from FIG. 5(b) that the granule comprises discrete fat-containing regions (1), separated by discrete regions (3) of non-fat components. Also visible in FIG. 5(b) are gas cells (4) which form pores in the granule.

Example 3

[0106] This example demonstrates formation of a concentrated oil-in water emulsion suitable for use in the invention wherein the emulsion is formed with a rotor-stator homogenizer.

[0107] In this example whey protein concentrate (Textrion Progel™ 800 ex DMV) was used as surface active protein to emulsify the fat. The composition of the high fat emulsion is shown in Table 3.

TABLE-US-00003 TABLE 3 Ingredient % by weight of emulsion Sunflower oil 52 Whey protein concentrate 9 Sucrose 19 Water 20

[0108] The emulsion was made using an IKA LaborPilot™ 2000/4 colloid mill (IKA-Werke GmbH & co. KG, Staufen, Germany). The mill is rpm controlled and provides integrated measurement of the exit temperature, pressure drop and powder input. The emulsification was performed with a smooth milling head at a minimal gap of 0.1 mm and at 10,000 rpm. The mill head is jacketed for active cooling with cold water.

[0109] A pre-emulsion was prepared in 2 kg batches in a 5 litre vessel equipped with six-blade impeller with blade angle of 45°. The protein solution was prepared first by adding powder gradually to lukewarm water. The protein was then immediately followed by gradual oil addition. The sucrose was added after the oil. The pre-emulsion was fed to the mill using a mono pump. The resultant emulsion from the discharge end was collected in a suitable container for characterization. The droplet size (D.sub.3,2) of this emulsion was 0.39 μm.

[0110] A second emulsion with the composition shown in Table 4 was prepared in a similar manner but with the mill operating at 8500 rpm.

TABLE-US-00004 TABLE 4 Ingredient % by weight of emulsion Sunflower oil 63 Whey protein concentrate 12 Sucrose 0 Water 25

[0111] The resultant emulsion droplet size (D.sub.3,2) was 0.68 μm.

Example 4

[0112] This example demonstrates formation of a concentrated oil-in water emulsion suitable for use in the invention wherein the emulsion is homogenized with a CDDM.

[0113] An aqueous phase, an oil phase and an emulsion were prepared and the said oil phase and emulsion were then combined to form a HIPE as set out below. The composition of the HIPE is shown in Table 5.

TABLE-US-00005 TABLE 5 Ingredient % by weight of emulsion Coconut oil 76 Mono-di glyceride 3 Sodium Caseinate 3 Water 18

[0114] The aqueous and oil phases and emulsion were prepared according to the following method: [0115] 1.1 A 2 litre steel container was placed on a hot plate into which 0.425 kg of boiling water was introduced. 75 grams sodium caseinate was added slowly to the boiling water while stirring with an IKA ULTRA-TURRAX T18 with a S 18 N-19 G Dispensing element. Stirring was continued until visually the sodium caseinate was judged to be in solution. The temperature of the resultant aqueous phase was held at ˜80° C. [0116] 1.2 2880 grams of coconut oil was slowly melted in a 5 litre vessel. The coconut oil temperature was raised to ˜90° C. 120 g of Mono-di glyceride (HP60) was added to the molten oil. The mixture was stirred by hand until the HP60 dissolved to form a transparent solution. The temperature of the resultant oil phase was held at ˜80° C. [0117] 1.3 1.17 kg of the oil phase prepared according to 1.2 was transferred into the steel container over a period of 10 minutes while stirring with an IKA EUROSTAR overhead stirrer fitted with a Jiffy Mixer [HS-1] O.D. 67 mm. Stirring speed was maintained at 1000 rpm to produce a concentrated oil-in-water emulsion. Stirring was continued for a further 10 minutes throughout which the temperature of the resultant oil-in-water emulsion was held at −80° C.

[0118] The oil phase and emulsion prepared according to 1.2 and 1.3, respectively, were combined and mixed in the appropriate proportion to form the HIPE of Table 5 via a continuous mixing assembly comprising the following: [0119] 2.1 Two hoppers, the first hopper (1 litre capacity) containing the oil phase from 1.2 and the second hopper (5 litre capacity) containing the emulsion from 1.3. [0120] 2.2 Two progressive cavity pumps [Supplier=Mono Pumps, Spec. No.=LF052], the first being gravity fed from the first (oil phase) hopper and the second being gravity fed from the second (emulsion pre-mix) hopper. [0121] 2.3 A gear pump [Supplier=Pump Solutions Group, Spec. No=MARG CINO CX22/13], which is attached to the outlets of each of the progressive cavity pumps by pipework configured as a “T” piece, which enables the output streams from each of the two progressive cavity pumps to be combined into a single feed stream to the inlet of said gear pump. [0122] 2.4 A CDDM [Supplier=Maelstrom Advanced Process Technologies Limited, Spec. No.=MaPP Benchtop System mk 1.0] attached at the inlet to the outlet of said gear pump, and from the outlet of which a HIPE is discharged.

[0123] The resulting HIPE had a droplet size D.sub.3,2 of 0.57 μm.

Example 4

[0124] This example demonstrates two granule compositions which can be used in various propositions to make a variety of frozen confection mixes.

[0125] The granules were made in a similar manner as described in Example 2 but with the powder ingredients being either saccharides (Sample A) or dairy powders (Sample B). The final composition of the granules is shown in Tables 6 and 7.

TABLE-US-00006 TABLE 6 Ingredient % by weight of Sample A Maltodextrin 17-20DE 12.5 Glucose Syrup Solids 40DE 23.3 Sucrose Balance Coconut Oil (Emulsified) 15.4

TABLE-US-00007 TABLE 7 Ingredient % by weight of Sample B Skimmed Milk Powder Balance Whey Powder 17.0 Coconut Oil (Emulsified) 15.4

[0126] The two samples of granules can, for example, be combined in a weight ratio of 2.4 to 1 (Sample A to Sample B) and dissolved together in water to a total solids level of around 40%. The resulting mix provides good quality ice cream on freezing and aeration.