Frozen confection, premix, and processes for the preparation thereof

Abstract

The present invention relates to a process for preparing a frozen confection premix comprising the steps of: (a) admixing a protein composition comprising plant protein and water with a bioconversion agent comprising active enzyme(s), and incubating under non-fermentation conditions to provide a bioconverted protein composition; (b) combining additional frozen confection ingredients with the bioconverted protein composition of step (a) to provide a mixture, wherein the additional frozen confection ingredients comprise fat and sugars; (c) homogenising the mixture of step (b) to provide the frozen confection premix; wherein the enzyme(s) are inactivated after step (a), after step (b), or after step (c), and wherein the incubation under non-fermentation conditions is at a temperature of 1 to 25°C for 10 to 50 minutes. The present invention also relates to a frozen confection premix or frozen comprising: fat in an amount of 1 to 15 wt%; sugars in an amount of 10 to 30 wt%; bioconverted plant protein in an amount of 0.4 to 4 wt%; and bioconversion agent in an amount of 0.05 to 0.5 wt%, wherein the bioconversion agent comprises inactive enzyme(s). The frozen confection premix can be frozen to provide a frozen confection.

Description

[0001] FROZEN CONFECTION, PREMIX, AND PROCESSES

[0002] FOR THE PREPARATION THEREOF

[0003] Field of the invention

[0004] The invention relates to a process for preparing a frozen confection premix, and to the premix and frozen confection obtainable from this process. In particular, the invention relates to a process for preparing a premix for a plant-based frozen confection, wherein the resulting frozen confection has improved sensorial properties.

[0005] Background of the invention

[0006] Plant-based foods are a growing consumer trend, which is thought to be driven by increasing health and environmental consciousness. As a result, there is currently an increased consumer demand for frozen confections which are not based on dairy ingredients, and instead use plant-based alternatives.

[0007] Frozen confections where some or all of the dairy ingredients have been replaced with plant-based ingredients are commercially available. For instance, pulse protein (such as soy protein or pea protein) is becoming more widely used in frozen confections.

[0008] The molecular structures of plant proteins are very different from those of dairy proteins, and a number of technical challenges may occur when formulating plant-based frozen confections. One such challenge relates to texture and mouthfeel, since milk proteins stabilise the partial coalescence of the fat phase and maintain small air bubbles in frozen confections. In particular, it is difficult to produce whipped textures using plant-based proteins.

[0009] Furthermore, the flavour and texture of frozen confections formulated with certain plant proteins is still unappealing to some consumers. In particular, their widespread acceptance is hindered by issues around their taste, since plant proteins tend to have an inherent taste that formulators must mask in order to create a neutral product base, for example, pulse proteins tend to have “beany” off-notes. In addition, consumers want frozen confections that are dairy-free, but with the creamy mouthfeel and texture of regular ice cream. Therefore, there remains a need to overcome one or more of the drawbacks associated with the current formulations. In particular, it would be advantageous to mitigate the off- flavour of plant proteins (such as pulse proteins) in order to provide plant-based frozen confections which are more appealing to consumers.

[0010] Summary of the invention

[0011] In a first aspect, the present invention relates to a process for preparing a frozen confection premix comprising the steps of:

[0012] (a) admixing a protein composition comprising plant protein and water with a bioconversion agent comprising active enzyme(s), and incubating under nonfermentation conditions to provide a bioconverted protein composition;

[0013] (b) combining additional frozen confection ingredients with the bioconverted protein composition of step (a) to provide a mixture, wherein the additional frozen confection ingredients comprise fat and sugars;

[0014] (c) homogenising the mixture of step (b) to provide the frozen confection premix, wherein the frozen confection premix is an oil-in water emulsion; wherein the enzyme(s) are inactivated after step (a), after step (b), or after step (c), and wherein the incubation under non-fermentation conditions is at a temperature of 1 to 25°C for 10 to 50 minutes.

[0015] In a second aspect, the present invention relates to a process for preparing a frozen confection, wherein the process comprises preparing a frozen confection premix by the process of the first aspect, and then subsequently freezing the frozen confection premix to provide the frozen confection.

[0016] In a third aspect, the present invention provides a frozen confection premix or frozen confection comprising:

[0017] • fat in an amount of 1 to 15 wt%;

[0018] • sugars in an amount of 10 to 30 wt%;

[0019] • bioconverted plant protein in an amount of 0.4 to 8 wt%; and

[0020] • bioconversion agent in an amount of 0.05 to 0.5 wt%, wherein the bioconversion agent comprises inactive enzyme(s). Detailed description of the invention

[0021] In a first aspect, the present invention relates to a process for preparing a frozen confection premix. The frozen confection premix can be frozen to produce a frozen confection. Indeed, the term “frozen confection premix” would be understood by the skilled person to mean the mixture of frozen confection ingredients that is fed into the freezer to produce a frozen confection. The frozen confection premix is an oil-in-water emulsion (in liquid form).

[0022] Step (a) of the process, comprises admixing a protein composition comprising plant protein and water with a bioconversion agent comprising active enzyme(s), typically active yeast enzyme(s), and incubating under non-fermentation conditions to provide a bioconverted protein composition.

[0023] The protein composition comprises plant protein and water. It is preferred that the pH of the protein composition (at 20°C) is greater than 4, greater than 5, and most preferably from 6 to 8. The protein composition may be a slurry, dispersion or solution, depending on the amount of protein. Dissolution / dispersion of the protein in water can be aided with methods known in the art such as applying shear and / or increasing the temperature (for example to 50°C, 60°C, or 70°C). In order for the bioconversion step to be easily implemented in existing frozen confection production processes, the protein composition is preferably a liquid composition, which comprises a sufficient amount of water to be pourable. Preferably, the protein composition comprises water in an amount of at least 60 wt%, at least 75 wt%, or even at least 90 wt%. In order to avoid a concentration step (which would add complexity and cost to the process), it is preferred that the protein composition comprises water in an amount of no more than 99.6 wt%, such as no more than 99.5 wt%, no more than 99.4 wt%, or even no more than 99 wt%.

[0024] The protein composition may comprise the plant protein in an amount that is suitable for the final frozen confection premix, or it may comprise the plant protein in a higher amount, with the plant protein being diluted at a subsequent point in the process. (As mentioned above, it is preferable to avoid a concentration step, and thus the protein composition will usually not comprise the plant protein in a lower amount than is suitable for the final frozen confection premix). Preferably, the amount of protein in the protein composition is from 0.4 to 40 wt%, 0.5 to 30 wt%, 0.6 to 20 wt%, or even 1 to 10 wt%. The amount of plant protein as used herein refers to the amount of plant protein present in the protein composition (and not to the amount of the proteinaceous ingredient). For example, if a protein composition comprises 1 wt% of a plant protein ingredient, with the plant protein ingredient containing 80 wt% protein, then the protein composition comprises 0.8 wt% of the plant protein.

[0025] The plant protein is preferably a pulse protein, since pulse proteins are known to have inherent taste off notes (such as “beany” off-notes) that formulators seek to mask in order to create a neutral product base. For example, the plant protein is preferably a pulse protein selected from the group consisting of: bean protein (such as fava bean protein), lentil protein, lupin protein, pea protein, soy protein, and mixtures thereof. It is particularly preferred that the pulse protein comprises pea protein, soy protein, or a mixture thereof.

[0026] The bioconversion agent comprises active enzyme(s), such as active yeast enzyme(s). In particular, the bioconversion agent preferably comprises active enzyme(s) selected from alcohol dehydrogenase, aldo-keto reductases, aldehyde oxidase, and mixtures of one or more thereof. As used herein, the term “active enzyme(s)” means that the enzyme(s) are capable of catalysing their usual enzymatic reaction, and the term “yeast enzyme(s)” denotes enzymes that are found in yeast species, particularly in Saccharomyces cerevisiae. The term “bioconversion agent” is used as shorthand for “bioconversion agent comprising active enzyme(s)” and should be interpreted accordingly unless it is explicit that a different meaning is intended.

[0027] The bioconversion agent preferably comprises yeast, particularly Saccharomyces cerevisiae. It is particularly preferred that the bioconversion agent comprises baker’s yeast, which has wide commercial availability. The bioconversion agent can comprise viable yeast. The bioconversion agent can also comprise non-viable yeast, so long it comprises active yeast enzyme(s). The bioconversion agent can also comprise isolated yeast enzyme(s), although this is not typically preferred as it represents a more costly option from an economic standpoint. As such, the bioconversion agent is preferably viable yeast, non-viable yeast, or a mixture thereof, wherein the yeast is preferably of the species Saccharomyces cerevisiae, and the strain known as baker’s yeast is particularly preferred. As used herein, the term “active yeast enzyme(s)” usually refers to enzymes selected from alcohol dehydrogenase, aldo-keto reductases, aldehyde oxidase, and mixtures of one or more thereof. The enzyms(s) are active, i.e. capable of catalysing their usual enzymatic reaction.

[0028] The bioconversion agent is admixed with a protein composition comprising plant protein and water. The ratio of bioconversion agent to protein may be used to describe the amount of bioconversion agent that is admixed with the protein composition. Preferably, the bioconversion agent is admixed with the protein composition such that the ratio of bioconversion agent to plant protein is 1 :5 to 1 :50. For example, the ratio of bioconversion agent to plant protein is preferably 1 :6 to 1 :40, 1 :7 to 1 :25, or even 1 :8 to 1 :20.

[0029] Where the bioconversion agent is viable yeast, the bioconversion agent is preferably admixed in an amount of from 0.5 x 107to 1 x 1010CFU per g of protein, such as 0.5 x 107to 5 x 109CFU per g of protein or even 1 x 107to 1 x 109CFU per g of protein. Colony forming unit (CFU) is a unit which estimates the number of microbial cells (in this instance yeast cells) in a sample that are viable and able to multiply. As such counting with CFUs requires culturing the microbes and counts only viable cells (this is in contrast with microscopic examination which counts all cells, living or dead). Where the bioconversion agent is non-viable yeast, CFU per g of protein is not an appropriate way to describe the amount of bioconversion agent that is admixed with the protein composition.

[0030] The protein composition comprising plant protein and water is admixed with the bioconversion agent, and incubated under non-fermentation conditions to provide a bioconverted protein composition. Surprisingly, the bioconverted protein composition has less off-flavours, including off-flavours that may be described as beany or cardboard while avoiding the negative effects of fermentation.

[0031] Fermentation conditions for yeasts are well known in the art. Fermentation conditions are selected to achieve optimal growth of yeast and the desired production of ethanol, CO2 and / or acids. The optimal growth temperature for yeasts, such as Saccharomyces cerevisiae, is 30 to 35°C. At lower temperatures yeast is generally thought to be almost inactive and can therefore be stored for weeks to months. Acid production can be used as a measure for fermentation (e.g. by measuring a decrease in pH, such as a pH decrease of 2).

[0032] The present invention provides a bioconversion step under non-fermentation conditions which can be described as conditions which avoid fermentation as described above. The incubation under non-fermentation conditions is at a temperature of 1 to 25°C for 10 to 50 minutes. The incubation under non-fermentation conditions is preferably performed at a temperature of at least 1 °C, at least 4°C, at least 7°C, or even at least 10°C. The incubation under non-fermentation conditions is preferably performed at a temperature of no more than 25°C, no more than 24°C, no more than 23°C, no more than 22°C, or even no more than 21 °C. A temperature range of 10 to 25°C is particularly preferred. The duration of the incubation under non-fermentation conditions is preferably at least 10 minutes, at least 15 minutes, or even at least 20 minutes. The duration of the incubation under non-fermentation conditions is no more than 50 minutes, or even no more than 40 minutes. An advantage of the use of these temperatures and incubation times is that the process of the present invention can be implemented in existing frozen confection production processes. For example, the bioconversion step can be performed at the ambient temperature of an ice cream factory.

[0033] Preferably, the non-fermentation conditions are defined as at least one, preferably at least two, more preferably all three of the following conditions:

[0034] (i) the bioconversion step induces a decrease in the pH of the protein composition of less than 1.3, preferably less than 1 , less than 0.7, less than 0.5, or even than 0.3;

[0035] (ii) the temperature during the bioconversion step is no more than 25°C, preferably no more than 24°C, no more than 23°C, no more than 22°C, or even no more than 21 °C, and preferably from 10 to 25°C; and

[0036] (iii) the bioconversion step produces ethanol in an amount of from 0 to 0.4 wt%, from 0 to 0.3 wt%, more preferably from 0 to 0.2 wt% by weight of the protein composition.

[0037] Preferably, the non-fermentation conditions are defined as the combination of conditions (i) and (ii). The bioconverted plant protein typically has less off-flavour than the same plant protein which has not been bioconverted. Additionally or alternatively, the bioconverted plant protein has less off-flavour than the same plant protein which has been fermented for 16 hours at 30°C. For example, the amount of at least three off-flavour markers, preferably selected from: phenylacetaldehyde; 2,3 pentanedione; 3-methyl- acetate- 1 -butanol; hexanoic acid (ethyl ester); ethyl acetate; and octanoic acid (ethyl ester) is reduced in the bioconverted protein composition compared to a fermentation step of 16 hours at 30°C carried out on the same protein composition subjected to the bioconversion step. Preferably, the amount of at least one of, at least two of, or even all three of: phenylacetaldehyde; 2,3 pentanedione; and 3-methyl- acetate-1 -butanol is reduced in the bioconverted protein composition compared to a fermentation step of 16 hours at 30°C carried out on the same protein composition subjected to the bioconversion step. It is particularly preferred that the amount is reduced by at least 4-fold, or even at least 6-fold. Preferably, the amount of at least one of, at least two of, or even all three of: hexanoic acid (ethyl ester); ethyl acetate; and octanoic acid (ethyl ester) is reduced in the bioconverted protein composition compared to a fermentation step of 16 hours at 30°C carried out on the same protein composition subjected to the bioconversion step.

[0038] Step (b) of the process comprises combining additional frozen confection ingredients with the bioconverted protein composition of step (a) to provide a mixture, wherein the additional frozen confection ingredients comprise fat and sugars. The additional frozen confection ingredients may further comprise emulsifier(s), stabilizer(s), flavour(s), and / or colour(s).

[0039] The mixture of step (b) preferably comprises the bioconverted plant protein in an amount of from 0.4 to 8 wt%, and more preferably in an amount of 0.5 to 6 wt%, 0.55 to 5 wt%, 0.6 to 4 wt%. It is particularly preferred that the mixture of step (b) comprises the bioconverted plant protein in an amount of from 0.6 to 2.5 wt%, or even 0.6 wt% to 2 wt%.

[0040] The mixture of step (b) preferably comprises the fat in an amount of 1 to 15 wt%, and more preferably in an amount of 2 wt% to 12 wt%, 3 wt% to 10 wt%, or even from 4 wt% to 8 wt%. The fat is preferably vegetable fat (such as coconut oil, palm oil, palm kernel oil, or a mixture thereof), and it is particularly preferred that the fat is coconut oil. The mixture of step (b) preferably comprises the sugars in an amount of 10 to 30 wt%, and more preferably in an amount of 12 to 28 wt%, 14 to 26 wt%, or even 16 to 24 wt%. As used herein the term “sugars” includes monosaccharides, disaccharides and oligosaccharides (which are formed from 3 to 10 monosaccharide units). Monosaccharides include glucose, fructose, galactose and mannose. Disaccharides include sucrose, lactose and trehalose. Oligosaccharides include raffinose. The term “sugars” does not include polysaccharides, which comprise >10 monosaccharides.

[0041] The additional frozen confection ingredients may further comprise non-nutritive sweetener(s), emulsifier(s), stabilizer(s), flavour(s), and / or colour(s).

[0042] Step (c) of the process comprises homogenising the mixture of step (b) to provide the frozen confection premix. As set out above, the frozen confection premix is an oil-in water emulsion.

[0043] The enzyme(s) are inactivated after step (a), after step (b), or after step (c). Inactivation of the enzyme(s) is preferably achieved by heating to a temperature of at least 60°C, or even at least 70°C. However, in order to avoid cooked flavours, it is preferred that the temperature is less than 100°C, and more preferably less than 95°C, or even less than 90°C. The time needed for enzyme inactivation will depend, amongst other things, on the temperature, with lower temperatures requiring longer durations. Preferably, the time is at least 10 seconds, at least 15 seconds, or even at least 30 seconds. In order to maintain process efficiency, it is preferred that the time is no more than 30 minutes, such as no more than 20 minutes, or even no more than 15 minutes.

[0044] For example, the enzyme(s) may be inactivated by a pasteurisation step, which preferably occurs after step (c). The pasteurisation step may involve heating to at least 65°C, preferably at least 69°C, at least 71 °C, or even at least 74°C for a duration of at least 10 minutes, at least 20 minutes, or even at least 30 minutes. Alternatively, the pasteurisation step may involve heating to at least 78°C, at least 80°C, at least 82°C, or even at least 84°C for a duration of at least 10 seconds, at least 15 seconds, at least 20 seconds, or even at least 25 seconds. The minimum requirements for pasteurisation of frozen confection premixes varies from jurisdiction to jurisdiction, and the skilled person would easily be able to determine the appropriate conditions.

[0045] Alternatively the enzyme(s) may be inactivated after step (a), for example by heating the bioconverted protein composition to 70°C, 80°C, or even 85°C. An advantage of this is that it can be implemented in existing frozen confection production processes, where it is common to add frozen confection ingredients to water which has been heated to such temperatures. Even where a heating step is included after step (a), it is still preferred that a pasteurisation step is included in the process, preferably after step (c).

[0046] The process preferably comprises an additional and subsequent step of ageing the premix. This step is referred to as step (d). Where this step is included, the enzyme(s) are inactivated prior to the ageing step, i.e. prior to step (d). During ageing, the premix is preferably held at a temperature of 0 to 4°C. Ageing of the premix is typically carried out for a duration of anywhere from 4 to 24 hours.

[0047] In a second aspect, the present invention relates to a process for preparing a frozen confection, wherein the process comprises preparing a frozen confection premix by the process of the first aspect, and then subsequently freezing the frozen confection premix to provide the frozen confection.

[0048] It is preferred that the frozen confection premix is aerated during the freezing step to provide a frozen confection having an overrun of from 30 to 150%, such as 40 to 140%, 50 to 130%, 60 to 120%, or even 70 to 110%. Overrun (with unit “%”) is defined by the following equation: volume of aerated product - volume of initial mix overrun = - - - x 100%

[0049] Volume of initial mix

[0050] Overrun is measured at ambient temperature (20°C) and atmospheric pressure.

[0051] In a third aspect, the present invention provides a frozen confection premix or frozen confection comprising:

[0052] • fat in an amount of 1 to 15 wt%; • sugars in an amount of 10 to 30 wt%;

[0053] • bioconverted plant protein in an amount of 0.4 to 8 wt%; and

[0054] • bioconversion agent in an amount of 0.05 to 0.5 wt%, wherein the bioconversion agent comprises inactive enzyme(s).

[0055] The frozen confection is preferably a plant-based frozen confection (resulting from the freezing of a plant-based frozen confection premix). As used herein the term plant-based means that the frozen confection is formulated primarily from plant-derived ingredients. Nevertheless, it will be appreciated that the plant-based frozen confection may be fortified with vitamins and / or minerals or flavoured with ingredients (such as honey) which are not strictly speaking derived from plants. Preferably at least 98% by dry weight of the ingredients are derived from plants, more preferably at least 99%, at least 99.5%, at least 99.9%, most preferably 100% by dry weight of the ingredients are derived from plants. In particular, it is preferred that the frozen confection is essentially free of animal- derived ingredients, and thus comprises animal-derived ingredients in an amount of less than 0.1 wt%, preferably less than 0.05 wt%, more preferably less than 0.01 wt%.

[0056] The frozen confection premix or frozen confection comprises fat in an amount of 1 to 15 wt%, more preferably in an amount of 2 wt% to 12 wt%, 3 wt% to 10 wt%, or even from 4 wt% to 8 wt%. The fat is preferably vegetable fat (such as coconut oil, palm oil, palm kernel oil, or a mixture thereof), and it is particularly preferred that the fat is coconut oil.

[0057] The frozen confection premix or frozen confection comprises sugars in an amount of 10 to 30 wt%. Sugars are used in almost all types of frozen confection and have two major functions: delivering sweetness and controlling the amount of ice. As used herein the term “sugars” includes monosaccharides, disaccharides and oligosaccharides (which are formed from 3 to 10 monosaccharide units). Monosaccharides include glucose, fructose, galactose and mannose. Disaccharides include sucrose, lactose and trehalose. Oligosaccharides include raffinose. The term “sugars” does not include polysaccharides, which comprise >10 monosaccharides. Some ingredients commonly included in frozen confections may contribute to the amount of sugars. An example is corn syrup (sometimes called glucose syrup) - which is a mixture of monosaccharides, disaccharides and oligosaccharides.

[0058] High concentrations of sugars may contribute unwanted sweetness and or calories to the frozen confection. Therefore, the amount of sugars in the frozen confection premix or frozen confection is no more than 30 wt%, preferably no more than 28 wt%, no more than 26 wt%, or no more than 24 wt%. Conversely, low concentrations of sugars may be inappropriate if the frozen confection is a scoopable product, since a low concentration of sugars tend to result in frozen confections with a high ice content. Therefore, the amount of sugars in the frozen confection premix or frozen confection is at least 10 wt%, preferably at least 12 wt%, at least 14 wt%, or at least 16 wt%.

[0059] The frozen confection premix or frozen confection comprises bioconverted plant protein in an amount of 0.4 to 2.5 wt%, and more preferably in an amount of 0.5 to 2.5 wt%, 0.55 to 2.5 wt%, 0.6 to 2.5 wt%. It is particularly preferred that the frozen confection premix or frozen confection comprises the bioconverted plant protein in an amount of from 0.6 to 2.5 wt%, 0.6 wt% to 2 wt%, or even 0.5 wt% to 2 wt%.

[0060] The frozen confection premix or frozen confection comprises bioconversion agent in an amount of 0.05 to 0.5 wt%. The frozen confection premix or frozen confection comprises the bioconversion agent in an amount of at least 0.05 wt%, preferably at least 0.1 wt%. The frozen confection premix or frozen confection comprises the bioconversion agent in an amount of no more than 0.5 wt%, preferably no more than 0.4 wt%. The bioconversion agent is preferably yeast, more preferably Saccharomyces cerevisiae. It is particularly preferred that the bioconversion agent is baker’s yeast, which has wide commercial availability. The presence of yeast can be confirmed by microscopy. The inventors have found that incorporation of a bioconversion agent comprising active enzyme(s) into a frozen confection results in unwanted off-flavours (particularly yeast off- flavours), thus the bioconversion agent comprises inactive enzyme(s).

[0061] The enzyme(s) may be inactivated e.g. by heating the bioconverted protein composition to 70°C, 80°C, or even 85°C. An advantage of this is that it can be implemented in existing frozen confection production processes, where it is common to add frozen confection ingredients to water which has been heated to such temperatures. Additionally or alternatively, the enzyme(s) may be inactivated by a pasteurisation step. The pasteurisation step may involve heating to at least 65°C, preferably at least 69°C, at least 71 °C, or even at least 74°C for a duration of at least 10 minutes, at least 20 minutes, or even at least 30 minutes. Alternatively, the pasteurisation step may involve heating to at least 78°C, at least 80°C, at least 82°C, or even at least 84°C for a duration of at least 10 seconds, at least 15 seconds, at least 20 seconds, or even at least 25 seconds. The minimum requirements for pasteurisation of frozen confection premixes varies from jurisdiction to jurisdiction, and the skilled person would easily be able to determine the appropriate conditions.

[0062] The frozen confection premix or frozen confection may additionally comprise at least one stabilizer, which is preferably selected from the group consisting of locust bean gum, xanthan gum, guar gum, carrageenan, tara gum, and mixtures thereof (for example, a mixture of locust bean gum and guar gum). The amount of stabilizer in the frozen confection premix or frozen confection is preferably 0.1 wt% to 1 wt%, 0.15 wt% to 0.8 wt%, or 0.2 wt% to 0.5 wt%.

[0063] The frozen confection premix or frozen confection may additionally comprise an emulsifier or a mixture of emulsifiers (such as mono-diglycerides and the like). For example, the frozen confection may comprise emulsifier in an amount of 0.05 wt% to 1 wt%, 0.1 wt% to 0.8 wt%, or 0.2 wt% to 0.5 wt%.

[0064] The frozen confection premix or frozen confection preferably comprises ethanol in an amount of 0 to 0.4 wt%, from 0 to 0.3 wt%, or even from 0 to 0.2 wt%.

[0065] The frozen confection may optionally comprise non-nutritive sweetener, such as aspartame, acesulfame K, erythritol, sucralose, or one or more steviol glycosides such as rebaudioside A. Mixtures of two or more non-nutritive sweeteners may also be used.

[0066] The frozen confection may optionally comprise colours and / or flavours. In a particularly preferred embodiment, the frozen confection premix or frozen confection comprises:

[0067] • fat in an amount of 3 to 10 wt%;

[0068] • sugars in an amount of 15 to 25 wt%;

[0069] • bioconverted plant protein in an amount of 0.5 to 2 wt%;

[0070] • bioconversion agent in an amount of 0.05 to 0.25 wt%, wherein the bioconversion agent comprises inactive enzyme(s).

[0071] Numerical ranges expressed in the format “from x to y” are understood to include x and y, and in specifying any range of values or amounts, any particular upper value or amount can be associated with any particular lower value or amount. Unless otherwise specified, wt% refers to weight percent based on the weight of the entire formulation (including water).

[0072] 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.

[0073] Figures

[0074] By way of example, the present invention is illustrated with reference to the following figures, in which:

[0075] Figure 1 is a plot of the sensory data from Example 3;

[0076] Figures 2a and 2b show photos of API® ZYM strips for viable yeast and irradiated yeast, respectively (from Example 5);

[0077] Figure 3 is a plot of the sensory data from Example 5.

[0078] Examples

[0079] The examples are intended to illustrate the invention and are not intended to limit the invention to those examples perse. Methods

[0080] Analysis by GC-MS

[0081] Samples were analysed in triplicate by dynamic headspace gas chromatography with mass spectrometry detection (GC-MS), using a dynamic headspace sampler integrated with a multipurpose sampler and a thermal desorption unit (all from Gerstel GmbH).

[0082] Solid material was ground to a powder under liquid nitrogen in a mortar and kept at - 80°C prior to weighing the powder (1.0 g) into a 20 ml headspace vial, after which it was kept refrigerated prior to the analysis.

[0083] The samples were agitated in the system’s agitator at 500 rpm until equilibrium in the gas phase was reached (e.g. 10 sec on, 1 sec off; 40°C for 10 min). Next, sample purging was performed at a purge flow rate of 30 ml / min with a total purge volume of 300 ml. Stripped compounds were transferred to the Tenax TA™ dry trap tube of the system, which was kept at 30°C. The transfer-section temperature was 150°C.

[0084] Water removal from the Tenax TA™ dry trap tube was performed at a temperature of 40°C, with a drying gas volume of 600 ml at a flow rate of 60 ml / min. Analytes were desorbed from the Tenax TA™ tube by programming the temperature from 30°C (1 min) to 250°C (5 min) at 360°C / min after an equilibration time of 5 min. The desorbed analytes were transferred from the Tenax TA™ tube to the GC injector (CIS-4, kept at -150°C) in splitless mode at a flow rate of 50 ml / min and a transfer line temperature of 250°C. Transfer of the refocused analytes to the GC column was finally performed by heating the injector from -150°C (0.1 min) to 250°C (3 min) at 12°C / sec. Transfer was performed in split mode with a split ratio of 1 :10. The septum purge of the injector was 3 ml / min.

[0085] The MS detector was an Agilent Technologies 5977 MSD in El mode (70 eV). The transfer line temperature was 280°C. Ion source and quadrupole temperature were 230°C and 150°C, respectively. Mass spectra were scanned over the m / z range 33 to 250 at 3.3 spectra per second. Calibration was performed using a calibration line prepared by dissolving different levels of standard compounds (purchased from Sigma Aldrich, NL) in sunflower oil. Ethanol was quantified using a calibration line prepared in water. Compounds for which no standards were available were quantified using peak areas (counts). The amounts were expressed in ppm or counts depending on whether a standard was used.

[0086] Premix viscosity

[0087] Premix viscosity was measured in 17 mm profiled rheology cups using an Anton Paar Physica MCR501 rheometer. During the measurement, the temperature was maintained at 5°C. A 17 mm profiled bob geometry was immersed in the sample. The sample was equilibrated until constant temperature is achieved. A shear rate sweep was then conducted on the sample using the following measurement profile: shear rate range between 0.001 and 1000 s-1(logarithm spacing), with measurement point duration between 100 and 30 s, and slope of 10 points per decade. Shear rate (s-1) vs viscosity (Pa.s) was plotted, and the viscosity at 50 s-1was noted.

[0088] Oil droplet size distribution

[0089] Oil droplet size distribution was measured using a Malvern Mastersizer 3000 equipped with a wet dispersion unit to determine surface weighted mean droplet size (Da,2). The premix samples were diluted 10-fold in a solution of sodium dodecyl sulphate (SDS) and urea (6.6 M urea, 0.1% SDS, pH 7), and subjected to 1 minute of full power sonication within the dispersion unit prior to the start of particle size measurement. This treatment ensures that any weakly bound or flocculated oil droplets are separated into individual oil droplets to give a more accurate representation of the oil droplet size (such treatment cannot break up fully coalesced or aggregated oil droplets).

[0090] Example 1

[0091] Plant proteins were treated with a bioconversion agent under bioconversion conditions (40 min at 10°C). To provide comparative examples, plant proteins were treated with the bioconversion agent under fermentation conditions (16 hours at 30°C). Reference samples, which were not treated with the bioconversion agent, were also prepared. The compositions and treatments are summarised in Table 1 . The bioconversion agent used was baker’s yeast (Dr Oetker instant yeast, sold in packets of 3 individual sachets of 7 g and purchased from a Dutch supermarket). The amount of bioconversion agent used (0.18 wt%) was equivalent to 4.9 x 106CFU per g of composition. Table 1 : Plant protein compositions and treatments f Pisane C9 pea protein (Cosucra Group) * Profam 974 isolated soy protein (ADM)

[0092] The plant protein compositions were prepared as follows: the plant protein and sucrose were added to hot water (heated to 80°C) with mixing. To rule out the presence of other microorganisms, the plant protein compositions were sterilised (15 min at 110°C), and then cooled to 10°C.

[0093] The bioconversion agent (where used) was added to the cooled plant protein compositions. The samples were treated as set out in Table 1 (either by incubation at 10°C for 40 min, or at 30°C for 16 hours). Immediately after the treatment step, triplicate sets of 1 ml and 5 ml samples were taken and frozen (-80°C) for later analysis.

[0094] As expected, treatment with the bioconversion agent under fermentation conditions (16 hours at 30°C) resulted in a significant decrease in pH. In contrast, this was not seen for either the reference samples or for the plant protein solutions treated with a bioconversion agent under bioconversion conditions (40 min at 10°C).

[0095] Sensorial assessment

[0096] The liquid plant protein compositions were smelled blind by an experienced panel (of 5 to 7 panellists).

[0097] Sample 1.1 showed a clear decrease in pea off-flavour smell compared to Ref 1 . Sample 1 .A had a fermented alcoholic yeasty smell, with some CO2 production. Similarly, sample 2.1 showed a clear decrease in soy off-flavour smell compared to Ref 2. Sample 2.A had a fermented alcoholic yeasty smell, with some CO2 production.

[0098] Analysis of off-flavour markers by GC-MS

[0099] The six samples (Ref 1 , 1.1 , 1 .A, Ref 2, 2.1 , 2.A) were analysed in triplicate by dynamic headspace gas chromatography with mass spectrometry detection (GC-MS) as described above.

[0100] Table 2 summarised the analysis of off-flavour markers for Sample 1.1 compared to Ref 1 and for Sample 2.1 compared to Ref 2. The level of furfural (2-furaldehyde) was also measured, but this compound was not detected in Sample 1.1 or Sample 2.1.

[0101] Table 2: Off-flavour marker analysis

[0102] The change in off-flavour compounds is expressed as fold decrease, and calculated by dividing the amount of the off-flavour compound found in the Ref sample by the amount found in the bioconverted sample. All amounts reported are the average of triplicate measurements. The bioconversion samples showed a marked decrease in off-flavour markers compared to the Ref samples. This was the case regardless of whether the plant protein was pea protein (Sample 1.1 , Ref 1) or soy protein (Sample 2.1 , Ref 2).

[0103] Table 3 summarises the analysis of off-flavour markers for Sample 1.1 (bioconversion) compared to Sample 1.A (fermentation) and for Sample 2.1 (bioconversion) compared to Sample 2. A (fermentation). The change in off-flavour compounds is expressed as fold decrease, and calculated by dividing the amount of the off-flavour compound found in the fermented sample by the amount found in the bioconverted sample. All amounts reported are the average of triplicate measurements. A clear decrease in off-flavour markers was seen for the bioconverted samples compared to the fermented samples, irrespective of whether the plant protein was pea protein (Samples 1.1 vs 1.A) or soy protein (Samples 2.1 vs 2.A). Table 3: Off-flavour marker analysis

[0104] Example 2

[0105] To test if bioconversion is also able to decrease bitterness, further plant protein compositions were prepared using a different soy protein known to have a bitter off- flavour. Sample 3.1 was treated with a bioconversion agent under bioconversion conditions (40 min at 10°C). A reference sample (Ref 3) which was not treated with the bioconversion agent, were also prepared. The compositions and treatments are summarised in Table 4. The bioconversion agent was the same baker’s yeast as used for Example 1. The amount of bioconversion agent used (0.1 wt%) was equivalent to 2.7 x 106CFU per g of composition (or 0.7 x 108CFU per g of protein).

[0106] Table 4: Plant protein compositions and treatments

[0107] * PurePro 70P soy protein concentrate (Bunge)

[0108] Sensorial assessment

[0109] The liquid plant protein compositions were tasted by an experienced panel (of 5 to 7 panellists). Sample 3.1 showed a clear decrease in bitterness compared to Ref 3. Analysis of off-flavour markers by GC-MS

[0110] Ref 3 and Sample 3.1 were analysed by GC-MS as described above. Table 5 summarises the analysis of off-flavour markers for Sample 3.1 compared to Ref 3. The level of furfural (2-furaldehyde) was also measured, but this compound was not detected in Sample 3.1.

[0111] Table 5: off-flavour marker analysis

[0112] The change in off-flavour compounds is expressed as fold decrease, and calculated by dividing the amount of the off-flavour compound found in Ref 3 by the amount found in Sample 3.1. All amounts reported are the average of triplicate measurements. Sample 3.1 showed a marked decrease in off-flavour markers compared to Ref 3.

[0113] Example 3 Table 6: Premix compositions and treatments

[0114] Preparation of premixes

[0115] Premix compositions having the formulations shown in Table 6 were prepared as follows: Ref 4 composition:

[0116] The ingredients (excluding coconut oil) were added to hot water (heated to 80°C), and mixed, followed by addition of the coconut oil and further mixing. The mixture was pasteurised and homogenised to provide the frozen confection premix.

[0117] Compositions 4. 1, 4.2, and 4.3:

[0118] The pea protein was combined with cold water (20°C), admixed with the bioconversion agent (baker’s yeast), and then incubated at 20°C for 10 minute (Composition 3) or 30 minutes (Compositions 1 and 2) to provide a bioconverted protein solution. Inactivation of the yeast enzymes was achieved by incubating the bioconverted protein solution at 70°C for 20 minutes, after which the remaining ingredients (excluding coconut oil) were added and mixed, followed by addition of the coconut oil and further mixing. The mixtures were pasteurised and homogenised to provide the frozen confection premixes. Both the heating step (70°C for 20 minutes) and the pasteurisation step result in inactivation of the yeast enzymes

[0119] Analysis of off-flavour markers

[0120] Hexanal, which is a known marker for a beany off-note, was measured by GC-MS as described above. Samples 4.1 , 4.2 and 4.3 all had significantly reduced levels of hexanal compared to Ref 4. The reduction in hexanal was particularly pronounced for Sample 4.2.

[0121] Preparation of frozen confections

[0122] In all cases, the premixes were aged for 24 hours at 4°C, and then frozen in a scraped surface heat exchanger. The air input was controlled to give a target overrun of 100%, and freezing was controlled to give a target extrusion temperature of around -5°C.

[0123] Physical properties

[0124] Addition of the bioconversion agent did not have a significant impact on premix viscosity or fat droplet size (the smaller droplet size of premix composition 4.3 was likely due to the higher protein content of this sample). Frozen confections made from the premixes all had a good extrusion texture, and were aerated to the target overrun without issue. Sensory evaluation

[0125] A sensory assessment with a semi-trained panel (14 panellists) was performed for frozen confections made from Ref 4 and Samples 4.1 and 4.2. The composition of Samples 4.1 and 4.2 is the same, and they differ only in the duration of the bioconversion step (10 min vs 30 min). The results are shown in Figure 1 (error bars represent 95% confidence intervals). Sample 4.1 (10 min bioconversion time) was similar to Ref 4 in terms of smoothness, sweetness, bitterness, astringency and off-flavour. However, Sample 4.1 did have significantly lower pea off-notes than Ref 4, and was directionally lower in cardboard off-notes. When compared to Ref 4, Sample 4.2 (30 min bioconversion time) had significantly reduced pea and cardboard off-notes, as well as significantly lower bitterness and off-flavour. Interestingly, the texture of Sample 4.2 was judged to be significantly smoother than that of Ref 4, and additionally Sample 4.2 was reported to have a sweeter taste.

[0126] A further sensory assessment with a semi-trained panel (13 panellists) was performed for frozen confections made from Ref 4 and Sample 4.3. The sensory properties of Sample 4.3 were similar to those of Ref 4. This is surprising, since the amount of pea protein in Sample 4.3 is double the amount in Ref 4. In other words, despite containing twice as much pea protein as Ref 4, Sample 4.3 did not have the expected increase in off-notes that would typically be associated with this formulation change. In addition, the texture of Sample 4.3 was generally perceived to be smoother than that of Ref 4.

[0127] Example 4

[0128] HPAEC-PAD (high-performance anion-exchange chromatography with pulsed amperometric detection) was used to analyse the oligosaccharides present in a pea control (no bioconversion) and a bioconverted pea sample (30 min at 20°C). The results are summarised in Table 7.

[0129] Table 7: Oligosaccharide analysis using HPAEC-PAD The bioconverted pea sample shows an increase in glucose, fructose, and sucrose compared to the pea control. This could help to explain the increased sweetness reported in sensory assessments of frozen confections comprising bioconverted plant protein.

[0130] The API® ZYM kit allows semi-quantitative measurement of enzymatic activities, with each API® ZYM strip allowing the systematic and rapid study of 19 enzymatic reactions. The enzyme activity of viable yeast and non-viable (gamma irradiated) yeast was investigated using API® ZYM strips. The results are shown in Figure 2, and demonstrate that yeast enzymes are active in non-viable yeast. In particular, both viable yeast (Figure 2a) and non-viable yeast (Figure 2b) showed a-glucosidase enzyme activity (well 16, indicated with an arrow).

[0131] Premix compositions having the formulations shown in Table 8 were prepared as follows:

[0132] Ref 5 composition:

[0133] The ingredients (excluding coconut oil) were added to hot water (heated to 80°C), and mixed, followed by addition of the coconut oil and further mixing. The mixture was homogenised and pasteurised to provide the frozen confection premix.

[0134] Compositions 5. 1 and 5.2:

[0135] The pea protein was combined with cold water (20°C), admixed with the bioconversion agent (active baker’s yeast for sample 5.1 , irradiated baker’s yeast for sample 5.2), and then incubated at 20°C for 30 minute to provide a bioconverted protein solution. The bioconverted protein solution was heated at 70°C for 20 minutes, after which the remaining ingredients (excluding coconut oil) were added and mixed, followed by addition of the coconut oil and further mixing. The mixtures were homogenised and pasteurised to provide the frozen confection premixes. Both the heating step (70°C for 20 minutes) and the pasteurisation step result in inactivation of the yeast enzymes. Compositions 5. A:

[0136] The ingredients (excluding coconut oil) were added to hot water (heated to 80°C), and mixed, followed by addition of the coconut oil and further mixing. The mixture was homogenised and pasteurised, after which the bioconversion agent was added to provide the frozen confection premix. As the bioconversion agent was added after the pasteurisation step, the enzymes in the bioconversion agent were not inactivated.

[0137] Table 8: Premix compositions f Pisane C9 pea protein (Cosucra Group)

[0138] Preparation of frozen confections

[0139] In all cases, the premixes were aged for 24 hours at 4°C, and then frozen in a scraped surface heat exchanger. The air input was controlled to give a target overrun of 100%, and freezing was controlled to give a target extrusion temperature of around -5°C.

[0140] Sensory evaluation

[0141] A sensory assessment with a semi-trained panel (8 panellists) was performed for frozen confections made from Ref 5 and Samples 5.1 , 5.2, and 5. A. The results are shown in Figure 3. Samples 5.1 and 5.2 both had significantly lower pea and cardboard off-notes and bitterness compared to Ref 5, and were directionally lower in astringency. Interestingly, these samples were also judged to be significantly sweeter than Ref 5. This demonstrates that both viable and irradiated yeast are effective at reducing off-notes in unflavoured non-dairy frozen confections. Despite having significantly lower pea and cardboard off-notes compared to Ref 5, Sample 5. A had significantly increased yeast and fermentation notes. This shows that inactivation of the yeast enzymes is an important step.

Claims

Claims1. A process for preparing a frozen confection premix comprising the steps of:(a) admixing a protein composition comprising plant protein and water with a bioconversion agent comprising active enzyme(s), and incubating under non-fermentation conditions to provide a bioconverted protein composition;(b) combining additional frozen confection ingredients with the bioconverted protein composition of step (a) to provide a mixture, wherein the additional frozen confection ingredients comprise fat and sugars;(c) homogenising the mixture of step (b) to provide the frozen confection premix, wherein the frozen confection premix is an oil-in water emulsion; wherein the enzyme(s) are inactivated after step (a), after step (b), or after step (c), and wherein the incubation under non-fermentation conditions is at a temperature of 1 to 25°C for 10 to 50 minutes.

2. The process as claimed in claim 1 , wherein the plant protein is pulse protein, and preferably comprises soy protein and / or pea protein.

3. The process as claimed in claim 1 or claim 2, wherein the incubation under non- fermentation conditions is at a temperature of 1 to 22°C.

4. The process as claimed in any one of claims 1 to 3, wherein the bioconversion agent comprises active enzyme(s) selected from alcohol dehydrogenase, aldoketo reductases, aldehyde oxidase, and mixtures of two or more thereof.

5. The process as claimed in any one of claims 1 to 4, wherein the bioconversion agent is yeast.

6. The process as claimed in any one of claims 1 to 5, wherein the bioconversion agent is admixed with the protein composition such that the ratio of bioconversion agent to plant protein is 1:5 to 1 :50.

7. The process as claimed in any one of claims 1 to 6, wherein the enzyme(s) are inactivated by a pasteurisation step, preferably after step (c).

8. The process as claimed in any one of claims 1 to 7 and comprising the additional and subsequent step of:(d) ageing the premix; wherein the enzyme(s) are inactivated prior to step (d).

9. A process for preparing a frozen confection, comprising preparing a frozen confection premix by the process as claimed in any one of claims 1 to 8, and then subsequently freezing the frozen confection premix to provide the frozen confection.

10. The process as claimed in claim 9, wherein the frozen confection premix is aerated during the freezing step to provide a frozen confection having an overrun of from 30 to 150%.

11. A frozen confection premix or frozen confection comprising:• fat in an amount of 1 to 15 wt%;• sugars in an amount of 10 to 30 wt%;• bioconverted plant protein in an amount of 0.4 to 2.5 wt%; and• bioconversion agent in an amount of 0.05 to 0.5 wt%, wherein the bioconversion agent comprises inactive enzyme(s).

12. The frozen confection premix or frozen confection as claimed in claim 11 wherein the bioconversion agent is yeast.

13. The frozen confection premix or frozen confection as claimed in claim 11 or claim 12 and additionally comprising stabilizer in an amount of 0.1 to 1 wt% and emulsifier in an amount of 0.05 to 1 wt%.

4. The frozen confection premix or frozen confection as claimed in any one of claims11 to 13 comprising:• fat in an amount of 3 to 10 wt%;• sugars in an amount of 15 to 25 wt%;• bioconverted plant protein in an amount of 0.5 to 2 wt%;• bioconversion agent in an amount of 0.05 to 0.25 wt%, wherein the bioconversion agent comprises inactive enzyme(s).

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