Frozen dessert product and production method

Abstract

Herein is disclosed a method for manufacturing a frozen dessert, and a frozen dessert manufactured by the method, wherein the method comprises preparing a mix comprising hydrogen oxidizing bacteria powder, water, at least one oil, and at least one oil, homogenizing the mix, followed by pasteurizing and simultaneous whipping and freezing

Description

[0001] FROZEN DESSERT PRODUCT AND PRODUCTION METHOD

[0002] TECHNICAL FIELD

[0003] The present disclosure relates generally to frozen dessert product and methods for producing them.

[0004] BACKGROUND

[0005] Frozen desserts are edible compositions typically consumed in a solid or semi-solid frozen state. These products are made by freezing liquid or semi-liquid mixtures, which often contain a blended emulsion of ingredients such as water, dairy or non-dairy fats, sugars, stabilizers, emulsifiers, and flavoring agents. Common types include ice creams, sorbets, frozen yogurts, and gelato. The freezing process, along with air incorporation (overrun) by whisking and the stabilizing agents used, helps achieve a smooth, creamy texture and a stable structure. These desserts are generally stored and served at low temperatures to maintain their form and sensory characteristics, such as texture, mouthfeel, and flavor release.

[0006] One example of a frozen dessert is ice cream. Ice cream is an oil-in-water emulsion, and its manufacturing process involves whisking air into the ice cream to it, thereby creating the characteristic light and smooth texture and making it e.g. easier to scoop. Typical ice creams contain sugar, emulsifiers, and stabilizers, eggs for structure, and fruit purees, berries, or other ingredients for flavor. Dairy-free versions of ice cream use plant-based ingredients such as soy or oats.

[0007] In plant-based ice creams the food matrix consists of various components that are crucial for replicating the texture of traditional dairy-based ice cream. Plant-based liquids such as oat, almond, or coconut milk are used as a base, providing the necessary liquid phase and contributing to the fat content. Fats from plant-based sources, such as coconut oil or vegetable margarine, are essential for achieving the creamy and smooth texture associated with high-quality ice cream.

[0008] Hydrogen-oxidizing bacteria (HOB) are a group of microorganisms capable of utilizing hydrogen (H2) as their primary electron donor to generate energy via oxidation processes. These bacteria are generally autotrophic, using carbon dioxide (CO2) as a carbon source, and can thrive in diverse environmental conditions, including both aerobic and anaerobic settings. HOB are commonly found in soil, freshwater, marine environments, and extreme habitats, where they play a role in biogeochemical cycles by contributing to the oxidation of hydrogen gas.

[0009] A technical problem addressed by the present invention is how to create a non-dairy frozen dessert, such as non-dairy ice cream, which has a similar texture, consistency, melting behaviour and mouthfeel as dairy ice-cream. A further technical problem addressed by the present invention is how to create a typical structure of frozen desserts, such as ice cream, without additives such as emulsifiers and stabilizers. An even further technical problem addressed by the invention is how to create a typical structure of a non-dairy frozen dessert, such as non-dairy ice cream, without additives such as emulsifiers and stabilizers. Traditional ice cream relies on these additives to achieve its characteristic texture and consistency. Emulsifiers help to blend water and fat, creating a smooth and creamy texture, while stabilizers prevent the formation of ice crystals and maintain the desired consistency over time. However, there is a growing demand for natural and additive-free products. An absence of the above additives can result in a product that lacks the desired texture of ice cream, is prone to separation, and has a shorter shelf life. Therefore, there is a need to find a way to produce ice cream with the same or similar characteristics as traditional ice cream, but without relying on synthetic additives.

[0010] SUMMARY

[0011] It is an aim to solve or alleviate at least some of the problems related to prior art. An aim is to provide a frozen dessert which has soft and smoot texture, and which is resistant to melting.

[0012] The appended claims define the scope of protection. Any example and technical description of an apparatus, system, product and / or process not covered by a claim is presented as an example useful for understanding the invention.

[0013] According to the first aspect is provided a method of producing a frozen dessert, comprising: i.) preparing a mix by blending hydrogen-oxidizing bacteria (HOB) powder, water, at least one syrup, and at least one oil or at least one fat; ii.) homogenizing the mix to provide a homogenized mix; iii.) pasteurizing the homogenized mix and rapidly cooling to provide a cooled mix; iv.) whipping the cooled mix; and v.) freezing the cooled mix to form the frozen dessert.

[0014] An outline of the present method is illustrated in Fig. 1.

[0015] In an embodiment the step ii.) comprises homogenizing at a pressure of 100-1000 bar, preferably 130 bar.

[0016] In an embodiment the mix comprises 1-15 wt-%, preferably 1-10wt-%, more preferably 3- 7wt-%, most preferably about 5 wt-% of HOB powder. A HOB powder amount of 1-10wt-% is advantageous to achieve good processing properties of the mix.

[0017] In an embodiment the mix comprises 0.3-3wt-%, preferably 0.5-1.5wt-%, of at least one mixture of an emulsifier and a stabilizer selected from fatty acid monoglyceride, fatty acid diglyceride, locust bean gum, guar gum, carrageenan, xanthan gum, carboxymethyl cellulose, and sodium alginate, or any mixture thereof.

[0018] In an embodiment the mix and / or to the cooled mix is added at least one of colouring agent, flavouring agent, sweetener, pieces of fruits, nuts, chocolate, candies, cookies, caramel sauces, and fruit sauces.

[0019] In an embodiment the whipping comprises whipping for at least 10 min and at a temperature selected from the range 4-24°C, preferably at a temperature selected from the range 5- 24°C, more preferably at a temperature selected from the range 6-24°C.

[0020] In an embodiment the at least one oil or the at least one fat is selected from at least one of rapeseed oil, sunflower oil, soy oil, peanut oil, coconut oil, and lipid mixture for industrial use.

[0021] In an embodiment the HOB powder comprises biomass derived from the isolated bacterial strain deposited as VTT-E-193585, or a derivative thereof.

[0022] In an embodiment no animal-based or dairy-based ingredients are added during the method.

[0023] In an embodiment the cooled mix comprises flavouring agents, and the method comprises aging the cooled mix at 1-10°C for 4-24h, preferably at +4°C for 16 hours.

[0024] In an embodiment the frozen dessert is ice cream.

[0025] According to another aspect is provide frozen dessert manufactured by the present method and having at least one of the following characteristics:

[0026] 4-7.5mg / 100g iron, preferably 6-7mg / 100g iron; overrun of at least 5% determined by the method of Example 2.1 ; hardness of at least 5000N determined by the method of Example 4.

[0027] In an embodiment, the method does not comprise an aging step.

[0028] In an embodiment the frozen dessert has a pH in the range 6-9, preferably 6-7, more preferably 6-6.5, more preferably 6.1-6.4. The pH can be set by adding acidic and / or basic ingredients that are compatible with regulations of food industry.

[0029] According to another aspect is provided ice cream manufactured by the present method and having a HOB powder content of 3-10wt-%, and further comprising at least one colouring agent, flavouring agent, sweetener, pieces of fruits, nut, chocolate, candy, cookie, caramel sauce, or fruit sauce.

[0030] In an embodiment the ice cream is in the form of a cone, stick, cup, sandwich, or bar, and it optionally further comprises at least one coating independently selected from chocolate, caramel, fruit, or nut coatings.

[0031] BRIEF DESCRIPTION OF THE FIGURES

[0032] Some example embodiments will be described with reference to the accompanying figures, in which:

[0033] Fig. 1 shows a flow chart of the present method of producing a frozen dessert.

[0034] Fig. 2 shows flow chart of an embodiment of the present method carried out according to Example 1.

[0035] Fig. 3 shows overrun (%), calculated using the density of ice cream mixture before whipping and the density of ice cream. Each of the three ice cream recipes were made and evaluated twice, hence repetition in formula.

[0036] Fig. 4 shows hardness results of HOB powder, HOB powder + emulsifier and soy ice cream. Each ice cream was tested with three samples. The error bars represent the standard deviation of each sample.

[0037] Fig. 5 shows the melting rate of ice cream samples HOB powder, HOB powder + emulsifier, soy concentrate, a commercial dairy-based reference, and a plant-based commercial reference made from oats were evaluated. The melting of the ice cream was tested over a period of 90 minutes.

[0038] Fig. 6 shows an experimental setup to analyse melting, and HOB powder sample in the beginning and after 30 minutes of melting. DETAILED DESCRIPTION

[0039] The following strain deposition according to the Budapest Treaty on the International Recognition of Deposit of Microorganisms for the Purposes of Patent Procedure was made:

[0040] VTT-E-193585 was deposited at the VTT Culture collection, WDCM 139, VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, Fl-02044 VTT, FINLAND.

[0041] Throughout the present disclosure, the term HOB powder refers to biomass extracted from hydrogen oxidizing bacteria, for example in dehydrated form. The HOB powder provides a concentrated source of proteins with no or negligible carbohydrates, fats or any other compounds.

[0042] In an embodiment the HOB powder comprises protein, dietary fiber, and fat. HOB powder can be obtained by drying HOB biomass comprising 65-80% protein, not more than 32% dietary fiber, 5-12% fat, not more than 6.5% ash, and not more than 8% moisture, based on wet weight of the HOB biomass. As the skilled person knows, corresponding concentrations in wt-% values in HOB powder can be calculated by removing the effect of moisture.

[0043] In an embodiment the HOB powder is derived from or comprises an isolated bacterial strain of a single isolated strain of a HOB, or a derivative thereof. Said isolated bacterial strain or a derivative thereof is a gram-negative bacterium, which is genetically stable and can be grown in a broad range of process conditions. Beneficially, said strain or the derivative thereof comprises iron and vitamin B12, thereby increasing their amount in the HOB powder.

[0044] In an embodiment the HOB powder is manufactured according to the method described in EP3816293 B1 (Solar Foods Oy) Example 2 or Example 3. In another embodiment the HOB powder is manufactured according to the method described in Fl 129771 B (Solar Foods Oy), see p. 9 lines 15-27. Both, or either of, the above methods are suitable to obtain HOB powder for use in the present method.

[0045] In an embodiment the HOB powder is hydrated before preparing the mix with water.

[0046] In an embodiment the HOB powder is dry powder which is hydrated when preparing the mix with water in step i.) of the present method.

[0047] In an embodiment the HOB powder is dried HOB biomass.

[0048] In an embodiment the HOB powder has a pH in the range 7-8, preferably in the range 7.1- 7.6, more preferably about 7.3.

[0049] In an embodiment, the mix contains about 1-10 wt-% HOB powder, preferably about 1-8 wt- %, more preferably about 1-7 wt-%, more preferably about 1-6 wt-%, more preferably about 1-5 wt-%, more preferably about 1-4 wt-%, more preferably about 1-3 wt-%, and most preferably about 1-2 wt-%.

[0050] In an embodiment, the mix contains about 2-10 wt-% HOB powder, preferably about 2-8 wt- %, more preferably about 2-7 wt-%, more preferably about 2-6 wt-%, more preferably about

[0051] 2-5 wt-%, more preferably about 2-4 wt-%, and most preferably about 2-3 wt-%.

[0052] In an embodiment, the mix contains about 3-10 wt-% HOB powder, preferably about 3-8 wt- %, more preferably about 3-7 wt-%, more preferably about 3-6 wt-%, more preferably about

[0053] 3-5 wt-%, most preferably about 3-4 wt-%.

[0054] In an embodiment, the mix contains at least 1 wt-% HOB protein. In another embodiment, the mix contains at least 1.5 wt-% HOB protein. In another embodiment, the mix contains at least 2 wt-% HOB protein. In another embodiment, the mix contains at least 2.5 wt-% HOB protein. In another embodiment, the mix contains at least 3 wt-% HOB protein. In another embodiment, the mix contains at least 3.5 wt-% HOB protein. In another embodiment, the mix contains at least 4 wt-% HOB protein. In another embodiment, the mix contains at least 4.5 wt-% HOB protein. In another embodiment, the mix contains at least 5 wt-% HOB protein. In another embodiment, the mix contains at least 5.5 wt-% HOB protein. In another embodiment, the mix contains at least 6 wt-% HOB protein. In another embodiment, the mix contains at least 6.5 wt-% HOB protein. In another embodiment, the mix contains at least 7 wt-% HOB protein. In another embodiment, the mix contains at least 7.5 wt-% HOB protein. In another embodiment, the mix contains at least 8 wt-% HOB protein. In another embodiment, the mix contains at least 8.5 wt-% HOB protein. In another embodiment, the mix contains at least 9 wt-% HOB protein. In another embodiment, the mix contains at least 9.5 wt-% HOB protein. In another embodiment, the mix contains at least 10 wt-% HOB protein.

[0055] In an embodiment, the mix contains not more than 15 wt-% HOB protein. In another embodiment, the mix contains not more than 14.5 wt-% HOB protein. In another embodiment, the mix contains not more than 14 wt-% HOB protein. In another embodiment, the mix contains not more than 13.5 wt-% HOB protein. In another embodiment, the mix contains not more than 13 wt-% HOB protein. In another embodiment, the mix contains not more than 12.5 wt-% HOB protein. In another embodiment, the mix contains not more than 12 wt-% HOB protein. In another embodiment, the mix contains not more than 11.5 wt-% HOB protein. In another embodiment, the mix contains not more than 11 wt-% HOB protein. In another embodiment, the mix contains not more than 10.5 wt-% HOB protein. In another embodiment, the mix contains not more than 10 wt-% HOB protein. In an embodiment the frozen dessert contains about 0.3-3wt-%, preferably 0.3-2.8wt-%, emulsifier. This amount is advantageous for manufacturing a sorbet type of frozen dessert.

[0056] In an embodiment the amount of water refers to the total amount of water in the frozen dessert. Thus, an optional water used to hydrate HOB powder or any other ingredient is included in the total amount of water.

[0057] In an embodiment the mix contains 10-40 wt-% of at least one syrup, preferably 15-30 wt- %, more preferably 20-25 wt-% of at least one syrup.

[0058] In an embodiment the syrup is at least one of glucose syrup, starch syrup, corn syrup, high maltose syrup, maple syrup, invert sugar, honey, and maltodextrin.

[0059] In an embodiment the syrup is erythritol, maltitol, or a combination thereof.

[0060] In an embodiment the mix contains 1-10 wt-% of at least one oil or fat, preferably 2-7 wt-%, more preferably 2-5 wt-%, more preferably about 5 wt-% of at least one oil or at least one fat.

[0061] In an embodiment at least one of the mix, homogenized mix, cooled mix, and the frozen dessert, is set to pH selected from the range 6-9, preferably 6-7, more preferably 6-6.5, more preferably 6.1-6.4, or about 6.3.

[0062] In an embodiment, the method comprises homogenizing the mix at a pressure selected from the range 100-1000 bar, preferably 100-200bar, more preferably 110-180 bar, more preferably 120-150bar, most preferably 130 bar. The homogenization process at this pressure ensures that the mixture is uniformly blended, resulting in a smooth and consistent texture in the final frozen dessert product. This step has an effect for achieving the desired quality and stability of the frozen dessert and in particular ice cream, as it helps to evenly distribute the fat and other ingredients throughout the mix, preventing separation and improving the overall mouthfeel of the product.

[0063] As used herein, the term “comprising” includes the broader meanings of ’’including”, ’’containing”, and ’’comprehending", as well as the narrower expressions “consisting of” and “consisting only of”.

[0064] In an embodiment the process steps are carried out in the sequence identified in any aspect, embodiment or claim. In another embodiment any process step specified to be carried out to a product or intermediate obtained in a preceding process step is carried out directly to said product, i.e. without additional, optional or auxiliary processing steps that may chemically or physically alter the product between said two steps.

[0065] The present process is suitable for use in industrial (large) scale processes in food industry. Food-grade, or food, refers herein to compositions, mixtures, products, ingredients and / or compounds that are edible and suitable for human consumption. As used herein, suitable for human consumption does not (necessarily) imply regulatory approval.

[0066] In an embodiment preparing a mix comprises blending hydrogen-oxidizing bacteria (HOB) powder with water, at least one syrup, and at least one oil or at least one fat.

[0067] In an embodiment, the at least one oil comprises a lipid that is liquid at room temperature, optionally selected from vegetable oils, marine oils, animal oils, synthetic oils, or combinations thereof. Examples include, but are not limited to, sunflower oil, olive oil, rapeseed oil, fish oil, flaxseed oil, and synthetic oils such as medium-chain triglycerides (MCTs), hydrogenated polyisobutene.

[0068] In an embodiment, the at least one fat comprises a lipid that is solid at room temperature, optionally selected from vegetable fats, animal fats, hydrogenated fats, or structured lipids. Examples include but are not limited to cocoa butter, milk fat, lard, tallow, and mixtures thereof.

[0069] In an embodiment, the syrup is selected from at least one of corn syrup, maple syrup, agave syrup, or a combination thereof.

[0070] In an embodiment, the emulsifier is selected from at least one of fatty acid monoglyceride, fatty acid diglyceride, locust bean gum, guar gum, carrageenan, xanthan gum, carboxymethyl cellulose, sodium alginate, or a combination thereof.

[0071] In an embodiment, the colouring agent is selected from at least one of natural food coloring, artificial food coloring, or a combination thereof.

[0072] In an embodiment, the flavouring agent is selected from at least one of vanilla extract, chocolate flavor, fruit flavor, or a combination thereof.

[0073] In an embodiment, the sweetener is selected from at least one of sugar, stevia, honey, or a combination thereof.

[0074] The present method may comprise further treatment or processing. For example, the method may comprise further freezing, and / or shaping, and / or forming.

[0075] The shaping may comprise moulding. The moulding may comprise filling molds with the cooled mix and then freezing to create specific shapes and forms. This process allows creating a variety of frozen dessert products, such as ice cream bars, popsicles, and ice cream cakes.

[0076] Additionally, the method may comprise coating the frozen dessert or ice cream, wherein the coating may be, for example, chocolate, caramel, fruit puree, or a combination thereof. The coating can enhance the flavor and texture of the dessert. In an embodiment the coating is applied on a moulded or shaped frozen dessert product.

[0077] The present ice cream mixtures, that are examples of frozen dessert mixtures, are colloidal systems, where fat droplets are dispersed and surrounded by a layer of proteins and emulsifiers. Emulsifiers help maintain the dispersion and prevent the droplets from coalescing. It ensures that the fat is present in small, well-distributed droplets rather than separating from the mixture. The stability of the emulsion also influences the mouthfeel, preventing the ice cream from becoming grainy, providing uniform consistency.

[0078] Advantageously, HOB powder and an emulsifier provide surprisingly good overrun performance, as seen in the results of Fig. 3.

[0079] Advantageously, HOB powder and an emulsifier provide surprisingly good melting resistance, as seen in the results of Fig. 5.

[0080] Advantageously, the HOB powder alone, in an absence of any additional emulsifier, provided a higher hardness than soy ice cream or an ice cream containing HOB powder and emulsifier, as seen in Fig. 4. The ice cream sample containing HOB powder and emulsifier had a higher hardness than soy ice cream, but not as high as the ice cream containing only HOB powder. Depending on the intended use, it is thus possible to adjust the hardness of the frozen dessert product by using a certain amount of HOB powder alone, or supplement the HOB powder with an emulsifier to increase hardness.

[0081] The final microstructure of ice cream is thus a combination of small ice crystals, air cells, partially coalesced fat droplets, and an unfrozen phase containing sugars, proteins, and stabilizers. This multiphase structure is essential for the sensory qualities of ice cream, including its smooth texture, creaminess, as well as resistance to melting.

[0082] In ice cream production, foaming and emulsion structures are closely linked. Emulsifiers stabilize the oil and water mixture, ensuring even fat droplet dispersion. A stable emulsion is vital for maintaining a consistent foam structure during freezing. As the mixture is whipped, air bubbles are incorporated and stabilized by fat droplets, preventing coalescence. The mixing action breaks larger air bubbles into smaller ones, which are then stabilized by fat droplets and other stabilizers. During freezing, air is incorporated, creating a foam structure with dispersed air cells. These air cells contribute to the ice cream's lightness and creaminess, supported by the fat network and protein-stabilized interfaces, ensuring a smooth mouthfeel and sensory appeal.

[0083] In ice cream production, an unfrozen serum phase remains liquid upon freezing due to dissolved sugars, proteins, and stabilizers, which lower the freezing point of water. This liquid phase helps maintain smoothness, softness and e.g. ease of scooping. During the freezing and whipping step, a complex microstructure is formed with air cells, ice crystals, fat globules, and the unfrozen serum phase. Rapid freezing and optional stabilizers and emulsifiers, prevent large ice crystal formation, ensuring a smooth texture. Sugar not only serves as a sweetener, but also controls ice content and texture by lowering the freezing point.

[0084] In an embodiment pasteurization involves heating the mixture to a temperature above 72°C for a minimum duration of 15 seconds. In an embodiment pasteurization inactivates bacterial or microbial contaminants. Although the temperature needs to be high enough to reduce the number of viable micro-organisms, a temperature above 85°C should be avoided to prevent any off flavours. Pasteurization can be carried out as a batch pasteurization, which may cause more protein denaturation which can contribute to the ice cream texture as giving it more body. A continuous pasteurizing method can also be carried out in a high temperature short time heat exchanger continuously with a holding period of 15 seconds. Pasteurization can provide an enhancement to the aroma and flavour of ice cream by protecting it from flavour degrading bacteria.

[0085] In an embodiment, the rapid cooling is performed by using liquid nitrogen to achieve a temperature of approximately -30°C to -40°C.

[0086] In an embodiment, the rapid cooling is performed by using compressed air to achieve a temperature of approximately -30°C to -40°C.

[0087] In an embodiment, the rapidly cooling is performed by placing the mixture into a blast freezer with a temperature ranging from -30°C to -40°C.

[0088] In an embodiment, the rapid cooling is performed by using a combination of liquid nitrogen and compressed air to achieve a temperature of approximately -30°C to -40°C.

[0089] In an embodiment the rapid cooling is carried out by cooling in a blast chiller for 50-90min.

[0090] In an embodiment the ingredients for ice cream are selected based on the desired composition, and the recipe is calculated accordingly. The ingredients are weighed and added to the mix before, and / or after pasteurization.

[0091] In an embodiment, the method comprises adding at least one of the colouring agent, flavouring agent, or sweetener to the mix after pasteurization. This embodiment is advantageous because by adding these ingredients after pasteurization it is possible to better preserve their functional and sensory properties. Pasteurization involves heating the mixture to high temperatures to destroy potential pathogens and reduce spoilage organisms. This process can also degrade or alter properties of certain ingredients. By adding such ingredients after pasteurization, their desired characteristics are maintained, ensuring a high-quality final product.

[0092] In an embodiment the ice cream mixture is homogenized to create an emulsion by applying high-pressure forces to break down fat globules into smaller particles, and to achieve a uniform distribution. The homogenization step in step iii.) is preferably performed at or near the pasteurizing temperature. A thinner mixture is produced, resulting in a smooth product. Homogenizing pressure varies with fat content and total solids; higher fat content requires lower pressure. Homogenization increases the surface area and forms a membrane around the fat globules, thereby enhancing texture and stability of the final product. Homogenization in step iii.) has an effect of achieving a smooth texture and preventing fat clumping.

[0093] In an embodiment the method comprises aging the cooled mix at 1-10°C for 4-24h, more preferably at below 6°C for 4-24h, more preferably at below 5°C for 4-24h, more preferably at below 4°C for 4-24h. In another embodiment the method comprises aging the cooled mix at 1-6°C for 4-24h, more preferably 1-5°C for 4-24h, more preferably at 1-4°C for 4-24h.

[0094] In an embodiment the method comprises aging the cooled mix at 1-10°C for 4-20h, more preferably at below 6°C for 4-20h, more preferably at below 5°C for 4-20h, more preferably at below 4°C for 4-20h. In another embodiment the method comprises aging the cooled mix at 1-6°C for 4-20h, more preferably 1-5°C for 4-20h, more preferably at 1-4°C for 4-20h.

[0095] In an embodiment the method comprises aging the cooled mix at 1-10°C for 4-16h, more preferably at below 6°C for 4-16h, more preferably at below 5°C for 4-16h, more preferably at below 4°C for 4-16h. In another embodiment the method comprises aging the cooled mix at 1-6°C for 4-16h, more preferably 1-5°C for 4-16h, more preferably at 1-4°C for 4-16h.

[0096] In an embodiment the cooled mix is filtered before whipping.

[0097] In an embodiment whipping is carried out at a temperature selected from 4-24°C, preferably at a temperature selected from 5-24°C, more preferably at a temperature selected from 6- 24°C.

[0098] In an embodiment, whipping is carried out at a temperature selected from 4-24°C, preferably from 4-18°C, more preferably from 4-16°C, more preferably from 4-14°C, more preferably from 4-13°C, more preferably from 4-12°C, more preferably from 4-11°C, more preferably from 4-10°C, more preferably from 4-9°C, more preferably from 4-8°C, more preferably from 4-7°C, more preferably from 4-6°C, and most preferably from 4-5°C. In an embodiment, whipping is carried out at a temperature selected from 5-24°C, preferably from 5-18°C, more preferably from 5-16°C, more preferably from 5-14°C, more preferably from 5-13°C, more preferably from 5-12°C, more preferably from 5-11°C, more preferably from 5-10°C, more preferably from 5-9°C, more preferably from 5-8°C, more preferably from 5-7°C, and most preferably from 5-6°C.

[0099] In an embodiment, whipping is carried out at a temperature selected from 6-24°C, preferably from 6-18°C, more preferably from 6-16°C, more preferably from 6-14°C, more preferably from 6-13°C, more preferably from 6-12°C, more preferably from 6-11°C, more preferably from 6-10°C, more preferably from 6-9°C, more preferably from 6-8°C, and most preferably from 6-7°C.

[0100] In a preferred embodiment whipping is carried out at about 5°C.

[0101] In an embodiment whipping is carried out in a separate whipping device, from which the whipped material is transferred to a cooling device.

[0102] In an embodiment the method comprises whipping the cooled mix, followed by freezing the cooled mix. Whipping may comprise further cooling of the cooled mix. In an embodiment the temperature is not lowered during the whipping step iv.) to reach the temperature in the freezing step v.).

[0103] In an embodiment the cooled mix is whipped and frozen simultaneously. Liquid nitrogen or compressed air can be used in freezing and to achieve a temperature of approximately - 30°C. As freezing of water occurs in this embodiment, air bubbles generated by the whipping freeze within the mixture, contributing to its characteristically light texture. The rapid cooling process has an effect of preventing ice crystal growth and maintaining a smooth consistency. Freezing and whipping air into the ice cream mixture is also useful for long term storage.

[0104] In an embodiment, after the ice cream is whipped and cooled down, it is packaged and set to freeze. In an embodiment it is placed into a blast freezer with a temperature ranging from -30°C to -40°C. This phase is called hardening of ice cream, and its purpose is to reduce ice crystal growth and thereby ensure smooth and pleasant texture even after long-term storage.

[0105] In an embodiment the method comprises temperature monitoring throughout the whole process to ensure product quality and consumer safety. Faster and colder freezing helps to achieve a smoother ice cream. Ice cream production in industrial scale is comparable to production in a test kitchen. However, some modifications may be made in the process. In an embodiment homogenization may be carried out separately before pasteurization.

[0106] In the context of the present method emulsifiers are surfactants that reduce surface tension between immiscible substances, allowing small droplets of one substance to be distributed in another. For example, in an ice cream emulsion, fat droplets are dispersed in the aqueous phase. Emulsifiers stabilize these droplets by reducing surface tension, preventing clumping, and ensuring a smooth texture, and in this manner serve as stabilizers. Preferably, emulsifiers are added to increase viscosity and to maintain a uniform mixture.

[0107] In an embodiment an emulsifier is at least one of gum, gum arabic, lecithin, monoglyceride, diglycerides, agar-agar, guar gum, lecithin, polysorbate, sorbitan ester of fatty acid, and polysorbate 80. Additional emulsifiers and / or stabilizers include locust bean gum, guar gum, carboxymethyl cellulose, sodium alginate, xanthan gum, and carrageenan.

[0108] Proteins and proteinaceous ingredients may also have an important role in stabilizing emulsions, such as oil-in-water emulsions, which are commonly found in frozen desserts and ice creams. The amphiphilic nature of proteins allows them to lower an interfacial tension between oil and water, forming stable emulsions in food formulations. Plant-based proteins typically exhibit lower emulsifying capacity than animal proteins. This lower capacity can result in less stable emulsions, negatively impacting the texture and mouthfeel of products like ice cream. Modifications through physical, chemical, or enzymatic methods have been used to enhance the structure and functionality of plant proteins, improving their emulsifying properties in frozen desserts. Additionally, further emulsifiers can be added to achieve desired product characteristics.

[0109] HOB powder has surprisingly been found to show emulsifying abilities that can be used in frozen desserts to form stable foam. The hydrophilic and hydrophobic properties of the proteins in HOB powder contribute to stabilizing emulsions, offering an improved alternative to plant proteins. HOB powder can meet the needs of the frozen dessert industry, maintaining the product’s desired quality and stability. Thus, HOB powder can be used to fully or at least partially replace emulsifiers in frozen desserts, such as in ice cream.

[0110] Preferably, in the present frozen dessert the HOB powder is present as an emulsifier and / or stabilizer.

[0111] In an embodiment the step i.) comprises mixing water and any powder material such as HOB powder, adding oil with mixing, adding syrup with mixing, and preheating. In a preferred embodiment adding oil with mixing involves mixing at about 800rpm until temperature is raised to about 50°C, and then mixing is continued at about 3000rpm and then at about 700-8500rpm before syrup is added. In a preferred embodiment syrup is added while mixing at about 3000rpm.

[0112] In an embodiment at the end of step i.) the mix is pre-heated to about 70°C by mixing at 500-8500rpm.

[0113] In an embodiment the homogenization step directly follows the pre-heating.

[0114] In an embodiment the pasteurization step directly follows the homogenization.

[0115] In an embodiment the rapid cooling step in step iii.) comprises cooling to below 6°C.

[0116] In an embodiment the cooled mix is aged at about 4°C for about 16h.

[0117] In an embodiment the whipping is continued for about 10min.

[0118] In an embodiment, the frozen dessert contains iron about 4-7.5 mg / 100g, preferably 4.5-

[0119] 7.5 mg / 100g, more preferably 5-7.5 mg / 100g, more preferably 5.5-7.5 mg / 100g, more preferably 6-7.5 mg / 100g. In another embodiment the frozen dessert contains iron about 4- 7.3 mg / 100g, preferably 4.5-7.3 mg / 100g, more preferably 5-7.3 mg / 100g, more preferably 5.5-7.3 mg / 100g, more preferably 6-7.3 mg / 100g. In an embodiment, the frozen dessert contains iron about 4-7 mg / 100g, preferably 4.5-7 mg / 100g, more preferably 5-7 mg / 100g, more preferably 5.5-7 mg / 100g, more preferably 6-7 mg / 100g. In an embodiment the frozen dessert contains iron about 4-6.5 mg / 100g, preferably 4.5-6.5 mg / 100g, more preferably 5-

[0120] 6.5 mg / 100g, more preferably 5.5-6.5 mg / 100g, more preferably 6-6.5 mg / 100g. These iron values may distinguish the product from other commercially available frozen desserts. They may also provide a source of iron where it is beneficial, e.g. in frozen desserts suitable for vegan diets.

[0121] In an embodiment, the frozen dessert has an overrun of at least 5% as determined by the method of Example 2.1 , preferably at least 10%, more preferably at least 15%, more preferably at least 20%, more preferably at least 25%, more preferably at least 30%, more preferably at least 35%, more preferably at least 40%, more preferably at least 45%. These overrun values provide a frozen dessert which has a good texture and pleasant mouthfeel in sensory evaluation.

[0122] In an embodiment, the frozen dessert has an overrun of 5-50% as determined by the method of Example 2.1 , preferably 5-45%, more preferably 5-40%, more preferably 5-35%, more preferably 5-30%, more preferably 5-25%, more preferably 5-20%, more preferably 5- 15%, more preferably 5-10%. These overrun values provide a frozen dessert which has a good texture and pleasant mouthfeel in sensory evaluation. In an embodiment, the frozen dessert has an overrun of 10-50% as determined by the method of Example 2.1 , preferably 10-45%, more preferably 10-40%, more preferably 10- 35%, more preferably 10-30%, more preferably 10-25%, more preferably 10-20%, more preferably 10-15%. These overrun values provide a frozen dessert which has a good texture and pleasant mouthfeel in sensory evaluation.

[0123] In an embodiment, the frozen dessert has an overrun of 15-50% as determined by the method of Example 2.1 , preferably 15-45%, more preferably 15-40%, more preferably 15- 35%, more preferably 15-30%, more preferably 15-25%, more preferably 15-20%. These overrun values provide a frozen dessert which has a good texture and pleasant mouthfeel in sensory evaluation.

[0124] In an embodiment, the frozen dessert has an overrun of 20-50% as determined by the method of Example 2.1 , preferably 20-45%, more preferably 20-40%, more preferably 20- 35%, more preferably 20-30%, more preferably 20-25%. These overrun values provide a frozen dessert which has a good texture and pleasant mouthfeel in sensory evaluation.

[0125] In an embodiment, the frozen dessert has a hardness of 4000-6000 N as determined by the method of Example 4, preferably 4200-6000 N, more preferably 4400-6000 N, more preferably 4600-6000 N, more preferably 4800-6000 N, and most preferably 5000-6000 N. These hardness values provide a frozen dessert which has a good texture, pleasant mouthfeel, and advantageous melting properties.

[0126] In a further advantage of the present invention, the specific combination of the manufacturing steps, and in particular the use of HOB powder, provides at least one of improved texture, increased stability, and increased resistance to melting, preferably even without the use of additional emulsifiers or stabilizers.

[0127] Some further embodiments are described below:

[0128] Embodiment 1 . A method of producing a frozen dessert, comprising: i.) preparing a mix by blending hydrogen-oxidizing bacteria (HOB) powder, water, at least one syrup, and at least one oil or at least one fat; ii.) homogenizing the mix to provide a homogenized mix; iii.) pasteurizing the homogenized mix and rapidly cooling to provide a cooled mix; iv.) whipping the cooled mix; and v.) freezing the cooled mix to form the frozen dessert. Embodiment 2. The method of embodiment 1 , wherein the step ii.) comprises homogenizing at a pressure of 100-1000 bar, preferably 130 bar.

[0129] Embodiment 3. The method of embodiment 1 or 2, wherein the mix comprises 1-15 wt-%, preferably 2-10wt-%, more preferably 3-7wt-%, most preferably about 5 wt-%, of HOB powder.

[0130] Embodiment 4. The method of any one of embodiments 1-3, wherein the mix comprises 0.3-3wt-%, preferably 0.5-1.5wt-%, of at least one mixture of an emulsifier and a stabilizer selected from fatty acid monoglyceride, fatty acid diglyceride, locust bean gum, guar gum, carrageenan, xanthan gum, carboxymethyl cellulose, and sodium alginate, or any mixture thereof.

[0131] Embodiment 5. The method of any one of embodiments 1-4, wherein to the mix and / or to the cooled mix is added at least one of colouring agent, flavouring agent, sweetener, pieces of fruits, nuts, chocolate, candies, cookies, caramel sauces, and fruit sauces.

[0132] Embodiment 6. The method of any one of embodiment 1-5, wherein the whipping comprises whipping for at least 10 min and at a temperature selected from the range 4-24°C, preferably at a temperature selected from the range 5-24°C, more preferably at a temperature selected from the range 6-24°C.

[0133] Embodiment 7. The method of any one of embodiments 1-6, wherein the at least one oil or the at least one fat is selected from at least one of rapeseed oil, sunflower oil, soy oil, peanut oil, coconut oil, and lipid mixture for industrial use.

[0134] Embodiment 8. The method of any one of embodiments 1-7, wherein the HOB powder comprises biomass derived from the isolated bacterial strain deposited as VTT-E-193585, or a derivative thereof.

[0135] Embodiment 9. The method of any one of embodiments 1-8, wherein no animal-based or dairy-based ingredients are added.

[0136] Embodiment 10. The method of any one of embodiments 1-9, wherein the cooled mix comprises flavouring agents, and the method comprises aging the cooled mix at 1-10°C for 4-24h, preferably at +4°C for 16 hours.

[0137] Embodiment 11. The method of any one of embodiments 1-10, wherein the frozen dessert is ice cream.

[0138] Embodiment 12. A frozen dessert manufactured by the method of any of the embodiments 1-11 and having at least one of the following characteristics:

[0139] 4-7.5mg / 100g iron, preferably 6-7mg / 100g iron; overrun of at least 5% as determined by the method of Example 2.1 ; hardness of at least 5000N as determined by the method of Example 4.

[0140] Embodiment 13. The frozen dessert of embodiment 12 having a pH in the range 6-9, preferably 6-7, more preferably 6-6.5, more preferably 6.1-6.4.

[0141] Embodiment 14. Ice cream manufactured by the method of any one of embodiments 1-11 and having a HOB powder content of 3-10wt-%, and further comprising at least one colouring agent, flavouring agent, sweetener, pieces of fruits, nut, chocolate, candy, cookie, caramel sauce, or fruit sauce.

[0142] Embodiment 15. The ice cream of embodiment 14, wherein the ice cream is in the form of a cone, stick, cup, sandwich, or bar, and wherein it optionally further comprises at least one coating independently selected from chocolate, caramel, fruit, or nut coating.

[0143] Examples

[0144] The following examples are provided to better illustrate the claimed invention and are not to be interpreted as limiting the scope of the invention. To the extent that specific materials, machines, and operating parameters are mentioned, it is merely for purposes of illustration and is not intended to limit the invention, which is defined in the appended claims. The skilled person understands that e.g. when practicing the claimed invention by using a different machine or apparatus, some operating parameters may be different to achieve the same, similar, or corresponding effect as achieved in the following Examples.

[0145] Materials and ingredients

[0146] Ingredients used when preparing the present frozen dessert, of which ice cream serves in the following as an example, included water, syrups (glucose syrup, starch syrup), coconut oil, and rapeseed oil. Maltodextrin, soy concentrate, and HOB powder were also incorporated, with one recipe featuring either HOB powder, soy concentrate, or maltodextrin.

[0147] An objective of certain examples was to assess replacing emulsifiers and stabilizers by HOB powder. Therefore, a commercial blend containing both an emulsifier and a stabilizer was added to certain ice cream formulations. The commercial emulsifying and stabilizing ingredient contains mono- and diglycerides of fatty acids (E471), locust bean gum (E410), guar gum (E412) and non-technofunctional antioxidants. This commercial blend will subsequently be referred to as "emulsifier". The purpose of varying the inclusion of the emulsifying and stabilizing ingredient was to evaluate the differences between formulations with and without a traditional emulsifying and stabilizing component. Table 1. Machines used in the examples and a purpose each machine was used for.

[0148] Example 1. Production of ice cream emulsions

[0149] The preparation process for the frozen dessert samples, ice cream samples in the example, involved several controlled steps. First, cold tap water was weighed and added to the thermocutter bowl. Powders were then added, and the mixture was mixed in the thermocutter at 3000 rpm for two minutes. Following this, the speed was reduced to 120 rpm and mixing continued with a mixing paddle for ten minutes to ensure the powders were evenly dispersed.

[0150] Next, oils were added to the mixture, and the speed was adjusted to 800 rpm. The temperature was set to 50°C, and mixing proceeded until the mixture reached 50°C or until the oils were fully incorporated. After removing the mixing paddle, the mixing speed was increased again to 3000 rpm for two minutes, followed by an increase to 7000-8500 rpm for five minutes to ensure thorough emulsification.

[0151] Syrup was then added, and the mixture was blended at 3000 rpm for five minutes, followed by an increase to 7000-8500 rpm for an additional four minutes. A pre-heat treatment was conducted to ensure the temperature reached at least 70°C, at which point the product was ready for homogenization. The temperature of the mixture was recorded before homogenization.

[0152] Homogenization in the final experimental protocol was performed at a pressure of 130 bar with a homogenizer (GEA PandaPLUS Lab Homogenizer). Different homogenizing pressures were tested in the preliminary phase. The mixture was homogenized into glass jars from the outlet spout, after which the product underwent pasteurization. Pasteurization was carried out in an oven set to 100°C with 100% humidity for 20 minutes, starting once the product reached 85°C. After pasteurization, the product was transferred to a blast chiller for rapid cooling, where it remained for 60 minutes. The glass jars with the ice cream mixture in them were shaken during cooling to prevent freezing. Once cooled, the product was stored in cold storage at +4°C for 16 hours to allow aging.

[0153] After aging, the mixture was removed from cold storage and whipped for 10 minutes. To prevent temperature fluctuations, the batches were briefly returned to cold storage before being processed in the ice cream machine. Once processed, the ice cream was transferred into containers and placed in a freezer for final storage. pH of the prepared ice cream samples was in the range 6.19-6.30 with an average of 6.25.

[0154] Figure 2 shows in a flow chart the phases in making ice cream according to Example 1.

[0155] Example 2. Experimental protocol

[0156] Following a preliminary phase of experimentation with various production methods and recipe formulations, the process of creating research samples was initiated. The preliminary phase involved systematically testing and refining different ingredient ratios, mixing techniques, ageing periods and homogenizing conditions to identify the optimal parameters for desired textural and sensory qualities. The selection of these parameters was based on their potential to enhance the stability, mouthfeel, and flavor profile of the final product.

[0157] Based on preliminary tests, homogenization and whipping time were standardized for the research samples. Homogenization in the final experimental protocol was performed at a pressure of 130 bar with a homogenizer (GEA PandaPLUS Lab Homogenizer). All samples are whipped with a food processor (Hobart) for 10 minutes after the aging period, before processing in an ice cream machine.

[0158] The final experimental protocol was conducted on samples with formulations that included HOB powder, HOB powder combined with an emulsifier, and soy concentrate, which will subsequently be referred to as "soy”. The three ice cream recipe processes were repeated three times over the course of three weeks. Some tests such as the foaming test were repeated during the experimental study period. The samples are described in Table 2.

[0159] Table 2. Samples used in final experiments. All three recipes are repeated three times. RS4-RS6 were processed using the Wilfa ice cream machine due to product loss. RS1-RS3 are made the same as RS7-RS9. Recipes are repeated to have enough product for analysis.

[0160] All research samples were prepared following a consistent set of production steps, to systematically examine the impact of different ingredient compositions. These variations were designed to isolate and assess key factors influencing the melting properties, overrun, hardness, and sensory qualities of ice cream. By comparing these samples, the study aimed to identify formulation and preparation conditions that would provide insights into the underlying mechanisms affecting the quality of the product, thereby addressing the core research question.

[0161] Foaming tests in the final experiments were conducted in the same manner as in the preliminary experiments. After a 16-hour aging period, 40 grams of each ice cream mixture was weighed before and after whipping. Each 40-gram sample was measured in a 100 mL graduated cylinder. The mixtures were whisked using a food processor for 10 minutes per sample.

[0162] In the preliminary tests, whipping ability was only assessed by comparing the volume of the ice cream mixture before and after whipping. To obtain a more accurate measure of the amount of air incorporated into the ice cream, an additional method was designed based on density of the ice cream mix and the density of the ice cream. A sample was placed into a cup with a capacity of 75 mL, with any excess levelled off at the rim. The samples were weighed, and their density values were calculated.

[0163] Example 2.1 - Overrun

[0164] Overrun was calculated by comparing the density of the mixture (cooled mix) to the density of ice cream. Overrun by density was calculated with the following formula: 100 % Example 3. Melting test

[0165] The melting test setup includes a scale, a tripod, a round metal trivet, and a bowl. Each ice cream sample was cut into a cube with the same length, height, and depth. Each sample was quickly measured on a scale before the melting test to calculate the mass loss in percentages to create a melting rate curve. The weight on the scale of the melted ice cream was tracked every five minutes and every 10 minutes after a total of 40 minutes had passed. The melting test was performed for a total of 90 minutes for each sample.

[0166] Example 4. Hardness test

[0167] For the hardness measurements the texture analyzer (TA.XTplusC Texture Analyzer) was used. The analysis was executed by using a reversible blade, a slotted blade insert, and a blade holder. The blade cuts through the ice cream sample and draws a curve on the connected lap top screen. The test results were analyzed with Microsoft Excel. Each ice cream sample was cut into approximately the same shape and size with the same measurements in length, height and depth. Notes were taken from each sample for later reading of the test results. Some of the ice cream samples adhered to the blade during test running, which should be considered when interpreting the results.

[0168] Example 5. Sensory analysis

[0169] A sensory evaluation was conducted on samples HOB powder, HOB powder + emulsifier, soy, and maltodextrin (T14). The evaluation was performed in a test kitchen by three panellists. A scoop of each ice cream sample was placed in individual sample cups. Each panellist was given a tray with each of the four samples, a spoon, a cup of water and a cup for tasted ice cream. The samples were numbered to minimize any preconceived notions from the panellists and ensure objective results. Each of the three panellists completed an online form, where they were asked to provide a description of each sample. The panellists were asked to describe the mouthfeel of the ice cream, whether the sample appeared uniformly mixed, and how it melted in the mouth. Additionally, they were asked to assess the creaminess and richness of each sample, as well as compare the samples to one another.

[0170] Results

[0171] Preliminary tests

[0172] The ice creams were prepared as similarly as possible to ensure comparability between the samples. Differences in the ice cream recipes included specific ingredients, such as the protein-containing component, and their respective quantities. None of the ice creams produced during the study contained flavouring components to allow for the most precise evaluation of the inherent properties of the ice creams. Table 3 includes all relevant samples in the preliminary tests. Different homogenizing pressures and whipping times were tested on the preliminary samples.

[0173] Table 3. Samples used in preliminary tests.

[0174] An overrun value indicates the percentage increase in volume between the ice cream mixture and the final ice cream product. Incorporating air into the mixture can improve even distribution of ingredients, enhance the smoothness of texture, and create a more uniform colour. Air content may also be increased for economic reasons, as a high overrun (i.e. , a higher proportion of air in the mixture) allows for more ice cream to be produced from the same amount of ingredients. A low overrun signifies a lower air content, while a high overrun indicates that the product contains a significant amount of air relative to the ice cream base. Gelato typically has a low overrun, while soft-serve ice cream tends to have a higher overrun value.

[0175] In a preliminary foaming test for recipes with HOB powder + emulsifier sample T2 was whipped for 25 minutes and had a lower (110.5 %) overrun than T3 (131.6 % overrun) with a whipping time of 10 minutes.

[0176] The preliminary sensory evaluation test assessed the characteristics of the samples. The panel was asked to evaluate whether the samples were different from each other, what was the overall acceptability, how was the texture and how the sample melted in the mouth. Finally, they were asked to select the best samples from each test, if possible. In the sensory evaluation test, samples T7 and T10 were first evaluated to decide at which pressure to homogenize the research samples. T7 was homogenized at 130 bar and T10 at 1000 bar pressure. According to the panel, there were hardly any differences between the samples. The texture of both was found to be pleasant, soft and very smooth in the mouth. T10 was perceived as melting slightly better in the mouth. A slight difference in taste was noted in the T7 sample. The differences were very small and not observed by all the panel members, so the sensory evaluation had little influence on the homogenization pressure standardization.

[0177] Homogenization pressure had no significant effect on foaming ability of HOB powder ice cream. Sample T7 with a homogenization pressure of 130 bar and a whipping time of 10 min had the optimal overrun value. Sample T7 had an overrun value of 38,5 % and sample T10 had an overrun value of 38.2 %. Hence the overrun value difference being insignificant, other factors were considered more in deciding on the processing parameters of the research samples.

[0178] All samples T7-T10 were also subjected to a preliminary melting test. The melting test was carried out by cutting ice cream into same sized cubes and placed on a large single colored surface to observe the melting residue. The preliminary melting test was done over a total of 60 minutes. There were only minor differences between samples T7 and T10. Sample T7 showed a more pronounced difference between the sample cube shape and melting residue, while sample 10 melted more shallowly. T7 therefore melted slightly more stably, which contributed to the decision to choose a homogenization pressure of 130 bar for the research samples. All samples showed a low degree of coagulation, i.e. the fat and water phases were separated from the sample during melting. Sample T9 showed the highest degree of coagulation.

[0179] Whipping time was another parameter to be optimized in the preliminary tests. Samples T7, T8 and T9 were included in a preliminary sensory evaluation test to find possible difference in characteristics of the samples to standardize the optimal whipping time. There were little differences in the samples which indicated that the whipping time had little influence on the sensory characteristics of ice cream. Therefore, other qualities had more value in the standardization of process parameters.

[0180] The overrun value has potential to directly affect the commercial possibilities of the frozen dessert products. When comparing samples T7-T9, sample T7 with 10 minutes of whipping time had an overrun value of 38.5 % and sample T8 with 5 minutes of whipping time had an overrun value of 28.2 % which is significantly lower than T7. T9 had the lowest overrun value of 24.4 % which was the least optimal result regarding the research question. Based on the overrun value, the optimal whipping time would be for sample T7, which had a whipping time of 10 minutes. Therefore, whipping time of 10 minutes has been standardized for the production process of the research samples. The correlation between whipping time and volume was shown to increase in the preliminary tests.

[0181] To study the effect of HOB powder on aging, further ice cream samples were prepared. Sample T12 was processed into ice cream immediately after pasteurization and chilling, and sample T13 was allowed to age at +4°C for about 16 hours. These samples were made with the same recipe, homogenization pressure and whipping time as T7, 10 minutes. T12 did form a foam structure, like sample T7. The sample T12 overrun value was 45.95%, which is higher than the T7 value of 38.46% because the T12 reference had a smaller volume than the T7 sample possibly due to aging time of 0 h. The sample T13 overrun value was 36.84%, which is relatively lower than T12.

[0182] In the pre-tests of this study, the recipe Maltodextrin 5% + emulsifier 0.75% without HOB powder was tested. First, maltodextrin and water were combined, and coconut oil was heated separately, to which a small amount of emulsifier and rapeseed oil was added. The mixtures were then combined, and the mixture was completed according to the recipe. The mixture was processed with an immersion blender to distribute the emulsifier better. The mixture looked slightly better than previous samples containing maltodextrin, but the phases in the mixture still separated after a short time.

[0183] Maltodextrin with emulsifier was theoretically perceived as a very potential reference sample recipe for comparison with samples containing HOB powder, hence a change in the preparation method was used to obtain a valid maltodextrin ice cream mass. A slightly higher concentration of emulsifier was tested than in the previous pre-tests, as the emulsifier dosing instructions state that emulsifier should be weighed by 0.75% per 10% fat content. The fat content in all the pre-tests was 12%. Sample T14 was prepared with 5% maltodextrin and 0.8% emulsifier. The mixture was smooth in the mixer, but after the final mixing stage, large fat droplets were visible in the mixture. The mixture was homogenised and, the following day, after aging, was produced, as with the other ice creams. The separation of the oil phase made homogenization more difficult, and the mixture extracted from the machine partly runnier and partly denser. The mixture was pasteurized and cooled according to the normal recipe. After aging overnight, the mixture was whipped for 10 minutes and processed in an ice cream machine for 17 minutes to obtain a sorbet-like texture. After the aging period, whipping endorsed combining the water and oil phases. The maltodextrin ice cream was packaged like the other ice creams and left to the storage freezer. Maltodextrin 5 % could have been a potential candidate for the final experiments due to its possibilities in showing the main differences between ice cream formulations with and without HOB powder. Because maltodextrin ice cream formulations in several preliminary tests failed to form an adequate emulsion without changing the preparing method it was excluded from the final experiments protocol. The sample T14 was, however, included in the sensory evaluation test to compare with the other samples for possible development purposes after this project. Soy concentrate ice cream was another possible sample to be tested in the final experiments. The soy samples in the preliminary tests were successful, which led to including it in the final experimental protocol.

[0184] Foaming

[0185] Figure 3 shows overrun rates of ice cream samples RS1-R6 calculated using the density of ice cream mixture before whipping and the density of ice cream.

[0186] The mixture containing an emulsifier was difficult for the homogenizer to process, leading to greater variability in homogenization pressure during the preparation of HOB powder + emulsifier samples and the subsequent soy sample. The homogenizing pressure reached a peak of 255 bar during homogenization of the soy mixture. The soy mixture was also difficult to homogenize after HOB powder + emulsifier mixture, which may have influenced the RS3 results. After the initial batches (RS1-RS3), the HOB powder + emulsifier mixture was homogenized last to avoid similar issues.

[0187] Each of the three ice cream recipes were made and evaluated twice. In the initial foaming experiment (samples RS1-RS3), the ice cream machine encountered difficulties processing the HOB powder + emulsifier ice cream mix. The ice cream mixture exhibited a texture that was excessively fluffy and stiff, leading to an inconsistent freezing process. This may have resulted from an imbalance in the formulation, such as an overabundance of air incorporated during the mixing stage. Given that HOB powder possesses emulsifying properties, and the recipe also included the recommended amount of emulsifier, it is possible that the combined emulsifying components were excessive. This suggests that the recipe could be optimized by reducing the quantity of emulsifier used. These factors likely explain the anomalous results for samples RS1-RS3.

[0188] The highest overrun calculated by density is observed in RS5, the sample containing HOB powder with an emulsifier, reaching over 120% overrun. This result is consistent with the previous volume-based overrun results, reaffirming that the combination of HOB and emulsifier significantly enhances the incorporation of air during the ice cream production process. The high overrun density implies that the ice cream has a substantial air retention. RS2, another sample containing HOB powder with an emulsifier, shows a moderately elevated overrun density at around 30%. While this is higher than samples without an emulsifier, it is significantly lower than RS5. This difference might indicate that the issues with the ice cream machine in making RS2 prevented it from achieving the same level of aeration as RS5. However, the result still highlights the emulsifier’s role in improving air retention compared to samples lacking emulsifiers.

[0189] Samples RS1 and RS4, which consist of HOB without emulsifiers, show lower overrun densities, around 10% and 20%. These results suggest that HOB alone is less effective at stabilizing air incorporation, leading to denser ice cream with less air and a heavier texture.

[0190] The soy-based samples, RS3 and RS6, demonstrate low overrun densities of about 9%. These results suggest that soy has a limited ability to stabilize air in ice cream.

[0191] The overrun data supports the conclusion that the addition of emulsifiers enhances air incorporation and retention in HOB powder based ice cream formulations.

[0192] Hardness

[0193] The hardness of ice cream refers to its ability to resist deformation when subjected to an external force. Several factors influence ice cream’s hardness, including the amount of air incorporated during freezing, the size of the ice crystals, the volume of the ice phase, melting rate, both room and ice cream temperature, and the degree of fat destabilization.

[0194] Figure 4 shows the texture analyzer hardness results of HOB powder, HOB powder + emulsifier, and soy ice cream. The figure shows both average and the standard deviation. Each ice cream was tested with three samples to minimize likeliness of random errors.

[0195] The results from the texture analyzer of three different ice cream formulations HOB powder, HOB powder + emulsifier, and soy reveal important insights into their performance. The average hardness values show that the HOB powder formulation has the highest result (6292 g), followed by HOB powder + emulsifier (5614 g), and soy (3611 g).

[0196] Looking at the standard deviations, which indicate the spread of the data, the HOB powder sample demonstrates the lowest variability (183 g). In contrast, the soy formulation exhibits the highest standard deviation (730 g). The HOB powder + emulsifier sample falls between these two, with a moderate standard deviation of 305 g.

[0197] HOB powder sample shows the highest performance and consistency in the hardness test with texture analyzer, suggesting it is the hardest formulation among the three. This may indicate that HOB powder based ice cream needs a little time to soften before consuming depending on consumer preferences. Adding an emulsifier slightly reduces the average value and introduces more variability, but the formulation remains moderately consistent. On the other hand, the soy formulation not only has the lowest average but also shows significant variability, making it the least desirable option based on these results. This suggests that HOB powder, particularly without emulsifiers, may be the hardest ice cream of the group.

[0198] Melting

[0199] Table 4 shows the recorded temperature of each sample at the beginning of melting test. Samples HOB powder, HOB powder + emulsifier, soy, commercial dairy, and commercial oat were tested on the same day.

[0200] Table 4. Temperature of samples in the beginning of melting test. The room temperature during the melting tests was 20.6 °C. Samples are HOB powder, HOB powder + emulsifier, Soy, Commercial dairy, and Commercial oat were tested.

[0201] Figure 5 shows the different melting curves for ice cream samples HOB powder, HOB powder and emulsifier, soy concentrate, commercial dairy, and a commercial oat ice cream. Both commercial samples have a vanilla flavour. Commercial dairy contains egg and locust bean gum, which may affect its performance. Commercial oat contains locust bean gum, guar gum, and mono and diglycerides, which might influence the melting properties. Melting time in minutes is shown on the horizontal axis and the mass loss percentage on the vertical axis. The image shows that the HOB powder sample has melted in a manner like the commercial dairy-based ice cream sample. In contrast, the commercial oat-based sample has melted in a significantly different way compared to any other sample. Additionally, the commercial oat sample has melted the least in terms of percentage. Both the HOB powder + emulsifier sample and the commercial oat sample have melted slowly, releasing entire pieces of ice cream at a time, whereas, for instance, the HOB powder and commercial dairy samples have melted steadily in droplets.

[0202] Figure 6 shows HOB sample in the beginning and after 30 minutes of melting test. The sample seems to melt in a stable way. The shape of the sample has slightly changed through melting. In Figure 6, HOB powder + emulsifier, depicted by the squares, shows a lower degree of mass loss throughout the melting period. It does not fully melt down onto the scale during the 90-minute period of the melting test. This suggests that the emulsifier has a strong effect on stabilizing the ice cream mixture, significantly reducing the overall mass loss compared to HOB alone.

[0203] For the sample HOB + emulsifier, after 30 minutes of melting test the block of ice cream seems to slowly fall through the metal trivet, but the shape of the ice cream seems to stay similar compared to the beginning of melting.

[0204] The soy formulation, represented by the solid line with triangles in Fig. 5, shows a faster melting rate, with a steep increase in mass loss beginning around 20 minutes. This suggests that the soy-based formulation lacks the structural stability of the other samples, leading to rapid melting. After 30 minutes of melting test, the soy ice cream block looks visually melted and has a glossy texture.

[0205] Commercial dairy, indicated by the solid line with letter x in Fig. 5, has a melting pattern like HOB powder, but it melts faster, reaching 90% mass loss at around 50 minutes. This could be due to differences in fat content and emulsifier use in commercial formulations. After 30 minutes of melting test the ice cream block looks visually melted and has a glossy texture.

[0206] The commercial oat formulation, indicated by solid line with stars in Fig. 5 exhibits a slow melting process initially but accelerates after 50 minutes, showing a total mass loss of around 55% by the end of the experiment. Its melting behavior is somewhat unique, as it appears more stable at first, but loses its structure more quickly after the midpoint. After 30 minutes of melting test, the block of ice cream seems to slowly fall through the metal trivet, but the shape of the ice cream seems to stay the same compared to the beginning of melting.

[0207] In the melting test HOB powder + emulsifier showed the highest stability with the lowest mass loss, while the soy formulation has the fastest melting rate. HOB powder and commercial dairy both exhibit high melting rates but perform slightly worse than the HOB powder + emulsifier mix. HOB powder and commercial dairy have a similar melting curve, even when the dairy ice cream contains a stabilizer. This could be an indicator that HOB powder ice cream could have a positive effect on the melting properties of ice cream. Commercial oat demonstrates intermediate performance, initially slow to melt but losing mass more rapidly as time progresses.

[0208] Sensory evaluation

[0209] Table 5 includes all samples tested in the sensory evaluation exam. The sample containing maltodextrin, from the previous tests, was included in the sensory evaluation test due to general interest that arose during the preliminary tests. Table 5. Recipe of the sensory evaluation samples.

[0210] The texture of all the samples is smooth and evenly mixed. However, sample maltodextrin stands out negatively due to its watery, rubbery, and grainy texture, in contrast to the creamier and fuller-bodied textures of samples HOB powder + emulsifier, HOB powder, and soy. Among these, sample HOB powder + emulsifier is noted as the creamiest and most full-bodied, while samples HOB powder and soy also show slight signs of wateriness but still maintain a creamy texture.

[0211] Regarding mouthfeel and melting characteristics, sample maltodextrin is described as icy at first and then thin, lacking the creaminess of typical of ice cream. In comparison, samples HOB powder + emulsifier, HOB powder, and soy were perceived as creamier and richer. Sample HOB powder + emulsifier stands out as the creamiest, while sample HOB powder is perceived as slightly denser. Sample soy is noted for its pleasant and lighter mouthfeel, with a more typical melting pattern for ice cream. The melting speed also varies, with sample maltodextrin melting quickly, resembling a sorbet, whereas the other samples melt more slowly.

[0212] In terms of flavour, samples HOB powder + emulsifier and HOB powder are considered the best, with a soft and rich taste, although both show a slight coconut oil aftertaste. Sample soy has a stronger plant protein flavour compared to the others. Sample maltodextrin has the lowest rating in terms of taste, with a bland aftertaste and an unpleasant lingering of coconut fat in the mouth.

[0213] The aging time may have had an influence on the results as all samples were set to age at the same time but whipped and processed into ice cream one after another. A longer period of aging time may benefit texture and flavour development. Samples HOB powder + emulsifier, HOB powder, and soy are generally creamy and more pleasant in terms of mouthfeel, while sample maltodextrin stands out negatively due to its watery texture, graininess, and sorbet-like melting properties.

[0214] Conclusions

[0215] Three different formulations were tested in the Examples: one using HOB powder, another combining HOB powder with an emulsifier, and a soy concentrate, referred to as “soy”. These recipes were repeated three times over three weeks to ensure reliability, and certain tests, like foaming, were conducted twice. The homogenization pressure and whipping times for all ice cream samples were standardized after the preliminary tests to ensure consistency. The final experimental protocol involved homogenizing the ice cream mix at a pressure of 130 bar. After an aging period of 16 hours, all samples were whipped for 10 minutes using a Hobart food processor before being processed in an ice cream machine.

[0216] Overrun was assessed through both volume and density measurements to provide a broad perspective of air incorporation into the ice cream. The results revealed that samples containing both HOB powder and an emulsifier (RS2 and RS5) had the highest overrun values, exceeding 140%. By contrast, the HOB powder only samples (RS1 and RS4) exhibited lower overrun values, around 40%, indicating that HOB can incorporate some air, but the effect is enhanced with emulsifier. The soy-based samples (RS3 and RS6) showed moderate overrun values, with RS3 having the lowest at around 20%.

[0217] The results confirm that HOB powder possesses emulsifying properties. Since the formulation of HOB powder + emulsifier included a recommended amount of emulsifier, it is possible that the combined emulsifying components were excessive, making the mixture difficult to handle for the ice cream machine. Thereby the recipe could be optimized by reducing the amount of added emulsifier. The HOB powder thus appears to be suitable for partially or fully replacing other emulsifiers.

[0218] The texture analysis of the three formulations revealed that the HOB powder sample had the highest average hardness (6292 g) with the lowest variability, indicating it produced the hardest and most consistent ice cream. This aligns with the foaming test results. The addition of an emulsifier slightly reduced hardness (5614 g) but still produced moderately consistent results, while the soy-based formulation had the lowest hardness (3611 g) and the highest variability, suggesting it is the least consistent and hard option. The addition of an emulsifier had an increasing effect on the high air content of HOB powder ice cream, which has likely affected the hardness test results.

[0219] In the melting test, the HOB powder formulation showed a high rate of melting, with mass loss remaining low for the longest period. By contrast, HOB powder + emulsifier exhibited greater stability. The soy formulation melted the fastest. HOB powder and commercial dairy ice cream have a similar melting curve, even when the dairy ice cream contains a stabilizer. This could suggest that HOB powder ice cream could perform similarly as dairy ice cream.

[0220] A small sensory evaluation was conducted with three panelists who tasted the HOB powder, HOB powder + emulsifier, soy, and maltodextrin (T14) samples. Each panelist was given a tray of numbered samples to minimize bias, and feedback was collected through an online form. The sensory data supported the findings that emulsifiers enhance the sensory properties by improving texture and air incorporation, but HOB powder only sample was overall well accepted by the panel alongside of the HOB powder + emulsifier sample. It was surprisingly found that the combination of HOB powder and an emulsifier improved overrun, hardness, and melting rate in ice cream formulations. The HOB powder formulations performed equally or even better than formulations with soy concentrate.

[0221] HOB powder may at least partially replace emulsifiers and stabilizers in ice cream. Ice cream containing HOB powder has similar melting behavior as dairy ice cream and it has similar ability to incorporate air as soy ice cream

[0222] The scope of protection sought for various embodiments of the invention is set out by the independent claims. Any example or embodiment not falling within the scope of the independent claims is presented herein as an additional example or additional embodiment useful for understanding the claimed invention.

Claims

CLAIMS1 . A method of producing a frozen dessert, comprising: i.) preparing a mix by blending hydrogen-oxidizing bacteria (HOB) powder, water, at least one syrup, and at least one oil or at least one fat; ii.) homogenizing the mix to provide a homogenized mix; iii.) pasteurizing the homogenized mix and rapidly cooling to provide a cooled mix; iv.) whipping the cooled mix; and v.) freezing the cooled mix to form the frozen dessert.

2. The method of claim 1 , wherein the step ii.) comprises homogenizing at a pressure of 100-1000 bar, preferably 130 bar.

3. The method of claim 1 or 2, wherein the mix comprises 1-15 wt-%, preferably 2- 10wt-%, more preferably 3-7wt-%, most preferably about 5 wt-%, of HOB powder.

4. The method of any one of claims 1-3, wherein the mix comprises 0.3-3wt-%, preferably 0.5-1.5wt-%, of at least one mixture of an emulsifier and a stabilizer selected from fatty acid monoglyceride, fatty acid diglyceride, locust bean gum, guar gum, carrageenan, xanthan gum, carboxymethyl cellulose, and sodium alginate, or any mixture thereof.

5. The method of any one of claims 1-4, wherein to the mix and / or to the cooled mix is added at least one of colouring agent, flavouring agent, sweetener, pieces of fruits, nuts, chocolate, candies, cookies, caramel sauces, and fruit sauces.

6. The method of any one of claims 1-5, wherein the whipping comprises whipping for at least 10 min and at a temperature selected from the range 4-24°C, preferably at a temperature selected from the range 5-24°C, more preferably at a temperature selected from the range 6-24°C.

7. The method of any one of claims 1 -6, wherein the at least one oil or the at least one fat is selected from at least one of rapeseed oil, sunflower oil, soy oil, peanut oil, coconut oil, and lipid mixture for industrial use.

8. The method of any one of claims 1-7, wherein the HOB powder comprises biomass derived from the isolated bacterial strain deposited as VTT-E-193585, or a derivative thereof.

9. The method of any one of claims 1-8, wherein no animal-based or dairy-based ingredients are added.

10. The method of any one of claims 1-9, wherein the cooled mix comprises flavouring agents, and the method comprises aging the cooled mix at 1-10°C for 4-24h, preferably at +4°C for 16 hours.

11. The method of any one of claims 1-10, wherein the frozen dessert is ice cream.

12. A frozen dessert manufactured by the method of any of the claims 1-11 and having at least one of the following characteristics:4-7.5mg / 100g iron, preferably 6-7mg / 100g iron; overrun of at least 5% as determined by the method of Example 2.1 ; hardness of at least 5000N as determined by the method of Example 4.

13. The frozen dessert of claim 12 having a pH in the range 6-9, preferably 6-7, more preferably 6-6.5, more preferably 6.1-6.4.

14. Ice cream manufactured by the method of any one of claims 1-11 and having a HOB powder content of 3-10wt-%, and further comprising at least one colouring agent, flavouring agent, sweetener, pieces of fruits, nut, chocolate, candy, cookie, caramel sauce, or fruit sauce.

15. The ice cream of claim 14, wherein the ice cream is in the form of a cone, stick, cup, sandwich, or bar, and wherein it optionally further comprises at least one coating independently selected from chocolate, caramel, fruit, or nut coatings.

Images