Method of making enteral nutritional compositions

Abstract

The present invention relates to a method of preparing a shelf-stable liquid enteral nutritional composition comprising the steps of providing an oil-in-water emulsion, sterilizing the emulsion by direct steam injection (DSI) to obtain a sterilized emulsion having an F0 value of at least 3, and homogenizing the sterilized emulsion at high pressure.

Description

Technical Field

[0001] The present invention relates to a method for preparing a shelf-stable liquid enteral nutritional composition, said method comprising a sterilization step using direct heating followed by a high pressure homogenization step. Background Art

[0002] The nutritional composition needs to be heat treated (such as pasteurization or sterilization) to ensure product safety and quality. w ), food matrix, viscosity, homogeneity, storage temperature and desired shelf life, determine the type of thermal treatment to ensure product safety.

[0003] "Commercial sterility" of a food product is defined as the absence of microorganisms capable of growing in the product under normal (non-refrigerated) conditions to which the food may be subjected during manufacture, distribution, and storage.

[0004] The greatest safety concern when food products are stored at ambient temperature is the growth of Clostridium botulinum. This microorganism is a spore-forming bacterium that is highly heat-resistant, grows at a pH of 4.5 or above, and is strictly anaerobic. Therefore, if these microorganisms survive in thermally processed foods and conditions are favorable for growth, these microorganisms may grow in the absence of oxygen.

[0005] The F0 value is a measure of the combined effect of time and temperature on the sterilization of C. botulinum spores. The value is calculated as follows:

[0006]

[0007] Where t = sterilization time in minutes and where T is the sterilization temperature in °C. The z value is specific to each microorganism and represents the temperature increase required to achieve a tenfold reduction in time. For Clostridium botulinum, the z value is 10.

[0008] Sterilization (F0 ≥ 3) is applied to obtain commercial sterility of products with a longer shelf life. Heat treatments for products with a shorter shelf life are usually milder and in most cases are combined with other factors that inhibit microbial growth, such as acidity, water activity (Aw) and refrigeration. Milder heat treatments are usually pasteurization steps (e.g., 72°C for 15s).

[0009] Heat treatment of the nutritional composition can be accomplished by direct or indirect heating. An example of direct heating is direct steam injection (DSI). The nutritional composition is directly contacted with hot steam under strictly controlled conditions. The sterilization temperature is quickly reached, and after holding, the temperature is reduced by flash cooling in a vacuum container. Rapid heating and cooling introduces minimal heat load to the nutritional composition.

[0010] When indirect heating is used, a spacer is placed between the nutritional composition and the heating or cooling medium. The principle is that the hot medium flows on one side of the spacer, and the nutritional composition is on the other side. Without any direct contact between the hot medium and the nutritional composition, the spacer is heated and the heat is transferred to the nutritional composition flow. The same principle applies to cooling. Examples of indirect heating equipment are plate heat exchangers, tubular heat exchangers or scraped-surface heat exchangers.

[0011] Within the category of liquid enteral nutritional dairy compositions, there are different types such as coffee creamer, medical nutritional compositions, high calorie nutritional compositions, high whey protein nutritional compositions, infant nutrition, etc. Each composition has its own unique challenges in terms of shelf stability and also in terms of convenience of consumption and appeal to consumers or patients.

[0012] For example, the preparation of liquid enteral nutritional compositions with high whey protein levels at neutral pH presents challenges. The high temperatures required for sterilization lead to denaturation and subsequent aggregation of whey proteins, resulting in increased turbidity or increased viscosity, and / or may lead to gelling of the composition. Therefore, liquid, shelf-stable nutritional compositions with high levels of native whey protein contain little or relatively low amounts of whey protein, i.e., typically less than 8 wt.% of the product.

[0013] The present invention relates to such a shelf-stable liquid enteral nutritional composition having a lower level of whey protein. A typical method for preparing these compositions comprises the following steps:

[0014] a. mixing an aqueous phase having a water-soluble component including a protein with an oil phase to obtain an oil-in-water emulsion;

[0015] b. pasteurizing the oil-in-water emulsion to obtain a pasteurized oil-in-water emulsion;

[0016] c. Applying a first high pressure homogenization to obtain an oil-in-water emulsion with a reduced oil droplet size. The smaller the oil droplet size, the more stable the oil-in-water emulsion;

[0017] d. cooling the homogenized oil-in-water emulsion and refrigerating;

[0018] e. sterilizing the homogenized oil-in-water emulsion by ultra-high temperature (UHT) treatment using an indirect heating method;

[0019] f. Apply a second high pressure homogenization to the sterilized water-in-oil emulsion to further reduce the oil droplet size to improve the stability of the final product.

[0020] In the art, the application of both a pasteurization step and a sterilization step, as well as a high pressure homogenization step before and after the sterilization step, is considered essential for the stability of these types of products.

[0021] For example, WO 2007050521 describes the preparation of instant infant formula. In example 1.1-1.3, the preparation of infant formula is described, by preparing the carbohydrate-mineral slurry comprising water and skim milk powder, protein-oil mixture is prepared separately, and protein-oil mixture is mixed with carbohydrate-mineral slurry, pH is adjusted to 6.68-6.75, heated to 71 ℃-82 ℃, emulsified under 900-1100psig (62-76 bar) by single-stage homogenizer, heated to 146 ℃ and continued for about 5 seconds, flash cooling, and the blend through cooling is homogenized under 3900-4100 / 400-600psig (269-283 / 28-41 bar). After standardization and pH adjustment, the finished product is then placed in a suitable container and final sterilization is carried out. Summary of the invention

[0022] The inventors of the present invention have surprisingly found that a shelf-stable liquid enteral nutritional composition with lower levels of whey protein can be prepared in a more efficient process. Compared to standard processing methods in the art, when the sterilization step is performed by direct steam injection (DSI), as described herein before, no pasteurization step and high pressure homogenization are required before the sterilization step.

[0023] It was unexpectedly found that, in addition to sterilization, heat treatment with DSI also has a beneficial effect on the particle size distribution of the nutritional composition obtained after a high pressure homogenization step following the sterilization step. A more uniform particle size distribution and a more uniform distribution of ingredients in the nutritional composition were obtained.

[0024] In addition, even though DSI sterilization requires more energy than indirect heat sterilization, the method according to the present invention still has a lower carbon footprint than conventional methods. The carbon footprint is reduced by eliminating the pasteurization step and the autoclave step before the sterilization step.

[0025] Besides being a more efficient process, the process according to the invention also produces a product with a more attractive colour and a better taste, for example less fishy smell when fish oil is present in the product.

[0026] More particularly, the present invention provides a method for preparing a shelf-stable liquid enteral nutritional composition comprising, by weight of the composition:

[0027] - 0.5-13 wt.% protein, wherein the protein comprises up to 7 wt.% whey protein by weight of the composition;

[0028] -2-10 wt.% oil;

[0029] -6-30 wt.% digestible carbohydrates;

[0030] -50-90 wt.% water;

[0031] The method comprises the following steps:

[0032] a. Providing an oil-in-water emulsion, wherein the particles in the emulsion have a volume-weighted mode diameter of at least 3 μm;

[0033] b. sterilizing the emulsion by direct steam injection (DSI) to obtain a sterilized emulsion having an F0 value of at least 3;

[0034] c. subjecting the sterilized emulsion to high pressure homogenization at a total pressure of at least 200 bar to obtain a nutritional composition, wherein the particles in the nutritional composition have a volume weighted mode diameter of less than 2 μm. DETAILED DESCRIPTION

[0035] Thus, a first aspect of the present invention relates to a method for preparing a shelf-stable liquid enteral nutritional composition comprising, by weight of the composition:

[0036] - 0.5-13 wt.% protein, wherein the protein comprises up to 7 wt.% whey protein, based on the weight of the composition;

[0037] -2-10 wt.% oil;

[0038] -6-30 wt.% digestible carbohydrates;

[0039] -50-90 wt.% water;

[0040] The method comprises the following steps:

[0041] a. Providing an oil-in-water emulsion, wherein the particles in the emulsion have a volume-weighted mode diameter of at least 3 μm;

[0042] b. sterilizing the emulsion by direct steam injection (DSI) to obtain a sterilized emulsion having an F0 value of at least 3;

[0043] c. subjecting the sterilized emulsion to high pressure homogenization at a total pressure of at least 200 bar to obtain the nutritional composition, wherein the particles in the nutritional composition have a volume weighted mode diameter of less than 2 μm.

[0044] As used herein, the term "shelf-stable nutritional composition" refers to a nutritional composition that does not require refrigeration and has a shelf life of at least 3 months, preferably 6 months.

[0045] As used herein, the term "shelf life" is the period from its date of manufacture during which a product remains suitable for consumption.

[0046] The term "ambient temperature" as used herein refers to a temperature of 15-30°C, preferably 20-25°C, most preferably 20°C.

[0047] As used herein, the term "enteral nutritional composition" refers to a nutritional composition that is consumed orally or administered directly into the gastrointestinal tract via a tube.

[0048] The term "oil" as used herein refers to the sum of one or more selected from the group consisting of free fatty acids, monoglycerides, diglycerides and triglycerides and polar lipids (such as phospholipids, cholesterol, glycolipids, sphingomyelin). The terms "lipid", "oil" and "fat" will be used interchangeably herein and will have the same meaning.

[0049] The volume of the particles and their size distribution may be suitably determined using a particle size analyzer such as a Mastersizer 2000 (Malvern Instruments, Malvern, UK), for example by the method described by Michalski et al., 2001, Lait 81:787-796.

[0050] The volume weighted mode diameter relates to the diameter of the most present particles based on the volume percentage of total lipid, or the peak in a graph with diameter on the X-axis and volume (%) of total lipid on the Y-axis.

[0051] As used herein, the term "high pressure homogenization under total pressure" refers to increasing the pressure or pressures used in a single homogenization device.

[0052] The term "viscosity" as used herein refers to the viscosity measured using an Anton Paar Physica MCR301 rheometer with a CP50-1 / PC cone (50 mm diameter, 1° difference between the middle and the outer portion) at 20°C, 100 s-1 The viscosity is measured below.

[0053] Step a)

[0054] The method comprises the step of providing an oil-in-water emulsion, wherein the particles in the emulsion have a volume weighted mode diameter of at least 3 μm. Preferably, the volume weighted mode diameter of the particles in the oil-in-water emulsion is between 3.5-20 μm, more preferably between 4-15 μm, and most preferably between 4.5-10 μm.

[0055] Preferably, the oil-in-water emulsion is prepared by:

[0056] - providing an aqueous phase comprising water and water-soluble ingredients;

[0057] - providing an oil phase comprising oil and lipid components;

[0058] - emulsifying the aqueous phase and the oily phase to obtain an oil-in-water emulsion having particles having a volume-weighted mode diameter of at least 3 μm.

[0059] Preferably, the water phase and the oil phase are emulsified under low shear conditions to obtain an oil-in-water emulsion. The emulsification of the water phase and the oil phase under low shear conditions is preferably carried out by a homogenizer with a total pressure of up to 150 bar, by an in-line mixer and / or by in-line dosing the oil phase into the water phase. More preferably, the emulsification of the water phase and the oil phase is carried out by an in-line mixer and / or by in-line dosing the oil phase into the water phase. Most preferably, the emulsification of the water phase and the oil phase is carried out by an in-line mixer.

[0060] During the preparation of the oil-in-water emulsion in step a), preferably a heat treatment is applied up to 80°C, more preferably a heat treatment is applied to 40-70°C and most preferably a heat treatment is applied to 50-60°C.

[0061] The provided oil-in-water emulsion of step a) preferably has a pH above 6.0, more preferably a pH above 6.2, even more preferably a pH between 6.4-8.0 and most preferably a pH between 6.5-7.5.

[0062] The provided oil-in-water emulsion of step a) preferably has a dry matter content of at least 5 wt.% based on the weight of the oil-in-water emulsion, more preferably a dry matter content between 10-50 wt.% based on the weight of the oil-in-water emulsion.

[0063] Step b)

[0064] The method comprises the step of sterilizing the emulsion by direct steam injection (DSI) to obtain a sterilized emulsion having an F0 value of at least 3.

[0065] Preferably, sterilization is accomplished by ultra high temperature (UHT) treatment using DSI. More preferably, such UHT treatment using DSI is performed at a temperature of at least 135°C for 1-20 seconds, provided that F0 is at least 3. Even more preferably, such UHT treatment using DSI is performed at a temperature between 140°C and 160°C for 3-15 seconds, and most preferably at 145°C and 155°C for 5-10 seconds, provided that F0 is at least 3.

[0066] Preferably, the sterilized emulsion has an F0 value between 3-130, more preferably an F0 value between 4-95, and most preferably an F0 value between 5-60.

[0067] In a preferred embodiment, step b) of the method is the only sterilization step in the method.

[0068] Step c)

[0069] The method comprises the step of subjecting the sterilized emulsion to high pressure homogenization at a total pressure of at least 200 bar to obtain a nutritional composition, wherein the particles in the nutritional composition have a volume weighted mode diameter of less than 2 μm.

[0070] The particles in the nutritional composition preferably have a volume weighted mode diameter of less than 1.6 μm, more preferably less than 1.2 μm and more preferably between 0.1-0.8 μm.

[0071] In a preferred embodiment, the volume weighted mode diameter of the particles in the nutritional composition is reduced by at least 1 μm compared to the volume weighted mode diameter of the particles in the oil-in-water emulsion due to the high pressure homogenization step in step c). More preferably, the volume weighted mode diameter of the particles in the nutritional composition is reduced by at least 1.5 μm compared to the volume weighted mode diameter of the particles in the oil-in-water emulsion due to the high pressure homogenization step in step c). Most preferably, the volume weighted mode diameter of the particles in the nutritional composition is reduced by at least 2 μm compared to the volume weighted mode diameter of the particles in the oil-in-water emulsion due to the high pressure homogenization step in step c).

[0072] Preferably, the high pressure homogenization is performed at a total pressure of 250-1500 bar, more preferably at a total pressure of 300-1200 bar, and most preferably at a total pressure of 350-800 bar.

[0073] Preferably, the high pressure homogenization is carried out at a temperature of up to 90°C, more preferably at a temperature between 40°C and 80°C, and most preferably at a temperature between 50°C and 60°C.

[0074] Preferably, after step c) of the method, the obtained nutritional composition is aseptically packaged in a package having a volume of 50 to 2000 ml to obtain a packaged nutritional composition. Preferably, the package has a volume of 75 to 1000 ml, and more preferably, the package has a volume of 100 to 500 ml. Preferably, the package is a laminated cardboard package (e.g. Tetra ) or bottle.

[0075] Preferably, the packaged nutritional composition has a shelf life of at least 6 months at ambient temperature. More preferably, the packaged nutritional composition has a shelf life of at least 9 months at ambient temperature, and most preferably, the packaged nutritional composition has a shelf life of at least 12 months at ambient temperature.

[0076] Nutritional composition

[0077] The shelf-stable liquid enteral nutritional composition obtainable by the process comprises, by weight of the composition:

[0078] - 0.5-13 wt.% protein, wherein the protein comprises up to 7 wt.% whey protein by weight of the composition;

[0079] -2-10 wt.% oil;

[0080] -6-30 wt.% digestible carbohydrates;

[0081] -50-90 wt.% water.

[0082] Preferably, the nutritional composition has a pH above 6.0, more preferably a pH above 6.2, even more preferably a pH between 6.4-8.0 and most preferably a pH between 6.5-7.5.

[0083] Preferably, the nutritional composition has a caloric density of 55-250 kcal / 100 ml, more preferably a caloric density of 57-215 kcal / 100 ml, and most preferably a caloric density of 60-180 kcal / 100 ml.

[0084] Preferably, the nutritional composition has a pressure of 0.1-200 MPa . s viscosity, more preferably 0.5-160 MPa.s viscosity, and most preferably 1-120 MPa . s viscosity.

[0085] The nutritional composition preferably comprises 0.75-12 wt.% protein by weight of the composition, more preferably 1-10.5 wt.% protein and most preferably 1.25-9 wt.% protein by weight of the composition.

[0086] Preferably, less than 1 wt.% of the protein in the nutritional composition is hydrolyzed, more preferably less than 0.5 wt.% of the protein in the nutritional composition is hydrolyzed.

[0087] Preferred protein sources are dairy protein, vegetable protein and combinations thereof.

[0088] In preferred embodiments wherein the nutritional composition comprises milk protein, the milk protein is selected from casein, caseinates, whey protein and combinations thereof. More preferably, the milk protein is selected from casein, caseinates and combinations thereof. Most preferably, the milk protein is casein.

[0089] The nutritional composition preferably comprises up to 6 wt.% whey protein by weight of the composition, more preferably 0.1-4.5 wt.% whey protein by weight of the composition, and most preferably 0.2-3 wt.% whey protein by weight of the composition.

[0090] Preferably, the nutritional composition does not comprise whey protein micelles or chemically modified milk proteins, such as enzymatically cross-linked milk proteins.

[0091] In preferred embodiments wherein the nutritional composition comprises plant protein, the plant protein is selected from the group consisting of soy protein, pea protein, potato protein, oat protein, almond protein, rice protein, and combinations thereof.

[0092] The nutritional composition preferably comprises 2.2-9.8 wt.% oil by weight of the composition, more preferably 2.5-9.5 wt.% oil by weight of the composition.

[0093] Preferably, the nutritional composition comprises at least 40 wt.% vegetable oil by weight of oil, more preferably at least 60 wt.% vegetable oil by weight of oil, and most preferably 80-100 wt.% vegetable oil by weight of oil.

[0094] Preferably, the vegetable oil source in the nutritional composition is: linseed oil (or flaxseed oil), rapeseed oil (such as colza oil, canola oil and rapeseed oil), sunflower oil, high oleic sunflower oil, safflower oil, high oleic safflower oil, olive oil, coconut oil, palm oil, palm kernel oil and combinations thereof.

[0095] Preferred non-vegetable oil sources in the nutritional composition are milk fat, fish oil, microbial oil, algal oil, and combinations thereof.

[0096] The nutritional composition preferably comprises 10-50 wt.% LCPUFAs by weight of the oil. More preferably 12.5-40 wt.% LCPUFAs by weight of the oil, and most preferably 15-35 wt.% LCPUFAs.

[0097] Preferred LCPUFAs are DHA, EPA, ARA, LA, ALA and combinations thereof. DHA refers to docosahexaenoic acid and / or acyl chains (22:6, n3); EPA refers to eicosapentaenoic acid and / or acyl chains (20:5, n3); ARA refers to arachidonic acid and / or acyl chains (20:4, n6). LA refers to linoleic acid and / or acyl chains (18:2, n6); ALA refers to α-linolenic acid and / or acyl chains (18:3, n3).

[0098] The nutritional composition preferably comprises 6.5-28 wt.% digestible carbohydrates by weight of the composition, more preferably 7-26 wt.% digestible carbohydrates by weight of the composition.

[0099] Preferred digestible carbohydrates in the nutritional composition are lactose, glucose, sucrose, fructose, galactose, maltose, maltodextrin and combinations thereof.

[0100] Other preferred ingredients are one or more of the following: vitamins, minerals, non-digestible oligosaccharides, phospholipids, antioxidants, emulsifiers, nucleotides, choline, phospholipids and taurine.

[0101] The nutritional composition preferably comprises 10-50 wt.% water by weight of the composition, more preferably 11-48 wt.% water and most preferably 12-46 wt.% water by weight of the composition.

[0102] The nutritional composition preferably comprises 0.5-500 mg / 100 ml of divalent metal cations selected from Ca and / or Mg, more preferably 1-400 mg / 100 ml of divalent metal cations selected from Ca and / or Mg.

[0103] The nutritional composition preferably comprises 1-200 mg / 100 ml of vitamin C, more preferably 2-150 mg / 100 ml of vitamin C and most preferably 4-125 mg / 100 ml of vitamin C.

[0104] The nutritional composition preferably comprises 0-300 μg / 100 ml of vitamin A, more preferably 25-225 μg / 100 ml of vitamin A and most preferably 50-150 μg / 100 ml of vitamin A.

[0105] The nutritional composition preferably comprises 0.1-60 mg / 100 ml of vitamin E, more preferably 0.5-40 mg / 100 ml of vitamin E and most preferably 1-20 mg / 100 ml of vitamin E.

[0106] The nutritional composition preferably does not comprise a thickener, more preferably the nutritional composition does not comprise starch, carrageenan, and combinations thereof.

[0107] Preferably, the nutritional composition is an infant formula and / or a medical nutritional composition.

[0108] In a particularly preferred embodiment of the present invention, the nutritional composition is an infant formula.Preferably, the infant formula is selected from an infant formula, a follow-on formula or a toddler formula.

[0109] More preferably, the nutritional composition is an infant formula, wherein the nutritional composition comprises, by weight of the composition:

[0110] - 0.5-3 wt.% protein, wherein the protein comprises up to 2.5 wt.% whey protein by weight of the composition;

[0111] -2-5 wt.% oil;

[0112] -6-10 wt.% digestible carbohydrates;

[0113] -82-90wt.% water

[0114] The particles in the infant formula have a volume weighted mode diameter of less than 2 μm.

[0115] Most preferably, the nutritional composition is an infant formula, wherein the nutritional composition comprises, by weight of the composition:

[0116] - 1-2 wt.% protein, wherein the protein comprises up to 1.6 wt.% whey protein by weight of the composition;

[0117] - 2.5-4 wt.% oil;

[0118] -7-9 wt.% digestible carbohydrates;

[0119] -84-88 wt.% water

[0120] The particles in the infant formula had a volume weighted mode diameter between 0.1-0.8 μm.

[0121] The infant formula preferably comprises 0.1-10 wt.% non-digestible oligosaccharides by weight of the nutritional composition. More preferably 0.2-7.5 wt.% non-digestible oligosaccharides by weight of the nutritional composition, and most preferably 0.4-5 wt.% non-digestible oligosaccharides by weight of the nutritional composition.

[0122] Preferred non-digestible oligosaccharides are human milk oligosaccharides, fructooligosaccharides, galacto-oligosaccharides or combinations thereof.

[0123] Infant formula used herein refers to an artificially prepared nutritional composition intended for an infant of 0 to about 4 to 6 months old, and is intended as a substitute for human milk. Typically, infant formula is suitable for use as a sole source of nutrition. Such infant formula is also referred to as a section of formula. Larger infant formulas for infants from 4 to 6 months old to 12 months old after birth are intended to be supplementary feedings for infants who start weaning and eat other foods. Infant formula and larger infant formula are subject to strict regulations, such as EU regulations No. 609 / 2013 and No. 2016 / 127. Growing-up milk used herein refers to an artificially prepared nutritional composition intended for infants and children of at least 12 months, which is intended to be supplementary feedings for infants or children.

[0124] In a particularly preferred alternative embodiment of the invention, the nutritional composition is a medical nutritional composition. Examples of medical nutritional compositions are nutritional compositions for patients with disease-related malnutrition, patients with inherited metabolic disorders, patients with stroke, patients with dysphagia or patients with early Alzheimer's disease.

[0125] More preferably, the nutritional composition is a medical nutritional composition and comprises, by weight of the composition:

[0126] - 3-13 wt.% protein, wherein the protein comprises up to 7 wt.% whey protein by weight of the composition;

[0127] -2-12 wt.% oil;

[0128] -8-30 wt.% digestible carbohydrates;

[0129] -55-82 wt.% water

[0130] The particles in the medical nutritional composition have a volume weighted mode diameter of less than 1 μm.

[0131] Most preferably, the nutritional composition is a medical nutritional composition and comprises, by weight of the composition:

[0132] - 3.5-10 wt.% protein, wherein the protein comprises up to 7 wt.% whey protein by weight of the composition;

[0133] - 2.5-10 wt.% oil;

[0134] -10-27 wt.% digestible carbohydrates;

[0135] -55-82 wt.% water

[0136] The particles in the medical nutritional composition have a volume weighted mode diameter between 0.1-0.8 μm.

[0137] In this document and its claims, the verb "to comprise" and its conjugations are used in their non-restrictive sense, meaning to include the part following the word, but not to exclude parts not specifically mentioned. In addition, referring to an element by the indefinite article "a" or "an" does not exclude the possibility that more than one element is present, unless the context clearly requires that there be one and only one element. Thus, the indefinite article "a" or "an" usually means "at least one". BRIEF DESCRIPTION OF THE DRAWINGS

[0138] Figure 1 . Particle size distribution of different medical nutritional compositions (1, A, B) after sterilization and high pressure homogenization. Different sterilization techniques were compared.

[0139] Figure 2 Particle size distribution of different oil-in-water emulsions (2, 3, C) emulsified by an inline mixer at various rotation speeds before sterilization and high-pressure homogenization.

[0140] Figure 3 Particle size distribution of different oil-in-water emulsions (2, 3, C) emulsified by an inline mixer at various rotation speeds after sterilization and high-pressure homogenization.

[0141] Examples

[0142] Example 1

[0143] Three liquid enteral medical nutritional compositions were prepared (as described in Example 3) which differed from each other in the type of heat treatment applied to sterilize the products.

[0144] Production method

[0145] 1) First, dissolve the water soluble ingredients except the minerals in water using low shear mixing techniques. Dissolve the minerals separately in water and add to the main batch.

[0146] 2) After adding the water soluble ingredients, the batch was standardized by adjusting the pH to 6.8 (using potassium hydroxide) and optionally adding additional water to obtain the desired dry matter content.

[0147] 3) Heat the fat blend to 60°C and mix with the emulsifier. Add the fat blend to the rest of the batch, ensuring the oil is evenly distributed in the batch by applying low shear mixing techniques.

[0148] 4) The batch was preheated to 90°C using a tubular heat exchanger. The batch was then commercially sterilized using different sterilization treatments, see Table 1 below. Next, the product was cooled in two steps, first to 90°C and then to 65°C.

[0149] 5) Next, the batch was homogenized at an elevated pressure of 600 bar in total.

[0150] 6) Take samples from each batch to determine the particle size distribution (PSD), where the particles include the oil droplets. The PSD is determined using a Mastersizer.

[0151] Table 1

[0152] Batch Sterilization 1 Direct Steam Injection (DSI), 153°C for 3 seconds A Tubular heat exchanger, 130°C for 120 seconds B Tubular heat exchanger, 147°C for 8 seconds

[0153] result

[0154] Figure 1 The PSD of three batches is shown. Batch 1 shows a uniform PSD with no particles larger than 1 μm in diameter. Batches A and B show a less uniform PSD with two particle size subsets, one in the range of 0.1-1 μm and the other in the range of 10-100 μm. When the PSD is uniform and below 1 μm, the product will be more stable, for example, less coalescence of oil droplets will occur.

[0155] This suggests that the type of sterilization process used can influence the final PSD of the enteral medical nutritional composition when no high pressure homogenization step is applied prior to the sterilization process to reduce the PSD of the batch.

[0156] Example 2

[0157] Three liquid enteral medical nutritional compositions were prepared (as described in Example 3) which differed from each other in the type of homogenization applied to emulsify the oil droplets in the oil-in-water emulsion prior to sterilization using DSI.

[0158] Production method

[0159] The preparation method is similar to the method described in Example 1. The emulsification of the oil droplets in step 3) of the method is changed according to the conditions in Table 2. The sterilization treatment described in Example 1 for batch 1 is applied. Samples are taken twice, once after the homogenization step 3) and once after the UHT treatment and high-pressure homogenization. That is, step 6). The PSD of these samples is determined.

[0160] Table 2

[0161] Batch Rotor-stator pipeline mixer speed 2 0rpm 3 3500rpm C 13000rpm

[0162] result

[0163] Figure 2 The PSD of the batches after emulsification (step 3) is shown. The volume-based mode diameter for batch C is about 2.5 μm, while the volume-based mode diameters for batches 2 and 3 are about 5 μm.

[0164] Figure 3 The PSD of the batches after production is complete is shown. All three batches have similar PSDs with a volume-based mode diameter of approximately 0.3 μm.

[0165] This suggests that when DSI is used for the sterilization step, a high pressure homogenization step prior to the sterilization step is not required to obtain a stable final product with a uniform PSD.

[0166] Example 3 - Follow-on Formula

[0167] A shelf-stable liquid follow-on formula intended for infants from 6 to 12 months of age, containing per 100 ml:

[0168] -66kcal;

[0169] - 86 wt.% water;

[0170] - 1.4 wt.% protein, which comprises whey protein and casein in a weight ratio of 1:1;

[0171] -8wt.% digestible carbohydrates, mainly lactose;

[0172] - 3 wt.% of fat, which comprises a blend of different vegetable oils, fish oil as a source of DHA and microbial oil as a source of ARA;

[0173] - 1.8 wt.% of an emulsifier comprising mono- and diglycerides of fatty acids;

[0174] - 0.8 wt.% of non-digestible oligosaccharides, which include long-chain fructooligosaccharides (from Raftiline HP) and trans-galacto-oligosaccharides (from Vivinal GOS) in a weight ratio of 1:9;

[0175] -Minerals, vitamins and other micronutrients consistent with the requirements for infant formula.

[0176] The follow-on formula had a pH of 6.9 and a viscosity of 2 mPa.s at 20°C.

[0177] Example 4 - Medical nutritional composition

[0178] A shelf-stable liquid enteral medical nutritional composition for adults suitable for patients with disease-related malnutrition, each 100 ml comprising:

[0179] -150kcal;

[0180] - 70 wt.% water;

[0181] -5 wt.% protein, which includes caseinate;

[0182] -18 wt.% digestible carbohydrates;

[0183] - 6 wt.% fat, which comprises a blend of different vegetable oils;

[0184] - 0.3 wt.% of an emulsifier comprising lecithin;

[0185] -Minerals, vitamins and other micronutrients.

[0186] The medical nutritional product had a pH of 6.7 and a viscosity of 20 mPa.s at 20°C.

Claims

1. A method for preparing a shelf-stable liquid enteral nutritional composition, the composition comprising, by weight of the composition: - 0.5-13 wt.% protein, wherein the protein comprises up to 7 wt.% whey protein, based on the weight of the composition; -2-10 wt.% oil; -6-30 wt.% digestible carbohydrates; -50-90 wt.% water; The method comprises the following steps: a. Providing an oil-in-water emulsion, wherein the particles in the emulsion have a volume-weighted mode diameter of at least 3 μm; b. sterilizing the emulsion by direct steam injection (DSI) to obtain a sterilized emulsion having an F0 value of at least 3; c. subjecting the sterilized emulsion to high pressure homogenization at a total pressure of at least 200 bar to obtain the nutritional composition, wherein the particles in the nutritional composition have a volume weighted mode diameter of less than 2 μm.

2. The method of claim 1, wherein the oil-in-water emulsion of step a) has a pH higher than 6.

0.

3. The method of claim 1 or 2, wherein the sterilization is accomplished by ultra high temperature (UHT) treatment using DSI.

4. The method of claim 3, wherein the UHT treatment using DSI is performed at a temperature of at least 135°C for 1-20 seconds, provided that the F0 is at least 3.

5. The method according to any one of the preceding claims, wherein the F0 value of the sterilized emulsion is between 3-130.

6. A method as claimed in any one of the preceding claims, wherein step b) is the only sterilisation step in the method.

7. The process as claimed in any one of the preceding claims, wherein the high pressure homogenization in step c) is carried out at a total pressure of 250-1500 bar.

8. The method according to any one of the preceding claims, wherein the oil-in-water emulsion in step a) is prepared by: - providing an aqueous phase comprising water and water-soluble ingredients; - providing an oil phase comprising oil and lipid components; - emulsifying the aqueous phase and the oily phase to obtain an oil-in-water emulsion having particles having a volume weighted mode diameter of at least 3 μm.

9. The method of claim 8, wherein the emulsification is performed under low shear conditions.

10. The process as claimed in claim 9, wherein the emulsification is performed by means of a homogenizer at a total pressure below 150 bar, by means of a pipeline mixer and / or by pipeline dosing of the oil phase into the water phase.

11. The method of any one of the preceding claims, wherein the nutritional composition does not comprise whey protein micelles.

12. The method of any one of the preceding claims, wherein the oil comprises at least 40 wt.% vegetable oil, based on the weight of the oil.

13. The method of any one of the preceding claims, wherein the nutritional composition is selected from an infant formula or a medical nutritional composition.

14. The method of claim 13, wherein the nutritional composition is an infant formula selected from an infant formula, a follow-on formula, or a toddler formula, wherein the nutritional composition comprises, by weight of the composition: - 0.5-3 wt.% protein, wherein the protein comprises up to 2.5 wt.% whey protein, based on the weight of the composition; -2-5 wt.% oil; -6-10 wt.% digestible carbohydrates; -82-90wt.% water The particles in the obtained infant formula have a volume weighted mode diameter of less than 2 μm.

15. The method of claim 13, wherein the nutritional composition is a medical nutritional composition and comprises, by weight of the composition: - 3-13 wt.% protein, wherein the protein comprises up to 7 wt.% whey protein, based on the weight of the composition; -2-12 wt.% oil; -8-30 wt.% digestible carbohydrates; -55-82 wt.% water The particles in the obtained medical nutritional composition have a volume-weighted mode diameter of less than 1 μm.

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