HMO concentrated solution syrup and preparation method thereof

Abstract

The invention provides HMO concentrated solution syrup and a preparation method thereof, and the preparation method of the HMO concentrated solution syrup comprises the following steps: separating and purifying HMO fermentation liquor prepared by a microbial fermentation method, concentrating to 60 wt% or more, cooling to-10-4 DEG C within 0.5-2 hours, maintaining stirring in the cooling process, cooling to a target temperature, and continuously maintaining stirring for 1-4 hours. By improving the preparation method, the stability of the high-concentration HMO concentrated solution syrup in a refrigeration state can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of food, and in particular to an HMO concentrated liquid syrup and a preparation method thereof. Background Art

[0002] HMO (human milk oligosaccharides), whose Chinese name is "breast milk oligosaccharides" or "breast milk oligosaccharides", is the third most abundant solid component in breast milk (after fat and lactose). It has the functions of regulating immunity, helping brain development and regulating intestinal flora, and is helpful for the growth and development of infants and young children.

[0003] In order to add HMO to nutritional compositions, especially infant formula, synthetic HMO is becoming more and more popular. At present, HMO products are usually obtained by converting lactose with microorganisms, and then separated and purified by chromatography, nanofiltration and / or electrodialysis. The final product is dried by solvent crystallization, or concentrated liquid is directly spray-dried, vacuum drum dryer, fluidized bed drying and other drying methods to obtain various crystalline or amorphous powders.

[0004] For dry-mixed downstream application products, HMO in powder form has its application advantages. For more downstream application products with liquid intermediate states, concentrated liquid syrup is a more convenient and economical application form. The osmotic pressure generated by the high concentration of syrup has an inhibitory effect on the growth of microorganisms. If sterilized before storage, the liquid syrup can be stored for 6 to 12 months, which is convenient for storage.

[0005] However, the current HMO concentrated liquid syrup, as shown in CN103797021B, is prone to crystallization and lacks storage stability due to the high concentration of syrup. The stability problem is usually avoided by controlling the concentration of the syrup below 50%. At the same time, the applicant also found in the research process that although the concentrated liquid with a concentration of more than 50% can maintain a completely dissolved state in most process processes, it will crystallize after about seven days of storage during the refrigeration process. Once the crystal nucleus appears, the subsequent crystallization speed will be greatly accelerated, and larger crystal blocks will be produced at the bottom. This phenomenon not only directly affects the convenience of storage and use of the concentrated liquid in the northern region, but also brings higher requirements to the transportation cycle for the transportation that needs to cross a large meridian from south to north, and increases the cost. Summary of the invention

[0006] The invention provides an HMO concentrated liquid syrup and a preparation method thereof, which can prevent the concentrated liquid syrup from forming large crystals in a long-term refrigerated state.

[0007] In a first aspect, the present invention provides a method for preparing HMO concentrated liquid syrup.

[0008] The preparation method provided by the present invention comprises: separating and purifying the HMO fermentation liquid prepared by the microbial fermentation method, concentrating it to more than 60wt%, then cooling it to -10 to 4°C within 0.5 to 2h, maintaining stirring during the cooling process, and continuing to stir for 1 to 4h after cooling to the target temperature.

[0009] Further preferably, in some embodiments of the present invention, the preparation method comprises: separating and purifying the HMO fermentation broth obtained by microbial fermentation, concentrating it to more than 60 wt %, and then cooling it to -10 to 4° C. within 0.5 to 2 h;

[0010] After cooling to the target temperature, increase the temperature by 10-20℃ within 0.5-1h and maintain it for 0-1h, then cool it down to -10~4℃ within 0.5-2h.

[0011] Generally speaking, as the temperature decreases, HMO syrup enters a metastable state from a stable state, in which the solution is easily stimulated to produce a small amount of fine crystals, which are used as crystal nuclei, causing solutes to gather and arrange around the crystal nuclei, and enter a crystal growth state when external conditions change less, so block crystals often appear at the bottom of the container. As the volume of the container increases, the block crystals become more numerous and larger, and increasingly difficult to dissolve. The present invention directly rapidly cools down when the concentrated solution is prepared, so that the solution enters an unstable state, a large amount of crystals are precipitated and converted to a stable state, and then the operation of moderately warming up and then cooling down is performed, which can further control the precipitated crystals to be small and uniform in particle size. At the same time, since the concentrated solution itself has a certain viscosity and the neutral HMO is not charged, the crystals of the concentrated solution can remain in a non-agglomerated state during the subsequent low-temperature storage process.

[0012] In some embodiments of the present invention, stirring is performed during the cooling process at a rotation speed of 100-500 rpm.

[0013] In some embodiments of the present invention, the cooling step includes: firstly quickly reducing the temperature of the feed liquid to room temperature through a heat exchanger, and then cooling it to -10 to 4°C through a jacketed cooling element.

[0014] In some embodiments of the present invention, the purity of the HMO fermentation broth after separation and purification is above 95%. Preferably, the separation and purification step is that the HMO fermentation broth is sequentially subjected to bacterial removal treatment, decolorization treatment, ion exchange desalination treatment and chromatographic separation.

[0015] In some embodiments of the present invention, the concentration is carried out in a falling film evaporator, a rotary evaporator or a multiple effect evaporator, preferably a falling film evaporator.

[0016] Preferably, before the concentration, the feed liquid is first subjected to ultra-high temperature instantaneous sterilization.

[0017] In some embodiments of the present invention, the following steps are used to obtain the concentrated HMO fermentation broth after separation and purification:

[0018] (1) filtering the HMO fermentation broth (HMO mass concentration is about 5%) through a 200 nm filter membrane to remove bacteria and obtain a sterile fermentation broth;

[0019] (2) heating the sterile fermentation liquid obtained in step (1) to 43° C.; adding activated carbon and stirring, filtering to remove the activated carbon and protein, and obtaining a decolorized liquid;

[0020] (3) subjecting the decolorized solution obtained in step (2) to adsorption desalination by a cation exchange resin and an anion exchange resin in sequence to obtain a desalted solution; and concentrating the desalted solution under reduced pressure to obtain a desalted concentrated solution;

[0021] (4) The desalted concentrated solution obtained in step (3) is separated using a styrene polymer gel column and eluted using pure water to obtain an eluate in which the mass concentration of HMO is 5-20%, which is filtered and then subjected to UHT.

[0022] (5) The eluate obtained in step (4) is concentrated to above 60 wt %, and the temperature of the eluate after concentration is 60-70° C.

[0023] In the above technical solution, the HMO fermentation broth is preferably 2′-FL fermentation broth.

[0024] In a second aspect, the present invention provides an HMO concentrated liquid syrup, wherein the mass concentration of HMO is above 70%, the HMO concentrated liquid syrup does not contain genetically engineered microorganisms, nucleic acid molecules derived from genetically engineered microorganisms and proteins, and organic solvents, the purity of the HMO is at least 95%, and 90% of the crystals in the HMO concentrated liquid have a particle size of no more than 150 microns; that is, the crystal particle size D90 in the concentrated liquid is ≤150 microns.

[0025] The purity of the HMO is at least 95%, wherein "purity" refers to the weight of HMO relative to the dry matter or solute in the HMO concentrate syrup.

[0026] Preferably, 90% of the crystals in the HMO concentrate obtained by the optimized preparation method have a particle size no greater than 80 microns, that is, the crystal particle size D90 in the concentrate is ≤ 80 microns.

[0027] As described in the background art, in the prior art, although HMO concentrated liquid syrup with a concentration exceeding 50% can maintain a completely dissolved state in most process processes, it will crystallize after being stored for about seven days during refrigeration (around 0°C). Once crystal nuclei appear, the subsequent crystallization rate will accelerate sharply, and larger crystal blocks will be produced at the bottom, which are difficult to dissolve even by heating. This phenomenon occurs faster in concentrated liquids with higher concentrations, and is more likely to occur in neutral oligosaccharides than in acidic oligosaccharides, thereby limiting the scope of use of HMO concentrated liquid syrup and increasing storage and transportation costs.

[0028] To address this problem, the present invention provides an HMO concentrated liquid syrup, which can achieve good refrigerated stability even at a concentration of 60% or more, or even 70% or more. Specifically, the HMO concentrated liquid syrup can be completely redissolved within 20 minutes after being placed at 0°C for more than one month and the temperature is raised to 30°C. The discovery of this product makes up for the shortcomings of the existing market.

[0029] In some embodiments of the present invention, the HMO is a fucosyl oligosaccharide, a sialyl oligosaccharide, or an oligosaccharide formed by a core sugar chain structure without a fucosyl group or a sialyl group.

[0030] In the present invention, fucosylated oligosaccharides, also referred to as fucosylated oligosaccharides, refer to oligosaccharides having fucose residues, among which the representative substances are 2′-fucosyllactose and 3-fucosyllactose.

[0031] 2′-fucosyllactose (2′-FL) is a trisaccharide structure formed by fucose and lactose. The commercially available substance is usually prepared by microbial fermentation and has the same structure as 2′-fucosyllactose found in human milk.

[0032] 3-fucosyllactose (3-FL) is a trisaccharide structure formed by fucose and lactose, and is an isomer of 2′-fucosyllactose. This substance can be prepared by microbial fermentation and has the same structure as 3-fucosyllactose found in human milk.

[0033] Sialyl oligosaccharides, also known as sialylated oligosaccharides, refer to oligosaccharides having sialic acid residues, among which the representative substances are 3′-sialyl lactose and 6′-sialyl lactose.

[0034] 3′-sialyllactose (3′-SL) is a structure formed by sialic acid and lactose, and is an isomer of 6′-sialyllactose. This substance is prepared by microbial fermentation and has the same structure as 3′-sialyllactose found in human milk.

[0035] 6′-sialyllactose (6′-SL) is a structure formed by sialic acid and lactose, and is an isomer of 3′-sialyllactose. This substance can be prepared by microbial fermentation and has the same structure as 6′-sialyllactose found in human milk.

[0036] Oligosaccharides formed by a core sugar chain structure without fucosyl or sialic acid groups refer to oligosaccharides other than fucosyl oligosaccharides and sialic acid oligosaccharides. Representative substances include lactosyl-N-tetraose or lactosyl-N-tetraose.

[0037] Lactosyl-N-tetraose (LNT) is a tetrasaccharide structure formed by galactose and glucose. It is a representative substance of oligosaccharides with a core sugar chain as the basic structure and no fucosyl or sialic acid groups. This substance can be prepared by microbial fermentation and has the same structure as lactosyl-N-tetraose found in human milk.

[0038] During the research process of the applicant, it was found that neutral oligosaccharides are more likely to cause the crystallization and agglomeration problem described in the invention than acidic oligosaccharides. Therefore, preferably, in some embodiments of the present invention, the HMO is a neutral HMO.

[0039] In the present invention, neutral HMO or neutral oligosaccharide refers to an oligosaccharide that does not have negative charges derived from carboxylic acid groups.

[0040] Further preferably, the HMO is selected from one or more of 2'-fucosyllactose, 3-fucosyllactose, 2',3-bifucosyllactose, lactosyl-N-triose II, lactosyl-N-tetraose, lactosyl-N-neotetraose, lactosyl-N-fucosylpentose I, lactosyl-N-neofucosylpentose, lactosyl-N-fucosylpentose II, lactosyl-N-fucosylpentose III, lactosyl-N-fucosylpentose V, lactosyl-N-neofucosylpentose V, lactosyl-N-bifucosylhexose I, lactosyl-N-bifucosylhexose II, 6'-galactosyl lactose, 3'-galactosyl lactose, lactosyl-N-hexose, and lactosyl-N-neohexose.

[0041] In a third aspect, the present invention provides a nutritional composition comprising the above HMO concentrated liquid syrup.

[0042] In the present invention, the term "nutritional composition" means a composition that provides nutrition to a subject. The nutritional composition is usually taken orally or intravenously, and it usually includes a lipid or fat source and a protein source.

[0043] In a fourth aspect, the present invention provides a food comprising the above HMO concentrated liquid syrup.

[0044] In the present invention, the term "food" is intended to cover any consumable substance. Thus, it may be a product intended for human consumption, in particular an infant formula, a follow-on formula, an infant or young children's food such as infant cereals, etc. In particular, the HMO concentrate syrup of the present invention may be added to an infant formula, dehydrated milk or a cereal mix.

[0045] The present invention provides an HMO concentrated liquid syrup and a preparation method thereof. By improving the preparation method, the stability of high-concentration HMO concentrated liquid syrup under refrigeration is achieved. This discovery overcomes the defects of limited application range and high storage and transportation costs of HMO concentrated liquid syrup, makes up for the market deficiencies, and provides technical support for the development of more downstream products containing HMO. DETAILED DESCRIPTION

[0046] The term "include" or "comprising" in the present invention is an open description containing the specified components or steps described, and other specified components or steps that will not be substantially affected.

[0047] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0048] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "specific implementations", or "some specific implementations" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0049] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased through regular channels.

[0051] Example 1

[0052] This embodiment provides a 2′-fucosyllactose concentrate, and the preparation method thereof is as follows:

[0053] (1) filtering the 2′-fucosyllactose fermentation broth (the mass content of 2′-fucosyllactose is 5%) through a 200 nm filter membrane to remove bacteria and obtain a sterile fermentation broth;

[0054] (2) heating the sterile fermentation liquid obtained in step (1) to 43° C.; adding activated carbon (the mass ratio of activated carbon to sterile fermentation liquid is 6:100), stirring, filtering to remove activated carbon and protein, and obtaining a decolorized liquid;

[0055] (3) subjecting the decolorized solution obtained in step (2) to adsorption desalination by a cation exchange resin and an anion exchange resin in sequence to obtain a desalted solution; and concentrating the desalted solution under reduced pressure to obtain a desalted concentrated solution;

[0056] The cation exchange resin is a strongly acidic styrene-based cation exchange resin 001X7 (Anhui Samsung Resin Company), and the anion exchange resin is a macroporous weakly basic anion exchange resin D315 with a polyacrylic acid skeleton (Anhui Samsung Resin Company);

[0057] The conductivity of the desalted solution is 8 μS / cm, and the mass concentration of 2′-fucosyllactose in the desalted solution is 75 g / L;

[0058] The conductivity of the desalted concentrate is 8 μS / cm;

[0059] (4) separating the desalted concentrated solution obtained in step (3) using a styrene polymer gel column and eluting with pure water to obtain an eluate; wherein the column temperature of the chromatographic column is 55° C.; and the purity of 2′-fucosyllactose in the eluate is 97%;

[0060] The mass content of 2′-fucosyllactose in the eluate is 10%, and the eluate is filtered and then subjected to UHT;

[0061] (5) The eluate obtained in step (4) is concentrated in a falling film evaporator at 65° C. under negative pressure until the mass content of 2′-fucosyllactose is 70%; at this time, the temperature of the obtained feed liquid is 70° C.;

[0062] (6) Cooling the concentrated liquid to 4°C within 2 hours. Specifically, firstly, the liquid temperature is quickly cooled to room temperature by a heat exchanger, and then cooled to 4°C by a jacketed cooling element (the refrigerant temperature is -15°C). During the cooling process, the stirring speed is 200 rpm.

[0063] (7) After cooling to 4° C., the mixture was kept warm and stirred for 2 h at a speed of 200 rpm to obtain a 2′-fucosyllactose concentrate, in which the crystal size D90 was measured to be 145 μm.

[0064] Example 2

[0065] This embodiment provides a 2′-fucosyllactose concentrate, and the preparation method thereof is as follows:

[0066] (1) filtering the 2′-fucosyllactose fermentation broth (the mass content of 2′-fucosyllactose is 5%) through a 200 nm filter membrane to remove bacteria and obtain a sterile fermentation broth;

[0067] (2) heating the sterile fermentation liquid obtained in step (1) to 43° C.; adding activated carbon (the mass ratio of activated carbon to sterile fermentation liquid is 6:100), stirring, filtering to remove activated carbon and protein, and obtaining a decolorized liquid;

[0068] (3) subjecting the decolorized solution obtained in step (2) to adsorption desalination by a cation exchange resin and an anion exchange resin in sequence to obtain a desalted solution; and concentrating the desalted solution under reduced pressure to obtain a desalted concentrated solution;

[0069] The cation exchange resin is a strongly acidic styrene-based cation exchange resin 001X7 (Anhui Samsung Resin Company), and the anion exchange resin is a macroporous weakly basic anion exchange resin D315 with a polyacrylic acid skeleton (Anhui Samsung Resin Company);

[0070] The conductivity of the desalted solution is 8 μS / cm, and the mass concentration of 2′-fucosyllactose in the desalted solution is 75 g / L;

[0071] The conductivity of the desalted concentrate is 8 μS / cm;

[0072] (4) separating the desalted concentrated solution obtained in step (3) using a styrene polymer gel column and eluting with pure water to obtain an eluate; wherein the column temperature of the chromatographic column is 55° C.; and the purity of 2′-fucosyllactose in the eluate is 97%;

[0073] The mass content of 2′-fucosyllactose in the eluate is 20%, and the eluate is filtered and then subjected to UHT;

[0074] (5) The eluate obtained in step (4) was concentrated in a rotary evaporator at a negative pressure of -0.1 MPa until the mass content of 2′-fucosyllactose was 75%, and the temperature of the obtained feed solution was 65° C.;

[0075] (6) Cooling the concentrated liquid to 0°C within 2 hours. Specifically, firstly, the liquid temperature is quickly cooled to room temperature by a heat exchanger, and then cooled to 0°C within 2 hours by a jacketed cooling element (the refrigerant temperature is -15°C). During the cooling process, the stirring speed is 200 rpm.

[0076] (7) After cooling to 0°C, the temperature was raised to 10°C within 1 hour, and then cooled to 0°C within 2 hours. The stirring speed during the cooling process was 200 rpm to obtain a 2′-fucosyllactose concentrate, in which the crystal particle size D90 was measured to be 55 μm.

[0077] Example 3

[0078] This embodiment provides a 2′-fucosyllactose concentrate, and the preparation method thereof is as follows:

[0079] Steps (1) to (4) are the same as steps (1) to (4) of Example 2;

[0080] (5) The eluate obtained in step (4) was concentrated in a rotary evaporator at a negative pressure of -0.1 MPa until the mass content of 2′-fucosyllactose was 75%, and the temperature of the obtained feed solution was 60° C.;

[0081] (6) Cooling the concentrated liquid to 4°C within 1 hour. Specifically, firstly, the liquid temperature is quickly cooled to room temperature by a heat exchanger, and then cooled to 4°C within 1 hour by a jacketed cooling element (the refrigerant temperature is -15°C). During the cooling process, the stirring speed is 200 rpm.

[0082] (7) After cooling to 4° C., the temperature was raised to 15° C. within 1 h, and then cooled to 4° C. within 1 h. During the cooling process, the stirring speed was 200 rpm to obtain a 2′-fucosyllactose concentrate, in which the crystal particle size D90 was measured to be 68 μm.

[0083] Comparative Example 1

[0084] This comparative example provides a 2′-fucosyllactose concentrated solution (concentration of 70%) prepared by a conventional method, that is, relative to Example 1, after obtaining the concentrated solution in step (5), no other process operations are performed and the solution is naturally cooled to room temperature.

[0085] Comparative Example 2

[0086] This comparative example provides a 2′-fucosyllactose concentrate (concentration of 70%) prepared by a conventional method, that is, relative to Example 1, after the concentrate is obtained in step (5), it is naturally cooled to room temperature and then placed in a non-rapid cooling environment at 4°C for storage.

[0087] Effect comparison

[0088] 1 L of the 2′-fucosyllactose concentrated solution obtained in each example and comparative example was sampled and placed in a glass jar at 0° C. for two months.

[0089] 1. It was observed that there were no agglomerated crystals at the bottom of the concentrated solutions of Examples 1, 2, and 3. The fine crystals at the bottom of Example 1 could be easily shaken apart, and Examples 2-3 only had a turbid appearance.

[0090] However, the concentrated solutions of Comparative Examples 1 and 2 had crystals in the bottom that were in blocks and could not be dispersed.

[0091] 2. Solubility

[0092] The concentrated solutions obtained in Examples 1, 2 and 3 were heated in a water bath to 30° C., maintained for 10 min, and stirred at 50 rpm, during which they were completely dissolved.

[0093] The concentrates of Comparative Examples 1 and 2 could not be completely dissolved when heated to 30° C. in a water bath for 20 min and stirred at 50 rpm. They were completely dissolved after continuous stirring for 40 min.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing HMO concentrated liquid syrup, characterized in that: include: The HMO fermentation liquid prepared by the microbial fermentation method is concentrated to more than 60wt% after separation and purification, and then cooled to -10-4°C within 0.5-2h, and stirring is maintained during the cooling process. After cooling to the target temperature, stirring is continued for 1-4h.

2. The method for preparing HMO concentrated liquid syrup according to claim 1, characterized in that: The preparation method comprises: separating and purifying the HMO fermentation liquid obtained by microbial fermentation, concentrating the liquid to more than 60 wt%, and then cooling the liquid to -10 to 4°C within 0.5 to 2 hours; After cooling to the target temperature, increase the temperature by 10-20°C within 0.5-1h and maintain it for 0-1h, then cool it down to -10~4°C within 0.5-2h.

3. The method for preparing HMO concentrated liquid syrup according to claim 1 or 2, characterized in that: Stirring was performed during the cooling process at a speed of 100-500 rpm.

4. The method for preparing HMO concentrated liquid syrup according to claim 1 or 2, characterized in that: The cooling step includes: firstly quickly cooling the temperature of the feed liquid to room temperature through a heat exchanger, and then cooling it to -10 to 4°C through a jacketed cooling element.

5. The method for preparing HMO concentrated liquid syrup according to claim 1 or 2, characterized in that: After separation and purification, the purity of the HMO fermentation liquid is above 95%. Preferably, the separation and purification step comprises the following steps: the HMO fermentation liquid is sequentially subjected to bacterial removal treatment, decolorization treatment, ion exchange desalination treatment and chromatographic separation; Preferably, before the concentration, the feed liquid is first subjected to ultra-high temperature instantaneous sterilization.

6. A HMO concentrated liquid syrup, characterized in that: wherein the mass concentration of HMO is above 60%, the HMO concentrate syrup does not contain genetically engineered microorganisms, nucleic acid molecules derived from genetically engineered microorganisms and proteins, and organic solvents, the purity of the HMO is at least 95%, and 90% of the crystals in the HMO concentrate have a particle size of no greater than 150 microns; Preferably, 90% of the crystals in the HMO concentrate have a particle size no greater than 80 microns.

7. The HMO concentrated liquid syrup according to claim 6, characterized in that The HMO concentrated liquid syrup is placed at 0°C for more than one month, and can be completely redissolved within 20 minutes when the temperature is raised to 30°C, and the redissolution process includes stirring.

8. The HMO concentrated liquid syrup according to claim 6 or 7, characterized in that: The HMO is a fucosyl oligosaccharide, a sialic acid oligosaccharide, or an oligosaccharide formed by a core sugar chain structure without a fucosyl group or a sialic acid group; Preferably, the HMO is a neutral HMO; More preferably, it is selected from one or more of 2'-fucosyllactose, 3-fucosyllactose, 2',3-bifucosyllactose, lactosyl-N-triose II, lactosyl-N-tetraose, lactosyl-N-neotetraose, lactosyl-N-fucosylpentose I, lactosyl-N-neofucosylpentose, lactosyl-N-fucosylpentose II, lactosyl-N-fucosylpentose III, lactosyl-N-fucosylpentose V, lactosyl-N-neofucosylpentose V, lactosyl-N-bifucosylhexose I, lactosyl-N-bifucosylhexose II, 6'-galactosyl lactose, 3'-galactosyl lactose, lactosyl-N-hexose and lactosyl-N-neohexose.

9. A nutritional composition, characterized in that The HMO concentrated liquid syrup comprises the HMO concentrated liquid syrup according to any one of claims 6 to 8.

10. A food, characterized in that The HMO concentrate syrup comprising any one of claims 6 to 8; Preferably, the food is infant formula.