阅读说明：本技术 天然风味物基料以及用于其制备的方法 (Natural flavour base and method for its preparation ) 是由 张智翠 A·N·仇 J·科勒 M·杰伦安德烈 H·乌尔默 于 2018-05-02 设计创作，主要内容包括：本发明涉及用于制备天然风味物基料的方法和能够通过所述方法获得的风味物基料。本发明的另一方面是用于为食物或饮料产品提供天然坚果风味香韵、天然烘培风味香韵和/或天然焦糖风味香韵的方法。(the present invention relates to a process for preparing a natural flavour base and to a flavour base obtainable by said process. Another aspect of the invention is a method for providing a natural nut flavor note, a natural baked flavor note, and/or a natural caramel flavor note to a food or beverage product.)

1. A process for preparing a natural flavor base composition, the process comprising the steps of:

-culturing a bacterial strain in a culture medium to produce and accumulate L-ornithine and/or a derivative thereof in the culture medium to a concentration of at least 1.0% by weight of the culture medium;

-isolating the bacterial strain from the culture medium, optionally after the culturing step;

-optionally concentrating the culture medium after the culturing step;

-adding a reducing sugar to the culture medium after the culturing step;

-thermally reacting the medium at a temperature of 75 ℃ to 170 ℃ for at least 5 minutes after addition of the reducing sugar;

-concentrating the culture medium, optionally after the thermal reaction step, by evaporation or spray drying;

Wherein the reducing sugar is added to the medium in an amount of sugar ornithine in a ratio of 1:5 to 10:1 (w/w).

2. the method of claim 1, wherein the bacterial strain belongs to a genus selected from the group consisting of: corynebacterium (Corynebacterium), Arthrobacter (Arthrobacter), Brevibacterium (Brevibacterium), Bacillus (Bacillus) or Microbacterium (Microbacterium).

3. The method according to claim 1 or 2, wherein culturing the bacterial strain produces and accumulates L-ornithine and/or a derivative thereof to a concentration of at least 1.5% by weight, preferably at least 2.0% by weight, more preferably at least 5% by weight of the culture medium.

4. The method according to one of claims 1 to 4, further comprising a step of heat-inactivating the bacterial strain after the culturing step.

5. The method according to one of claims 1 to 4, wherein separating the bacterial strain from the culture medium is achieved by sedimentation, centrifugation and/or filtration.

6. The method according to one of claims 1 to 5, wherein concentrating the culture medium after the culturing step is achieved by partial or total evaporation of the water present in the culture medium.

7. The method according to one of claims 1 to 6, wherein the reducing sugar is selected from glucose, xylose, ribose, rhamnose, fructose, maltose, lactose, arabinose or a combination thereof.

8. The process according to one of claims 1 to 7, wherein the thermal reaction step is at a temperature of from 85 ℃ to 150 ℃, preferably from 95 ℃ to 130 ℃.

9. The method according to one of claims 1 to 8, wherein the culture medium is dried to a powder after the thermal reaction step.

10. Natural flavour base obtainable by a process according to one of claims 1 to 9.

11. Use of the natural flavor base of claim 10 for adding a nut, baked and/or caramel flavor note to a food product.

12. The use according to claim 11, wherein the food product is selected from the group consisting of culinary soups, noodles, broths, sauces, dressings, ready-to-eat meal preparations, instant and ready-to-drink beverage preparations, cookies, cakes, snacks, dough products and crackers, ice cream and frozen confections, chilled dairy products, milk powder compositions, dairy beverages and dessert preparations.

13. Use according to claim 12, wherein the culinary soup, bouillon, sauce or seasoning is in the form of a powder, liquid, granulated product, tablet or paste.

14. The use of claim 13, wherein the ready-to-eat meal preparation, snack or dough product is frozen.

15. a method for providing a food or beverage product with a natural nut flavor note, a natural baked flavor note, and/or a natural caramel flavor note, the method comprising the step of adding the natural flavor base of claim 10 to a formulation of the food or beverage product.

Technical Field

The present invention relates to a process for preparing a natural flavour base and to a flavour base obtainable by said process. A further aspect of the invention is a method for providing natural nut flavor notes to a food product.

Background

Additives such as purified amino acids, vitamins or flavour molecules are often used to enhance the flavour reactants in food products and the body notes (bodies) and taste in compositions. However, a problem with the use of these additives is that they are not considered natural, as they are usually obtained first by purification or chemical synthesis involving one or more non-natural processing steps, such as elution from impurities using a chemical eluent, or chemical synthesis reactions.

Natural flavor standards of various countries including europe determine that flavors will be made only of natural components, but flavors made by performing chemical processes or adding other components are determined to be non-natural flavors. One example is a process for the preparation of L-cysteine by two steps (fermentation and chemical reduction). For this reason, it is desirable to have a flavor component that is prepared using only natural processes such as fermentation and omitting any chemical production steps.

WO2009/040150 discloses natural shelf stable taste enhanced savoury bases (savoury bases) produced by fermentation using microorganisms of the genus Corynebacterium (Corynebacterium), Brevibacterium (Brevibacterium) or Bacillus (Bacillus). The savoury base comprises naturally derived compounds such as glutamate, Inosine Monophosphate (IMP) and Guanosine Monophosphate (GMP) in an amount between 10 and 80 wt%; and further naturally derived compounds selected from the group consisting of organic acids, amino acids, peptides and aroma compounds; and a low fat content of the savoury base in the range of 0 to 15 wt%. The disclosed salty base improves umami taste in food products. However, it does not provide a top note in itself.

EP0357812 describes a process for improving the flavour of a protein product derived from a microorganism, which process comprises culturing the microorganism in the presence of a flavour enhancing additive, heat treating the resulting fermentation and then drying the fermentation in the absence of centrifugation. Examples of flavor enhancing additives added during fermentation are animal by-products (beef extract, pork extract or chicken extract) or fatty acids produced by adding dairy precursors and lipases. The additive is used at 0.5 to 5% by weight. In this case, the aim is to produce a protein-rich foodstuff, rather than an intermediate component rich in precursors that can be used in subsequent flavour reactions.

yeast extract can be added to food products as a source of natural amino acids, and/or used in thermal reaction flavor processes. An example is provided in US 4,879,130. However, the use of yeast extracts often adds a typical yeast note or off-flavor to such flavor bases and food products. This is generally not preferred by many consumers, particularly in europe and the united states.

EP 0139592a2 describes plants which produce amino acids such as ornithine by fermentation. The production of amino acids is carried out by fermenting strains such as Corynebacterium melassecola (Corynebacterium melassecola) or Corynebacterium glutamicum (Corynebacterium glutamicum) in a fermentation medium.

CN 101235401a describes a method for the preparation of L-amino acids such as ornithine by fermentation. The process of the invention uses the fermentation additive phosphobetaine.

In an article entitled "Metabolic engineering of Corynebacterium glutamicum for the production of L-ornithine" [ biotechnological and bioengineering ] 2015, 112 (2): 416-421 pages, Kim et al ], Metabolic engineering of Corynebacterium glutamicum ATCC 13032 for the production of L-ornithine is disclosed in a number of industrial applications in the food industry.

Accordingly, there remains a need in the art and in the food industry to provide new methods for preparing flavor base compositions that can provide flavor bases that are perceived by consumers as absolutely natural, and at the same time can also provide new and more complete and authentic flavor profiles and flavor headnotes.

Disclosure of Invention

it is an object of the present invention to improve the prior art and to provide a new process for preparing a natural flavour base which is perceived by the consumer as all natural and which provides an improved and all natural flavour profile to a food product. A further object of the present invention is a method for providing a natural and authentic nut flavor note to a food, beverage or flavored product.

The object of the invention is achieved by the subject matter of the independent claims. The dependent claims further develop the idea of the invention.

Accordingly, the present invention provides in a first aspect a process for preparing a natural flavour base composition, the process comprising the steps of:

-culturing the bacterial strain in a culture medium to produce and accumulate L-ornithine and/or a derivative thereof in the culture medium to a concentration of at least 1.0% by weight of the culture medium;

-optionally isolating the bacterial strain from the culture medium after the culturing step;

-optionally concentrating the culture medium after the culturing step;

-adding a reducing sugar to the culture medium after the culturing step;

-thermally reacting the medium at a temperature of 75 ℃ to 170 ℃ for at least 5 minutes after addition of the reducing sugar;

-concentrating the culture medium, optionally after the thermal reaction step, by evaporation or spray drying.

In a second aspect, the present invention relates to a natural flavour base obtainable by the process of the present invention.

a third aspect of the invention relates to the use of the natural flavour base of the invention for adding a nut, bakery and/or caramel flavour note to a food product.

Yet another aspect of the invention is a method for providing a natural nut flavor note, a natural baked flavor note, and/or a natural caramel flavor note to a food product, the method comprising the step of adding the natural flavor base of the invention to the formulation of the food product.

The present inventors have found that a culture of a bacterial strain, such as e.g. corynebacterium glutamicum, cultured in such a way or conditioned in such a way that L-ornithine is overproduced, can be used directly in a thermal reaction process to produce a salty flavour base which is perceived by the consumer as all natural and which has unexpectedly improved nut flavour characteristics even compared to prior art salty flavour bases. For this new process, the bacterial culture may be performed such that the bacterial cells are not separated from the culture medium after the fermentation step, or alternatively, the bacterial cells may first be removed from the culture medium after fermentation by sedimentation, centrifugation and/or filtration. The culture medium may then be concentrated to remove a substantial amount of the water present in the culture medium for ease of further processing. Thus, for example, a paste of concentrated medium with a residual moisture content of only about 5 to 40 wt.% can be obtained. A reducing sugar, such as glucose, can then be added to the concentrated medium and the mixture further processed by thermally reacting the mixture at a temperature above 75 ℃, preferably above 85 ℃. This thermally induced chemical reaction is also well known under the term maillard reaction. Optionally, the end product of the reaction may then be further concentrated, for example, to a paste, or dried to a powder.

The present inventors have surprisingly found that when using this method, a natural flavour base composition can be produced having a significantly improved nut flavour note compared to prior art methods which either utilize only conventional non-conditioned bacterial fermentation media, such as described in, for example, WO2009/040150, or by using isolated purified L-ornithine in a maillard reaction model system. Evidence of which is provided in the examples section herein below. Thus, the present invention provides a new process which has the advantage of being absolutely natural, i.e. without the use and addition of separate chemicals or molecules, relatively cheap and suitable for large-scale industrial application, and which provides an even better nut flavour profile to the resulting flavour base composition.

Drawings

FIG. 1: sensory evaluation of samples 1 to 4 is described in examples 1 to 6.

Detailed Description

The present invention relates to a process for preparing a natural flavor base composition comprising the steps of:

-culturing the bacterial strain in a culture medium to produce and accumulate L-ornithine and/or a derivative thereof in the culture medium to a concentration of at least 1.0% by weight of the culture medium;

-optionally isolating the bacterial strain from the culture medium after the culturing step;

-optionally concentrating the culture medium after the culturing step;

-adding a reducing sugar to the culture medium after the culturing step;

-thermally reacting the medium at a temperature of 75 ℃ to 170 ℃ for at least 5 minutes after addition of the reducing sugar;

-concentrating the culture medium, optionally after the thermal reaction step, by evaporation or spray drying.

The term "natural" in the present invention means "made by natural production", i.e. the flavour base composition is made only by fermentation and heat treatment. Thus, "natural" also means that the flavor base composition does not contain artificial chemical compounds (such as synthetically produced and/or chemically purified molecules) and that the flavor base composition is not made by the addition of artificial chemical compounds (such as synthetically produced and/or chemically purified molecules). Examples of such undesired molecules are flavour compounds, colouring agents, antimicrobial compounds, vitamins, amino acids, organic acids, alcohols and esters.

"culturing bacterial strains" by fermentation. Typically, this fermentation is submerged and carried out in a closed or open fermentation reactor. The choice and composition of the medium depends on the choice of the bacterial strain chosen for the production and accumulation of L-ornithine and/or derivatives thereof in said medium. In general, the skilled worker familiar with the fermentation process of the selected bacterial strain knows and can readily compound media suitable for the respective cultivation process.

Preferably, the bacterial strain used in the method of the invention belongs to a genus selected from the group consisting of: corynebacterium, Arthrobacter, Brevibacterium, Bacillus or Microbacterium.

in a preferred embodiment, the cultivation of the bacterial strain produces and accumulates L-ornithine and/or a derivative thereof to a concentration of at least 1.5%, more preferably at least 2.0%, even more preferably at least 2.5% by weight of the culture medium. More preferably, the concentration of L-ornithine and/or derivatives thereof is even higher than 3%, 4%, 5% or even 10% by weight of the culture medium.

In one embodiment, the method of the present invention further comprises the step of heat inactivating the bacterial strain after the culturing step. This heat inactivation is carried out after the termination of the fermentation process, i.e. at the end of the growth phase of the bacterial cells in the culture medium, and leads to an inactivation of the viability of the bacterial cells, including the inactivation of the enzymes that have been released or that are still contained within the bacterial cells. Heat inactivation can potentially prevent degradation of complex compositions of the culture medium after the culturing step, e.g., uncontrolled further growth and/or metabolism of bacteria and/or uncontrolled further activity of certain enzymes.

In another embodiment, the bacterial strain is isolated from the culture medium after the culturing step, i.e. after the fermentation process. Isolation of the bacterial strain from the culture medium can generally be achieved by sedimentation, centrifugation and/or filtration. An advantage of this embodiment may be that further processing of the culture medium in the method of the invention is easier in an industrial environment. Furthermore, there is a reduced risk that the bacterial strain may reduce the quality of the obtained medium after the fermentation process has been terminated.

In another embodiment, the culture medium may be concentrated after the culturing step. This may be done with or without prior isolation of the bacterial strain from the culture medium. Thus, the concentrated medium according to this embodiment may or may not comprise bacterial cells. Preferably, concentration of the culture medium after the culturing step is achieved by partial or total evaporation of the water present in the culture medium. Preferably, the resulting concentrated medium is in the form of a paste. Such pastes may still have a moisture content of 5 to 40 wt.%, preferably 15 to 35 wt.%. One of the advantages of this embodiment is that it allows the thermochemical reaction step to be carried out in a more concentrated form together with the reducing sugar. The efficiency and yield of such chemical reactions will be greatly increased.

In one embodiment of the invention, the reducing sugar added to the culture medium after the termination of the culturing step is a monosaccharide containing 4, 5 or 6 carbon atoms. Alternatively, disaccharide reducing sugars can also be used. Preferably, the reducing sugar is selected from glucose, xylose, ribose, rhamnose, fructose, maltose, lactose, arabinose or a combination thereof. The most preferred sugar is glucose. In one embodiment, reducing sugars are added as a sweetener composition, such as malt extract or syrup.

In one embodiment of the process of the invention, the reducing sugar is added to the medium in an amount of sugar ornithine in a ratio of 1:5 to 10:1(w/w), preferably in an amount of sugar ornithine in a ratio of 1:1 to 5:1 (w/w). Ratio sugar ornithine is understood to be the (weight/weight) ratio of reducing sugars to L-ornithine and/or derivatives thereof. The present inventors have found that within this ratio range, the addition of reducing sugars to the medium after the cultivation step provides the best results with respect to producing typical desirable nut flavor profiles during the following chemothermal reactions.

the method of the present invention comprises the step of thermally reacting the medium at a temperature of 75 ℃ to 170 ℃ for at least 5 minutes, preferably at least 10 minutes after adding the reducing sugar. This step is a chemical reaction step between the different components present in the culture medium after the addition of reducing sugars, and it is thermally induced. This thermal reaction step is also commonly referred to as a maillard reaction. During this thermal reaction step, different precursor molecules from the culture medium chemically react, for example with reducing sugars, thereby generating new flavour and taste active molecules. Finally, the overall effect of the selected media of the present invention together with reducing sugars is to provide the new and improved flavor profile of the natural flavor base after the heat-induced reaction step.

Preferably, the thermal reaction step of the process of the invention is at a temperature of from 85 ℃ to 150 ℃, more preferably from 95 ℃ to 130 ℃.

In another embodiment of the invention, the medium is dried to a powder after the addition of the reducing sugar and after the thermal reaction step. Drying can be achieved, for example, by spray drying or vacuum drying. The obtained natural flavour base composition may then advantageously be better integrated into non-liquid flavoured products such as for example seasoning powders or seasoning chips.

Another aspect of the invention is a natural flavour base obtainable by the process of the invention. As evidenced by the below, this new natural flavor base has an improved nut flavor note and is therefore distinguishable from similar prior art flavor bases. In particular, the inventors have observed that this new natural flavour base has a further improved caramel, popcorn, biscuit and buttery flavour note compared to the respective reference flavour base product.

another aspect of the invention is the use of the natural flavor base of the invention for adding a nut, baked and/or caramel flavor note to a food product. Preferably, the food product is selected from the group consisting of culinary soups, noodles, broths, sauces, dressings, ready-to-eat meal preparations, instant and ready-to-drink beverage preparations, cookies, cakes, snacks, dough products and crackers, ice cream and frozen confections, refrigerated dairy products, milk powder compositions, dairy beverages, and dessert preparations. Preferably, the culinary soup, bouillon, sauce or seasoning product of the invention is in the form of a powder, liquid, granulated product, tablet or paste. Furthermore, in case the food product is a ready-to-eat meal preparation, a snack or a dough product, the food product is preferably frozen. For example, refrigerated dairy products include fermented milks, cream desserts, or dairy desserts.

Another aspect of the invention is a method for providing a food or beverage product with a natural nut flavor note, a natural baked flavor note, and/or a natural caramel flavor note, the method comprising the step of adding the natural flavor base of the invention to the formulation of the food or beverage product. Preferably, the method is used to provide a natural nut flavor note to a food or culinary flavoring product.

Those skilled in the art will appreciate that they may freely combine all of the features of the invention disclosed herein. In particular, the features described for the process for preparing the natural flavour base composition of the present invention may be combined with the flavour base obtainable by this process, the use of said flavour base and the method of use of said flavour base, and vice versa. In addition, features described for different embodiments of the invention may be combined.

Further advantages and features of the invention will be apparent from the figures and embodiments.