WO2019234362A1

WO2019234362A1 - Method for producing an emmental aroma

Info

Publication number: WO2019234362A1
Application number: PCT/FR2019/051360
Authority: WO
Inventors: Hubert EUDIER; Jean-Paul LORAND
Original assignee: Onyx Developpement Sas
Priority date: 2018-06-07
Filing date: 2019-06-06
Publication date: 2019-12-12
Also published as: FR3082099B1; FR3082099A1

Abstract

The invention relates to a method for producing an Emmental aroma, characterised in that it comprises the following steps: grinding sorghum seeds (Sorghum bicolor); producing an aqueous suspension comprising the sorghum powder produced in the preceding grinding step and a growth factor selected from the group comprising a yeast extract, a salt, glycerol, an amino acid, a magnesium source, a sulphur source, a calcium source, an oligo element and the mixtures thereof, being preferably a mixture of yeast extract and salt; sterilising the aqueous solution; saccharifying the sterilised suspension produced in the previous step, preferably by enzymatic means, by adding at least two saccharification enzymes; and carrying out propionic fermentation of the suspension produced from the saccharification step, by adding a bacterial strain Propionibacterium freundenreichii, preferably by adding the strain P. freundenreichii subsp shermanii.

Description

Process for the preparation of an emmental flavor

The present invention relates to a method for preparing an emmental flavor.

To date, emmental flavors, in the form of powder or liquid, have been developed to bring a specific emmental flavor to a wide range of food preparations, whether salty or sweet.

However, flavourists are constantly on the lookout for new flavors to be offered to agri-food manufacturers, who respect the authenticity of tastes, culinary values and the balance of the senses.

The plant is in full progression and the tendency of the vegetable on the plate is worldwide. Food is planted for reasons of health, preservation of resources or animal welfare. It is therefore important to have food flavors from the plant.

One of the aims of the invention is to obtain an emmental flavor derived from the plant, not including lactose. Such aroma responds to the name vegan (e).

Another object of the invention is to obtain an Emmental aroma from a plant particularly present in southern countries.

Another object of the invention is to obtain an emmental flavor derived from the plant by propionic fermentation.

The bacteria responsible for the propionic fermentation belong in particular to the genus Propionibacterium. These bacteria play an important role in the ripening of cooked cheese of the Emmental, Gruyère type. Propionic fermentation consists of converting lactic acid into propionic acid (also called propanoic acid), acetic acid and carbon dioxide. Propionic acid and acetic acid are responsible for the special flavor of these cheeses, while the carbon dioxide released causes the appearance of "holes".

The inventors have carried out intensive research on a very large number of plant substrates for the production of an Emmental flavor by propionic fermentation. As a result of these investigations, the inventors surprisingly discovered that sorghum was the only vegetable substrate, among the many tested, which was fermentable for the production of an emmental flavor.

Sorghum (also spelled sorghum), more commonly referred to as common sorghum (scientific name: Sorghum bicolor or Sorghum bicolor (L.) Moench), is a monocotyledonous plant species of the family Poaceae (Gramineae), native to Africa.

Sorghum has the advantage of being widespread in the wild in tropical and subtropical climates. For centuries, people in Africa and Asia have been using their seeds for food.

Today, sorghum is grown on all continents. The species Sorghum bicolor is indeed an important crop at the world level (it is the fifth cereal in the world by the volume of production after maize, rice, wheat and barley), both for human consumption (as cereals or for the production of syrup and molasses), as for animal feed (in the form of green feed, dry straw or cereal concentrate), the production of alcoholic beverages and biofuels. Most varieties are drought and heat tolerant, and are particularly important in arid regions.

To the knowledge of the inventors, the propionic fermentation of sorghum for obtaining an emmental flavor has never been described to date.

The publication of Andrzej Babuchowski et al (1999) " ⁽ teaches the propionic fermentation of cabbage, salad and beetroot.

The publications of Dufour et al (1992) and Filya and al (2003) ⁰ teach fermentation of sorghum to make beer or silage.

The propionic fermentation of sorghum, however, has never been described.

The present invention relates to a method for preparing an emmental flavor, characterized in that it comprises the following steps:

- milling sorghum seeds (Sorghum bicolor);

- Preparation of an aqueous suspension comprising the sorghum powder as obtained at the end of the preceding grinding step and a growth factor selected from the group comprising a yeast extract, a salt, glycerol, an acid amine, a source of magnesium, a source of sulfur, a source of calcium, trace elements and mixtures thereof, and is preferably a mixture of yeast extract and salt;

sterilization of the aqueous suspension;

saccharification of the sterilized suspension obtained at the end of the preceding step, preferably enzymatically by adding at least one saccharification enzyme,

propionic fermentation of the suspension obtained at the end of the saccharification step, by addition of a bacterial strain Propionibacterium freundenreichii, preferably by addition of the strain P. freundenreichii subsp shermanii.

The sorghum used in the process of the invention is selected from the group consisting of red sorghum, white sorghum and mixtures thereof.

According to the invention the sorghum used may be forage sorghum or non-fodder, from any variety of Sorghum and any geographical area, including Burkina Faso or France.

In order to facilitate the fermentation, the sorghum seeds are crushed dry until a fine powder is obtained. The particle size must be sufficiently fine so that a homogeneous suspension can then be produced, but not too fine either.

According to an advantageous embodiment of the process of the invention, the step of grinding the sorghum seeds is carried out, preferably dry, until a powder having a particle size ranging from 0.5 to 1.5 is obtained. mm, preferably from 0.8 to 1.2 mm.

The particle size is measured using an optical microscope (x40 magnification).

The resulting sorghum powder is mixed with water to form an aqueous suspension. One or more growth factors are added to the aqueous suspension.

According to another advantageous embodiment of the method of the invention:

the yeast extract used as a growth factor is chosen from the group comprising that marketed by Springer under the name "Springer® 1501/35-MG-L", "Springer® 4101/0-MG-L", "Springer® Hyp A", "Springer® 0251/0-PW-L", "Springer® 2020 / 0- MG-L ", by Difco under the name" Difco 124-500G ", by Biokar Diagnostics under the name" A1202HA "and mixtures thereof, and is preferably yeast extract" Springer 1501/35-MG-L " ,

the salt used as a growth factor is selected from the group consisting of potassium hydrogen phosphate, ammonium phosphate, monocalcium phosphate, sodium hydrogen phosphate and mixtures thereof, and is preferably potassium hydrogen phosphate,

the amino acid used as a growth factor is selected from the group comprising arginine aspartate, peptone and mixtures thereof,

the source of magnesium used as a growth factor is selected from the group comprising magnesium hydroxide, magnesium chloride and mixtures thereof,

the source of sulfur used as growth factor is chosen from the group comprising ammonium sulphate, sodium sulphate, potassium sulphate, calcium sulphate and their mixtures,

the source of calcium used as a growth factor is chosen from the group comprising calcium chloride, calcium carbonate, calcium sulphate, calcium lactate, calcium gluconate, calcium citrate and their mixtures,

the trace element used as a growth factor is chosen from the group comprising cobalt, zinc, manganese and their mixtures.

According to an advantageous embodiment of the process of the invention, the growth factor is a mixture of a yeast extract and a salt as defined above. Indeed, the most advantageous sensory profiles for the emmental flavor of the invention are obtained with the yeast extract and the salt as defined above.

The preparation process of the invention may advantageously comprise, at the end of the step of preparation of the aqueous suspension as described above, and before the sterilization step, a step of deoxygenation of the aqueous suspension, said deoxygenation step being preferably performed by nitrogenizing said aqueous suspension until the concentration of dissolved oxygen present in the suspension is less than or equal to 5%.

An oxygen concentration of less than or equal to 5% represents sufficient anaerobics to minimize stress during the seeding of the propionic ferments (bacterial strain Propionibacterium freundenreichii), which has the effect of maximizing their survival. This percentage of 5% therefore represents the optimal anaerobic for the growth of microorganisms.

According to the invention, the sterilization step of the aqueous suspension, said aqueous suspension being optionally previously deoxygenated, is carried out at a temperature ranging from 100 ° C. to 140 ° C., for a period ranging from 10 to 30 minutes.

At the end of the sterilization step, the sterilized suspension is saccharified. Saccharification is a process that transforms complex sugars, such as starch or cellulose, into simpler sugars, such as glucose and fructose.

The saccharification step can be carried out enzymatically or chemically.

The chemical route uses acid hydrolysis of starch by hydrochloric acid or sulfuric acid (Wang et al, 2015) ⁽⁴⁾ . This method is however quite expensive and requires a buffering step and then purification because the mixture obtained is rich in salt (NaCl, KCl, K ₂ SO ₄ or Na ₂ SO ₄ ).

The enzymatic route, which is that chosen in the context of the process of the invention, is more advantageous than the chemical route, because it is faster, less expensive and more environmentally friendly.

According to one embodiment of the invention, the saccharification of the sterilized suspension is carried out by adding at least one saccharification enzyme. In particular, the saccharification enzyme makes it possible to hydrolyze the starch naturally present in sorghum in glucose.

According to an advantageous embodiment of the method of the invention, the saccharification enzyme added to the sterilized suspension comprises an alpha-amylase and a glucoamylase, preferably in a 1: 1 ratio, said enzyme of saccharification is preferably a mixture of two enzymes marketed by Lyven under the name "Amylyve A30" and "Amylyve AG300".

Once the saccharification enzyme (s) has been added, the propionic fermentation step can begin. The propionic fermentation may begin even if the saccharification is not yet complete.

According to an advantageous embodiment of the invention, the bacterial strain Propionibacterium freundenreichii subsp shermanii added to the suspension to initiate the propionic fermentation is preferably that marketed by Danisco under the name "Choozit Eyes 2 Lyo 2D".

The latter is preferably added in an amount ranging from 0.02% to 0.50% w / w, preferably about 0.07% w / w, the percentage representing the mass of added bacterial strain relative to the total mass of the suspension.

According to the preparation method of the invention, the propionic fermentation step is carried out at a temperature ranging from 28 ° C to 34 ° C, for a time ranging from 68 hours to 76 hours, and preferably for 72 hours.

At the beginning of the propionic fermentation step, the pH is not corrected and fermentation begins at a pH of 5.5 to 6.

The pH at a value of 5 to 7 corresponds to the optimal conditions of culture of the seeded bacterial strain.

Then, during the fermentation step, the pH is neutralized continuously at a value corresponding to the optimal conditions of culture, by adding a compound selected from the group comprising ammonia (NH ₃ ), sodium hydroxide (NaOH ), potassium hydroxide (KOH), calcium carbonate (CaCCL) and mixtures thereof, and is preferably ammonia.

During the propionic fermentation, the glucose (obtained during the enzymatic hydrolysis of the starch) is converted into propionic acid and acetic acid, which in particular represent the molecules of interest of the emmental flavor.

By "flavor" is meant the sensation jointly caused by the taste and smell of a food. Thus, at the end of the propionic fermentation step, a fermented suspension, more particularly known as "fermentation wort", with an emmental flavor, which notably comprises:

propionic acid, in an amount ranging from 0.7% to 0.9% w / w, preferably from 0.78% to 0.82% w / w,

acetic acid, in an amount ranging from 0.1% to 0.3% w / w, preferably from 0.18% to 0.22% w / w,

said percentages being percentages by weight relative to the total mass of the fermentation must.

However other compounds are also present in the fermentation must, such as ethanol, lactic acid, residual glucose, residual dextrins, fatty acids, fumarate, glutamate, aspartate, succinate , carbon dioxide, butyric acid, hexanoic acid, acetoin, 1,2-propanediol, ethanal and 2-butanone.

The emmental flavor present in the fermentation must is certainly caused by the propionic acid and acetic acid molecules, but also by the alchemy between these molecules and the other compounds present in the fermentation must obtained from sorghum.

The fermentation must obtained according to the process of the invention may also be fractionated and then dried.

The preparation process of the invention also comprises, at the end of the propionic fermentation step, the following steps:

fractionation of the fermentation broth obtained at the end of the fermentation stage, said fractionation being preferably carried out by centrifugation,

recovery of the supernatant harvested at the end of the fractionation step of the fermentation must,

drying the supernatant thus recovered,

recovery of Emmental aroma which is in pulverulent form.

The fractionation described in the above embodiment was carried out by centrifugation, after which two fractions were obtained: the supernatant, which is the desired product, and a pellet that is composed of bacteria and insoluble matter (fibers).

However, said fractionation could also be carried out by filtration, microfiltration, ultrafiltration or by sedimentation by gluing (aggregation by the action of a coagulating agent).

According to one embodiment of the invention, the supernatant recovered at the end of the fractionation stage is placed, before drying, on an aroma carrier chosen from the group comprising maltodextrin, modified starches, flours, dextrins, cyclodextrin and mixtures thereof, and is preferably maltodextrin.

Advantageously, the amount of aroma carrier, and preferably maltodextrin, relative to the supernatant recovered at the end of the fractionation step is twice the percentage of solids of said supernatant.

As an indication, the supernatant recovered at the end of the fractionation step (hereinafter referred to as "supernatant") has a percentage of solids ranging from 2% to 8%, preferably from 4% to 6%, and more preferably still 4 to 5%.

The supernatant, which has preferably been arranged on a flavor carrier, is dried, preferably with the aid of an atomizer dryer.

The drying temperature is preferably 220 ° C to 320 ° C. The drying rate is preferably from 1 L / h to 3 L / h.

At the end of the supernatant drying step, the emmental flavor which is in the form of a powder is thus recovered.

According to an advantageous embodiment of the process of the invention, said emmental flavor, which is in pulverulent form, comprises:

a quantity of propionic acid ranging from 3% to 4% w / w, preferably from 3.4% to 3.6% w / w,

an amount of acetic acid ranging from 0.4% to 1.3% w / w, preferably from 0.7% to 1.0%, and even more preferably from 0.8% to 0.9% m / m, said percentages being percentages by weight relative to the total mass of the emmental flavor in powder form.

The powder has a particle size ranging from 1 mHi to 1500 mAH, the particle size being measured using an optical microscope (magnification × 40).

Another subject of the present invention is an emmental flavor that can be obtained according to the process as defined above.

The invention also relates to the use of an emmental flavor, as defined above or as obtained according to the method of the invention, in food preparations, salted or sweetened.

The following examples illustrate the invention, they do not limit it in any way.

Example 1

Vegetable substrates tested

Many plant substrates comprising starch (starch substrates) have been tested by the inventors, such as, for example, peanut, corn starch, de-limed soybean, coral lentils, cassava flour, néré flour, white rice, and soya milk. , canned corn, beet molasses, rice flour, millet flour, white sugar, mixtures such as coral / peanut (50:50), soy / peanut (50:50) (25: 75) (75: 25), néré / peanut (50:50) etc.

For testing, these starchy substrates were compared to control substrates that mimic the usual conditions for seeding propionic bacteria, namely the following substrates: lactic acid, calcium lactate, cow's milk and mozarella.

The purpose of the tests conducted by the inventors was to determine whether these starch substrates, once hydrolyzed to glucose, led to the same results as the propionic fermentation of glucose indicated in the state of the art.

Contrary to the expectations of the inventors, the latter found that these substrates, and especially those particularly rich in starch, led after fermentation to flavors of emmental flavor but with other notes. unwanted aromas such as notes of sulfur, ammonia, vegetal notes etc.

Without wishing to be bound by any theory, the inventors are of the opinion that the aromatic notes other than emmental are in particular due to the variable content in protein content of the different substrates, to the presence of different trace elements, etc. . These results confirm that the propionic fermentation for obtaining an emmental flavor depends on all the compounds present in the substrate and not exclusively carbohydrates.

The inventors, after much additional research on other substrates, have surprisingly discovered that sorghum makes it possible to obtain a fermentation broth with emmental flavor without aroma defects in comparison with other substrates.

Example 2

Preparation of an emmental flavor

The seeds used come from red sorghum (Sorghum bicolor).

The seeds are crushed to dryness until a sorghum powder with a particle size of about 1 mm is obtained. The particle size was measured by light microscopy (x40 magnification).

An aqueous suspension is then prepared which comprises:

sorghum powder in an amount of 100 g / L,

a yeast extract "Springer® 1501/35-MG-L" in an amount of 10 g / L,

potassium hydrogen phosphate in an amount of 0.25 g / l.

The total volume of the aqueous suspension is 3L.

The suspension is put under nitrogen to obtain an amount of dissolved oxygen of less than or equal to 5% during the fermentation.

Sterilization is performed at a temperature of 120 ° C for 20 minutes. The hydrolysis of sorghum is carried out with two Lyven enzymes: "Amylyve A30®" (alpha-amylase: 0.035% w / w, the percentage being a percentage by mass relative to the total mass of the sterilized suspension) and "Amylyve" AG300® (glucoamylase, 0.035% w / w). The propionic fermentation is initiated by seeding the strain Propionibacterium freundenreichii subsp shermanii distributed by Danisco under the name "Choozit Eyes 2 Lyo 2D". The seeded dose is 0.07% w / w.

The propionic fermentation step is carried out in a bioreactor or in a closed container. At the beginning of fermentation, the pH is not corrected and fermentation begins between pH 5.5 and 6. The neutralization is continuous with 32% ammonia. The advantage of using ammonia is that excess evaporates from the suspension as NH ₃ (g).

The incubation is carried out at 32 ° C. for 3 days without modification of pressure.

At the end of the fermentation, the order of magnitude of the bacterial population is 10 ¹² cells / L.

The fermentation broth thus obtained is then fractionated by centrifugation at 2200 g (acceleration 9.81 m / s ² ) (4000 rpm, Rotofix 32 A Hettich) for a period of about 10 minutes.

The supernatant is recovered and has a dry matter content of 4.58%.

The supernatant is encapsulated with maltodextrin, the amount of maltodextrin being equivalent to twice the solids content of the supernatant.

Drying of the supernatant thus treated is carried out using a drier-atomizer, preferably that marketed by Gea under the name "Gea Mobile Minor®" under the following conditions:

pH: 5.64 (corrected with sodium hydroxide / potassium hydroxide and fixed at 7.0 to improve the fixation of the flavors on maltodextrin),

temperature of the liquid supernatant with maltodextrin: fixed at 4 ° C. for bacteriological and aromatic preservation,

- inlet air temperature: 280 ° C,

- outlet air temperature: 90 ° C,

Brix: l, l%,

- Drying speed: 2 L / h.

Thus, at the end of the supernatant drying step, an emmental flavor is obtained which is in pulverulent form. Example 3

Analysis of the supernatant

The supernatant alone (without maltodextrin) in the preceding Example 2 is analyzed: - in gas phase chromatography coupled to mass spectrometry

(GC / MS),

in Ionic Chromatography Conductrometric Detection (IC / CD).

The purpose of these analyzes is to search for and identify the organic compounds present in the supernatant alone. The presence of volatile organic acids from dairy products is more particularly sought.

1 / Analysis of Volatile Compounds in Chromatography Gas Phase Coupled to Mass Spectrometry (GC / MS)

a / Method

Sample preparation

Weighed 2 ml of sample from the supernatant alone in a 22 ml pillbox.

Crimping the pill box with a Teflon rubber cap.

Heating at 80 ° C for 20 minutes.

Injection of 1 ml in gas chromatography coupled with mass spectrometry.

b / Results

Gas chromatographic analysis showed the presence of some peaks. The identification is done by a computerized database search (NIST).

The results of NIST are given in Table 1 below.

Table 1

The supernatant mainly comprises propionic acid. 2 / Organic Acid Analysis in Ionic Chromatography Detection

Conductrimetric (IC / CD).

a / Method

Sample preparation:

Dilution of the supernatant sample alone in water.

Injection of 1 mΐ in ion chromatography conductimetric detection.

Quantification by external calibration

b / Results

The results are summarized in Table 2 below.

Table 2

3 / Conclusions

The supernatant contains mainly propionic acid and acetic acid at levels of 7160 and 1900 mg / kg, respectively.

Ethanol, 2-butanone, 3-hydroxy (acetoin) and 1,2-propanediol (propylene glycol) have also been identified.

Example 4

Test on a panel of consumers of the emmental flavor of the aroma of the invention

The emmental flavor, which is the powder obtained at the end of Example 2, was tested by a panel of consumers as soon as it was obtained and after 6 months of storage on a maltodextrin support.

This aroma has been mixed with the following food products: water, cream cheese, peanut-based vegetable cheese, fresh cheese and bread, peanut-based vegetable cheese and bread. The so-called "naive" taster panel is made up of 10 lists, including 4 women and 6 men, aged between 19 and 65 years old.

The flavor formulation was made at 0.25% w / w for liquid food products and at 0.75% w / w for fresh cheese, bread and groundnut food products.

The results obtained are summarized in Table 3 below.

Table 3

Conclusion

The results obtained confirm the flavoring aspect of the emmental flavor of the invention, which evokes the emmental flowering flavor typical of propionic acid.

BIBLIOGRAPHIC REFERENCES

(1) Babuchowski, A., Laniewska-Moroz, L., & Warminska-Radyko, I. (1999). Propionibacteria in fermented vegetables. Milk, 79 (1), 113-124;

(2) Dufour, J.P., Melotte, L., & Srebmik, S. (1992). Sorghum malts for the production of a lager beer. J. Am. Soc. Brew. Chem, 50 (3), 110-119;

(3) Filya, I. (2003). The effect of Lactobacillus buchneri and Lactobacillus plantarum on fermentation, aerobic stability, and ruminal degradability of low dry matter com and sorghum silages. Journal of Dairy Science, 86 (11), 3575-3581;

(4) Wang, S., & Copeland, L. (2015). Effect of acid hydrolysis on starch structure and functionality: A review. Critical reviews in food science and nutrition, 55 (8),

1081-1097.

Claims

A process for the preparation of an emmental flavor, characterized in that it comprises the following steps:

- grinding of sorghum seeds (Sorghum bicolor);

sterilization of the aqueous suspension;

2. Preparation process according to claim 1, characterized in that the sorghum is selected from the group comprising red sorghum, white sorghum and mixtures thereof.

3. Preparation process according to claim 1 or claim 2, characterized in that the grinding stage of the sorghum seeds is carried out, preferably dry, until a powder having a particle size of from 0 is obtained. 8 mm at 1, 2 mm.

4. Preparation process according to any one of claims 1 to 3, characterized in that:

5. Preparation process according to any one of claims 1 to 4, characterized in that it comprises, at the end of the step of preparation of the aqueous suspension, and before the sterilization step, a step of deoxygenation of the aqueous suspension, said deoxygenation step preferably being carried out by nitrogenizing said aqueous suspension until the concentration of dissolved oxygen present in the suspension is less than or equal to 5%.

6. Preparation process according to any one of claims 1 to 5, characterized in that the sterilization of the aqueous suspension is carried out at a temperature ranging from 100 ° C to 140 ° C, for a period ranging from 10 to 30 minutes .

Preparation process according to any one of claims 1 to 6, characterized in that the saccharification enzyme added in the sterilized suspension comprises an alpha-amylase and a glucoamylase, preferably in a 1: 1 ratio, said enzyme saccharification is preferably a mixture of two enzymes marketed by Lyven under the name "Amylyve A30" and "Amylyve AG300".

8. Preparation process according to any one of claims 1 to 7, characterized in that the propionic fermentation is carried out at a temperature ranging from 28 ° C to 34 ° C for a period ranging from 68 hours to 76 hours, and preferably for 72 hours.

9. Preparation process according to any one of claims 1 to 8, characterized in that it comprises, at the end of the propionic fermentation step, the following steps:

recovery of the supernatant obtained at the end of the fractionation step of the fermentation must,

drying the supernatant thus recovered,

recovery of Emmental aroma which is in pulverulent form.

10. Preparation process according to claim 9, characterized in that the supernatant recovered at the end of the fractionation step is arranged, before drying, on a flavor carrier selected from the group comprising maltodextrin, the modified starches flour, dextrins, cyclodextrin and mixtures thereof, and is preferably maltodextrin.

11. Preparation process according to claim 10, characterized in that the amount of aroma carrier, and preferably maltodextrin, relative to the supernatant recovered at the end of the fractionation step is twice the percentage of dry matter of said supernatant.

12. Preparation process according to any one of claims 9 to 11, characterized in that the emmental flavor, which is in pulverulent form, comprises:

a quantity of propionic acid ranging from 3% to 4% w / w, preferably from

3.4% to 3.6% w / w,

an amount of acetic acid ranging from 0.4% to 1.3% w / w, preferably from 0.7% to 1.0%, and even more preferably from 0.8% to 0.9% m / m, said percentages being percentages by weight relative to the total mass of the emmental flavor in the form of powder.