ITMO20090067A1 - COMPOSITION BASED ON MICRORGANISMS USED TO PREPARE A FOOD PRODUCT - Google Patents

Description

Composition based on microorganisms that can be used to prepare a food product The invention concerns a composition based on microorganisms that can be used to prepare a food product, in particular a milk-based probiotic food product.

Among the milk-based food products, a type of fermented milk called “kefir” (word deriving from the Turkish “kef” or “keif” which would mean “pleasant taste” or also “well-being”) and originating in the North Caucasus is known. Kefir is an aromatic sour milk, slightly alcoholic, as it contains ethanol in a concentration of 0.1-0.3% v / v, and has a sparkling taste (thanks to the CO2 produced during fermentation). Kefir has a smoother consistency than yogurt and is therefore considered a drink.

Kefir is rich in B vitamins (vitamin B12, folic acid or vitamin B9), mineral nutrients (calcium, phosphorus) and essential amino acids (for example, tryptophan), and as such is counted in medicine among the so-called "functional foods probiotics ”, ie foods integrated with live microorganisms having a beneficial effect on health. In particular, the intake of kefir allows to normalize the function of the digestive system, preventing, and sometimes treating, digestive disorders, gastritis, intestinal diseases and diarrhea in adults and children.

The traditional method of producing kefir requires the addition of so-called "kefir granules", containing a mixed microflora, to cow's or goat's milk. In the latter, the kefir granules therefore act as a "starter", that is, as activators of fermentation.

Kefir grains are small yellowish-white masses with a diameter between 1-6 mm and 1-2 cm and a twisted and wrinkled surface. The kefir granules are substantially composed of an elastic matrix of microbial origin, the kefirano polysaccharide, which incorporates a considerable variety of microorganisms in symbiotic association, and therefore stable.

The microflora present in kefir granules includes:

- Lactic ferments (also indicated by the acronym LAB = Lactic Acid Bacteria), such as lactococci, lactobacilli, Leuconostoc spp .;

- Alcoholic ferments, such as yeasts belonging to the genera Saccharomyces, Kluyveromyces;

-Acetic ferments, such as those belonging to the genus Acetobacter.

The kefir granules, once recovered from the kefir, can be immediately reused to produce new kefir, or stored. The kefir granules can be stored in the refrigerator (at a temperature between 1 ° C and 4 ° C) for a few days, or they can be frozen and stored like that for a few months. The kefir granules can be "cultivated" (that is, they can be placed in conditions suitable for the growth of the microflora contained therein) continuously, so as to increase in number and volume, with a minimum increase of 5-10% on occasion of each new kefir production.

It should be noted that, if stored in unsuitable hygienic conditions, kefir granules can be polluted by the so-called "wild yeasts" (natural yeasts), which generate unpleasant odors, and by coliform bacteria, putrefactive microorganisms that produce toxic as well as malodorous substances.

Consequently, it is necessary to periodically wash the kefir granules with cold water, in particular after each new kefir production, to eliminate any surface polluting microflora. However, this procedure is not free from drawbacks: in fact, together with the polluting microflora, part of the useful microflora is also removed from the granules, ie the lactic ferments which are mainly arranged on the surface of the granule.

Since the traditional method is somewhat laborious and substantially inconvenient, especially if you want to produce large quantities of kefir, instead of adding kefir granules to the milk, the latter is inoculated with a so-called "starter culture". The starter culture can be constituted by kefir deprived of the granules, or by the various enzymes (lactic, alcoholic, acetic) belonging to the microbial flora of kefir, in freeze-dried form. If freeze-dried enzymes are used, a drink is obtained that is not identical to traditional kefir (obtained by means of granules), but which is still very similar to the latter from the point of view of organoleptic and nutritional properties.

In this way it is possible to obtain in a substantially easy way sufficient quantities of kefir for preparing probiotic food products containing kefir, for example kefir ice creams, having beneficial properties for the health of consumers.

However, although kefir is widely distributed and appreciated in various countries and the corresponding health benefits are known, it can still be difficult for the consumer public to like and accept ice cream products which, as they contain kefir, are equipped with a aroma and palatability significantly different from those of similar products obtained through unfermented milk.

In fact, the known recipes for the preparation of kefir-based ice creams require the presence of sucrose in concentrations on average higher than 20% in order to provide the product with a satisfactory palatability. However, the abundant use of sucrose is not an optimal solution for many consumers, as it is not very compatible with the dietary needs of the latter.

There is therefore a need for food products, such as ice cream, in which the probiotic properties of kefir are associated with aromatic and palatability properties designed to satisfy the tastes of consumers.

One purpose of the invention is to improve probiotic food products.

Another purpose is to improve kefir-based probiotic food products.

A further object is to make available a food product capable of combining the probiotic properties of kefir with satisfactory aromatic and palatability properties.

According to the invention, a composition is provided for preparing a kefir-like fermented product, as defined in claim 1.

Thanks to the invention, a composition based on microorganisms is made available which can be used to prepare a fermented product which is similar to kefir, has the same probiotic properties as the latter and nevertheless has a pleasantly aromatic taste (similar to the taste of butter ).

The fermented "kefir-like" product thus obtained can in turn be used, as an ingredient, to prepare a food product.

For example, it is possible to inoculate a cow's milk with the composition according to the invention so as to obtain a kefir-like fermented milk, and this kefirsimil fermented milk can in turn be used as an ingredient to prepare a probiotic ice cream product. The latter, unlike the known kefir ice creams, is provided with a better palatability and a more pleasant taste, thus being more appreciated by the consumer public.

Thanks to the pleasant taste of the kefirsimil fermented product obtainable through the composition according to the invention, it is possible to prepare kefir-based ice cream products using lower amounts of sucrose than known recipes, so as to respect the dietary needs of consumers.

The composition according to the invention includes a mixture of lactic ferments and is free of alcoholic ferments and acetic ferments which are part of the typical microflora of kefir granules.

The lactic ferments of the mixture have probiotic, aromatic and acidifying activity, and have been selected and associated in such a way as to give a pleasantly aromatic taste to the kefir-like fermented product. In particular, the absence of alcoholic ferments and acetic ferments in the mixture contributes to giving a less "pungent", and therefore more pleasant, taste to the kefir-like fermented product obtained through the composition according to the invention.

The mixture of lactic ferments includes the bacterial species listed in the following table 1:

Table 1

Lactobacillus acidophilus

Lactobacillus casei ssp. casei

Lactobacillus delbrueckii ssp. bulgaricus

Streptococcus thermophilus

Lactococcus lactis ssp. lactis

Lactococcus lactis ssp. cremoris

Lactococcus lactis ssp. lactis biovar diacetylactis Leuconostoc mesenteroides ssp. cremoris

Among the species listed in Table 1, those belonging to the genus Lactococcus and the genus Leuconostoc are mesophilic species.

The main properties of the lactic ferments present in the composition according to the invention are summarized below in Table 2 and Table 3. Table 2 shows the optimal pH values (range) and the minimum, optimal growth temperatures (° C) (range) and maximum, while table 3 shows biochemical and metabolic properties (production of lactic acid, carbon dioxide and aromas; probiotic activity):

Table 2

Table 3

The following table 4 lists bacterial strains (isolated at the Centro Sperimentale del Latte S.p.A.), selected from the species listed in table 1 and used to prepare the mixture of lactic ferments included in the composition according to the invention.

The strains are listed together with the corresponding numbers and filing dates in the BCCM <TM> / LMG collection of the University of Gent (K.L Ledeganckstraaat 35, B-9000 Gent, Belgium):

Table 4

In one version of the composition, the lactic ferments of the mixture are in lyophilized form.

In another version, the composition includes an excipient (for example, food grade lactose) and has a percentage formula shown in the following table 5:

Table 5

The mixture of lactic ferments mentioned in table 5 includes the bacterial species listed in table 1.

In one version of the composition, the lactic ferment mixture comprises one or more of the strains listed in Table 4.

The qualitative and quantitative formula of the mixture of lactic ferments of table 5 is shown in the following table 6.

In table 6 (and in the following tables 7, 8, 9, 11 and 13) the Lactococcus lactis ssp. lactis, Lactococcus lactis ssp. cremoris, Lactococcus lactis ssp. lactis biovar diacetylactis, Leuconostoc mesenteroides ssp. cremoris are collectively indicated with the term "mesophilic component":

Table 6

In one version, the mixture of lactic ferments has a qualitative and quantitative formula shown in the following table 7:

Table 7

In another version, the mixture of lactic ferments has a qualitative and quantitative formula shown in the following table 8:

Table 8

In a further version, the mixture of lactic ferments has a qualitative and quantitative formula shown in the following table 9:

Table 9

The quantitative formulas of the mixture of lactic ferments shown in Tables 7, 8 and 9 are only an example of the possible quantitative formulas. In fact, the mixture of lactic ferments can be suitably varied, from a quantitative point of view, without this significantly altering the probiotic, aromatic and acidifying activity of the mixture.

In a further version, the composition has a percentage formula shown in the following table 10:

Table 10

In the composition according to table 10, the mixture of lactic ferments has a qualitative and quantitative formula shown in the following table 11:

Table 11

In the mixture of lactic ferments according to table 11, the mesophilic component has a qualitative and quantitative formula shown in the following table 12:

Table 12

The following table 13 shows the concentration in UFC / g of the bacterial species included in the mixture of lactic ferments referred to in the previous tables 10, 11 and 12:

Table 13

The composition according to the invention can be used as an ingredient to produce a kefirsimil fermented product, having an aromatic and particularly pleasant taste.

For example, a composition according to Tables 10, 11, 12 and 13, possibly including one or more of the bacterial strains listed in Table 4, can be freeze-dried and used as a starter with which to produce a kefir-like fermented milk.

The lyophilized starter can be packaged in single-dose containers, such as sachets.

In one version, each sachet contains a dose equal to 5 grams of composition, in which the mixture of lactic ferments is equal to 0.5 grams and the excipient is equal to 4.5 grams.

To produce a fermented milk using the aforementioned starter, a dose of composition (i.e. the contents of a sachet) is poured into a container containing a predetermined volume of milk, cream or a mixture of milk and cream, at a temperature between between 22 ° C and 30 ° C.

After mixing the starter with the milk (or cream, or milk / cream mixture), the container is closed and the milk / starter mixture (or cream / starter, or milk / cream / starter) is incubated at a temperature of 22 ° -30 ° C for 12-24 h, until reaching a predetermined pH and a desired aroma.

The fermented product thus obtained is a kefir-like fermented milk (or fermented cream), which can be used cold (i.e., without being pasteurized) as an ingredient to prepare probiotic ice cream products, such as ice cream, ice lollies and semifreddo.

Some probiotic ice cream products are exemplified below, to prepare which a kefir-like fermented product obtained through the composition according to the invention is used as an ingredient.

Example 1

A probiotic kefir ice cream (in a quantity equal to 1 kg) is obtained starting from the ingredients listed in the following table 14:

Table 14

The ingredient indicated as "neutral component" may include, for example, a stabilizing agent and an emulsifying agent.

The stabilizing agent may include locust bean gum.

The emulsifying agent may include sucresters (sucrose esters of fatty acids).

The kefir-like fermented product is made by mixing a freeze-dried starter with UHT cow's milk. The starter consists of the composition according to tables 10, 11, 12 and 13 (possibly including one or more of the bacterial strains listed in table 4), in lyophilized form.

After adding the starter, the milk is incubated at a temperature of 22-30 ° C for a time sufficient to reach a pH between 4.5 and 4.2.

The other components (sucrose, dextrose, whole milk powder, neutral component) are mixed together (separately from the kefir-like fermented product) and pasteurized.

The pasteurized mixture thus obtained is cooled and mixed in turn with the kefirsimile fermented product, so as to obtain a probiotic kefir ice cream.

The solid substance content of probiotic kefir ice cream is shown in the following table 15:

Table 15

In table 15 (and in subsequent tables 16, 18, 19, 21 and 22) the meaning of the abbreviation SML is “Solidi Magri del Latte”.

The probiotic kefir ice cream prepared using the ingredients in table 14 has the balancing characteristics indicated in the following table 16:

Table 16

The term "balancing characteristics" of an ice cream defines the percentage contents of the various solid ingredients, which are chosen in such a way as to mutually balance the solid and liquid substances present in the ice cream, so as to obtain a product with suitable organoleptic and conservation.

Example 2

A probiotic kefir ice cream (in a quantity equal to 1 kg) is obtained starting from the ingredients listed in the following table 17:

Table 17

The ingredient indicated as "neutral component" is similar to the neutral component described in Example 1.

The preparation procedure of the kefirsimil fermented product and the probiotic kefir ice cream is the same as the preparation procedure described in Example 1.

The solid substance content of probiotic kefir ice cream is shown in the following table 18:

Table 18

The probiotic kefir ice cream prepared using the ingredients in table 17 has the balancing characteristics indicated in the following table 19:

Table 19

Example 3

A probiotic kefir ice cream (in a quantity equal to 1 kg) is obtained starting from the ingredients listed in the following table 20:

Table 20

The ingredient indicated as "neutral component" is similar to the neutral component described in Example 1.

The preparation procedure of the kefirsimil fermented product and the probiotic kefir ice cream is the same as the preparation procedure described in Example 1.

The qualitative and quantitative percentage formula of the solid substances present in probiotic kefir ice cream is shown in the following table 21:

Table 21

The probiotic kefir ice cream prepared using the ingredients in table 20 has the balancing characteristics indicated in the following table 22:

Table 22

Claims (15)

CLAIMS 1. Composition for preparing a kefir-like fermented product, comprising a mixture of microorganisms consisting of lactic ferments. 2. Composition according to claim 1, wherein said lactic ferments are selected from a group comprising: Lactobacillus acidophilus, Lactobacillus casei ssp. casei, Lactobacillus delbrueckii ssp. bulgaricus, Streptococcus thermophilus, Lactococcus lactis ssp. lactis, Lactococcus lactis ssp. cremoris, Lactococcus lactis ssp. lactis biovar diacetylactis, Leuconostoc mesenteroides ssp. cremoris. 3. Composition according to claim 2, having a percentage formula comprising: Lactobacillus acidophilus 1-10% Lactobacillus casei ssp. casei 4-7% Lactobacillus delbrueckii ssp. bulgaricus 5-30% Streptococcus thermophilus 30-60% mesophilic component 25-40%, said mesophilic component including Lactococcus lactis ssp. lactis, Lactococcus lactis ssp. cremoris, Lactococcus lactis ssp. lactis biovar diacetylactis, Leuconostoc mesenteroides ssp. cremoris. 4. Composition according to claim 3, having a percentage formula comprising: Lactobacillus acidophilus 5% Lactobacillus casei ssp. casei 5% Lactobacillus delbrueckii ssp. bulgaricus 30% Streptococcus thermophilus 30% mesophilic component 30%. 5. Composition according to claim 4, wherein said mesophilic component has a percentage formula comprising: Lactococcus lactis ssp. lactis 60% Lactococcus lactis ssp. cremoris 20% Lactococcus lactis ssp. lactis 10% biovar diacetylactis Leuconostoc mesenteroides ssp. cremoris 10%. 6. Composition according to claim 4, or claim 5, wherein said lactic ferments have the following concentrations in UFC / g: Lactobacillus acidophilus 50 x 10 <9> Lactobacillus casei ssp. casei 50 x 10 <9> Lactobacillus delbrueckii ssp. bulgaricus 10 x 10 <9> Streptococcus thermophilus 200 x 10 <9> mesophilic component 200 x 10 <9>. 7. Composition according to one of the preceding claims, comprising an excipient. 8. Composition according to claim 7, in which said excipient is provided in a percentage by weight of between 95% and 80% and said lactic ferments are provided in a percentage by weight of between 5% and 20%. 9. Composition according to claim 8, when claim 7 depends on one of claims 4 to 6, wherein said excipient is provided in a percentage by weight equal to 90% and said lactic ferments are provided in a percentage by weight equal to 10%. Composition according to one of the preceding claims, wherein said lactic ferments comprise at least one strain deposited in the BCCM <TM> / LMG collection and selected from a group comprising: Lactobacillus acidophilus LMG P – 21904, Lactobacillus acidophilus LMG P – 17503, Lactobacillus casei ssp. casei LMG P – 17504, Lactobacillus delbrueckii ssp. bulgaricus LMG P– 21905, Streptococcus thermophilus LMG P – 21908, Streptococcus thermophilus LMG P – 24652, Streptococcus thermophilus LMG P – 24653, Lactococcus lactis ssp. lactis LMG P – 24651, Lactococcus lactis ssp. cremoris LMG P – 24643, Lactococcus lactis ssp. cremoris LMG P – 24644, Lactococcus lactis ssp. cremoris LMG P – 24645, Lactococcus lactis ssp. lactis biovar diacetylactis LMG P – 24648, Lactococcus lactis ssp. lactis biovar diacetylactis LMG P – 24649, Lactococcus lactis ssp. lactis biovar diacetylactis LMG P – 24650, Leuconostoc mesenteroides ssp. cremoris LMG P - 24646, Leuconostoc mesenteroides ssp. cremoris LMG P - 24647. 11. Fermentation starter comprising a composition according to one of the preceding claims. Food product ingredient, comprising a composition according to one of claims 1 to 10. A food product comprising a composition according to one of claims 1 to 10. Use of a composition according to one of claims 1 to 10 to produce a fermentation starter. Use of a composition according to one of claims 1 to 10 to produce a food product ingredient and / or a food product.