SK500652022A3 - Lactic acid bacteria strains Lactococcus lactis 33S7, Lacticaseibacillus paracasei LP ZM-2, use of said strains, method of production of fresh soft cheese and ripening soft cheese from goat's milk, products produced by this method - Google Patents

Abstract

The subject of the invention are the lactic acid bacteria strain Lactococcus lactis 33S7, deposited under the number CCM 9287 in the Czech collection of microorganisms of the Masaryk University in Brno, and the strain Lacticaseibacillus paracasei LP ZM-2, deposited under the number CCM 9286 in the Czech collection of microorganisms of the Masaryk University in Brno. Lactococcus lactis 33S7 is a homofermentative, lactic acid-producing Gram-positive bacterium isolated from sheep's lump cheese made from raw sheep's milk without the addition of dairy cultures. Lacticaseibacillus paracasei LP ZM-2 is a homofermentative, lactic acid-producing gram-positive bacterium isolated from raw goat's milk. The invention also relates to fresh soft cheeses and maturing soft cheeses based on goat's milk produced using the mentioned strains of bacteria and the method of production of these cheeses.

Description

Field techniques

The invention relates to the application of newly characterized and hitherto unused strains of lactic acid bacteria with beneficial properties in the production of fresh soft and ripening soft cheeses based on goat's milk.

Current state of the art

On the Slovak market, goat's milk-based cheeses are still available, in the production of which commercially available starter cultures are used, similar to cheeses made from cow's or sheep's milk. The most commonly available are fresh and ripening cheeses, and from ripening cheeses, hard and moldy cheeses. These products do not declare any functional or prosthetic properties. In addition, the use of starter cultures isolated from a different environment than non-cow milk (goat, sheep) can suppress the typical sensory character of non-cow milk during the fermentation process. Products with a declared beneficial/probiotic effect according to EFSA regulations, that is, containing such probiotic/beneficial strains that have such an effect confirmed by clinical studies, are produced from cow's milk. The combination of the favorable composition and properties of goat's milk with cultures that produce biologically active substances and, moreover, survive in the environment of the gastrointestinal tract, in fresh and ripening cheeses is rare and not yet available on the Slovak market. These mentioned properties not only have an enhanced health effect for the consumer, but also increase the durability of such products without the use of additives.

The essence of the invention

The essence of this invention consists in the application of newly isolated, commercially unused strains of lactic acid bacteria Lacticaseibacillus paracasei LP ZM-2 CCM 9286 and Lactococcus lactis 33S7 CCM 9287 with beneficial properties (biological activity based on bacteriocin-protein substances and survival in the gastrointestinal tract), in the production of fresh soft cheeses and ripening soft cheeses based on goat's milk.

The strain Lacticaseibacillus paracasei LP ZM-2 was isolated from raw goat's milk and the strain Lactococcus lactis 33S7 from sheep's lump cheese, which was made from raw sheep's milk without the addition of dairy cultures.

The strain Lactococcus lactis 33S7 is stored under the number CCM 9287 in the Czech collection of microorganisms of the Masaryk University in Brno.

Lactococcus lactis 33S7 is a homofermentative, lactic acid-producing Gram-positive bacterium. It belongs to the phylum/tribe Firmicutes, class Bacilli, order Lactobacillales, family Streptococcaceae, genus Lactococcus. The strain was isolated from sheep's lump cheese made from raw sheep's milk and was taxonomically classified based on its protein spectrum using the MALDI-TOF identification system. From the point of view of safety, it is important that it does not cause hemolysis ( _v -hemolysis). It survives in an environment simulating the digestive tract (bile and low pH).

The strain is characterized by suitable technological properties - it grows well on milk, where it creates a sensory-appealing coagulum. It is also characterized by optimal leavening activity, which is why it is suitable as a starter strain in cultures. It is able to grow in co-cultures with other strains of lactic acid bacteria. It grows at temperatures between 20 and 37 °C, optimally at temperatures between 30 °C and 37 °C. It is tolerant to lower concentrations of NaCl (up to 5%), so it can also be used in the production of cheeses with the addition of salt.

The strain Lacticaseibacillus paracasei LP ZM-2 is stored under the number CCM 9286 in the Czech collection of microorganisms of the Masaryk University in Brno.

Lacticaseibacillus paracasei LP ZM-2 is a homofermentative, lactic acid-producing Gram-positive bacterium. It belongs to the phylum/tribe Firmicutes, class Bacilli, Order Lactobacillales, Family Lactobacillacae and Genus Lacticaseibacillus. The strain was isolated from raw goat's milk and was taxonomically classified using the MALDI-TOF identification system. From the point of view of safety, it is important that it does not form hemolysis (v-hemolysis). Sufficiently survives in an environment simulating the digestive tract (bile and low pH). It is able to form a biofilm, which is a beneficial feature in the case of a probiotic strain. It is capable of producing an unspecified biologically active substance. It also produces useful lactase - the β-galactosidase enzyme.

The strain is characterized by suitable technological properties - it grows well on milk, where it creates a sensory-appealing coagulum. It is also characterized by optimal leavening activity and is therefore suitable as

SK 50065-2022 A3 starter strain in cultures. It is able to grow in co-cultures with other strains of lactic acid bacteria. It grows at temperatures between 20 and 37 °C, optimally at temperatures between 30 °C and 37 °C. It is tolerant to lower concentrations of NaCl (up to 5%), so it can also be used in the production of cheeses with added salt.

Another aspect of the invention is an inoculum/ferment for the production of fresh soft and ripening soft cheeses containing the strains of lactic acid bacteria Lactococcus lactis 33S7 CCM 9287 and Lacticaseibacillus paracasei LP ZM-2 CCM 9286.

Another aspect of this invention is the use of the disclosed new strains of lactic acid bacteria as an inoculum/fermenter for the production of fresh soft cheeses and matured soft cheeses from goat's milk.

The third aspect of this invention is the method of production of fresh soft cheeses and ripening soft cheeses from goat's milk, the essence of which is that an inoculation inoculum/ferment, consisting of a mixture of the subject strains of lactic acid bacteria in the amount of 1 to 2 vol., is added to the goat's milk. % with respect to the volume of goat's milk, Lactococcus lactis 33S7 and Lacticaseibacillus paracasei LP ZM-2 in an application ratio of 6:4.

Curing of milk, slicing, hardening and shaping of the curd takes place at temperatures of 30 to 37 °C, optimally at a temperature of 33 °C, with subsequent fermentation of the cheese at temperatures of 20 to 25 °C, optimally at a temperature of 23 °C, for a period of 20 to 24 hours , until reaching the optimal active acidity (pH) of the cheese of 5.0 to 5.2. After fermentation, the cheeses were salted in a salt solution with a NaCl concentration of 18 to 20%. The ripening soft cheese, after salting, then ripens at a temperature of 12 to 15 °C for 3 to 7 days. Fresh soft cheese (after drying) and maturing soft cheese (after ripening) are packed in consumer packaging and kept at a temperature of up to 8 °C until shipment.

For the production of fresh soft and matured soft cheeses, raw goat's milk can be used with the original fat content or the fat content can be standardized to the desired fat content. Goat milk with the required fat content can be homogenized at a temperature of 55 to 60 °C and a pressure of 17 to 20 MPa.

Raw goat's milk can be heat-treated before processing - pasteurized at a temperature of 72 to 75 °C for 15 to 20 seconds or at a temperature of 63 to 65 °C for 20 to 30 minutes.

Strains for the preparation of inoculum/ferment are cultured on pasteurized goat's milk (at a pasteurization temperature of 85 °C, 1 to 5 minutes) at a temperature of 30 °C, 24 hours, Lactococcus lactis 33S7 and at a temperature of 37 °C, 48 hours Lacticaseibacillus paracasei LP ZM-2.

According to a preferred embodiment, the pasteurized goat's milk is cooled to a temperature of 33 °C, at which time the milk is fermented and the curd is processed, an inoculating inoculum/ferment is added, consisting of selected strains of the lactic acid bacteria Lactococcus lactis 33S7 and Lacticaseibacillus paracasei LP ZM-2 in a strain ratio of 6 : 4. The amount of added inoculation inoculum/ferment in total is 1 to 2 vol. % with respect to the volume of processed goat's milk.

The production of fresh soft and ripening soft cheeses (milk curdling, slicing, hardening and forming of the curd) takes place at a temperature of 33 °C.

The cheeses are then fermented at a temperature of 23 °C for 20 to 24 hours, until the cheese's pH is 5.0 to 5.2. After fermentation, the cheeses were salted in a salt solution with a NaCl concentration of 18 to 20%. After rising and salting, the maturing soft cheese then ripens at a temperature of 12 to 15 °C for 3 to 7 days. Fresh soft cheese (after drying) and maturing soft cheese (after ripening) are packed in consumer packaging and kept at a temperature of up to 8 °C until shipment.

The mentioned strains of lactic acid bacteria Lactococcus lactis 33S7 and Lacticaseibacillus paracasei LP ZM-2 have suitable technological and beneficial (probiotic) properties; they are bioactive (substances-metabolites produced by them can inhibit unwanted bacteria), tolerate and survive in the gastrointestinal tract and do not produce harmful enzymes or biogenic amines. The strains are suitable for use in the dairy industry in the production of cheese, as their bioactivity can guarantee an extension of the product's shelf life, while maintaining health-promoting properties.

In the combination of these strains of lactic acid bacteria with goat's milk in the production of fresh soft and ripened soft cheeses, due to the properties of goat's milk (unlike cow's milk, it is characterized by a reduced allergenic potential, better digestibility), cheeses suitable for a wide population of residents, especially intolerant of cow's milk, are obtained milk, with digestive difficulties, etc.

SK 50065-2022 A3

Examples of implementation of the invention

Example 1

Preparation of inoculum/ferment for the production of fresh soft and ripening soft cheeses The strain Lactococcus lactis 33S7 CCM 9287 for the preparation of sourdough was cultivated on pasteurized goat's milk (pasteurization temperature 85 °C, 1 to 5 minutes), at a temperature of 30 °C, 24 h. in the amount of 1 vol. % per volume of milk.

Lacticaseibacillusparacasei strain LP ZM-2 CCM 9286 for the preparation of sourdough was cultivated on pasteurized goat's milk (pasteurization temperature 85 °C, 1 to 5 minutes) at a temperature of 37 °C, 48 hours. in the amount of 1 vol. % per volume of milk.

Example 2

Application of strains of lactic acid bacteria Lactococcus lactis 33S7 CCM 9287 and Lacticaseibacillus paracasei LP ZM-2 CCM 9286 in the production of fresh soft and ripening soft cheeses based on goat's milk.

Raw goat's milk with its original fat content is heat-treated at a temperature of 72 °C for 20 seconds and then cooled to a temperature of 33 °C.

Inoculation inoculum/ferment consisting of selected strains of Lactococcus lactis 33S7 and Lacticaseibacillus paracasei LP ZM-2 is added to pasteurized and cooled goat's milk at 33 °C in a weight ratio of 6:4. The amount of added inoculum/ferment is 1 volume . % with respect to the volume of processed goat's milk.

After mixing the yeast in the pasteurized goat's milk, an addition of 36% calcium chloride solution in the amount of 2 ml/10 liters of goat's milk and an addition of Fromase 220 TL rennet solution in an amount of 2 ml/10 liters of milk are added to the mixture. The milk is fermented at a temperature of 33 °C for 30 minutes.

After curdling the milk, the cheese is cut into cubes of 4 to 5 cm in size, followed by rest for 5 minutes at a temperature of 33 °C. This is followed by hardening of the curd with release of the whey (crushing - harping, mixing the cheese grain for 20 minutes, at a temperature of 33 °C.

After solidification, the cheese is formed - filled into molds or cheese cloths, in which the cheeses are turned (after 1 hour, then after 3 hours, then in the morning) to ensure that the whey drips off. The cheeses are then fermented at a temperature of 23 °C for 20 hours, until a pH value of 5.0 is reached.

After fermentation, the cheeses were salted in a salt solution with a NaCl concentration of 18%. The salting time depends on the size of the cheese (with a cheese size of 0.1 kg, the salting time is 20 minutes). The maturing soft cheese, after rising and salting, then matures at a temperature of 12 °C for 3 days.

Fresh soft cheese (after drying) and maturing soft cheese (after ripening) are packed in consumer packaging and kept at a temperature of up to 8 °C until shipment.

Finished cheeses are checked for correct labeling, fat content, solids, salts, active acidity, microbiological requirements, sensory evaluation is carried out (required: appearance and color - milky white to creamy; consistency - soft, fragile, depending on the fat content; taste and aroma - slightly sour milky, slightly salty). The mentioned product met the quality requirements.

Example 3

Application of strains of lactic acid bacteria Lactococcus lactis 33S7 CCM 9287 and Lacticaseibacillus paracasei LP ZM-2 CCM 9286 in the production of fresh soft and ripening soft cheeses based on goat's milk.

Raw goat's milk with its original fat content is heat-treated at a temperature of 72 °C for 20 seconds and then cooled to a temperature of 33 °C.

Inoculation inoculum/ferment consisting of selected strains of Lactococcus lactis 33S7 and Lacticaseibacillus paracasei LP ZM-2 is added to pasteurized and cooled goat's milk at 33 °C in a weight ratio of 6:4. The amount of added inoculum/ferment is 2 volumes . % with respect to the volume of processed goat's milk.

After mixing the yeast in the pasteurized goat's milk, an addition of 36% calcium chloride solution in the amount of 4 ml/10 liters of goat's milk and an addition of Fromase 220 TL rennet solution in an amount of 4 ml/10 liters of milk are added to the mixture. Milk curdling takes place at a temperature of 33 °C for 35 minutes.

After curdling the milk, the cheese is cut into cubes of 4 to 5 cm in size, followed by rest for 5 minutes at a temperature of 33 °C. This is followed by hardening of the curd with release of the whey (crumbling - harping, mixing the cheese grain for 25 minutes, at a temperature of 33 °C.

Once desired, the cheese is formed - filled into molds or cheese cloths, in which the cheeses are rotated (after 1 hour, then after 3 hours, then in the morning) to ensure that the whey drips off. The cheeses are then fermented at a temperature of 23 °C for 24 hours, until a pH value of 5.2 is reached.

SK 50065-2022 A3

After fermentation, the cheeses were salted in a salt solution with a NaCl concentration of 20%. The salting time depends on the size of the cheese (with a cheese size of 0.3 kg, the salting time is 30 minutes). After rising and salting, the maturing soft cheese is then matured at a temperature of 15 °C for 7 days.

Fresh soft cheese (after drying) and maturing soft cheese (after ripening) are packed in consumer packaging 5 and kept at a temperature of up to 8 °C until shipment.

Finished cheeses are checked for correct labeling, fat content, solids, salts, active acidity, microbiological requirements, sensory evaluation is carried out (required: appearance and color - milky white to creamy; consistency - soft, fragile, depending on the fat content; taste and aroma - slightly sour milky, slightly salty). The mentioned product met the quality requirements.

Claims (7)

1. Lactococcus lactis 33S7, stored under the number CCM 9287 in the Czech collection of microorganisms of the Masaryk University in Brno, is a homofermentative, lactic acid-producing Gram-positive bacterium isolated from sheep lump cheese made from raw sheep's milk. 2. Lacticaseibacillus paracasei LP ZM-2, stored under the number CCM 9286 in the Czech collection of microorganisms of the Masaryk University in Brno, is a homofermentative, lactic acid-producing Gram-positive bacterium isolated from raw goat's milk. 3. Inoculum/ferment for the production of fresh soft and ripening soft cheeses containing strains of lactic acid bacteria Lactococcus lactis 33S7 CCM 9287 and Lacticaseibacillus paracasei LP ZM-2 CCM 9286 according to claim 1 and 2. 4. A method for the production of fresh soft and ripening soft cheeses based on goat's milk, characterized in that it contains the following steps: adding to the goat's milk an inoculation inoculum/ferment consisting of a mixture of strains of lactic acid bacteria according to claim 1 and 2 in an amount of 1 to 2 vol. % with respect to the volume of goat's milk, Lactococcus lactis 33S7 CCM 9287 and Lacticaseibacillus paracasei LP ZM-2 CCM 9286 in an application ratio of strains of 6:4; production of fresh soft and ripening soft cheeses, curdling of milk, slicing, hardening and shaping of curds, at a temperature of 33 °C; subsequent acidification of the cheeses at a temperature of 23 °C, for 20 to 24 hours, until the pH of the cheese is 5.0 to 5.2; after reaching the desired pH value, salting the cheeses in a salt solution with a NaCl concentration of 18 to 20% for 20 to 30 minutes; subsequent maturation of ripening soft cheese after salting at a temperature of 12 to 15 °C, for 3 to 7 days; packaging of fresh soft cheese (after drying) and maturing soft cheese (after ripening) in consumer packaging and storage until shipment at a temperature of up to 8 °C. 5. The method according to claim 3, characterized in that the goat's milk is pasteurized. 6. Use of original strains of lactic acid bacteria Lactococcus lactis 33S7 CCM 9287 and Lacticaseibacillus paracasei LP ZM-2 CCM 9286 in the production of fresh soft cheeses and ripening soft cheeses. 7. Fresh soft cheeses and maturing soft cheeses based on goat's milk prepared by adding strains of lactic acid bacteria according to claim 1 and 2, in a total amount of 1 to 2 vol. % with respect to the volume of goat's milk, Lactococcus lactis 33S7 CCM 9287a Lacticaseibacillus paracasei LP ZM-2 CCM 9286 in the application ratio of strains 6 : 4, and at a temperature of 33 °C the ongoing process of milk curd and curd processing, at a temperature of 23 °C, 20 to For 24 hours, the cheeses are left to ferment, the fermentation is finished when the pH of the cheese reaches a value of 5.0 to 5.2; after reaching the required pH value, the cheeses are salted in a salt solution with a NaCl concentration of 18 to 20%, for 20 to 30 minutes; the maturing soft cheese, after salting, then ripens at a temperature of 12 to 15 °C for 3 to 7 days.