A beef jerky-type natural cheese and its preparation method

Abstract

The present invention provides a beef jerky-type natural cheese and a preparation method thereof. The preparation method provided by the present invention comprises the following processes: a) raw material standardization; b) sterilization, fermentation, and curdling; c) breaking the curd and draining the whey; d) stacking and pressing into shape; e) scalding treatment and cooling. By adopting the above process and controlling some operation steps and conditions, specifically, introducing membrane-filtered casein into the raw materials for standardization treatment, controlling the size of the broken curd cutting blocks, the conditions of pressing into shape, and the conditions of scalding treatment, through multi-faceted cooperation, the prepared natural cheese not only has a high protein content and high nutritional value, but also endows the cheese with the meaty texture of beef jerky, and the shelf life is significantly extended.

Description

Technical Field

[0001] The present invention relates to the field of cheese, and particularly to a beef jerky-type natural cheese and a preparation method thereof. Background Art

[0002] As is well known, cheese is a product obtained by fermenting cow milk. Approximately ten kilograms of cow milk can produce one kilogram of cheese, commonly known as "liquid gold". Therefore, the nutrient content of cheese is much higher than that of cow milk.

[0003] Cheese products are similar to solid foods. In Inner Mongolia, people call cheese "milk tofu". Cheese includes natural cheese and processed cheese. Processed cheese is a product made by melting one or more natural cheeses after crushing and adding emulsifiers and stabilizers.

[0004] Cheese is rich in protein and calcium, convenient to eat, and diverse in variety. Western countries consume more cheese products. In recent years, the domestic demand for cheese products has also been increasing continuously. Pizza, cheese bread, cheese hot pot, etc. are favored by consumers. In addition, when some tourists need to supplement energy during the journey, they often choose beef jerky, but there is no better food to replace beef jerky. Therefore, preparing high-quality beef jerky-type natural cheese has market prospects.

[0005] Therefore, the beef jerky-type natural cheese contains a high content of protein, has high nutritional value, and a relatively long shelf life. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a beef jerky-type natural cheese and a preparation method thereof. The beef jerky-type natural cheese prepared by the present invention not only has a high content of protein and high nutritional value, but also endows the cheese with the texture of beef jerky, and the shelf life is significantly extended.

[0007] The present invention provides a preparation method of a beef jerky-type natural cheese, comprising the following steps:

[0008] a) Standardization of raw materials:

[0009] Mix raw cow milk and membrane-filtered casein and heat them to obtain standardized raw materials;

[0010] b) Sterilization, fermentation, and coagulation:

[0011] After sterilizing the standardized raw materials, add a starter culture for fermentation, and then add rennet for coagulation to obtain a coagulum;

[0012] c) Demulsification and whey drainage:

[0013] Cut and demulsify the coagulum, stir and heat it up. When the pH of the whey reaches 5.2 - 5.6, drain the whey to obtain curd granules;

[0014] d) Stacking and pressing for forming:

[0015] Place the curd particles in a forming mold for pressing and forming to obtain a formed cheese block;

[0016] The pressure for the pressing and forming is 0.6 - 0.8 MPa, and the time is 24 - 48 h;

[0017] e) Blanching treatment and cooling:

[0018] Place the formed cheese block in a liquid medium for blanching and soaking, and then cool it to obtain a beef jerky - type natural cheese;

[0019] The temperature for the blanching and soaking is 85 - 95 °C, and the time is 3 - 5 h.

[0020] Preferably, in the step a), the addition amount of the membrane - filtered casein is 2 wt% - 4 wt% of the raw milk;

[0021] The membrane - filtered casein is Leprino USA.

[0022] Preferably, in the step c), the cutting and demulsification is to cut the coagulum into milk blocks with a length, width, and height of 0.3 - 0.5 cm;

[0023] The temperature increase is to increase to 48 - 55 °C.

[0024] Preferably, in the step a), the heating temperature is 50 - 60 °C;

[0025] Stirring is accompanied during the heating process;

[0026] The rotation speed of the stirring is 800 - 1100 rpm, and the time is 40 min.

[0027] Preferably, in the step e), the liquid medium is water, whey, or reconstituted whey liquid.

[0028] Preferably, in the step b), the sterilization conditions are: holding at 65 °C for 30 min, or holding at 72 °C for 15 s;

[0029] After the sterilization, cooling is also carried out;

[0030] The cooling is to cool to 28 - 32 °C.

[0031] Preferably, in the step b), the fermentation operation is: first add the starter and stir evenly, and then let it stand for fermentation;

[0032] The temperature for the standing fermentation is 28 - 32 °C, and the time is 2 h;

[0033] The starter culture includes one or more of Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. diacetylactis, and Streptococcus thermophilus.

[0034] Preferably, in step b), the time for curdling is 40 min.

[0035] The rennet includes one or more of microbial rennet and animal rennet.

[0036] Preferably, in step e), the cooling is to room temperature or 4°C.

[0037] After the cooling, it further includes: cutting the cooled product into the shape of beef jerky with a sterile knife, and then performing sterile vacuum packaging to obtain beef jerky-type natural cheese.

[0038] The present invention also provides a beef jerky-type natural cheese prepared by the preparation method described in the above technical solution.

[0039] The preparation method of the beef jerky-type natural cheese provided by the present invention first introduces membrane-filtered casein into the raw materials for standardization treatment, and then performs sterilization, fermentation, curdling, demulsification and whey drainage, stacking and pressing for shaping, hot blanching treatment and cooling. Among them, introducing membrane-filtered casein into the raw materials, controlling the size of the demulsified cut blocks, controlling the conditions of pressing and shaping, and the conditions of hot blanching treatment are crucial. By adding membrane-filtered casein, the content of active casein is increased, and under the action of rennet in the subsequent steps, this protein can be further hydrolyzed, so that the final cheese product has a high protein content and solid content, giving the cheese a meaty texture; at the same time, controlling the size of the demulsified cut blocks within the range described above will not have an adverse effect on the hardness of the cheese, thus avoiding affecting the texture and taste of the cheese; moreover, controlling the conditions of hot blanching treatment makes the casein in the cheese fully denatured, producing a meaty taste. In addition, through the control of the above-mentioned various means, the shelf life of the obtained cheese is significantly extended.

[0040] The test results show that the cheese product prepared by the present invention has a protein content of more than 40 g / 100 g, a solid content of more than 70 g / 100 g, and is rich in nutrition; the hardness of the product reaches 50-70 N, meeting the requirements, and at the same time has a better beef jerky texture and chewing taste; the shelf life at room temperature reaches more than 3 months, and the shelf life under the low temperature condition of 2-6°C reaches more than 6 months. Description of the Drawings

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0042] Figure 1 It is an apparent schematic diagram of the cheese product obtained before cutting in step S5 of Embodiment 1. Detailed implementation manners

[0043] A method for preparing a beef jerky - type natural cheese, comprising the following steps:

[0044] a) Standardization of raw materials:

[0045] Mix raw milk and membrane - filtered casein and heat them to obtain a standardized raw material;

[0046] b) Sterilization, fermentation, and coagulation:

[0047] After sterilizing the standardized raw material, add a starter culture for fermentation, and then add rennet for coagulation to obtain a coagulum;

[0048] c) Demulsification and whey drainage:

[0049] Cut and demulsify the coagulum, stir and heat it up. When the pH of the whey reaches 5.2 - 5.6, drain the whey to obtain coagulum particles;

[0050] d) Stacking, pressing, and forming:

[0051] Place the coagulum particles in a forming mold for pressing and forming to obtain a formed cheese block;

[0052] The pressure for the pressing and forming is 0.6 - 0.8 MPa, and the time is 24 - 48 h;

[0053] e) Scalding treatment and cooling:

[0054] Place the formed cheese block in a liquid medium for scalding and soaking, and then cool it to obtain a beef jerky - type natural cheese;

[0055] The temperature for the scalding and soaking is 85 - 95 °C, and the time is 3 - 5 h.

[0056] The preparation method of the beef jerky - type natural cheese provided by the present invention first introduces membrane - filtered casein into the raw materials for standardization treatment, and then performs sterilization, fermentation, coagulation, demulsification and whey drainage, stacking and pressing for shaping, heat treatment and cooling. Among them, introducing membrane - filtered casein into the raw materials, controlling the size of the demulsified cut pieces, controlling the conditions of pressing and shaping, and the conditions of heat treatment are crucial. By adding membrane - filtered casein, the content of active casein is increased, and under the action of rennet in subsequent steps, this protein can continue to be hydrolyzed, so that the final cheese product has a high protein content and solid content, endowing the cheese with a meaty texture. At the same time, when the size of the demulsified cut pieces is controlled within the range described above, it will not have an adverse effect on the hardness of the cheese, thus avoiding affecting the texture and taste of the cheese. Moreover, by controlling the conditions of heat treatment, the casein in the cheese is fully denatured, generating a meaty taste. In addition, through the control of the above - mentioned various means, the shelf life of the obtained cheese is significantly extended.

[0057] Regarding step a) : Standardization of raw materials.

[0058] Standardization of raw materials: Mix raw milk and membrane - filtered casein and heat them to obtain standardized raw materials.

[0059] The membrane - filtered casein is a kind of casein produced by membrane - filtration technology, also known as active casein. In the present invention, the type of the membrane - filtered casein is preferably Leprino USA, sourced from Leprino Foods Company in the United States. The addition amount of the membrane - filtered casein is preferably 2wt% - 4wt% of raw milk, and specifically can be 2wt%, 3wt%, 4wt%.

[0060] In the present invention, the heating temperature is preferably 50 - 60°C, and specifically can be 50°C, 51°C, 52°C, 53°C, 54°C, 55°C, 56°C, 57°C, 58°C, 59°C, 60°C. In the present invention, the preferred way of mixing and heating is: first heat the raw milk to the target temperature, then add the membrane - filtered casein, and keep mixing for a certain time at this temperature.

[0061] In the present invention, stirring is preferably accompanied during the heating process. In the present invention, the rotation speed of the stirring is preferably 800 - 1100 rpm, and in some embodiments of the present invention, it is 800 rpm, 900 rpm, 1000 rpm, 1100 rpm. The stirring time is preferably 30 min. After the stirring ends, stop heating to obtain standardized raw materials and proceed to the next step.

[0062] The present invention adds membrane - filtered casein to raw milk and fully hydrates it through heating and stirring, which can increase the content of active casein. Moreover, after adding rennet in subsequent steps, this protein can continue to be hydrolyzed, so that the final cheese product has a high protein content and solid content, endowing the cheese with a meaty texture.

[0063] Regarding step b) : Sterilization, fermentation, and curdling.

[0064] Sterilization, fermentation, and curdling: After sterilizing the standardized raw materials, a starter culture is added for fermentation, and then, rennet is added for curdling to obtain a coagulum.

[0065] In the present invention, the sterilization is preferably pasteurization. More preferably, the sterilization conditions are specifically: holding at 65 °C for 30 min, or holding at 72 °C for 15 s. After the above sterilization, cooling is preferably carried out. The cooling is preferably to cool to 28 - 32 °C, specifically, it can be 28 °C, 29 °C, 30 °C, 31 °C, or 32 °C. Fermentation is carried out after cooling.

[0066] In the present invention, the operation of the fermentation is preferably: first add the starter culture and stir evenly, and then let it stand for fermentation.

[0067] Among them:

[0068] The type of the starter culture is not particularly limited and can be a conventional starter culture in the art, including but not limited to one or more of Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. diacetylactis, and Streptococcus thermophilus. In some embodiments of the present invention, the starter culture is FC - 211 (derived from DSM, which contains both Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris); in some other embodiments of the present invention, the starter culture is CP121 (derived from DSM, which is Streptococcus thermophilus); in some other embodiments of the present invention, the starter culture is SC - 619 (derived from DSM, which contains both Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, and Lactococcus lactis subsp. diacetylactis); in some other embodiments of the present invention, the starter culture is DX - 34A (derived from DSM, which contains both Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, and Lactococcus lactis subsp. diacetylactis); in some other embodiments of the present invention, the starter culture is CH - 200 (derived from DSM, which contains both Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, and Streptococcus thermophilus); in some other embodiments of the present invention, the starter culture is SC - 131 (derived from DSM, which contains both Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, and Streptococcus thermophilus). The above are only examples rather than limitations. In the present invention, the starter culture can be a conventional starter culture in the art and is not limited to the above types. In the present invention, the inoculation amount of the starter culture is preferably 0.005% - 0.03%; in some embodiments of the present invention, the inoculation amount of the starter culture is 0.005% or 0.01%. In the present invention, the conditions of the stirring are not particularly limited as long as the materials can be stirred evenly.

[0069] The temperature of the static fermentation is the same as the temperature of the cooling described above, i.e., 28-32°C, specifically it can be 28°C, 29°C, 30°C, 31°C, 32°C; the time of the static fermentation is preferably 2 h. After the above fermentation, a fermented product is obtained.

[0070] In the present invention, after the above fermentation, rennet is added for curdling.

[0071] In the present invention, the type of the rennet is not particularly limited, and any conventional rennet in the art can be used, preferably one or more of microbial rennet and animal rennet. In some embodiments of the present invention, the rennet is animal rennet MAXIREN1800; the above embodiments are only listed rather than limited, and in the present invention, the rennet is any conventional rennet in the art, not limited to the above types. In the present invention, the time of the curdling is preferably controlled within 40 min. If the curdling time is too long, the curd is not easy to cut, and the whey contained therein will not be discharged smoothly and in time; if the curdling time is too short, the gel strength of the curd is insufficient, and it is easy to break up and not form during cutting. To control the curdling time to 40 min, it can be achieved by controlling the addition amount of the rennet. Different types of rennet have different curdling activities, and the addition amount can be adjusted adaptively; in some embodiments of the present invention, the addition amount of the rennet is 0.0005%, 0.0015%, 0.001%. In the present invention, the temperature of the curdling is the same as the temperature of the cooling described above, i.e., 28-32°C, specifically it can be 28°C, 29°C, 30°C, 31°C, 32°C; that is, after cooling as described above, fermentation and curdling are carried out at this cooling temperature.

[0072] Regarding step c) : Demulsification and whey drainage.

[0073] Demulsification and whey drainage: The coagulum is cut for demulsification, and stirred and heated until the pH of the whey reaches 5.2-5.6, then the whey is discharged to obtain curd granules.

[0074] In the present invention, the cutting for demulsification is to cut the coagulum into small particles of a certain size with a cutting knife; in the present invention, it is preferably to cut the coagulum into milk block particles with a length, width and height of 0.3-0.5 cm each; wherein, the length, width and height of each milk block particle are independently selected from 0.3-0.5 cm; more preferably, the length, width and height of the milk block particles are the same, i.e., cube particle blocks. The size of the cut particles will affect the hardness of the finally produced cheese, and in the present invention, controlling the cut size within the above range can reduce the influence on the hardness of the cheese product and basically will not affect the hardness of the cheese so as not to damage the taste of the cheese.

[0075] In the present invention, after cutting, stirring and heating are carried out. The heating is preferably carried out to 48-55 °C, specifically it can be 48 °C, 49 °C, 50 °C, 51 °C, 52 °C, 53 °C, 54 °C, 55 °C. During the stirring and heating process, the lactic acid produced by the ferment added in the previous step fermenting lactose changes the pH of the system. Taking the whey pH reaching 5.2-5.6 as the end point, when the above pH is reached, stirring and heating are stopped, and the whey is discharged. If the pH value is too high, the acidity of the cheese is insufficient and the cheese flavor is very light. If the pH value is too low, the curd particles will soften, which is not conducive to subsequent pressing and forming. In the present invention, the pH value can specifically be 5.2, 5.3, 5.4, 5.5, 5.6. The present invention has no special limitation on the way of discharging the whey, and it can be carried out according to the conventional operations in the art, such as filtering and discharging the whey with a gauze bag or adding a filter screen at the discharge port of the curd tank to discharge the whey. After the whey is discharged, curd particles are obtained.

[0076] Regarding step d) : Stacking and pressing for forming.

[0077] Stacking and pressing for forming: The curd particles are placed in a forming mold for pressing and forming to obtain a formed cheese block.

[0078] In the present invention, the pressure for the pressing and forming is 0.6-0.8 MPa, specifically it can be 0.6 MPa, 0.7 MPa, 0.8 MPa, and preferably 0.8 MPa. The time for the pressing and forming is 24-48 h, specifically it can be 24 h, 30 h, 36 h, 48 h. Controlling under the above forming pressure and time can make the cheese product have a suitable hardness, which is beneficial to forming the chewing texture of beef jerky. After the above forming, demolding is carried out to obtain a formed cheese block.

[0079] Regarding step e) : Blanching treatment and cooling.

[0080] Blanching treatment and cooling: The formed cheese block is placed in a liquid medium for blanching and soaking, and then cooled to obtain a beef jerky-type natural cheese.

[0081] In the present invention, the liquid medium is preferably water, whey or reconstituted whey liquid. Among them, there is no special limitation on the type of the whey, and it can be the whey discharged in the previous step. In the present invention, there is no special limitation on the dosage ratio of the formed cheese block to the liquid medium, and it is only necessary that the liquid medium can submerge the formed cheese block.

[0082] In the present invention, the temperature of the hot scalding soak is 85-95°C, specifically it can be 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C. Specifically, the liquid medium can be preheated to the above temperature, and then the formed cheese blocks are soaked in the liquid medium. In the present invention, the time of the hot scalding soak is 3-5 h, specifically it can be 3 h, 4 h, 5 h. During the hot scalding soak, the formed cheese blocks are turned over irregularly to ensure uniform hot scalding soak. By hot scalding soak under the above conditions, the casein in the cheese is fully deformed, giving the cheese a meaty texture.

[0083] In the present invention, after the above hot scalding treatment, cooling is carried out. In the present invention, the cooling is preferably to cool to room temperature (15-28°C) or 4°C.

[0084] After cooling, the following treatment is preferably further carried out: cutting the cooled product into the shape of beef jerky with a sterile knife, and then carrying out sterile vacuum packaging to obtain beef jerky-type natural cheese. Among them, the sterile vacuum packaging can specifically be sterile vacuum plastic sealing packaging.

[0085] In the present invention, after obtaining the finished product, storage is carried out. The storage is room temperature storage or low temperature storage. Among them, the temperature of low temperature storage is preferably 2-6°C.

[0086] The present invention also provides a beef jerky-type natural cheese prepared by the preparation method described in the above technical solution.

[0087] For the preparation method of the beef jerky-type natural cheese provided by the present invention, membrane-filtered casein is first introduced into the raw materials for standardization treatment, and then sterilization, fermentation, coagulation, demulsification and whey drainage, stacking and pressing into shape, hot scalding treatment and cooling are carried out. Among them, it is crucial to introduce membrane-filtered casein into the raw materials, control the size of the demulsified cut blocks, control the conditions of pressing into shape and the conditions of hot scalding treatment. By adding membrane-filtered casein, the content of active casein is increased, and under the action of rennet in the subsequent steps, this protein can continue to be hydrolyzed, so that the final cheese product has a higher protein content and solid content, giving the cheese a meaty texture; at the same time, controlling the size of the demulsified cut blocks within the range described above will not have an adverse effect on the hardness of the cheese, thus avoiding affecting the texture and taste of the cheese; controlling the conditions of pressing into shape affects the hardness of the cheese. Through the combination of pressure and time, the coagulated particles are fully fused to form a uniform texture state, and at the same time, more whey is discharged to make the produced cheese reach a certain hardness. If the hardness does not meet the requirements, the cheese will absorb some moisture during the subsequent hot scalding, resulting in a poor meaty texture of the cheese obtained after the final cooling; moreover, controlling the conditions of hot scalding treatment makes the casein in the cheese fully denatured, producing a meaty texture. In addition, through the control of the above-mentioned various means, the shelf life of the obtained cheese is significantly extended.

[0088] The beef jerky - type natural cheese provided by the present invention has the following beneficial effects:

[0089] 1. The cheese product of the present invention has a high protein content and solid content, and is rich in nutrition;

[0090] 2. The cheese product of the present invention has the texture and chewing taste of beef jerky, and is an excellent substitute and nutritious food for beef jerky eaters;

[0091] 3. Compared with conventional cheese, the shelf life of the cheese product provided by the present invention is significantly extended;

[0092] 4. The beef jerky - type natural cheese provided by the present invention is convenient to carry and is a new type of natural cheese category.

[0093] The test results show that for the cheese product prepared by the present invention, the protein content reaches more than 40 g / 100 g, the solid content reaches more than 70 g / 100 g, and it is rich in nutrition; the hardness of the product reaches 50 - 70 N, meeting the requirements, and at the same time has a better texture and chewing taste of beef jerky; the shelf life reaches more than 3 months at room temperature and more than 6 months under the low - temperature condition of 2 - 6 °C.

[0094] To further understand the present invention, the preferred implementation schemes of the present invention will be described below in conjunction with embodiments. However, it should be understood that these descriptions are only for further explaining the features and advantages of the present invention, rather than limiting the claims of the present invention.

[0095] In the following embodiments, the membrane - filtered casein is Leprino USA. Room temperature refers to 25 °C.

[0096] Example 1

[0097] S1. Raw material standardization:

[0098] Heat the raw milk to 55 °C, add membrane - filtered casein accounting for 2 wt% of the raw milk usage, and stir at 1000 rpm for 30 min to obtain the standardized raw material.

[0099] S2. Sterilization:

[0100] Heat the standardized raw material to 72 °C and keep it warm for 15 s. Then, cool it to 28 °C, add the starter - FC - 211 from DSM (containing Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris), with an inoculation amount of 0.01%, stir evenly, and then let it stand and ferment at this temperature for 2 h. Then, at this temperature, add rennet MAXIREN1800, with an addition amount of 0.0015%, to make the coagulation time 40 min to obtain the coagulum.

[0101] S3. Demulsification and whey drainage:

[0102] Cut the coagulum for demulsification, and cut it into milk cube particles with a length, width and height of 0.4 cm. Then, while stirring, heat it to 50 °C. When the pH of the whey reaches 5.4, stop heating and stirring, and remove the whey to obtain curd particles.

[0103] S4. Stacking and pressing for forming:

[0104] Place the obtained curd particles in a forming mold for pressing and forming. The pressure is 0.8 MPa and the time is 30 h. Then, demold to obtain a formed cheese block.

[0105] S5. Blanching treatment and cooling:

[0106] Transfer the formed cheese block into a 90 °C whey solution and soak it for 3 h, turning it over irregularly during this period. Then, take out the cheese block and cool it to room temperature. Cut it into strips, package the finished product, and transfer it to be stored under room temperature conditions.

[0107] Among them, for the appearance of the cheese product after blanching and cooling and before cutting in step S5, see Figure 1 , Figure 1 which is the schematic diagram of the appearance of the cheese product obtained before cutting in step S5 of Example 1. It can be seen that the product has the appearance and texture of beef jerky.

[0108] Example 2

[0109] S1. Raw material standardization:

[0110] Heat the raw milk to 55 °C, add membrane-filtered casein accounting for 3 wt% of the raw milk consumption, and stir at 1100 rpm for 30 min to obtain a standardized raw material.

[0111] S2. Sterilization:

[0112] Heat the standardized raw material to 72 °C and keep it warm for 15 s. Then, cool it to 32 °C, add a starter - CP121 (Streptococcus thermophilus) from DSM, with an inoculation amount of 0.005%, stir evenly, and then let it stand and ferment at this temperature for 2 h. Then, at this temperature, add rennet MAXIREN1800, with an addition amount of 0.001%, to make the coagulation time 40 min to obtain a coagulum.

[0113] S3. Demulsification and whey removal:

[0114] Cut the coagulum for demulsification, and cut it into milk cube particles with a length, width and height of 0.4 cm. Then, while stirring, heat it to 50 °C. When the pH of the whey reaches 5.4, stop heating and stirring, and remove the whey to obtain curd particles.

[0115] S4. Stacking and pressing for forming:

[0116] Place the obtained curd particles in a forming mold for pressing and forming at a pressure of 0.8 MPa for 24 h. Then, demold to obtain formed cheese blocks.

[0117] S5. Blanching treatment and cooling:

[0118] Transfer the formed cheese blocks into a 95 °C whey solution and soak for 3 h, turning them over irregularly during this period. Then, take out the cheese blocks and cool them to room temperature. Cut them into strips, package the finished products, and transfer them to be stored under room temperature conditions.

[0119] Example 3

[0120] S1. Raw material standardization:

[0121] Heat the raw milk to 55 °C, add 4 wt% of membrane-filtered casein based on the amount of raw milk used, and stir at 800 rpm for 30 min to obtain standardized raw materials.

[0122] S2. Sterilization:

[0123] Heat the standardized raw materials to 72 °C and hold for 15 s. Then, cool to 28 °C, add a starter culture - SC-619 from DSM (containing Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. diacetylactis) with an inoculation amount of 0.01%, stir evenly, and then let it stand and ferment at this temperature for 2 h. Then, at this temperature, add rennet MAXIREN1800 with an addition amount of 0.001% to make the coagulation time 40 min to obtain a coagulum.

[0124] S3. Demulsification and whey drainage:

[0125] Cut and demulsify the coagulum into milk block particles with a length, width, and height of 0.4 cm each. Then, while stirring, heat to 50 °C. When the pH of the whey reaches 5.4, stop heating and stirring, and drain the whey to obtain curd particles.

[0126] S4. Stacking and pressing forming:

[0127] Place the obtained curd particles in a forming mold for pressing and forming at a pressure of 0.8 MPa for 36 h. Then, demold to obtain formed cheese blocks.

[0128] S5. Blanching treatment and cooling:

[0129] Transfer the formed cheese blocks into a 95 °C whey solution and soak for 4 h, turning them over irregularly during this period. Then, take out the cheese blocks and cool them to room temperature. Cut them into strips, package the finished products, and transfer them to be stored under room temperature conditions.

[0130] The preparation conditions, product characteristics, and shelf life of Examples 1 to 3 are shown in Table 1.

[0131] Table 1 Preparation Conditions, Product Characteristics and Shelf Life of Examples 1 - 3

[0132] Pressing and forming time / h Blanching temperature / °C Storage conditions Shelf life / month Example 1 30 90 Normal temperature 3 Example 2 24 95 Normal temperature 4 Example 3 36 95 Normal temperature 5

[0133] It can be seen that as the pressing time extends and the blanching temperature increases, the shelf life of the product during storage at room temperature is extended. When the pressing forming time is 36 h and the blanching temperature is 95 °C, the shelf life of the product during storage at room temperature reaches the best.

[0134] Example 4

[0135] S1. Standardization of raw materials:

[0136] Heat raw milk to 55 °C, add 2 wt% of membrane - filtered casein based on the amount of raw milk, stir at 800 rpm for 30 min to obtain standardized raw materials.

[0137] S2. Sterilization:

[0138] Heat the standardized raw materials to 65 °C and keep warm for 30 min. Then, cool to 32 °C, add the starter culture - DX - 34A from DSM (containing Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. diacetylactis), with an inoculation amount of 0.01%, stir evenly, and then let it stand and ferment at this temperature for 2 h. Then, at this temperature, add rennet MAXIREN1800 with an addition amount of 0.001% to make the coagulation time 40 min to obtain a coagulum.

[0139] S3. Demulsification and whey drainage:

[0140] Cut the coagulum for demulsification into milk block particles with a length, width and height of 0.4 cm each. Then, while stirring, heat up to 50 °C. When the pH of the whey reaches 5.6, stop heating and stirring, and drain the whey to obtain curd particles.

[0141] S4. Stacking and pressing forming:

[0142] Place the obtained curd particles in a forming mold for pressing forming, with a pressure of 0.8 MPa and a time of 24 h. Then, demold to obtain formed cheese blocks.

[0143] S5. Blanching treatment and cooling:

[0144] Transfer the formed cheese blocks into an 85 °C whey solution, soak for 5 h, and turn them over irregularly during this period. Then, take out the cheese blocks, cool to 4 °C, cut them into strips, package the finished products, and transfer them to be stored at 3 °C.

[0145] Example 5

[0146] S1. Standardization of raw materials:

[0147] Heat the raw milk to 55 °C, add membrane-filtered casein accounting for 3 wt% of the raw milk usage, stir at 900 rpm for 30 min to obtain a standardized raw material.

[0148] S2. Sterilization:

[0149] Heat the standardized raw material to 65 °C and keep it warm for 30 min. Then, cool it to 28 °C, add a starter culture - CH-200 from DSM (containing Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Streptococcus thermophilus), with an inoculation amount of 0.005%, stir evenly, and then let it stand and ferment at this temperature for 2 h. Then, at this temperature, add rennet MAXIREN1800, with an addition amount of 0.0005%, to make the coagulation time 40 min to obtain a coagulum.

[0150] S3. Demulsification and whey drainage:

[0151] Cut the coagulum for demulsification into milk block particles with a length, width, and height of 0.4 cm each. Then, while stirring, heat it to 50 °C. When the whey pH reaches 5.6, stop heating and stirring, drain the whey to obtain curd particles.

[0152] S4. Stacking and pressing for forming:

[0153] Place the obtained curd particles in a forming mold for pressing and forming, with a pressure of 0.8 MPa and a time of 30 h. Then, demold to obtain formed cheese blocks.

[0154] S5. Scalding treatment and cooling:

[0155] Transfer the formed cheese blocks into a 90 °C whey solution, soak for 3 h, and turn them over irregularly during this period. Then, take out the cheese blocks, cool them to 4 °C, cut them into strips, package the finished products, and transfer them to be stored at 3 °C.

[0156] Example 6

[0157] S1. Raw material standardization:

[0158] Heat the raw milk to 55 °C, add membrane-filtered casein accounting for 4 wt% of the raw milk usage, stir at 1000 rpm for 30 min to obtain a standardized raw material.

[0159] S2. Sterilization:

[0160] Heat the standardized raw materials to 65°C and keep them warm for 30 min. Then, cool them to 28°C, add the starter culture - SC-131 from DSM (containing Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Streptococcus thermophilus), with an inoculation amount of 0.005%, stir evenly, and then let it stand and ferment at this temperature for 2 h. Then, at this temperature, add rennet MAXIREN 1800, with an addition amount of 0.001%, to make the coagulation time 40 min, and obtain a coagulum.

[0161] S3. Demulsification and whey drainage:

[0162] Cut the coagulum to demulsify it, cut it into milk cube particles with a length, width, and height of 0.4 cm each. Then, while stirring, heat it to 50°C. When the pH of the whey reaches 5.6, stop heating and stirring, drain the whey, and obtain coagulated milk particles.

[0163] S4. Stacking, pressing, and forming:

[0164] Place the obtained coagulated milk particles in a forming mold for pressing and forming, with a pressure of 0.8 MPa and a time of 36 h. Then, demold to obtain formed cheese blocks.

[0165] S5. Blanching treatment and cooling:

[0166] Transfer the formed cheese blocks into a 95°C whey solution, soak them for 5 h, and turn them over irregularly during this period. Then, take out the cheese blocks and cool them to 4°C, cut them into strips, package the finished products, and transfer them to be stored at 3°C.

[0167] See Table 2 for the preparation conditions, product characteristics, and shelf life of Examples 4 to 6.

[0168] Table 2 Preparation conditions, product characteristics, and shelf life of Examples 4 to 6

[0169] Pressing and forming time / h Blanching temperature / °C Storage conditions Shelf life / month Example 4 24 85 3℃ 6 Example 5 30 90 3℃ 7 Example 6 36 95 3℃ 9

[0170] It can be seen from the test results in Table 2 that, similar to the rule in Table 1, as the pressing time extends and the blanching temperature increases, the low-temperature storage shelf life of the product is extended. When the pressing and forming time is 36 h and the blanching temperature is 95°C, the low-temperature storage shelf life of the product reaches the best. At the same time, by comparing Table 1 and Table 2, it can be seen that the low-temperature storage condition can extend the product shelf life compared with the normal-temperature storage condition.

[0171] Example 7

[0172] Implement according to the process of Example 4, except that the addition amounts of membrane-filtered casein are set to 0.5%, 2% (corresponding to Example 4), 3%, 4%, and 6% respectively. The obtained products are denoted as 7-1, 7-2 (corresponding to Example 4), 7-3, 7-4, and 7-5 respectively.

[0173] Perform various characteristic tests on the above products, including: protein content, solid content, hardness, taste, and low-temperature shelf life. The results are shown in Table 3.

[0174] Among them, the instrument used for hardness testing is a texture analyzer Shimadzu EZ TEST (Shimadzu Corporation (China) Co., Ltd.). The descriptive words for texture and taste are based on the ISO 13299 rapid descriptive analysis test method, and the sample size is 12 internal trained panel members.

[0175] Table 3 Product test results in Example 7

[0176]

[0177] It can be seen from the test results in Table 3 that for samples 7-2 to 7-4 within the range of 2% to 4% of the membrane-filtered casein addition amount of the present invention, they have a relatively high protein content and solid content. The hardness range of the products is 50-70 N, which is neither too low nor too high and reaches an appropriate level, facilitating a better taste; they have the texture and chewing taste of beef jerky, as well as a relatively long shelf life, and the comprehensive effect of the products is better. While for sample 7-1 with too low membrane-filtered casein addition amount and sample 7-4 with too high addition amount, the comprehensive effect is relatively poor.

[0178] Comparative Example 1

[0179] Implement according to the process of Example 4, except that the blanching temperatures are changed to 75°C and 100°C respectively, and the obtained samples are denoted as comparative samples 1-1 and 1-2 respectively.

[0180] Perform various characteristic tests on the obtained comparative samples according to the test method of Example 7, and compare with the product of Example 4. The results are shown in Table 4.

[0181] Table 4 Product test results in Comparative Example 1

[0182] Sample Blanching temperature / °C Hardness Texture, taste Shelf life / month Control sample 1-1 75 50N The texture is firm and the meaty texture is slightly weak 5 Control sample 1-2 100 48N The texture is not firm and the meaty texture is poor 4 Example 4 85 52N The texture is firm and the meaty taste is good 6

[0183] It can be seen from the test results in Table 4 that compared with Example 4, the comprehensive effect of the two comparative samples is significantly worse; among them, the shelf life of both comparative samples is reduced; the taste of comparative sample 1-1 is poor, and the hardness of comparative sample 1-2 is too low, and the texture and taste are relatively poor, mainly because the blanching is under boiling conditions, and more whey or water enters the cheese, thus affecting the texture and meaty texture of the cheese. This proves that when the present invention controls the blanching temperature at 85-95°C, it is beneficial to obtain a hardness level that meets the requirements (50-70 N), has a better texture and chewing taste of beef jerky, as well as a relatively long shelf life, and the comprehensive effect of the product is better; while when the blanching temperature is too low or too high, the comprehensive effect of the product will be reduced.

[0184] Comparative Example 2

[0185] The process of Example 4 was implemented, except that the molding pressures were changed to 0.4 MPa and 1.2 MPa respectively, and the obtained samples were denoted as Comparative Sample 2-1 and Comparative Sample 2-2 respectively.

[0186] The obtained comparative samples were tested for various properties according to the testing method of Example 7 and compared with the product of Example 4. The results are shown in Table 5.

[0187] Table 5 Test Results of the Products in Comparative Example 2

[0188] Sample Forming pressure / MPa Hardness Texture, taste Shelf life / month Control sample 2-1 0.4 40N The texture is not very firm and the meaty taste is not good 3 Control sample 2-2 1.2 75N The texture is too hard and the meaty texture is a bit excessive 8 Example 4 0.8 52N The texture is firm and the meaty texture is good 6

[0189] It can be seen from the test results in Table 5 that compared with Example 4, the comprehensive effects of the two comparative samples are significantly worse; among them, the hardness of Comparative Sample 2-1 is too low, the texture and taste are not good, and the shelf life is short; the hardness of Comparative Sample 2-2 is too high, the texture is too hard, affecting the taste. This proves that when the molding pressure of the present invention is controlled at 0.6 - 0.8 MPa, it is beneficial to obtain a hardness level that meets the requirements (50 - 70 N), has a better texture and chewing taste of beef jerky, and ensures a longer shelf life, and the comprehensive effect of the product is better; when the molding pressure is too low or too high, the comprehensive effect of the product will be reduced.

[0190] Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above examples is only used to help understand the method and its core idea of the present invention, including the best mode, and also enables any person skilled in the art to practice the present invention, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention. The protection scope of this invention patent is defined by the claims and may include other embodiments that can be conceived by those skilled in the art. If these other embodiments have structural elements similar to the literal description of the claims, or if they include equivalent structural elements that have no substantial difference from the literal description of the claims, then these other embodiments should also be included within the scope of the claims.

Claims

1. A method for preparing a beef jerky-type natural cheese, characterized in that, It includes the following steps: a) Raw material standardization: Mix and heat raw milk and membrane-filtered casein to obtain standardized raw materials; The addition amount of the membrane-filtered casein is 2wt% - 4wt% of the raw milk; The heating temperature is 50 - 60°C; Stirring is accompanied during the heating process; The rotation speed of the stirring is 800 - 1100 rpm, and the time is 40 min; b) Sterilization, fermentation, and curdling: After sterilizing the standardized raw materials, cool them, add a starter and stir evenly, then let it stand for fermentation. After that, add rennet for curdling to obtain a coagulum; The cooling is to cool to 28 - 30°C; The temperature for the standing fermentation is 28 - 30°C, and the time is 2 h; The temperature for the curdling is 28 - 30°C; c) Demulsification and whey drainage: Cut and demulsify the coagulum, and stir and heat up. When the pH of the whey reaches 5.2 - 5.6, drain the whey to obtain curd granules; The cut and demulsification is to cut the coagulum into milk cubes with a length, width, and height of 0.3 - 0.5 cm; the milk cubes are cube-shaped particles; The heating up is to heat up to 48 - 55°C; d) Stacking, pressing, and forming: Place the curd granules in a forming mold for pressing and forming to obtain formed cheese blocks; The pressure for the pressing and forming is 0.6 - 0.8 MPa, and the time is 24 - 48 h; e) Blanching treatment and cooling: Place the formed cheese blocks in a liquid medium for blanching and soaking, and then cool to obtain beef jerky-type natural cheese; The temperature for the blanching and soaking is 85 - 95°C, and the time is 3 - 5 h.

2. The preparation method according to claim 1, characterized in that, In step e), the liquid medium is water or whey.

3. The preparation method according to claim 1, wherein In step b), the sterilization conditions are: holding at 65°C for 30 min, or holding at 72°C for 15 s.

4. The preparation method according to claim 1, wherein The starter includes one or more of Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. diacetylactis, and Streptococcus thermophilus.

5. The preparation method according to claim 1, wherein In step b), the time for the curdling is 40 min; The rennet includes one or more of microbial rennet and animal rennet.

6. The preparation method according to claim 1, characterized in that, In step e), the cooling is to cool to room temperature or 4°C; After the cooling, it further includes: cutting the cooled product into the shape of beef jerky with a sterile knife, and then performing sterile vacuum packaging to obtain beef jerky-type natural cheese.

7. A beef jerky-type natural cheese prepared by the preparation method according to any one of claims 1 - 6.

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