Preparation method of low-heat-shrinkage sausage casing for fermented flavor sausage and prepared sausage casing

Abstract

The invention relates to a preparation method of a low-heat-shrinkage sausage casing for a fermented flavor sausage and the prepared sausage casing. The preparation method comprises the following steps: an artificial aerated collagen casing dried at a low temperature is guided to a heat transfer unit, the artificial aerated collagen casing has water accounting for 5-15% of the total weight of the casing, the thermal decomposition risk of the obtained thermal shrinkage casing is reduced, and the artificial aerated collagen casing has internal gas pressure of 20-1000 Pa; and at the temperature higher than the shrinkage temperature of the collagen casing, the heat transfer unit transfers high heat energy to the casing instantly so as to obtain the artificial collagen casing with low heat shrinkage. The method has the advantages that the casing is subjected to high-temperature instant heat treatment through the heat transfer unit, the moisture and the internal gas pressure of the casing are controlled, and the thermal decomposition risk of the casing is reduced, so that the artificial collagen casing with low thermal shrinkage is obtained; the casing subjected to high-temperature instant heat treatment is heat-resistant, and the heat shrinkage of the casing is reduced when the casing is applied, so that the shrinkage rate of the fermented flavor sausage is small after continuous high-temperature fermentation and air drying.

Description

Technical Field

[0001] The invention relates to the technical field of collagen casing processing, and in particular to a method for preparing a low-heat shrinkage casing for fermented flavor sausages and the prepared casing. Background Art

[0002] Artificial collagen casings are an indispensable edible packaging material in the sausage preparation process. The casings currently on the market are low-temperature dried and formed casings. The existing preparation method is to form casings with high water content through low-temperature drying to obtain the final product, specifically wet casing extrusion (extrusion process) → low-temperature drying and forming (forming process below 100°C) → winding to obtain the final product.

[0003] The main defects of existing low-temperature drying and forming casings are: the casings are not heat-resistant, the casings have high thermal shrinkage when used at high temperatures, deformation is serious, and the sausage length shrinks significantly. The casings for fermented flavor sausages need to undergo continuous high-temperature fermentation and air-drying treatment when used. The existing casings have high thermal shrinkage, and the length of the fermented flavor sausages produced is significantly shortened and the shrinkage length is inconsistent. When the fermented flavor sausages are cut into fixed lengths, the tail sections are of different lengths, which is not conducive to processing, increasing costs and reducing profits. It is necessary to provide a method for preparing low-heat shrinkage casings for fermented flavor sausages and the casings obtained to reduce the thermal shrinkage of collagen casings when used at high temperatures and avoid defects in the application process. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for preparing a low heat shrinkage casing for fermented flavored sausages and the casing obtained, which can solve the problems in the prior art that the collagen casing has high heat shrinkage when used at high temperatures and the sausage length shrinks significantly after undergoing a continuous high-temperature fermentation and air-drying process.

[0005] In order to solve the above technical problems, the technical solution of the present invention is: guiding the low-temperature dried aerated collagen casing to a heat transfer unit, wherein the aerated collagen casing has a moisture content of 5%-15% of the total weight of the casing, so as to reduce the risk of thermal decomposition of the obtained heat-shrinkable casing, and the aerated collagen casing has an internal gas pressure of 20 Pa-1000 Pa; At a temperature higher than the shrinkage temperature of the collagen casing, the heat transfer unit instantly transfers high heat energy to the casing, and the casing is humidified after high-temperature heat treatment to obtain an artificial collagen casing with low thermal shrinkage.

[0006] The method for preparing a low heat shrink collagen casing for fermented flavored sausage comprises the following steps: S1, guiding the low-temperature dried aerated collagen casing to a heat transfer unit, wherein the heat transfer unit comprises a high-temperature annular infrared heater, and the high-temperature annular infrared heater supplies heated high-temperature air to perform instant high-temperature uniform heat treatment on the casing, wherein the high-temperature heat treatment temperature is 550°C-650°C, the treatment time is 0.1 sec, and the periphery of the aerated casing is heat-shrunk; S2, the casing after high temperature instantaneous heat treatment is flattened by a flattening conveying roller composed of a stainless steel roller and a flattening roller; S3, humidifying the flattened casings online so that the moisture content of the casings is adjusted to 18% relative to the total weight of the casings, and the humidification is achieved by a humidifier; S4, conveying the heat-treated and humidified casing to the winding unit, and after winding, entering the shrinking unit for shrinking.

[0007] Furthermore, in step S1, before heat treatment, the moisture content of the casing is adjusted to 7% to 13% relative to the total weight of the casing, and before high-temperature heat treatment, the gas pressure inside the inflated collagen casing is 50 Pa to 900 Pa.

[0008] Furthermore, in the step S1, during the high temperature heat treatment, the gas pressure inside the aerated collagen casing is 100 Pa to 800 Pa.

[0009] The present invention also provides a casing prepared by the method for preparing the low heat shrinkage collagen casing for fermented flavor sausages.

[0010] The advantages of the present invention are: during the casing manufacturing process, the casing is subjected to instantaneous high-temperature heat treatment by a heat transfer unit, the casing thermal stress is released in advance, the casing moisture and internal gas pressure are controlled, and the risk of thermal decomposition of the casing is reduced, so as to obtain a collagen casing with low thermal shrinkage, and the shrinkage rate of the fermented flavor sausage is small after continuous high-temperature fermentation and air drying; The method can be applied to chemically cross-linked collagen casings extruded from bovine, porcine, ovine or any other fibrous collagen source (including mixtures thereof), and the casings can be subjected to an instantaneous high temperature heat treatment before being flattened. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the preparation equipment of the present invention; Figure 2 The figure is a comparison of fermented flavor sausages made from casings that are not subjected to instantaneous high temperature heat treatment in the prior art and casings subjected to instantaneous high temperature heat treatment in the present invention. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. The following embodiments can enable technicians in this field to understand the present invention more comprehensively, but the present invention is not limited to the scope of the embodiments.

[0013] like Figure 1 As shown, this specific embodiment adopts the following technical scheme: a method for preparing a low heat shrinkage collagen casing for fermented flavored sausages, comprising the following steps: S1. The inflated collagen casing 1 after low-temperature drying and forming (dried below 100°C) is guided to the heat transfer unit 2 through a conveying roller pair. The heat transfer unit 2 includes a high-temperature annular infrared heater. The high-temperature annular infrared heater provides high-temperature heat radiation to perform instantaneous high-temperature heat treatment on the casing. The high-temperature heat treatment temperature is 550°C-650°C, the treatment time is 0.1Sec, and the high-speed production line during high-temperature heat treatment is 10000m / hour to ensure that the casing passes through the high-temperature heater at a high speed.

[0014] The heat transfer unit 2 instantly transfers high heat energy to the casing. The heat energy is transferred to the surface of the collagen casing by infrared radiation, and the periphery of the inflated collagen casing is thermally contracted.

[0015] The above-mentioned air-filled collagen casing 1 is any chemically cross-linked collagen casing extruded from cattle, pigs, sheep or any other fibrous collagen source (including mixtures thereof). The higher the degree of cross-linking, the less likely it is to shrink by heat. Severely cross-linked collagen casings require higher infrared radiation temperature than other cross-linked collagen casings, and long contact time should be avoided to avoid excessive collagen decomposition.

[0016] The aerated collagen casing 1 before heat treatment has a moisture content of 5%-15% of the total weight of the casing. Preferably, the moisture content of the casing is adjusted to 7% to 13% relative to the total weight of the casing to reduce the risk of thermal decomposition of the resulting heat-shrinkable casing. The aerated collagen casing has an internal gas pressure of 20 Pa to 1000 Pa. Preferably, during high-temperature heat treatment, the internal gas pressure of the aerated collagen casing is 50 Pa to 900 Pa. More preferably, the internal gas pressure of the aerated collagen casing is 100 Pa to 800 Pa.

[0017] At a temperature higher than the shrinkage temperature of the collagen casing, the heat transfer unit 2 instantly transfers high heat energy to the casing and controls the moisture and internal gas pressure of the casing to reduce the risk of thermal decomposition of the casing, so as to obtain an artificial collagen casing with low thermal shrinkage. The temperature of the air flow passing through the high-temperature heat treatment fan is much higher than the shrinkage temperature of the casing, and its contact time is adjusted to be as short as possible to avoid excessive thermal decomposition of the collagen casing.

[0018] S2. After the high-temperature instantaneous heat treatment, the casing is flattened by a flattening conveyor roller 3 composed of a stainless steel roller and a flattening roller. A diameter laser measuring unit (not shown) is designed at the front end of the flattening conveyor roller to adjust the inflation pressure before the instantaneous high-temperature heat treatment, thereby adjusting the diameter of the straight casing.

[0019] S3, humidifying the flat casing 4 after being flattened online so that the moisture content of the casing is adjusted to 18% relative to the total weight of the casing, and the humidification is achieved by a humidifier 5.

[0020] The humidification amount of humidifier 5 is mainly controlled by adjusting the pump speed of the humidifier. The humidity test of the casing is tested by an offline heating balance. It is heated at 110℃ for 5 minutes, and the weight of the lost water is the percentage of the original total weight, which is the humidity. The pump speed needs to be adjusted according to the offline humidity test results. The casing is humidified by 18%. On the one hand, it improves the plasticity of the casing, which is beneficial to the subsequent shrinking process. On the other hand, it improves the toughness of the casing and makes it less brittle, which is beneficial to the filling application of the casing.

[0021] S4, conveying the heat-treated and humidified casing to the winding unit 6, the winding machine rotates, the casing is wound into a roll, and finally the rolled casing is unloaded, and the roll is put into the shrinking production line to start the shrinking process, pleating and forming into a tubular product.

[0022] The casing prepared by the above method for preparing low heat shrinkage collagen casing for fermented flavor sausage has good heat resistance, reduced heat shrinkage during use, and is not easy to deform. The fermented flavor sausage made of the casing has a small shrinkage rate after continuous high-temperature fermentation and air drying.

[0023] Embodiment 1: The STIX-N products with a diameter of 15 mm were subjected to instantaneous high-temperature heat treatment to obtain low-heat shrinkage casings for fermented flavor sausages: a high-temperature annular infrared heater was added to the production line of STIX-N15 ordinary casings, and the casings dried at low temperature were passed through the high-temperature annular infrared heater at a speed of 10,000 m / h. The high-temperature annular infrared heater instantly and evenly heated the casings at a temperature of 650°C and a heating length of 0.27 m. After the high-temperature heat treatment, the casings passed through the flattening conveyor roller at 94°C. The casing rotates at 30 m / h and the processing speed is 10,000 m / h. The processing speed refers to the speed of the casing before entering the high-temperature annular infrared heater. The inflation pressure of the casing before the flattening conveyor roller 3 is 500 Pa. The diameter laser measurement unit before the flattening conveyor roller 3 captures the desired inflation diameter of the casing. After passing through the flattening conveyor roller 3, the gas in the casing is eliminated, the casing is flattened, and the caliber of the casing remains unchanged. The flat casing passes through the humidifier 5, and the humidification humidity of the casing is controlled at 18%, which is convenient for subsequent winding and shrinking. The humidified casing is wound into a roll by the winding unit, and then the casing roll is shrunk to obtain the final product. The high-temperature annular infrared heater applies temperature, and the casing shrinks in advance. The resulting casing has a very small thermal shrinkage rate in the fermentation process.

[0024] Example 2: This Example 2 is the same as Example 1 in other steps, except that: the flattening conveyor roller rotates at 9460 m / h, the processing speed is 10000 m / h, the inflation pressure of the casing before the flattening conveyor roller 3 is 470 Pa, and the temperature applied by the high-temperature annular infrared heater is 600°C.

[0025] Example 3: This Example 3 is the same as Example 1 in other steps, except that: the flattening conveyor roller rotates at 9520 m / h, the processing speed is 10000 m / h, the inflation pressure of the casing before the flattening conveyor roller 3 is 440 Pa, and the temperature applied by the high-temperature annular infrared heater is 550°C.

[0026] Comparative Example 1: The commercially available STIX-N casing of DeFle with a diameter of 15 mm is a conventionally produced straight collagen casing.

[0027] The casings prepared in Examples 1-3 and the casings of Comparative Example 1 were subjected to application tests, and the casings of Examples 1-3 and Comparative Example 1 were used to make fermented and air-dried sausages, respectively. The meat filling formulas were shown in Table 1.

[0028] raw material Proportion% beef 63.31 pork 16.66 Fat 16.03 granulated sugar 1 Nitrite 1 spices 1 glucose 0.5 Minced garlic 0.33 Beef flavor 0.15 Lactic acid starter 0.02 Total 100 Table 1 The sausages were made as follows: first, beef, pork, and fat were minced under the rotation of a suitable blade, and then sugar, salt, spices, garlic paste, essence, and fermentation agent were added, and the mixture was evenly and fully stirred. Finally, the minced meat was vacuum degassed for 10 minutes at a suitable stirring speed, and the casing samples of the comparative example and embodiments 1, 2, and 3 of the present invention were filled with the fermented flavored sausage minced meat on a Handtmann VF620 vacuum filler, and the sausages were distributed and connected into sausage chains consisting of 50g of sausages each by an automatic filling twisting and hanging rod machine. All samples were resistant to filling, portioning, and connection without causing interruption, and then the sausages were hung on a cart and pushed into a fermentation heating furnace for treatment. The fermentation heating process is shown in Table 2.

[0029] step Fermentation process Temperature / ℃ Time / Hour humidity / % 1 dry 38 0.4 0 2 Fermentation 38 14 95 3 heating 50 0.5 60 4 heating 60 0.5 50 5 dry 60 0.3 30 6 dry 63 0.3 39 7 dry 68 0.3 41 8 dry 74 0.3 44 9 dry 79 0.4 40 10 dry 82 0.4 40 11 dry 85 0.1 40 12 Spray 20 0.1 \ 13 exhaust \ 0.25 \ Table 2 All fermented flavor sausages were resistant to the fermentation process without producing waste. After fermentation, the shrinkage rate of the sausage fermentation was measured. The casings prepared in Examples 1-3 and the casings of Comparative Example 1 were compared for their pre-heat shrinkage rates, as well as the shrinkage rates of the sausages after fermentation and air-drying. The results are shown in Table 3.

[0030] Table 3 From the above comparison results, it can be seen that the heat shrinkage rate of the fermented and air-dried sausages made from the casings of Examples 1-3 after instantaneous high-temperature heat treatment is significantly lower than that of the comparative example. Figure 2 As shown in the right side of the figure, the fermented and air-dried sausage made from the casing of the comparative example is as follows Figure 2 Shown on the left.

[0031] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for preparing a low heat shrink collagen casing for fermented flavored sausages, characterized in that: The low-temperature dried aerated collagen casing is guided to a heat transfer unit, wherein the aerated collagen casing has a moisture content of 5% to 15% of the total weight of the casing, so as to reduce the risk of thermal decomposition of the obtained heat-shrinkable casing, and the aerated collagen casing has an internal gas pressure of 20 Pa to 1000 Pa; At a temperature higher than the shrinkage temperature of the collagen casing, the heat transfer unit instantly transfers high heat energy to the casing, and the casing is humidified after high-temperature heat treatment to obtain an artificial collagen casing with low thermal shrinkage.

2. The method for preparing the low heat shrinkage collagen casing for fermented flavored sausage according to claim 1, characterized in that: The following steps are involved: S1, guiding the low-temperature dried aerated collagen casing to a heat transfer unit, wherein the heat transfer unit comprises a high-temperature annular infrared heater, and the high-temperature annular infrared heater supplies heated high-temperature air to perform instant high-temperature uniform heat treatment on the casing, wherein the high-temperature heat treatment temperature is 550°C-650°C, the treatment time is 0.1 sec, and the periphery of the aerated casing is heat-shrunk; S2, the casing after high temperature instantaneous heat treatment is flattened by a flattening conveying roller composed of a stainless steel roller and a flattening roller; S3, humidifying the flattened casings online so that the moisture content of the casings is adjusted to 18% relative to the total weight of the casings, and the humidification is achieved by a humidifier; S4, conveying the heat-treated and humidified casing to the winding unit, and after winding, entering the shrinking unit for shrinking.

3. The method for preparing the low heat shrinkage collagen casing for fermented flavored sausage according to claim 2, characterized in that: In the step S1, before the heat treatment, the moisture content of the casing is adjusted to 7% to 13% relative to the total weight of the casing, and before the high-temperature heat treatment, the gas pressure inside the inflated collagen casing is 50 Pa to 900 Pa.

4. The method for preparing a low heat shrinkage collagen casing for fermented flavored sausage according to claim 2, characterized in that: In the step S1, during the high temperature heat treatment, the gas pressure inside the aerated collagen casing is 100 Pa to 800 Pa.

5. The casing prepared by the method for preparing the low heat shrink casing for fermented flavor sausage according to any one of claims 1 to 4.

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