Frozen bamboo shoot with crispness and its production process

Abstract

The application discloses quick-frozen crisp bamboo shoots and a production process thereof, which comprises the following steps: peeling bamboo shoots picked, carrying out bleaching and boiling after peeling, adding a treating agent acetic acid in the bleaching and boiling process, carrying out fixation after the bleaching and boiling, adding a crispness-keeping agent calcium lactate in the fixation process, carrying out clothes removing treatment quickly after the fixation, carrying out quick cooling and soaking of the bamboo shoots after the clothes removing treatment by using a crispness-keeping agent tannic acid solution, carrying out precooling treatment of the bamboo shoots after the soaking, and quickly freezing the bamboo shoots after the precooling treatment until the surface temperature of the bamboo shoots is less than-35 DEG C; and the preparation of the quick-frozen bamboo shoots is completed. The bamboo shoots are treated by the treating agent and the composite crispness-keeping agent, the bamboo shoots are kept crisp after thawing by the synergistic reaction between the crispness-keeping agent tannic acid and the crispness-keeping agent calcium lactate, the crispness and taste of the fresh bamboo shoots are kept in the quick-frozen bamboo shoots, and the application has an outstanding application and promotion prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of food preparation, in particular to a quick-frozen bamboo shoot with preserved crispness and a production process thereof. BACKGROUND

[0002] Bamboo shoots, as the young stems of bamboo plants, have a water content of 90-92% and a crude fiber content of 1.5-2.8%, and are rich in umami amino acids such as aspartic acid and glutamic acid. The unique lattice-like cell arrangement structure makes it have a high natural crispness value. However, this cell wall network composed of pectin-cellulose-hemicellulose is extremely sensitive to temperature changes.

[0003] Bamboo shoots, as a high-dietary fiber and low-calorie specialty vegetable, their fresh and crisp taste is an important food quality index. However, there are the following technical bottlenecks in the quick-freezing process:

[0004] 1. Cell structure damage mechanism: ice crystals produced during freezing can pierce the cell wall, and after thawing, the intercellular water loss leads to the collapse of the tissue structure; 2. Pectin degradation problem: high temperature in traditional fixation process leads to the hydrolysis of original pectin into soluble pectin, losing the intercellular adhesion function; the conventional calcium chloride treatment in existing technology can only maintain the basic crispness, and cannot achieve a crispness recovery rate of more than 90% of fresh bamboo shoots.

[0005] According to the 2024 China Quick-Frozen Vegetable Industry Report, the market size of quick-frozen bamboo shoots has reached 2.36 billion yuan, but the "soft taste" problem accounts for 31.7% of consumer complaints. Market research shows that the crispness retention period of current quick-frozen bamboo shoots products is generally less than 3 months, and the taste score is reduced by more than 40% compared with fresh bamboo shoots. Existing patent technology can extend the crispness retention period to 5 months through composite phosphate treatment, but there is a risk of heavy metal residue; it is urgent to develop a new crispness preservation technology that can stably maintain the cell skeleton structure, so that the crispness of quick-frozen bamboo shoots after thawing is fully preserved, and the crispness and taste of fresh bamboo shoots are achieved, which is of great significance to improve the added value of quick-frozen bamboo shoots products. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, provide a quick-frozen crisp bamboo shoot and its production process, which is first to peel the picked bamboo shoot, then to blanch after peeling, to add treatment agent acetic acid during the blanching process, to blanch the bamboo shoot after blanching, to add crispness agent calcium lactate during the blanching process, to quickly remove the clothes of the bamboo shoot after the blanching is completed, to quickly cool and soak the bamboo shoot after the clothes are removed in the crispness agent tannic acid solution, to pre-cool the bamboo shoot after soaking, and to freeze the bamboo shoot quickly to less than -35℃ on the surface after pre-cooling; complete the preparation of the quick-frozen bamboo shoot, the present application is treated by treatment agent and composite crispness agent, through the synergistic reaction between the crispness agent tannic acid and calcium lactate, the crispness of the quick-frozen bamboo shoot after thawing is fully retained, the crispness and taste of fresh bamboo shoot are retained in the quick-frozen bamboo shoot, and the application has outstanding application and promotion prospects.

[0007] In order to achieve the above technical effects, the following technical solutions are adopted:

[0008] A quick-frozen crisp bamboo shoot production process, comprising the following steps:

[0009] Step (1): picking and selecting bamboo shoot body: picking 10-20 cm long bamboo shoot for peeling; selecting bamboo shoot without insect pests and light yellow color, and transporting it to the treatment point within two hours for blanching and fixation treatment;

[0010] Step (2): blanching: blanching the bamboo shoot in 100℃ boiling water with added acetic acid for 5-10 minutes, the concentration of the acetic acid is 2wt%-3wt%, and the blanching water mass is 2-3 times the mass of the bamboo shoot;

[0011] Step (3): fixation: quickly transferring the blanched bamboo shoot into a pre-boiled fixation pot, the pre-boiled water in the fixation pot contains crispness agent calcium lactate, the concentration of the calcium lactate is 0.5wt%-2wt%, the fixation boiling water mass is 4-5 times the mass of the bamboo shoot, the pressure in the fixation pot is 0.1-0.2 MPa, the fixation time is 10-30 minutes, and the blanched bamboo shoot is quickly removed for clothes removal treatment;

[0012] Step (4): clothes removal treatment: placing the blanched bamboo shoot removed from the pot into a bamboo shoot clothes removal device for clothes removal, and keeping the clothes removed bamboo shoot at 60℃ or above;

[0013] Step (5): cooling and introducing crispness agent tannic acid: introducing the clothes removed bamboo shoot into crispness agent solution for cooling to 20-25℃, soaking for 10-30 minutes, then removing and cutting off the old head, and then washing with circulating clean water for 5-10 minutes; the crispness agent solution is 1wt%-3wt% tannic acid solution, and the temperature is 0-5℃;

[0014] Step (6): pre-cooling: soaking the washed bamboo shoot in ice water for 5-10 minutes to complete the pre-cooling;

[0015] Step (7): packaging: the bamboo shoots after pre-cooling treatment are packaged according to the specification of 0.5-2 kg / bag, and the packaging is carried out in a packaging room at-2℃-2℃;

[0016] Step (8): quick freezing: the packaged bamboo shoots are put into a liquid nitrogen quick freezing tunnel through a conveying belt, and are subjected to quick freezing at a temperature of-80--100℃; the time is 20-30 min out of the tunnel;

[0017] Step (9): cold storage: the quick-frozen bamboo shoots are put into a cold storage room at a temperature of-18℃--20℃ for preservation.

[0018] Further, the bamboo shoots in step (1) are white bamboo shoots, Luohan bamboo shoots, bitter bamboo shoots or bamboo shoots.

[0019] Further, in step (2), the concentration of the acetic acid is 2.5wt%, and the mass of the blanching water is 2 times the mass of the bamboo shoots.

[0020] Further, in step (3), the concentration of the calcium lactate is 1wt%, and the mass of the boiling water for fixation is 4 times the mass of the bamboo shoots.

[0021] Further, in step (3), the pressure in the fixation pot is 0.2 MPa, and the fixation time is 20 min.

[0022] Further, in step (4), the bamboo shoots after the removal of the clothes are kept at 65℃.

[0023] Further, in step (5), the temperature is cooled to 20℃, the soaking time is 20 min, and the circulating water washing time is 5 min.

[0024] Further, in step (5), the brittle-keeping agent solution is a 2wt% tannic acid solution, and the temperature is 2℃.

[0025] A quick-frozen brittle-keeping bamboo shoot is prepared by any one of the preparation methods.

[0026] The beneficial effects of the present application are:

[0027] The application discloses quick-frozen crisp bamboo shoots and a production process thereof, which comprises the following steps: peeling bamboo shoots picked, blanching the peeled bamboo shoots, adding a treating agent acetic acid in the blanching process, fixing the color of the blanched bamboo shoots, adding a crispness-keeping agent calcium lactate in the fixing process, rapidly carrying out a de-clothing treatment on the fixed bamboo shoots, rapidly cooling and soaking the de-clothed bamboo shoots in a crispness-keeping agent tannic acid solution, pre-cooling the soaked bamboo shoots, and quickly freezing the pre-cooled bamboo shoots until the surface temperature of the bamboo shoots is less than -35 DEG C; and the preparation of the quick-frozen bamboo shoots is completed. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application.

[0029] It should be pointed out that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0030] It is to be understood that the terms used herein are for the purpose of describing specific embodiments and are not intended to limit exemplary embodiments according to the present application. As used herein, the singular form is intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, and / or groups thereof, but do not preclude the presence or addition of one or more other features, steps, operations, elements, and / or groups thereof.

[0031] Embodiment 1

[0032] The present embodiment relates to a quick-frozen crispy bamboo shoot and a production process thereof.

[0033] Step (1): picking and selecting of bamboo shoots: picking 10-20 cm long bamboo shoots and removing the shell; selecting bamboo shoots without insect damage and light yellow color, and transporting them to the treatment point within two hours for blanching and fixation treatment; the bamboo shoots are white bamboo shoots.

[0034] Step (2): blanching: placing the bamboo shoots in 100℃ boiling water with added acetic acid for 5 minutes, the concentration of the acetic acid being 2wt%; the blanching water mass being 2 times the mass of the bamboo shoots;

[0035] Step (3): fixation: quickly transferring the blanched bamboo shoots to a pre-boiled fixation pot, the pre-boiled water in the fixation pot containing crispy agent calcium lactate, the concentration of the calcium lactate being 0.5wt%; the fixation boiling water mass being 4 times the mass of the bamboo shoots; the pressure in the fixation pot being 0.1 MPa, and the fixation time being 10 minutes; after fixation, quickly taking out for dehulling treatment;

[0036] Step (4): dehulling treatment: placing the taken-out bamboo shoots after fixation in a bamboo shoot dehulling device for dehulling, and keeping the dehulled bamboo shoots at 60℃;

[0037] Step (5): cooling and introducing crispy agent tannic acid: introducing the dehulled bamboo shoots into a crispy agent solution to cool to 20℃, soaking for 10 minutes, then taking out and cutting off the old head, and then washing with circulating clean water for 5 minutes; the crispy agent solution is a 1wt% tannic acid solution with a temperature of 0℃;

[0038] Step (6): pre-cooling: immersing the washed bamboo shoots in ice water for 5 minutes to complete pre-cooling;

[0039] Step (7): packaging: packaging the pre-cooled bamboo shoots according to the specification of 0.5-2 kg / bag in a packaging room at -2℃-2℃;

[0040] Step (8): quick freezing: introducing the packaged bamboo shoots into a liquid nitrogen quick-freezing tunnel through a conveying belt for quick freezing at a temperature of -80 for 20 minutes to exit the tunnel;

[0041] Step (9): Cold storage: The quick-frozen bamboo shoots are put into a cold storage room with a temperature of -18°C for preservation.

[0042] The quick-frozen bamboo shoots 1 described in Example 1 are obtained.

[0043] Example 2:

[0044] This example relates to a quick-frozen bamboo shoot with preserved crispness and a production process thereof:

[0045] Step (1): Harvesting and selecting bamboo shoots: Bamboo shoots with a length of 10-20 cm are harvested and peeled; bamboo shoots without insect damage and with light yellow color are selected and transported to a treatment point within two hours for blanching and fixation treatment; the bamboo shoots are Phyllostachys nidularis bamboo shoots.

[0046] Step (2): Blanching: The bamboo shoots are blanched in 100°C boiling water with added acetic acid for 10 minutes, the concentration of the acetic acid being 3wt%; the blanching water mass is 3 times the mass of the bamboo shoots;

[0047] Step (3): Fixation: The blanched bamboo shoots are quickly transferred to a pre-boiled fixation pot, the pre-boiled water in the fixation pot containing calcium lactate as a crispness preservation agent, the concentration of the calcium lactate being 2wt%; the fixation boiling water mass is 5 times the mass of the bamboo shoots; the pressure in the fixation pot is 0.2MPa, and the fixation time is 30 minutes; after fixation, the bamboo shoots are quickly fished out for dehulling treatment;

[0048] Step (4): Dehulling treatment: The fished-out bamboo shoots after fixation are placed in a bamboo shoot dehulling device for dehulling, and the dehulled bamboo shoots are kept at 65°C;

[0049] Step (5): Cooling and introducing crispness preservation agent tannic acid: The dehulled bamboo shoots are introduced into a crispness preservation agent solution for cooling to 25°C, soaked for 30 minutes, then fished out and cut off the old head, and then rinsed with circulating clean water for 10 minutes; the crispness preservation agent solution is a 3wt% tannic acid solution with a temperature of 5°C;

[0050] Step (6): Pre-cooling: The rinsed bamboo shoots are immersed in ice water for 10 minutes to complete pre-cooling;

[0051] Step (7): Packaging: The bamboo shoots after pre-cooling treatment are packaged according to a specification of 0.5-2kg / bag, and the packaging is carried out in a packaging room with a temperature of -2°C-2°C;

[0052] Step (8): Quick-freezing: The packaged bamboo shoots are introduced into a liquid nitrogen quick-freezing tunnel through a conveying belt for quick-freezing, the temperature being -100°C; the time being 30 minutes to exit the tunnel;

[0053] Step (9): Cold storage: The quick-frozen bamboo shoots are put into a cold storage room with a temperature of -20°C for preservation.

[0054] Obtaining the quick-frozen bamboo shoots 2 described in Example 2.

[0055] Example 3:

[0056] This example relates to a quick-frozen bamboo shoot with crispness preservation and a production process thereof:

[0057] Step (1): picking and selecting of bamboo shoots: picking bamboo shoots of 10-20 cm long and removing the shell; selecting bamboo shoots without insect damage and light yellow color, and transporting them to the treatment point within two hours for blanching and fixation treatment; the bamboo shoots are Luohan bamboo shoots.

[0058] Step (2): blanching: placing the bamboo shoots in 100°C boiling water with added acetic acid for 8 minutes, the concentration of the acetic acid being 2.5wt%; the blanching water mass being 2 times the mass of the bamboo shoots;

[0059] Step (3): fixation: quickly transferring the blanched bamboo shoots to a pre-boiled fixation pot, the pre-boiled water in the fixation pot containing crispness preservation agent calcium lactate, the concentration of the calcium lactate being 1wt%; the fixation boiling water mass being 4 times the mass of the bamboo shoots; the pressure in the fixation pot being 0.2MPa, and the fixation time being 20 minutes; after fixation, quickly taking out for dehulling treatment;

[0060] Step (4): dehulling treatment: placing the taken-out bamboo shoots after fixation in a bamboo shoot dehulling device for dehulling, and keeping the dehulled bamboo shoots at 65°C;

[0061] Step (5): cooling and introducing crispness preservation agent tannic acid: introducing the dehulled bamboo shoots into a crispness preservation agent solution to cool to 20°C, soaking for 20 minutes, then taking out and cutting off the old head, and then washing with circulating clean water for 5min; the crispness preservation agent solution is a 2wt% tannic acid solution with a temperature of 2°C;

[0062] Step (6): pre-cooling: immersing the washed bamboo shoots in ice water for 10min to complete pre-cooling;

[0063] Step (7): packaging: packaging the pre-cooled bamboo shoots according to the specification of 0.5-2kg / bag, and packaging in a packaging room at -2°C-2°C;

[0064] Step (8): quick-freezing: introducing the packaged bamboo shoots into a liquid nitrogen quick-freezing tunnel through a conveying belt for quick-freezing, the temperature being -80°C; the time being 25min to exit the tunnel;

[0065] Step (9): cold storage: placing the quick-frozen bamboo shoots in a cold storage room with a temperature of -20°C for preservation.

[0066] Obtaining the quick-frozen bamboo shoots 3 described in Example 3.

[0067] Comparative Example 1:

[0068] The comparative example 1 relates to a quick-frozen bamboo shoot with crispness-keeping and a production process thereof, and is based on the example 3 without adding two crispness-keeping agents:

[0069] Step (1): picking and selecting of bamboo shoots: picking bamboo shoots with a length of 10-20 cm and removing the sheath; selecting bamboo shoots without insect pests and with light yellow color, and transporting the bamboo shoots to a treatment point within two hours for blanching and fixation treatment; the bamboo shoots are Luohan bamboo shoots.

[0070] Step (2): blanching: placing the bamboo shoots in boiling water at 100°C with added acetic acid for 8 minutes, the concentration of the acetic acid being 2.5 wt%; the mass of the blanching water being 2 times the mass of the bamboo shoots;

[0071] Step (3): fixation: quickly transferring the blanched bamboo shoots to a pre-boiled fixation kettle, the pre-boiled water in the fixation kettle not containing the crispness-keeping agent calcium lactate (concentration being 0 wt%), the mass of the fixation boiling water being 4 times the mass of the bamboo shoots; the pressure in the fixation kettle being 0.2 MPa, and the fixation time being 20 minutes; after fixation, quickly taking out the bamboo shoots for peeling treatment;

[0072] Step (4): peeling treatment: placing the fixed bamboo shoots taken out after fixation in a bamboo shoot peeling device for peeling, and keeping the peeled bamboo shoots at 65°C;

[0073] Step (5): cooling: guiding the peeled bamboo shoots into clean water to cool to 20°C, soaking for 20 minutes, then taking out and cutting off the old head, and then washing with circulating clean water for 5 min; the temperature of the clean water being 2°C;

[0074] Step (6): pre-cooling: immersing the washed bamboo shoots in ice water for 10 min to complete pre-cooling;

[0075] Step (7): packaging: packaging the bamboo shoots after pre-cooling according to a specification of 0.5-2 kg / bag, and packaging in a packaging room at -2°C-2°C;

[0076] Step (8): quick freezing: guiding the packaged bamboo shoots into a liquid nitrogen quick-freezing tunnel through a conveying belt to perform quick freezing at a temperature of -80°C; the time being 25 min to exit the tunnel;

[0077] Step (9): cold storage: placing the quick-frozen bamboo shoots into a cold storage room at a temperature of -20°C for preservation.

[0078] The quick-frozen bamboo shoots 4 of the comparative example 1 are obtained.

[0079] Comparative example 2:

[0080] The example 3 relates to a quick-frozen bamboo shoot with crispness-keeping and a production process thereof, and is based on the example 1, only adding the crispness-keeping agent calcium lactate:

[0081] Step (1): picking and selection of bamboo shoots: picking 10-20 cm long bamboo shoots and removing the shell; selecting bamboo shoots without insect damage and light yellow color, and transporting them to the treatment point within two hours for blanching and fixation treatment; the bamboo shoots are Luohan bamboo shoots.

[0082] Step (2): blanching: blanching the bamboo shoots in 100°C boiling water with 2.5wt% acetic acid for 8 minutes; the blanching water mass is 2 times the mass of the bamboo shoots;

[0083] Step (3): fixation: quickly transferring the blanched bamboo shoots to a pre-boiled fixation pot, and the pre-boiled water in the fixation pot contains 1wt% calcium lactate as a crispness preserving agent; the fixation boiling water mass is 4 times the mass of the bamboo shoots; the pressure in the fixation pot is 0.2MPa, and the fixation time is 20 minutes; after fixation, the bamboo shoots are quickly removed for peeling treatment;

[0084] Step (4): peeling treatment: placing the removed bamboo shoots after fixation in a bamboo shoot peeling device for peeling, and the peeled bamboo shoots are kept at 65°C;

[0085] Step (5): cooling: cooling the peeled bamboo shoots in clean water to 20°C for 20 minutes, then removing and cutting off the old head, and then washing with circulating clean water for 5 minutes; the clean water temperature is 2°C;

[0086] Step (6): pre-cooling: immersing the washed bamboo shoots in ice water for 10 minutes to complete pre-cooling;

[0087] Step (7): packaging: packaging the pre-cooled bamboo shoots according to the specification of 0.5-2kg / bag in a packaging room at -2°C-2°C;

[0088] Step (8): quick freezing: placing the packaged bamboo shoots into a liquid nitrogen quick freezing tunnel through a conveying belt for quick freezing at a temperature of -80°C; the time is 25 minutes to exit the tunnel;

[0089] Step (9): cold storage: placing the quick-frozen bamboo shoots in a cold storage room at a temperature of -20°C for preservation.

[0090] The quick-frozen bamboo shoots 5 of Comparative Example 2 are obtained.

[0091] Comparative Example 3:

[0092] This example relates to a kind of quick-frozen crisp bamboo shoots and its production process: taking example 3 as a benchmark, only adding crispness preserving agent tannic acid:

[0093] Step (1): picking and selection of bamboo shoots: picking 10-20 cm long bamboo shoots and removing the shell; selecting bamboo shoots without insect damage and light yellow color, and transporting them to the treatment point within two hours for blanching and fixation treatment; the bamboo shoots are Luohan bamboo shoots.

[0094] Step (2): Blanching: the bamboo shoots were placed in 100℃ boiling water with 2.5wt% acetic acid for 8 minutes; the blanching water was 2 times the mass of the bamboo shoots;

[0095] Step (3): Fixation: the blanched bamboo shoots were quickly transferred to a pre-boiled fixation pot, the pre-boiled water in the fixation pot did not contain calcium lactate (0wt%) as a crispness preserving agent, the fixation boiling water was 4 times the mass of the bamboo shoots; the pressure in the fixation pot was 0.2MPa, the fixation time was 20 minutes; after fixation, the bamboo shoots were quickly removed for dehulling treatment;

[0096] Step (4): Dehulling treatment: the removed bamboo shoots were placed in a bamboo shoot dehulling device for dehulling, the dehulled bamboo shoots were kept at 65℃;

[0097] Step (5): Cooling and introducing crispness preserving agent tannic acid: the dehulled bamboo shoots were introduced into a crispness preserving agent solution and cooled to 20℃, soaked for 20 minutes, then removed and cut off the old head, and then washed with circulating water for 5min; the crispness preserving agent solution was a 2wt% tannic acid solution with a temperature of 2℃;

[0098] Step (6): Pre-cooling: the washed bamboo shoots were immersed in ice water for 10min to complete pre-cooling;

[0099] Step (7): Packaging: the pre-cooled bamboo shoots were packaged according to the specifications of 0.5-2kg / bag, and the packaging was carried out in a packaging room at -2℃-2℃;

[0100] Step (8): Quick freezing: the packaged bamboo shoots were introduced into a liquid nitrogen quick freezing tunnel through a conveying belt for quick freezing at a temperature of -80℃; the time was 25min to exit the tunnel;

[0101] Step (9): Cold storage: the quick frozen bamboo shoots were placed in a cold storage room at a temperature of -20℃ for preservation.

[0102] The quick frozen bamboo shoots 6 of Comparative Example 3 were obtained.

[0103] The quick frozen bamboo shoots in Examples 1-3 and Comparative Examples 1-3 were tested for crispness, first the quick frozen bamboo shoots in Examples 1-3 and Comparative Examples 1-3 were completely thawed and then immediately tested for crispness, a texture analyzer (Brookfield CT3, USA) was used to test the breaking force of the thawed bamboo shoots, TPA Test mode, and the crispness parameters were exported using TexturePro CT software; a clamp was used during the test to prevent the bamboo shoots from sliding sideways, the same position was selected for testing (bamboo shoot slice thickness 10mm), 20 samples were tested for each example or comparative example, and the average value was taken, the results are shown in Table 1:

[0104] Table 1 Comparison of brittleness of quick-frozen bamboo shoots prepared in Examples 1-3 and Comparative Examples 1-3 after thawing

[0105]

[0106] Therefore, in summary, the application discloses a kind of quick-frozen bamboo shoots and its production process, the process is first after picking bamboo shoots shell, shell is boiled, add treatment agent acetic acid in boiling process, bamboo shoots after boiling are blanched, add brittleness agent calcium lactate in blanching process, the bamboo shoots after blanching are quickly handled with clothes, the bamboo shoots after taking off clothes are quickly cooled and soaked with brittleness agent tannic acid solution, bamboo shoots after soaking are pre-cooled, and are quickly frozen to bamboo shoots surface temperature less than-35 ℃ after pre-cooling;Complete quick-frozen bamboo shoots preparation, the application is treated by treatment agent and composite brittleness agent, after treatment agent acetic acid enters the bamboo shoots, effectively prevent the dissociation of carboxyl on pectin, the hydration of pectin is reduced, which is conducive to the combination of pectin and the formation of three-dimensional network structure, laying the foundation for the combination of subsequent brittleness agent, in the blanching process, after calcium ions enter the bamboo shoots, pectin acid can be combined with calcium ions to form insoluble pectin acid salt, this salt forms a rigid support structure by filling the intercellular space, enhances the tissue firmness, so that bamboo shoots remain brittle, after taking off clothes, the bamboo shoots are cooled with brittleness agent tannic acid solution, the temperature of brittleness agent tannic acid solution is relatively low, the temperature of the bamboo shoots just after taking off clothes is above 60 ℃, thermal expansion and cold contraction, after the bamboo shoots contact with brittleness agent tannic acid solution, tannic acid in brittleness agent solution quickly enters the bamboo shoots, complexation reaction occurs between tannic acid phenolic hydroxyl in the bamboo shoots and calcium ions, to generate stable elastic gel material, directly enhance the intercellular adhesion strength, the phenolic hydroxyl in tannic acid can also combine with cellulose on the cell wall and alcohol hydroxyl in pectin through hydrogen bond interaction to form a crosslinked network, significantly improve the mechanical strength of cell wall;The brittleness of quick-frozen bamboo shoots product is improved by the above-mentioned synergistic reaction, the support material strength between cells is greatly improved, the brittleness of quick-frozen bamboo shoots is significantly improved, and the taste is comparable to fresh bamboo shoots. And due to the sharp change in temperature, the bamboo shoots surface tightens, locks the brittleness agent tannic acid and calcium lactate in the bamboo shoots, the brittleness agent plays a greater effect, and the bamboo shoots have better brittleness effect. It has outstanding application and promotion prospects.

[0107] At this point, those skilled in the art realize that, although the embodiments of the application have been fully demonstrated and described herein, many other variations or modifications in accordance with the principles of the application can be directly determined or deduced from the disclosure of the application without departing from the spirit and scope of the application. Therefore, the scope of the application should be understood and recognized as covering all these other variations or modifications.

Claims

1. A process for the production of quick-frozen and crispy bamboo shoot, characterized in that, The production process comprises the following steps: Step (1): picking and selecting bamboo shoots: picking 10-20 cm long bamboo shoots and removing the shell; selecting bamboo shoots without insect pests and with light yellow color, and transporting them to a treatment point within two hours for blanching and fixation treatment; Step (2): blanching: placing the bamboo shoots into 100℃ boiling water added with acetic acid for blanching for 5-10 minutes, wherein the concentration of the acetic acid is 2wt%-3wt%, and the mass of the blanching boiling water is 2-3 times the mass of the bamboo shoots; Step (3): fixation: quickly transferring the blanched bamboo shoots into a pre-boiled fixation kettle, wherein the pre-boiled boiling water in the fixation kettle contains calcium lactate as a crispness preserving agent, the concentration of the calcium lactate is 0.5wt%-2wt%, the mass of the fixation boiling water is 4-5 times the mass of the bamboo shoots, the pressure in the fixation kettle is 0.1-0.2 MPa, and the fixation time is 10-30 minutes; and quickly taking out the bamboo shoots after fixation for peeling treatment; Step (4): peeling treatment: placing the bamboo shoots taken out after fixation into a bamboo shoot peeling device for peeling, and keeping the peeled bamboo shoots at 60℃ or above; Step (5): cooling and introducing crispness preserving agent tannic acid: introducing the peeled bamboo shoots into a crispness preserving agent solution for cooling to 20-25℃, soaking for 10-30 minutes, then taking out and cutting off the old head, and then washing with circulating clean water for 5-10 minutes; the crispness preserving agent solution is a 1wt%-2wt% tannic acid solution with a temperature of 0-5℃; Step (6): precooling: immersing the washed bamboo shoots into ice water for 5-10 minutes to complete precooling; Step (7): packaging: packaging the bamboo shoots after precooling according to a specification of 0.5-2 kg / bag, and packaging in a packaging room at a temperature of -2℃-2℃; Step (8): quick freezing: introducing the packaged bamboo shoots into a liquid nitrogen quick freezing tunnel through a conveying belt for quick freezing at a temperature of -80--100℃ for 20-30 minutes; Step (9): cold storage: placing the quick frozen bamboo shoots into a cold storage room at a temperature of -18℃--20℃ for preservation. The bamboo shoots in step (1) are white bamboo shoots, Luohan bamboo shoots, bitter bamboo shoots or bamboo shoots.

2. The process for producing quick-frozen and crispy bamboo shoot according to claim 1, wherein In step (2), the blanching is performed for 8 minutes, and the concentration of the acetic acid is 2.5wt%; and the mass of the blanching boiling water is 2 times the mass of the bamboo shoots.

3. The process for producing quick-frozen and crispy bamboo shoot according to claim 1, wherein In step (3), the concentration of the calcium lactate is 1wt%, and the mass of the fixation boiling water is 4 times the mass of the bamboo shoots.

4. The process for producing quick-frozen and crispy bamboo shoot according to claim 1, wherein In step (3), the pressure in the fixation kettle is 0.2 MPa, and the fixation time is 20 minutes.

5. The process for producing quick-frozen and crispy bamboo shoot according to claim 1, wherein In step (4), the peeled bamboo shoots are kept at 65℃.

6. The process for quick-frozen and crispy bamboo shoot production as claimed in claim 1, characterized in that, In step (5), the temperature is cooled to 20℃, the soaking time is 20 minutes, and the circulating clean water washing time is 5 minutes.

7. The process for quick-frozen and crispy bamboo shoot production as claimed in claim 1, characterized in that, In step (5), the temperature of the crispness preserving agent solution is 2℃.

8. The process for producing quick-frozen and crispy bamboo shoot according to claim 1, wherein The quick frozen crisp bamboo shoots are produced by the production process in any one of claims 1-8.

9. A quick-frozen and crispy bamboo shoot, characterized in that, ​

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