Method for frying cherry tomatoes treated by peeling process

Abstract

The invention relates to the technical field of food processing, in particular to a method for frying cherry tomatoes treated by a peeling process. The method comprises the following steps: S1, raw material treatment: removing pedicles on cherry tomatoes; s2, performing peeling treatment: performing treatment on the cleaned cherry tomatoes; s3, performing fixation treatment: performing heat treatment on the cherry tomatoes subjected to the peeling treatment, and performing auxiliary peeling at the same time; s4, water removal: removing excessive water through draining or dewatering to improve the dipping efficiency; s5, soaking: soaking the dehydrated cherry tomatoes in a soaking solution; s6, draining: draining the soaked cherry tomatoes through a fan of a conveying belt; s7, quick-freezing: putting the drained cherry tomatoes into a quick-freezing machine for quick-freezing treatment; s8, performing low-temperature vacuum frying; according to the present invention, the frying solution of the cherry tomato raw material with skin and high internal moisture content is provided, the peeling rate and the yield of the product can be effectively improved by using the method, and the frying quality of the cherry tomato is improved.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to a method for frying small tomatoes that have been processed by a peeling process. Background Art

[0002] Fried fruit and vegetable products refer to fruit and vegetable products that have been processed by frying. This processing technology usually gives fruits and vegetables a crispier taste and can extend their shelf life. During the frying process, the moisture content of fruits and vegetables will decrease, thereby improving their convenience in storage and carrying. Due to their unique taste and convenience, fried fruit and vegetable products are still favored by many consumers.

[0003] At present, most of the fried fruit and vegetable products on the market are varieties with low moisture content. Common fried fruit and vegetable products include fried banana chips, potato chips, sweet potato chips, onion rings, etc. During the frying process of these fruits and vegetables with low moisture content, the evaporation of water and the penetration of oil can reach a balance, so that the final fried products have an attractive taste and can maintain the nutritional value of fruits and vegetables to a certain extent. These products after frying can maintain a good taste and a long shelf life. Due to the low moisture content, these fruits and vegetables are not easy to absorb too much oil during the frying process, so that the finished product has a crispy texture and rich flavor.

[0004] However, for those fruit and vegetable raw materials with skin and high internal moisture content, such as cherry tomatoes, their high moisture characteristics are prone to bursting during frying, which not only affects the appearance and taste of the product, but also may bring safety risks. Therefore, for such fruit and vegetable raw materials with high moisture content, researching and developing appropriate frying technology and equipment to ensure product quality and safety is a topic worthy of in-depth discussion and research. Summary of the invention

[0005] In view of the shortcomings of the existing technology, the present invention proposes a method for frying cherry tomatoes that have been processed by a peeling process, with the aim of providing a solution to frying raw materials such as cherry tomatoes with skin and high internal moisture content. The method can effectively improve the peeling rate and yield rate of the product, and improve the frying quality of cherry tomatoes.

[0006] To achieve the above object, the present invention adopts the following technical scheme: a method for frying small tomatoes after peeling, characterized in that it comprises at least the following steps:

[0007] S1. Raw material processing: removing the stems of the cherry tomatoes to facilitate the subsequent peeling process; placing the cherry tomatoes after the stems are removed into a washing machine for washing to ensure the surface is clean;

[0008] S2, peeling treatment: treating the washed cherry tomatoes to change the temperature on their surface, thereby promoting the separation between the peel and the flesh;

[0009] S3, withering treatment: the peeled tomatoes need to be heat treated and assisted with peeling to ensure that the peel can be completely removed and the flesh is broken;

[0010] S4. Dehydration: Remove excess water by draining or dehydrating to improve the impregnation efficiency;

[0011] S5, soaking: soaking the dehydrated cherry tomatoes in the soaking liquid. This step helps to form a color protection effect and ensures that the cherry tomatoes maintain their bright color;

[0012] S6, draining: the soaked tomatoes are drained by the fan on the conveyor belt, and the fan blows away the excess water on the surface, which is conducive to the subsequent quick freezing;

[0013] S7, quick freezing: the drained tomatoes are put into a quick freezing machine for quick freezing, so that the water in the tomatoes is converted from liquid to solid to maintain their freshness and taste;

[0014] S8. Low-temperature vacuum frying: Finally, the processed cherry tomatoes are placed in an oil bath for low-temperature vacuum oil bath treatment to give the finished product a crispy taste.

[0015] Further, the washed cherry tomatoes are peeled by any of the following three different methods:

[0016] The first method: step S2-1, steam heating: heating the washed cherry tomatoes by steam heating to increase the surface temperature thereof, thereby promoting the separation between the peel and the flesh;

[0017] The parameters of the steam equipment configuration are: feed rate 1.5-3.5t / h, peeling time 3-8s, steam temperature 85-100℃; or

[0018] The parameters of the steam equipment configuration are: feed rate 3t / h, peeling time 4s, steam temperature 98℃;

[0019] The second method: step S2-2, steam heating combined with piercing: the washed cherry tomatoes are heated by steam heating, and then conveyed to the piercing device by a conveyor belt for piercing the cherry tomatoes, so that the surface temperature is increased and the surface pores are increased, thereby promoting the separation between the peel and the flesh;

[0020] Steam parameters: feed rate 1.5-3.5t / h, peeling time 3-8s, steam temperature 85-100℃;

[0021] Punching parameters: frequency 15-25Hz, which is the frequency at which the punching equipment descends to punch holes; or

[0022] The third method: Step S2-3, quick freezing combined with steam heating: The washed cherry tomatoes are quick-frozen by a quick-freezing machine, and then peeled by steam heating, so as to promote the separation between the peel and the flesh through the changes of thermal expansion and contraction.

[0023] Further, the fixing process is carried out in any of the following ways:

[0024] The first method: Step S3-1, blanching: blanching the peeled tomatoes with hot water to break the tomatoes and optimize the taste of the flesh; the blanching temperature is 95-100° C. and the blanching time is 40-360 seconds; or

[0025] The second method: step S3-2, steaming: steaming the peeled tomatoes by heating with steam to de-cook the tomatoes, reduce the moisture, and promote the maceration of the pulp;

[0026] Further, the water removal treatment adopts any of the following methods:

[0027] The first method: step S4-1, water control: drying the surface moisture by hot air drying with a fan, this step helps to remove excess moisture on the surface of the small red, and improves the efficiency of the immersion; or

[0028] The second method: Step S4-2, dehydration: the soaked cherry tomatoes are placed in a dehydrator for dehydration. This step helps to remove excess water from the cherry tomatoes and improves the efficiency of soaking.

[0029] Further, the formula of the impregnation liquid is any one of the following:

[0030] Soaking formula 1: maltodextrin 15-35%, edible salt 1.5-2.5%, maltose syrup 15-55%;

[0031] Dipping formula 2: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, maltose syrup 15-55%;

[0032] Soaking formula 3: maltodextrin 15-35%, edible salt 1.5-2.5%, white sugar 15-35%;

[0033] Dipping formula 4: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, white sugar 15-35%; or

[0034] Dipping formula 5: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, white sugar 15-35%, citric acid 0.5-2%;

[0035] Among them, the type of curing agent in the impregnation formula 1 or the impregnation formula 2 or the impregnation formula 4 or the impregnation formula 5 is any one of calcium chloride, calcium hydroxide or calcium lactate.

[0036] Further, step S5-1, normal pressure immersion: soaking the withered cherry tomatoes in a sugar solution of a certain concentration under normal pressure to ensure the taste and color of the cherry tomatoes;

[0037] Dipping process: Mix 1 times of cherry tomatoes with 1-2 times of dipping solution and soak at a temperature of 15-60°C for 3-12 hours. The dipping solution is prepared according to formula S5.

[0038] Further, step S5-2, vacuum impregnation: under vacuum conditions, the withered cherry tomatoes are soaked in a sugar solution of a certain concentration to ensure the taste and color of the cherry tomatoes;

[0039] Dipping process: Mix 1 times of cherry tomatoes with 0.5-1.5 times of dipping liquid in a vacuum tumbling machine with a vacuum pressure of 0.05-0.09 MPa and a vacuum time of 20-120 min.

[0040] Further, step S5-3, differential pressure immersion: under the condition of continuous circulation of true pressure-normal pressure, the withered cherry tomatoes are immersed in a sugar solution of a certain concentration to ensure the taste and color of the cherry tomatoes;

[0041] Dipping process: Mix 1 times the amount of cherry tomatoes with 0.5-1.5 times the amount of dipping liquid in a vacuum rolling machine, and perform vacuum and normal pressure cycle dipping. First, evacuate the air to a vacuum degree of 0.05-0.09MPa, roll and knead at pressure for 5-20 minutes, then release the air and release the pressure, roll and knead at normal pressure for 5-10 minutes, and repeat the cycle in sequence. The dipping time is 0.5-2h.

[0042] Further, in step S8, a low-temperature vacuum oil bath is performed in the oil bath pot, wherein the frying parameters are: vacuum degree 0.05-0.1MPa, frying temperature 90-120°C, frying time 120-200min, de-oiling speed 150-300R, and de-oiling time 3-10min. Or

[0043] In step S8, a low-temperature vacuum oil bath treatment is performed in the oil bath pot, wherein the frying parameters are: vacuum degree 0.05-0.1 MPa, frying temperature 98° C., frying time 186 min, deoiling speed 200R, and deoiling time 8 min.

[0044] Furthermore, after the peeling process in step S2 and before the withering process in step S3, a plurality of puncture points are formed on the cherry tomatoes using a piercing device to increase the number of holes on the tomato skin and their distribution range, thereby promoting the peeling process;

[0045] The piercing device at least includes a conveyor belt, parallel baffles, a piercing mechanism and a plurality of needles; wherein

[0046] The small tomatoes are transported by a conveyor belt and arranged into a neat queue with the help of a parallel baffle. A piercing mechanism is provided at the end of the parallel baffle. When the small tomatoes arrive at this position, the piercing mechanism drives the row needles to perform up and down reciprocating motion. The row needles are clustered needle structures and can form multiple puncture points at one time to perform piercing operations on the small tomatoes.

[0047] The present invention adopts the above technical solution, which has at least the following beneficial effects:

[0048] 1. Process innovation

[0049] The invention fills the technological gap and provides a new frying process for raw materials with skin and high water content such as cherry tomatoes. In the prior art, there are few frying processes for such fruits and vegetables with high water content. The invention provides a new technological idea and method in this field and expands the range of fried fruit and vegetable products.

[0050] For example, in the past, frying technology focused on fruits and vegetables with low moisture content. The emergence of this technology allows high-moisture fruits and vegetables such as cherry tomatoes to be fried through reasonable process design, providing possibilities for the diversified development of products in the fruit and vegetable processing industry.

[0051] The process steps are synergistic and closely coordinated to form a complete processing flow. Manual pedunculation lays the foundation for subsequent peeling, washing ensures the cleanliness of the raw materials, steam peeling initially separates the peel and pulp, piercing combined with subsequent blanching and manual assisted peeling further improves the peeling effect, immersion plays a role in color protection, and quick freezing and low-temperature vacuum frying optimize the finished product in terms of physical state and taste respectively.

[0052] This synergistic effect makes the processing of cherry tomatoes from raw materials to finished products more scientific and reasonable, and improves the overall quality of the product, such as color, taste, etc.

[0053] 2. Product quality improvement

[0054] Improve the taste and color of the product. The low-temperature vacuum frying process makes the finished product have a crispy taste, which is difficult to achieve with ordinary frying methods. This unique taste can attract more consumers and increase the market acceptance of the product.

[0055] The sugar liquid dipping step protects the color of the product, allowing the fried cherry tomatoes to maintain a good color, making the appearance more attractive and visually appealing to consumers. At the same time, it also retains the nutritional components of the cherry tomatoes to a certain extent, thereby improving the nutritional value of the product.

[0056] 3. Production efficiency and economic benefits

[0057] Improving the yield rate brings economic benefits. A higher peeling rate and the optimization of the overall processing technology improve the yield rate of the product, that is, more qualified finished products can be obtained from a certain amount of raw materials. This directly increases the output of the product and improves the economic benefits of the enterprise while keeping the raw material cost unchanged.

[0058] IV. Environmental protection and sustainable development

[0059] Reduce the waste of raw materials. By improving the peeling rate and yield rate, the waste of cherry tomatoes caused by incomplete peeling during processing is reduced. This is in line with the concept of environmental protection and sustainable development and improves resource utilization.

[0060] In the long run, reducing raw material waste will help reduce the company's raw material procurement costs, while also contributing to environmental protection and reducing waste generation.

[0061] The environmental advantage of low-temperature vacuum frying is that compared with traditional frying, low-temperature vacuum frying is carried out at a lower temperature and in a vacuum environment, which reduces oil oxidation and the generation of harmful substances. This is not only beneficial to consumer health, but also reduces environmental pollution during the frying process, such as oil fume emissions.

[0062] This process meets the environmental protection and health requirements of modern food processing, making the product more sustainable in the market, which is conducive to the company establishing a good social image and enhancing its market competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0064] Figure 1 The present invention is a flowchart of a method for frying small tomatoes. DETAILED DESCRIPTION

[0065] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0066] Embodiment 1

[0067] like Figure 1 As shown, this embodiment provides a method for frying small tomatoes after peeling, which is characterized by at least comprising the following steps:

[0068] S1. Raw material processing: removing the stems of the cherry tomatoes to facilitate the subsequent peeling process; placing the cherry tomatoes after the stems are removed into a washing machine for washing to ensure the surface is clean;

[0069] S2, peeling treatment: treating the washed cherry tomatoes to change the temperature on their surface, thereby promoting the separation between the peel and the flesh;

[0070] S3, withering treatment: the peeled tomatoes need to be heat treated and assisted with peeling to ensure that the peel can be completely removed and the flesh is broken;

[0071] S4. Dehydration: Remove excess water by draining or dehydrating to improve the impregnation efficiency;

[0072] S5, soaking: soaking the dehydrated cherry tomatoes in the soaking liquid. This step helps to form a color protection effect and ensures that the cherry tomatoes maintain their bright color;

[0073] S6, draining: the soaked tomatoes are drained by the fan on the conveyor belt, and the fan blows away the excess water on the surface, which is conducive to the subsequent quick freezing;

[0074] S7, quick freezing: the drained tomatoes are put into a quick freezing machine for quick freezing, so that the water in the tomatoes is converted from liquid to solid to maintain their freshness and taste;

[0075] S8. Low-temperature vacuum frying: Finally, the processed cherry tomatoes are placed in an oil bath for low-temperature vacuum oil bath treatment to give the finished product a crispy taste.

[0076] Embodiment 2

[0077] This embodiment provides a method for frying small tomatoes after peeling, which is characterized by comprising at least the following steps:

[0078] S1. Raw material processing: removing the stems of the cherry tomatoes to facilitate the subsequent peeling process; placing the cherry tomatoes after the stems are removed into a washing machine for washing to ensure the surface is clean;

[0079] S2, peeling treatment: treating the washed cherry tomatoes to change the temperature on their surface, thereby promoting the separation between the peel and the flesh;

[0080] As a preferred embodiment, in this embodiment, the washed cherry tomatoes are peeled in any of the following three different ways:

[0081] The first method: step S2-1, steam heating: heating the washed cherry tomatoes by steam heating to increase the surface temperature thereof, thereby promoting the separation between the peel and the flesh;

[0082] The parameters of the steam equipment configuration are: feed rate 1.5-3.5t / h, peeling time 3-8s, steam temperature 85-100℃; or

[0083] The parameters of the steam equipment configuration are: feed rate 3t / h, peeling time 4s, steam temperature 98℃;

[0084] The second method: step S2-2, steam heating combined with piercing: the washed cherry tomatoes are heated by steam heating, and then conveyed to the piercing device by a conveyor belt for piercing the cherry tomatoes, so that the surface temperature is increased and the surface pores are increased, thereby promoting the separation between the peel and the flesh;

[0085] Steam parameters: feed rate 1.5-3.5t / h, peeling time 3-8s, steam temperature 85-100℃;

[0086] Punching parameters: frequency 15-25Hz, which is the frequency at which the punching equipment descends to punch holes; or

[0087] The third method: Step S2-3, quick freezing combined with steam heating: The washed cherry tomatoes are quick-frozen by a quick-freezing machine, and then peeled by steam heating, so as to promote the separation between the peel and the flesh through the changes of thermal expansion and contraction.

[0088] S3, withering treatment: the peeled tomatoes need to be heat treated and assisted with peeling to ensure that the peel can be completely removed and the flesh is broken;

[0089] S4. Dehydration: Remove excess water by draining or dehydrating to improve the impregnation efficiency;

[0090] S5, soaking: soaking the dehydrated cherry tomatoes in the soaking liquid. This step helps to form a color protection effect and ensures that the cherry tomatoes maintain their bright color;

[0091] S6, draining: the soaked tomatoes are drained by the fan on the conveyor belt, and the fan blows away the excess water on the surface, which is conducive to the subsequent quick freezing;

[0092] S7, quick freezing: the drained tomatoes are put into a quick freezing machine for quick freezing, so that the water in the tomatoes is converted from liquid to solid to maintain their freshness and taste;

[0093] S8. Low-temperature vacuum frying: Finally, the processed cherry tomatoes are placed in an oil bath for low-temperature vacuum oil bath treatment to give the finished product a crispy taste.

[0094] Embodiment 3

[0095] A method for frying peeled cherry tomatoes, characterized in that it comprises at least the following steps:

[0096] S1. Raw material processing: removing the stems of the cherry tomatoes to facilitate the subsequent peeling process; placing the cherry tomatoes after the stems are removed into a washing machine for washing to ensure the surface is clean;

[0097] S2, peeling treatment: treating the washed cherry tomatoes to change the temperature on their surface, thereby promoting the separation between the peel and the flesh;

[0098] S3, withering treatment: the peeled tomatoes need to be heat treated and assisted with peeling to ensure that the peel can be completely removed and the flesh is broken;

[0099] S4. Dehydration: Remove excess water by draining or dehydrating to improve the impregnation efficiency;

[0100] As a preferred embodiment, the water removal treatment in this embodiment adopts any of the following methods:

[0101] The first method: step S4-1, water control: drying the surface moisture by hot air drying with a fan, this step helps to remove excess moisture on the surface of the small red, and improves the efficiency of the immersion; or

[0102] The second method: Step S4-2, dehydration: the soaked cherry tomatoes are placed in a dehydrator for dehydration. This step helps to remove excess water from the cherry tomatoes and improves the efficiency of soaking.

[0103] S5, soaking: soaking the dehydrated cherry tomatoes in the soaking liquid. This step helps to form a color protection effect and ensures that the cherry tomatoes maintain their bright color;

[0104] S6, draining: the soaked tomatoes are drained by the fan on the conveyor belt, and the fan blows away the excess water on the surface, which is conducive to the subsequent quick freezing;

[0105] S7, quick freezing: the drained tomatoes are put into a quick freezing machine for quick freezing, so that the water in the tomatoes is converted from liquid to solid to maintain their freshness and taste;

[0106] S8. Low-temperature vacuum frying: Finally, the processed cherry tomatoes are placed in an oil bath for low-temperature vacuum oil bath treatment to give the finished product a crispy taste.

[0107] Embodiment 4

[0108] This embodiment provides a method for frying small tomatoes after peeling, which is characterized by comprising at least the following steps:

[0109] S1. Raw material processing: removing the stems of the cherry tomatoes to facilitate the subsequent peeling process; placing the cherry tomatoes after the stems are removed into a washing machine for washing to ensure the surface is clean;

[0110] S2, peeling treatment: treating the washed cherry tomatoes to change the temperature on their surface, thereby promoting the separation between the peel and the flesh;

[0111] S3, withering treatment: the peeled tomatoes need to be heat treated and assisted with peeling to ensure that the peel can be completely removed and the flesh is broken;

[0112] S4. Dehydration: Remove excess water by draining or dehydrating to improve the impregnation efficiency;

[0113] S5, soaking: soaking the dehydrated cherry tomatoes in the soaking liquid. This step helps to form a color protection effect and ensures that the cherry tomatoes maintain their bright color;

[0114] As a preferred embodiment, the formula of the impregnation liquid in this embodiment is any one of the following:

[0115] Soaking formula 1: maltodextrin 15-35%, edible salt 1.5-2.5%, maltose syrup 15-55%;

[0116] Dipping formula 2: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, maltose syrup 15-55%;

[0117] Soaking formula 3: maltodextrin 15-35%, edible salt 1.5-2.5%, white sugar 15-35%;

[0118] Dipping formula 4: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, white sugar 15-35%; or

[0119] Dipping formula 5: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, white sugar 15-35%, citric acid 0.5-2%;

[0120] Among them, the type of curing agent in the impregnation formula 1 or the impregnation formula 2 or the impregnation formula 4 or the impregnation formula 5 is any one of calcium chloride, calcium hydroxide or calcium lactate.

[0121] S6, draining: the soaked tomatoes are drained by the fan on the conveyor belt, and the fan blows away the excess water on the surface, which is conducive to the subsequent quick freezing;

[0122] S7, quick freezing: the drained tomatoes are put into a quick freezing machine for quick freezing, so that the water in the tomatoes is converted from liquid to solid to maintain their freshness and taste;

[0123] S8. Low-temperature vacuum frying: Finally, the processed cherry tomatoes are placed in an oil bath for low-temperature vacuum oil bath treatment to give the finished product a crispy taste.

[0124] Embodiment 5

[0125] The fifth embodiment is to select any one of the formulas of the dipping liquid in the fourth embodiment, and provide a method for frying small tomatoes after peeling, characterized in that it comprises at least the following steps:

[0126] S1. Raw material processing: removing the stems of the cherry tomatoes to facilitate the subsequent peeling process; placing the cherry tomatoes after the stems are removed into a washing machine for washing to ensure the surface is clean;

[0127] S2, peeling treatment: treating the washed cherry tomatoes to change the temperature on their surface, thereby promoting the separation between the peel and the flesh;

[0128] S3, withering treatment: the peeled tomatoes need to be heat treated and assisted with peeling to ensure that the peel can be completely removed and the flesh is broken;

[0129] S4. Dehydration: Remove excess water by draining or dehydrating to improve the impregnation efficiency;

[0130] S5, soaking: soaking the dehydrated cherry tomatoes in the soaking liquid. This step helps to form a color protection effect and ensures that the cherry tomatoes maintain their bright color;

[0131] As a preferred embodiment, in step S5-1 of this embodiment, normal pressure immersion: the small tomatoes after being blanched are immersed in a sugar solution of a certain concentration under normal pressure to ensure the taste and color of the small tomatoes;

[0132] Dipping process: Mix 1 times of cherry tomatoes with 1-2 times of dipping solution and soak at a temperature of 15-60°C for 3-12 hours. The dipping solution is prepared according to formula S5.

[0133] As a preferred embodiment, in step S5-2 of this embodiment, vacuum impregnation: the small tomatoes after being blanched are immersed in a sugar solution of a certain concentration under real pressure conditions to ensure the taste and color of the small tomatoes;

[0134] Dipping process: Mix 1 times of cherry tomatoes with 0.5-1.5 times of dipping liquid in a vacuum tumbling machine with a vacuum pressure of 0.05-0.09 MPa and a vacuum time of 20-120 min.

[0135] As a preferred embodiment, in step S5-3 of this embodiment, differential pressure immersion: the withered cherry tomatoes are immersed in a sugar solution of a certain concentration under the condition of continuous circulation of true pressure-normal pressure to ensure the taste and color of the cherry tomatoes;

[0136] Dipping process: Mix 1 times the amount of cherry tomatoes with 0.5-1.5 times the amount of dipping liquid in a vacuum rolling machine, and perform vacuum and normal pressure cycle dipping. First, evacuate the air to a vacuum degree of 0.05-0.09MPa, roll and knead at pressure for 5-20 minutes, then release the air and release the pressure, roll and knead at normal pressure for 5-10 minutes, and repeat the cycle in sequence. The dipping time is 0.5-2h.

[0137] S6, draining: the soaked tomatoes are drained by the fan on the conveyor belt, and the fan blows away the excess water on the surface, which is conducive to the subsequent quick freezing;

[0138] S7, quick freezing: the drained tomatoes are put into a quick freezing machine for quick freezing, so that the water in the tomatoes is converted from liquid to solid to maintain their freshness and taste;

[0139] S8. Low-temperature vacuum frying: Finally, the processed cherry tomatoes are placed in an oil bath for low-temperature vacuum oil bath treatment to give the finished product a crispy taste.

[0140] It should be noted that, based on the above-mentioned embodiments 1 to 5, the following additional explanations are given:

[0141] As a preferred embodiment, in step S8 of this embodiment, a low-temperature vacuum oil bath is performed in the oil bath pot, wherein the frying parameters are: vacuum degree 0.05-0.1MPa, frying temperature 90-120°C, frying time 120-200min, de-oiling speed 150-300R, and de-oiling time 3-10min. Or

[0142] In step S8, a low-temperature vacuum oil bath treatment is performed in the oil bath pot, wherein the frying parameters are: vacuum degree 0.05-0.1 MPa, frying temperature 98° C., frying time 186 min, deoiling speed 200R, and deoiling time 8 min.

[0143] As a preferred embodiment, in this embodiment, after the peeling treatment in step S2 and before the withering treatment in step S3, a plurality of puncture points are formed on the cherry tomatoes using a puncture device to increase the number of holes in the tomato skin and their distribution range, thereby promoting the peeling process; the existing puncture device can be used for puncturing, or the existing device can be improved, for example, the puncture setting includes at least a conveyor belt, parallel baffles, a puncture mechanism and a plurality of needle rows; wherein the cherry tomatoes are transported by the conveyor belt, and the cherry tomatoes are arranged into a neat queue with the help of the parallel baffles, and the puncture mechanism is arranged at the end of the parallel baffles, and when the cherry tomatoes arrive at this position, the puncture mechanism will drive the needle row to perform an up and down reciprocating motion, and the needle row is a clustered needle structure, which can form multiple puncture points at one time to perform puncture operations on the cherry tomatoes.

[0144] It should be noted that the piercing mechanism in this embodiment can adopt the existing piercing mechanism, and those skilled in the art can achieve this by adding parallel baffles and changing the row of needles to cluster needles. In the piercing link, the original device is improved. When the existing equipment is running, batches of tomatoes pass through the row of needles in a disorderly manner, and the small tomatoes transported subsequently push the pierced tomatoes into other equipment or containers. Improvement method: ① Add several parallel baffles to the transportation platform of small tomatoes to make the small tomatoes pass through the row of needles neatly. ② Change the original single row of needles for piercing holes to thinner cluster needles. This can increase the number and distribution area of ​​the holes on the tomato epidermis, which is more conducive to peeling.

[0145] In the above-mentioned embodiments 1 to 5, the dipping formula is further explained:

[0146] 1. Experimental Design

[0147] Design the impregnation liquid formula, the specific parameters are shown in Table 1.1.

[0148] Groups 1 and 7 took 5kg of samples, groups 8 and 9 took 11.5kg of samples (unpeeled), and the other groups took 10kg of samples.

[0149] Table 1.1 Experimental design of dipping formula

[0150]

[0151] Screening of curing agent for impregnation formula:

[0152] After steam peeling (3T / 4s), piercing and blanching (98℃, 110s), 10kg of cherry tomatoes were manually peeled, and the solid-liquid ratio was 1:1.2, the sugar content of the soaking liquid was 40°, and 0.2% of calcium chloride, calcium hydroxide and calcium lactate were added to the soaking liquid respectively. The tests were numbered T-1, T-2 and T-3 to verify the quality and taste.

[0153] Effect of immersion time on the quality of cherry tomatoes:

[0154] Screening of soaking time: After steam peeling (3T / 4s), piercing, and blanching (98℃, 40s), take 10kg of cherry tomatoes peeled manually, according to the material-liquid ratio of 1:1.2, the soaking liquid sugar content of 40°, take the soaking liquid on the large line, soak for 3, 4, 5, 6, 7, 8h, and verify the quality and taste.

[0155] Study on the ratio of material to liquid in vacuum impregnation: After piercing, blanching at 98℃ for 100s, manual peeling, 10kg of millennium, vacuum impregnation process: 0.06MPa, vacuum for 20min, normal pressure for 10min, cycle once, vacuum impregnation for 1h, two groups were made according to this process, the ratio of material to liquid was 0.8:1 and 2:1 respectively. The test numbers are LYB-1 and LYB-2.

[0156] 2. Experimental Purpose

[0157] Through the study of the physical and chemical properties (water content and dry matter) of cherry tomatoes, the dipping formula and production process were optimized, a new dipping method (vacuum dipping) was introduced, and curing agents were added to improve the quality and texture of cherry tomatoes. The large-scale production was synchronized, and theory was combined with practice. During the experiments and production, various experiences were summarized and guided. The large-scale production was made more scientific and traceable.

[0158] 3. Experimental Results

[0159] Dipping recipe

[0160] Begin to prepare the soaking liquid, and wait for 4 hours to observe that all the soaking liquid has melted. The degree of sinking of 2, 3, and 6 is 6>3>2 from high to low. As shown in Table 3.1, maltodextrin has the highest solubility, followed by maltose syrup, and sucrose is the least soluble.

[0161] Table 3.1 Dissolution state of the impregnation solution

[0162]

[0163] As shown in Table 3.2, group 3 absorbed the highest sugar content, and group 5 absorbed the lowest sugar content. This is because sucrose has the highest sugar content. Among them, 0h is the concentration of the soaking liquid, 1-8h is the sugar content of the upper layer of the soaking liquid after the cherry tomatoes are put in, and 9h is the sugar content of the soaking liquid after the cherry tomatoes are taken out and stirred evenly.

[0164] Table 3.2 Changes in sugar content

[0165]

[0166] As shown in Table 3.3, most people chose groups 6 and 7, which were 6 and 9 people respectively. The formula was optimized based on these two groups.

[0167] Table 3.3 Sensory evaluation description of different immersion liquid formulas

[0168]

[0169]

[0170] In this experiment, maltose and maltodextrin have a color-protecting effect; sucrose has the least ideal color, but when sucrose and citric acid are compounded, the color is very good; calcium chloride and sucrose cannot be used together, and citric acid or other types of sugar must be compounded. As shown in Table 3.4, the calcium chloride content in group 1 is high, and the overall color is black, so the amount of calcium chloride added needs to be reduced. The addition of citric acid in group 4 helps color. Group 2 has bright colors, which is due to the addition of maltose.

[0171] Table 3.4 Description of the colors of different impregnation liquid formulas

[0172]

[0173] It can be seen from Table 3.5 that the yield of defective products is between 5.26-6.42, which is higher than the existing large-scale production. The pre-treatment and yield of group 5 are the highest, which is the experimental group of the large-scale formula, followed by group 7. Combined with the tasting results, the taste and yield of groups 6 and 7 are not much different from the large-scale production.

[0174] Table 3.5 Finished products with different impregnation liquid formulas

[0175]

[0176] As shown in Table 3.6, raw material losses occurred in each stage of immersion, and the largest loss occurred in the process of raw material to finished product. This raw material was artificially peeled, not fresh fruit in the warehouse. The losses in Group 5 were relatively small.

[0177] Table 3.6 Loss ratio of different formulas in pre-treatment process %

[0178]

[0179] Screening of curing agents for impregnation formulations

[0180] After adding calcium chloride, calcium hydroxide, and calcium lactate, the pre-treatment yields were 73.32%, 74.68%, and 74.59%, respectively, and the oil bath yields were 4.46, 4.54, and 4.21, respectively. The pre-treatment yields were similar, but the calcium hydroxide tasted strong. The oil bath yields were from high to low in the order of calcium lactate, calcium chloride, and calcium hydroxide. Based on the taste after tasting, it was recommended to add calcium lactate to significantly enhance the taste and texture of cherry tomatoes.

[0181] Although the embodiments of the present invention have been shown and described above, it will be appreciated that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, substitute and vary the above embodiments within the scope of the present invention.

Claims

1. A method for frying small tomatoes after peeling, characterized in that: At least the following steps are included: S1. Raw material processing: removing the stems of the cherry tomatoes to facilitate the subsequent peeling process; placing the cherry tomatoes after the stems are removed into a washing machine for washing to ensure the surface is clean; S2, peeling treatment: treating the washed cherry tomatoes to change the temperature on their surface, thereby promoting the separation between the peel and the flesh; S3, withering treatment: the peeled tomatoes need to be heat treated and assisted with peeling to ensure that the peel can be completely removed and the flesh is broken; S4. Dehydration: Remove excess water by draining or dehydrating to improve the impregnation efficiency; S5, soaking: soaking the dehydrated cherry tomatoes in the soaking liquid. This step helps to form a color protection effect and ensures that the cherry tomatoes maintain their bright color; S6, draining: the soaked tomatoes are drained by the fan on the conveyor belt, and the fan blows away the excess water on the surface, which is conducive to the subsequent quick freezing; S7, quick freezing: the drained tomatoes are put into a quick freezing machine for quick freezing, so that the water in the tomatoes is converted from liquid to solid to maintain their freshness and taste; S8. Low-temperature vacuum frying: Finally, the processed cherry tomatoes are placed in an oil bath for low-temperature vacuum oil bath treatment to give the finished product a crispy taste.

2. The method for frying cherry tomatoes according to claim 1, characterized in that: Peel the washed cherry tomatoes in any of three different ways: The first method: step S2-1, steam heating: heating the washed cherry tomatoes by steam heating to increase the surface temperature thereof, thereby promoting the separation between the peel and the flesh; The parameters of the steam equipment configuration are: feed rate 1.5-3.5t / h, peeling time 3-8s, steam temperature 85-100℃; or The parameters of the steam equipment configuration are: feed rate 3t / h, peeling time 4s, steam temperature 98℃; The second method: step S2-2, steam heating combined with piercing: the washed cherry tomatoes are heated by steam heating, and then conveyed to the piercing device by a conveyor belt for piercing the cherry tomatoes, so that the surface temperature is increased and the surface pores are increased, thereby promoting the separation between the peel and the flesh; Steam parameters: feed rate 1.5-3.5t / h, peeling time 3-8s, steam temperature 85-100℃; Punching parameters: frequency 15-25Hz, which is the frequency at which the punching equipment descends to punch holes; or The third method: Step S2-3, quick freezing combined with steam heating: The washed cherry tomatoes are quick-frozen by a quick-freezing machine, and then peeled by steam heating, so as to promote the separation between the peel and the flesh through the changes of thermal expansion and contraction.

3. The method for frying cherry tomatoes according to claim 2, characterized in that: The killing process is carried out in any of the following ways: The first method: Step S3-1, blanching: blanching the peeled tomatoes with hot water to break the tomatoes and optimize the taste of the flesh; the blanching temperature is 95-100° C. and the blanching time is 40-360 seconds; or The second method: Step S3-2, steaming: steaming the peeled tomatoes to de-cook the tomatoes, reduce the moisture, and promote the soaking of the pulp.

4. The method for frying cherry tomatoes according to claim 3, characterized in that: The water removal treatment is carried out in any of the following ways: The first method: step S4-1, water control: drying the surface moisture by hot air drying with a fan, this step helps to remove excess moisture on the surface of the small red, and improves the efficiency of the immersion; or The second method: Step S4-2, dehydration: the soaked cherry tomatoes are placed in a dehydrator for dehydration. This step helps to remove excess water from the cherry tomatoes and improves the efficiency of soaking.

5. The method for frying cherry tomatoes according to claim 4, characterized in that: The formula of the impregnation solution is any of the following: Soaking formula 1: maltodextrin 15-35%, edible salt 1.5-2.5%, maltose syrup 15-55%; Dipping formula 2: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, maltose syrup 15-55%; Soaking formula 3: maltodextrin 15-35%, edible salt 1.5-2.5%, white sugar 15-35%; Dipping formula 4: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, white sugar 15-35%; or Dipping formula 5: maltodextrin 15-35%, edible salt 1.5-2.5%, curing agent 0.05-0.1%, white sugar 15-35%, citric acid 0.5-2%; Among them, the type of curing agent in the impregnation formula 1 or the impregnation formula 2 or the impregnation formula 4 or the impregnation formula 5 is any one of calcium chloride, calcium hydroxide or calcium lactate.

6. The method for frying cherry tomatoes according to claim 5, characterized in that: Step S5-1, normal pressure immersion: soaking the blanched cherry tomatoes in a sugar solution of a certain concentration under normal pressure to ensure the taste and color of the cherry tomatoes; Dipping process: Mix 1 times of cherry tomatoes with 1-2 times of dipping solution and soak at a temperature of 15-60°C for 3-12 hours. The dipping solution is prepared according to formula S5.

7. The method for frying cherry tomatoes according to claim 6, characterized in that: Step S5-2, vacuum impregnation: Under vacuum conditions, the blanched cherry tomatoes are soaked in a sugar solution of a certain concentration to ensure the taste and color of the cherry tomatoes; Dipping process: Mix 1 times of cherry tomatoes with 0.5-1.5 times of dipping liquid in a vacuum tumbling machine with a vacuum pressure of 0.05-0.09 MPa and a vacuum time of 20-120 min.

8. The method for frying cherry tomatoes according to claim 7, characterized in that: Step S5-3, differential pressure soaking: soaking the withered cherry tomatoes in a sugar solution of a certain concentration under the condition of continuous circulation of true pressure-normal pressure to ensure the taste and color of the cherry tomatoes; Dipping process: Mix 1 times the amount of cherry tomatoes with 0.5-1.5 times the amount of dipping liquid in a vacuum rolling machine, and perform vacuum and normal pressure cycle dipping. First, evacuate the air to a vacuum degree of 0.05-0.09MPa, roll and knead at pressure for 5-20 minutes, then release the air and release the pressure, roll and knead at normal pressure for 5-10 minutes, and repeat the cycle in sequence. The dipping time is 0.5-2h.

9. The method for frying cherry tomatoes according to claim 1, characterized in that: In step S8, a low-temperature vacuum oil bath is performed in the oil bath pot, wherein the frying parameters are: vacuum degree 0.05-0.1 MPa, frying temperature 90-120° C., frying time 120-200 min, de-oiling speed 150-300R, and de-oiling time 3-10 min; or In step S8, a low-temperature vacuum oil bath treatment is performed in the oil bath pot, wherein the frying parameters are: vacuum degree 0.05-0.1 MPa, frying temperature 98° C., frying time 186 min, deoiling speed 200R, and deoiling time 8 min.

10. The method for frying cherry tomatoes according to any one of claims 1 to 9, characterized in that: After the peeling process in step S2 and before the withering process in step S3, a plurality of puncture points are formed on the cherry tomatoes using a piercing device to increase the number of holes on the tomato skin and their distribution range, thereby promoting the peeling process.

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