Pre-baked frozen bread prepared from sour dough fermented by lactic acid bacteria

Abstract

The invention discloses a method for making pre-baked frozen bread by using lactic acid bacteria to ferment sour dough, and belongs to the technical field of food processing. The method is characterized by comprising the following process steps: (1) preparation and storage of sour dough: S10, inoculated fermentation of the sour dough; S20, enlarged culture fermentation of the sour dough; S30, preparation of the sour dough; and S40, storage of the sour dough. And (2) S50, making the pre-baked frozen bread based on the sour dough: uniformly mixing the sour dough with other ingredients, kneading dough, forming, fermenting, baking, packaging, freezing and re-baking. According to the method for making the pre-baked frozen bread by using the sour dough fermentation technology, the flavor characteristics of the pre-baked frozen bread are effectively improved, the tissue structure and freshness of the bread are remarkably improved and the aging rate is delayed through the generation of lactobacillus fermentation metabolites including organic acids and flavor compound precursors (free amino acids) in the sour dough.

Description

Technical Field

[0001] The invention relates to pre-baked frozen bread made from sour dough fermented by lactic acid bacteria, and belongs to the technical field of food processing. Background Art

[0002] Frozen dough technology is widely used in bread production, as it allows consumers to enjoy fresh bread anytime and anywhere through standardized and automated production. In order to solve the problem of freshness of baked products, frozen dough is frozen and stored in a low-temperature environment after production, and finally transported to the baking unit of the retail point for processing. Frozen dough is subdivided into four types: unfermented frozen dough, pre-fermented frozen dough, pre-baked frozen dough and fully baked frozen dough.

[0003] During the production and storage of unfermented frozen dough and pre-fermented frozen dough, the formation and recrystallization of ice crystals will lead to a decrease in yeast activity and destruction of the structure of dough gluten protein, which will lead to deterioration of dough quality. Although pre-baked frozen dough and fully baked frozen dough will not have quality deterioration problems caused by gluten structure destruction, frozen bread will also deteriorate in quality due to temperature fluctuations or accumulation over time during frozen storage, resulting in high hardness, poor elasticity, and rapid aging of frozen bread, affecting the quality of the final product. The main reason is that the formation and growth of ice crystals will cause water migration in the bread, resulting in poor water retention of frozen dough bread.

[0004] At the same time, in order to speed up the production process, improve production efficiency and save production costs, pre-baked frozen bread uses commercial yeast for rapid fermentation. Due to its short fermentation time, the yeast in the dough may not be fully fermented, resulting in insufficient flavor of the pre-baked frozen bread, and the high fermentation temperature leads to an unpleasant fermentation flavor. Summary of the invention

[0005] To solve the above problems, the present invention uses lactic acid bacteria to ferment sourdough and adds it to pre-baked frozen bread in proportion, thereby increasing the specific volume of the bread, reducing the hardness of the bread core, improving the taste of the pre-baked frozen bread, significantly improving the anti-aging properties and flavor properties of the pre-baked frozen bread, and extending the shelf life of the product. The primary purpose of the present invention is to provide a method for preparing pre-baked frozen bread made from sourdough fermented with lactic acid bacteria.

[0006] The present invention is achieved through the following solutions:

[0007] A method for preparing pre-baked frozen bread made from lactic acid bacteria fermented sourdough comprises the steps of preparing and storing the sourdough and preparing the pre-baked frozen bread.

[0008] Preferably, the specific ingredients include the following raw materials by mass: 500-1000 parts of high-gluten flour, 4-12 parts of gluten powder, 10-20 parts of dry yeast, 5-10 parts of salt, 50-100 parts of white sugar, 5-15 parts of improver, 2.5-5 parts of sodium bicarbonate, 25-50 parts of eggs, 20-40 parts of trehalose, 10-20 parts of milk powder, 250-500 parts of water, 100-300 parts of sour dough and 50-100 parts of shortening; the improver includes 3-6 parts of sodium stearoyl lactylate, 0.5-1 part of ascorbic acid, 0.5-1 part of soybean lecithin, 0.5-1 part of glucose oxidase and 0.5-1 part of guar gum.

[0009] Preferably, the preparation and storage of sourdough, including the preparation and storage of sourdough and the making of bread, comprises the following steps:

[0010] S10, sourdough inoculation and fermentation;

[0011] S20, expansion culture and fermentation of sourdough;

[0012] S30, preparation of sourdough;

[0013] S40, storage of sourdough;

[0014] S50. Preparation of pre-baked frozen bread based on sourdough.

[0015] Preferably, the specific preparation process of the sourdough inoculation and fermentation in step S10 is: adding the freeze-dried lactic acid bacteria powder, high-gluten flour and water according to the weight ratio and stirring at a low speed for 1 to 3 minutes, switching to high-speed stirring for 4 to 6 minutes to form a smooth and delicate dough, placing it in a proofing box at a temperature of 26 to 30° C. and a humidity of 72% to 78%, fermenting for 30 to 90 minutes, switching to a low temperature of 2 to 8° C. and refrigerated fermentation for 10 to 12 hours, and obtaining a first generation sourdough.

[0016] Preferably, the lactic acid bacteria is Lactobacillus fermentum KL1115, which is screened and cultivated by the applicant's laboratory, the sourdough is sourdough fermented by Lactobacillus fermentum KL1115, and the raw materials for preparing the sourdough are lactic acid bacteria freeze-dried powder, high-gluten flour and water.

[0017] Preferably, the sourdough formula includes freeze-dried lactic acid bacteria powder, high-gluten flour and water in a weight ratio of 1:100:50.

[0018] Preferably, in order to ensure the fermentation activity of the sourdough, the original strain needs to be activated and cultured for 24 hours twice. The number of times the sourdough is expanded and cultured does not exceed 2 times, and the original strain needs to be reactivated twice.

[0019] Preferably, the lactic acid bacteria inoculation amount of the sourdough is greater than 10 8CFU / g.

[0020] Preferably, the step S20 of expanding the culture and fermentation of the sourdough: expanding the culture of the first generation sourdough, the amount of sourdough added is 10% to 30%, and the conditions of the expanded culture are the same as the temperature and time conditions of the inoculation fermentation in S10.

[0021] Preferably, the preparation of the sourdough in step S30 is as follows: the sourdough obtained after the expanded culture in step S20, high-gluten flour and water are mixed and stirred evenly in a weight ratio of 2:19:9 to form a smooth and delicate dough, which is placed in a proofing box at a temperature of 26-30° C. and a humidity of 72%-78% for fermentation for 30-90 min, and then placed in a refrigerator at a temperature of 2-8° C. for low-temperature refrigeration fermentation for 10-12 h to obtain the sourdough for making frozen bread.

[0022] Preferably, in step S40, the sourdough is stored in a freezer at a temperature of -20 to -16°C, and needs to be taken out of the freezer 12 hours in advance before use and placed in a refrigerator at 0 to 8°C to thaw.

[0023] Preferably, the sourdough is frozen and stored for a maximum of 15 days. If the time is exceeded, the sourdough is put into S20 as the first generation sourdough for expansion culture and fermentation.

[0024] Preferably, the step S30 specifically includes the following contents: ① kneading dough, ② fermentation, ③ packaging and ④ storage.

[0025] Preferably, ① kneading the dough: the sourdough obtained after the expanded culture in step S20, high-gluten flour and water are mixed and stirred evenly in a weight ratio of 2:19:9 to form a smooth and delicate dough.

[0026] Preferably, ② fermentation: the mixed dough is placed in a fermentation box at a temperature of 26-30° C. and a humidity of 72%-78% for fermentation for 30-90 minutes, and then placed in a refrigerator at a temperature of 2-8° C. for low-temperature fermentation for 10-14 hours.

[0027] Preferably, ③ packaging: the fermented sourdough is divided into 10 kg / portions and packed into plastic bags, and the bag openings are tied tightly.

[0028] Preferably, ④ storage: the packaged sourdough is transferred from the refrigerator to a freezer at a temperature of -20 to -16°C for storage.

[0029] Preferably, the preparation of pre-baked frozen bread based on sourdough in S50 comprises the following steps:

[0030] (1) kneading dough, (2) shaping, (3) proofing, (4) baking, (5) freezing, (6) packaging, and (7) re-baking.

[0031] Preferably, (1) kneading the dough: pour all the raw materials (except shortening) into a mixer and stir at a low speed for 2.5 to 3.5 minutes, then switch to a high speed and stir for 1 to 2 minutes, then add 50 to 100 parts of shortening, stir at a low speed for 2.5 to 3.5 minutes, and finally switch to a high speed and stir for 4 to 5 minutes to obtain bread dough.

[0032] Preferably, (2) shaping: pressing the bread dough for 3 to 5 minutes, shaping it through pressing, rolling, squeezing stuffing, pinching and shaping, and arranging it neatly on a baking tray.

[0033] Preferably, (3) proofing: placing the dough in a proofing box at a temperature of 28-32° C. and a humidity of 78%-82% for 120-180 minutes.

[0034] Preferably, (4) baking: placing the proofed dough in an oven, baking at a temperature of 190-200° C. for the upper heat and 170-190° C. for the lower heat, and baking time is 20-25 min.

[0035] Preferably, (5) packaging: after baking, the cake is immediately transferred to a cooling box for cooling, and packaging can be performed after the core temperature is cooled to 25-28°C.

[0036] Preferably, (6) freezing: the cooled bread is immediately placed in a -30 to -40°C quick freezer for 2 to 4 hours, and after the center temperature of the dough reaches -18°C, it is transferred to a -18°C freezer for storage.

[0037] Preferably, (7) re-baking: the frozen pre-baked bread is placed in an oven and baked at a temperature of 170-180° C. for the upper heat and 150-170° C. for the lower heat, and the baking time is 5-15 minutes.

[0038] In summary, the present invention has the following beneficial effects:

[0039] (1) The present invention utilizes lactic acid bacteria fermentation to prepare sourdough, which not only improves the gluten protein structure of the dough, increases the specific volume of the bread, and reduces the hardness of the bread core, but also further enhances the nutritional value and flavor characteristics of the frozen bread through lactic acid bacteria fermentation; further, the sourdough is fermented by lactic acid bacteria at low temperature so that the bread produces alcohols, acids, aldehydes, ketones and esters with fruity and wine aromas, giving the bread a special aroma, increasing the layered sense of the frozen bread flavor, and significantly enhancing the flavor characteristics of the pre-baked frozen bread; the addition of lactic acid bacteria fermented sourdough shortens the mixing time and proofing time of the pre-baked frozen bread, significantly reduces the waiting time for mixing time and fermentation time, improves the production efficiency of the frozen bread, and reduces the production cost of the frozen bread.

[0040] (2) The sourdough used in the present invention is preserved by freezing, does not require drying, saves energy and reduces emissions, is easy to operate, and is suitable for baking companies with a large demand for sourdough.

[0041] (3) Gluten improves the gluten protein structure of sourdough bread dough, strengthens the gluten strength of frozen bread dough, enhances the elasticity, stickiness and chewiness of the bread crumb, and improves the quality of pre-baked frozen bread.

[0042] (4) The present invention adds baking soda to adjust the pH of the dough during the pre-baked frozen bread production process, neutralizes the acidic components of the lactic acid bacteria fermented sourdough, and improves the taste and flavor of the pre-baked frozen bread product.

[0043] (5) Trehalose, sodium stearoyl lactylate, soy lecithin and guar gum in the improver can effectively retain the moisture of bread, reduce moisture migration, improve the softness and elasticity of bread and enhance the quality of bread.

[0044] (6) The texture, taste and flavor of the dough can be improved through the process steps of baking, quick freezing and re-baking, making fresh and delicious bread convenient and quick.

[0045] (7) The pre-baking time of the present invention is close to the full baking time, and the only difference between the pre-baking time and the fresh bread is in color. It only needs to be colored, which greatly shortens the re-baking time and improves the convenience of pre-baking frozen bread.

[0046] (8) The pre-baked frozen bread of the present invention adopts frozen dough technology and does not need to add preservatives. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a process flow chart of preparation and storage of lactic acid bacteria fermented sour dough proposed by the present invention;

[0048] Figure 2 This is a process flow chart of pre-baked frozen bread made by using lactic acid bacteria fermented sourdough proposed by the present invention;

[0049] Figure 3 1. The relationship between the optimal fermentation time and hardness of pre-baked frozen bread in the embodiment

[0050] Figure 4 is a graph showing the relationship between the hardness of pre-baked frozen bread and time in the embodiment;

[0051] Figure 5 is a comparison chart of flavor compounds of pre-baked frozen bread in the embodiment;

[0052] Figure 6 1 is a comparison chart of the peak areas of flavor compounds in the pre-baked frozen bread of the embodiment. DETAILED DESCRIPTION

[0053] The technical solution of the present invention is further defined below in conjunction with specific embodiments, and the technical effects are clearly and completely described so that the purpose, solution and effects of the present invention can be fully understood.

[0054] Example 1

[0055] 1. Preparation and shaping of dough: Pour 1000g high-gluten flour, 20g dry yeast, 10g salt, 100g white sugar, 10g improver, 5g sodium bicarbonate, 50g egg, 30g trehalose, 20g milk powder and 500g water into a blender and stir at low speed for 3min, then stir at high speed for 2min, then add 100g shortening, stir at low speed for 3min, and finally stir at high speed for 4min to obtain bread dough. Press the bread dough for 4min, and then roll the dough, squeeze the filling and pinch the flower to shape it.

[0056] 2. Proofing and baking: Place the dough in a proofing box at 30°C and 80% humidity for 150 minutes; bake in an oven at 200°C on the upper side and 180°C on the lower side for 20 minutes;

[0057] 3. Freezing, packaging and storage of bread: After cooling, the bread should be immediately placed in a -30 to -40℃ quick freezer for 2 to 4 hours. After the center temperature of the dough reaches -18℃, it should be packaged and immediately transferred to a -18℃ freezer for storage.

[0058] 4. Re-baking of pre-baked frozen bread: After the bread has been frozen and stored for one week, thaw it in a constant temperature box at 30℃ and a relative humidity of 85% for 90 minutes. The thawed bread is placed in an oven at 200℃ on the upper side and 180℃ on the lower side and re-baked for 10 minutes to obtain the finished bread.

[0059] Example 2

[0060] 1. Preparation and storage of sourdough: Add freeze-dried lactic acid bacteria powder, high-gluten flour and water in a weight ratio of 1:100:50 and stir at low speed for 3 minutes (lactic acid bacteria inoculation amount>10 8 CFU / g), turn to high speed stirring for 6min to form a smooth and delicate dough, put it in a proofing box at 30℃ and 75% humidity, ferment for 60min, turn to low temperature 8℃ refrigerated fermentation for 11h, and obtain the first generation sour dough. The first generation sour dough is expanded and cultured, the amount of sour dough added is 10%, and the preparation conditions of the expanded culture are the same as those of the first generation. The sour dough, high-gluten flour and water after the expanded culture are prepared according to the weight ratio of 2:19:9 (the conditions are consistent with the preparation conditions of the first and second generation sour doughs), and the prepared sour dough is divided into 10kg / portion and packed into plastic bags, and the bag mouth is tied tightly; it is transferred from the refrigerator to a freezer at a temperature of -18℃ for storage. It needs to be taken out of the freezer 12 hours in advance before use and placed in a 4℃ refrigerator for thawing.

[0061] 2. The dough provided in Example 2 comprises 1000 g of high-gluten flour, 100 g of sour dough, 4 g of gluten, 20 g of dry yeast, 10 g of salt, 100 g of white sugar, 10 g of improver, 5 g of sodium bicarbonate, 50 g of egg, 30 g of trehalose, 20 g of milk powder, 500 g of water and 100 g of shortening.

[0062] 3. Steps 3-5 are the same as steps 1-4 of Example 1 except that the fermentation time is 140 min.

[0063] Example 3

[0064] 1. The preparation and storage steps of sourdough are the same as those in Example 2.

[0065] 2. The dough provided in Example 3 comprises 1000 g of high-gluten flour, 200 g of sour dough, 8 g of gluten, 20 g of dry yeast, 10 g of salt, 100 g of white sugar, 10 g of improver, 5 g of sodium bicarbonate, 50 g of egg, 30 g of trehalose, 20 g of milk powder, 500 g of water and 100 g of shortening.

[0066] 3. Steps 2-5 are the same as steps 1-4 of Example 1 except that the fermentation time is 130 min.

[0067] Example 4

[0068] 1. The preparation and storage steps of sourdough are the same as those in Example 2.

[0069] 2. The dough provided in Example 3 comprises 1000 g of high-gluten flour, 300 g of sour dough, 12 g of gluten, 20 g of dry yeast, 10 g of salt, 100 g of white sugar, 10 g of improver, 5 g of sodium bicarbonate, 50 g of egg, 30 g of trehalose, 20 g of milk powder, 500 g of water and 100 g of shortening.

[0070] 3. Steps 2-5 are the same as steps 1-4 of Example 1 except that the fermentation time is 120 min.

[0071] See also Figure 3 The optimal fermentation time of Example 1, Example 2, Example 3 and Example 4 was optimized and determined to be 150 min, 140 min, 130 min and 120 min, respectively, by F4 fermentation rheometer. With the increase of the amount of sourdough added, the proofing time of pre-baked frozen bread was gradually shortened. The main reason was that the addition of sourdough increased the ductility of the dough, increased the expansion rate of the dough, significantly reduced the fermentation time, improved the production efficiency of frozen bread, and significantly reduced the initial hardness of the pre-baked frozen bread.

[0072] In the above-mentioned Examples 1, 2, 3 and 4, the amount of sourdough added is 0 g, 100 g, 200 g and 300 g respectively. Figure 4 The hardness of the prebaked frozen bread prepared in Example 2, Example 3 and Example 4 after frozen storage for 0 days, 7 days, 14 days and 21 days was compared with that in Example 1. The hardness of the prebaked frozen bread prepared by adding sour dough in Example 2, Example 3 and Example 4 was significantly lower than that in Example 1, indicating that the addition of sour dough can significantly reduce the hardness of prebaked frozen bread and improve the texture characteristics of prebaked frozen bread. By comparing the hardness of the examples within a single storage period, it can be seen that with the increase in the amount of sour dough added, the hardness of the prebaked frozen bread gradually decreases.

[0073] See also Figure 4 After 21 days of frozen storage, the hardness of the pre-baked frozen bread in Example 2, Example 3 and Example 4 with the addition of sourdough was lower than that in Example 1 without the addition of sourdough. The pre-baked frozen bread in Example 3 with the addition of 300g of sourdough had the most significant effect of delaying the aging rate, the best antifreeze protection effect, the extended shelf life, the best freshness-locking effect, the best improvement effect, and was beneficial to the stability of the product.

[0074] See also Figure 5 Compared with Example 1, the types of flavor compounds in Examples 2, 3 and 4 all increased significantly, among which the types of flavor compounds in Example 4 reached the highest, with a total of 37 flavor compounds detected. Therefore, with the increase in the amount of sourdough added, the types of flavor compounds in pre-baked frozen bread showed an increasing trend, which improved the diversity of flavor compounds in pre-baked frozen bread.

[0075] See also Figure 6 The total peak area of ​​flavor compounds in Example 4 is higher than that in other examples, and the total peak areas of acids, alcohols, esters, and aldehydes are much higher than those in Control Example 1, which are increased by 10.97 times, 4.08 times, and 0.68 times, respectively, and have fruity and wine flavors. It can be concluded that as the amount of sourdough added increases, the total peak area of ​​prebaked frozen bread gradually increases, which increases the total amount of aroma and flavor compounds in prebaked frozen bread.

[0076] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pre-baked frozen bread made from lactic acid bacteria fermented sourdough, characterized in that: It includes the preparation, storage and production of sourdough and pre-baked frozen bread. The specific ingredients are as follows: The invention comprises the following raw materials by weight: 500-1000 parts of high-gluten flour, 4-12 parts of gluten powder, 10-20 parts of dry yeast, 5-10 parts of salt, 50-100 parts of white granulated sugar, 5-15 parts of improver, 2.5-5 parts of sodium bicarbonate, 25-50 parts of eggs, 20-40 parts of trehalose, 10-20 parts of milk powder, 250-500 parts of water, 100-300 parts of sour dough and 50-100 parts of shortening; the improver comprises 3-6 parts of sodium stearoyl lactylate, 0.5-1 part of ascorbic acid, 0.5-1 part of soybean lecithin, 0.5-1 part of glucose oxidase and 0.5-1 part of guar gum.

2. The pre-baked frozen bread made from sourdough fermented with lactic acid bacteria according to claim 1, characterized in that: The preparation and storage of sourdough and the making of bread comprise the following steps: S10, sourdough inoculation and fermentation; S20, expansion culture and fermentation of sourdough; S30, preparation of sourdough; S40, storage of sourdough; S50. Preparation of pre-baked frozen bread based on sourdough.

3. The pre-baked frozen bread made from lactic acid bacteria fermented sourdough according to claim 2, characterized in that: The specific preparation process of the sourdough inoculation and fermentation in step S10 is: adding the freeze-dried lactic acid bacteria powder, high-gluten flour and water according to the weight ratio and stirring at a low speed for 1 to 3 minutes, switching to high-speed stirring for 4 to 6 minutes to form a smooth and delicate dough, placing it in a proofing box at a temperature of 26 to 30° C. and a humidity of 72% to 78%, fermenting for 30 to 90 minutes, switching to a low temperature of 2 to 8° C. and refrigerating for fermentation for 10 to 12 hours, and obtaining the first generation sourdough.

4. The pre-baked frozen bread made from sourdough fermented with lactic acid bacteria according to claim 3, characterized in that: The lactic acid bacteria is fermented Lactobacillus KL1115, which is screened and cultivated by the applicant's laboratory. The sourdough is fermented by Lactobacillus KL1115. The raw materials for preparing the sourdough are freeze-dried lactic acid bacteria powder, high-gluten flour and water, and the added weight ratio is 1:100:

50.

5. The pre-baked frozen bread made from sourdough fermented with lactic acid bacteria according to claim 3, characterized in that: The lactic acid bacteria inoculation amount of the sourdough is>10 8 CFU / g. To ensure the fermentation activity of sourdough, the original strain needs to be activated and cultured for 24 hours twice. The number of times the sourdough is expanded and cultured shall not exceed 2 times, and the original strain needs to be reactivated 2 times.

6. The pre-baked frozen bread made from sourdough fermented with lactic acid bacteria according to claim 2, characterized in that: The step S20 of expanding the culture and fermentation of the sourdough: expanding the culture of the first generation sourdough, the amount of sourdough added is 10% to 30%, and the conditions of expanding the culture are the same as the temperature and time conditions of the inoculation fermentation in S10.

7. The pre-baked frozen bread made from sourdough fermented with lactic acid bacteria according to claim 2, characterized in that: Preparation of the sourdough in step S30: the sourdough obtained after the expanded culture in step S20, high-gluten flour and water are mixed and stirred evenly in a weight ratio of 2:19:9 to form a smooth and delicate dough, which is placed in a proofing box at a temperature of 26-30° C. and a humidity of 72%-78%, fermented for 30-90 minutes, and placed in a refrigerator at a temperature of 2-8° C. for low-temperature refrigeration fermentation for 10-12 hours to obtain the sourdough for making frozen bread. Before use, the sourdough needs to be taken out of the freezer 12 hours in advance and placed in a refrigerator at 0-8° C. for thawing.

8. The pre-baked frozen bread made from sourdough fermented with lactic acid bacteria according to claim 2, characterized in that: The step S40 is for storing the sourdough: the sourdough is stored in a freezer at a temperature of -20 to -16°C. The sourdough can be stored in the freezer for up to 15 days. If the storage time is exceeded, the sourdough is put into S20 as the first generation sourdough for expansion culture and fermentation.

9. The pre-baked frozen bread made from sourdough fermented with lactic acid bacteria according to claim 2, characterized in that: Step S30 specifically includes the following contents: ① Mixing the dough: mixing the sourdough obtained after the expanded culture in step S20, high-gluten flour and water in a weight ratio of 2:19:9 to form a smooth and delicate dough; ② Fermentation: Place the mixed dough in a fermentation box at a temperature of 26-30°C and a humidity of 72%-78% for 30-90 minutes, and then place it in a refrigerator at a temperature of 2-8°C for low-temperature fermentation for 10-12 hours; ③ Packaging: Divide the fermented sourdough into 10kg portions and put them into plastic bags, and tie the bags tightly; ④Storage: The packaged sourdough is transferred from the refrigerator to a freezer at a temperature of -20 to -16°C for storage.

10. The pre-baked frozen bread made from sourdough fermented with lactic acid bacteria according to claim 1, characterized in that: The production of pre-baked frozen bread based on sourdough in S50 specifically includes the following steps: (1) Kneading dough: Pour all the raw materials (except shortening) into a mixer and stir at a low speed for 2.5 to 3.5 minutes, then stir at a high speed for 1 to 2 minutes, then add 50 to 100 parts of shortening, stir at a low speed for 2.5 to 3.5 minutes, and finally stir at a high speed for 4 to 5 minutes to obtain bread dough; (2) Forming: Press the bread dough for 3 to 5 minutes, press, roll, squeeze out the filling, and shape it into a shape, and then place it on a baking tray and arrange it neatly; (3) Proofing: Place the dough in a proofing box at a temperature of 28-32° C. and a humidity of 78%-82% to ferment for 120-180 min; (4) Baking: placing the proofed dough in an oven and baking it at a temperature of 190 to 200° C. for the upper heat and 170 to 190° C. for the lower heat for 20 to 25 minutes; (5) Packaging: After baking, transfer to a cooling box for cooling immediately. After cooling to a core temperature of 25-28°C, packaging can be performed. (6) Freezing: After cooling, the bread is immediately placed in a -30 to -40°C quick freezer for 2 to 4 hours. After the center temperature of the dough reaches -18°C, it is transferred to a -18°C freezer for storage. (7) Re-baking: The pre-baked bread stored in the frozen state is placed in an oven and baked at a temperature of 170-180° C. for the upper heat and 150-170° C. for the lower heat for 5-15 minutes.

Images