Lactobacillus fermentum and its application in the preparation of whole wheat sour dough bread fortified with goat milk

Abstract

The invention discloses fermented lactobacillus and its application in the preparation of whole wheat sour dough bread fortified with goat milk; the deposit number of the fermented lactobacillus is GDMCC 62472. The preparation of whole wheat sour dough toast bread fortified with goat milk is to first activate the fermented lactobacillus, dissolve the activated fermented lactobacillus in water and dilute it to prepare an inoculum; whole wheat flour and the inoculum are mixed to prepare whole wheat sour dough, whole wheat sour dough, whole wheat flour, sugar, yeast, salt and water are mixed, and the dough is stirred evenly to prepare the dough, and the dough is put into an oven for baking after secondary proofing after preliminary fermentation and shaping, and the finished bread is obtained by cooling after baking. After adding the sour dough fermented with goat milk and fermented lactobacillus M4, the baking properties such as specific volume, hardness and texture are significantly improved, the shelf life is extended, the characteristics of bread flavor substances are significantly improved, and the estimated glycemic index of bread is reduced.

Description

Technical Field

[0001] The invention relates to the application field of food processing technology, and relates to a fermented lactobacillus capable of improving the comprehensive quality of bread and application thereof in a nutritionally enhanced sour dough whole wheat bread. Technical Background

[0002] China's baking industry is developing rapidly. Compared with regions and countries with similar eating habits, my country's per capita consumption of baked goods still has a lot of room for growth. Consumers are easily attracted by new products and new flavors, so it is particularly important to develop staple foods with palatable flavor, high nutritional value, low energy but strong satiety, and good storage performance. At present, the baking industry urgently needs to improve nutritional fortification methods and production technologies to meet consumers' growing demand for healthy baked goods.

[0003] Applying goat milk, which has a high industrial yield, to baked goods can reduce the original goat smell, complement grains in the composition of essential amino acids, reduce the glycemic index, and improve the overall quality of the product. In addition, converting fresh goat milk, which is prone to quality deterioration, into goat milk powder that can be stored for a long time and has stable quality and further applying it to the production of baked goods can reduce waste and achieve efficient use of goat milk resources. Sourdough technology is a globally recognized method for improving baked goods. This technology is of great significance to the promotion of the industrialization of staple foods in my country and the promotion of whole grain foods in the future.

[0004] Traditional sourdough has a long history of use. It is a dough made by fermenting grains, water, active lactic acid bacteria and yeast. Chinese people generally call sourdough "old dough" or "starter", which is mainly used for steamed bread fermentation. However, the use technology is still limited to the production of handmade pasta products in families or small workshops, and the application foundation is weak. In addition, the preparation process of naturally fermented sourdough also has problems such as unstable quality, difficult quality control, and contamination by miscellaneous bacteria. By artificially adding microorganisms to prepare sourdough, the adverse risks can be minimized. Adding probiotic fermentation to baked foods and increasing the proportion of whole grains can provide better nutritional value and technological content. After baked foods are fermented with potential probiotics, even if the final product has no live bacteria, the postbiotics (including cell components, cell wall components, cell secretions and metabolites) produced during fermentation and baking also have certain physiological functions. In addition, a variety of flavor substances can be produced during the fermentation process. As food ingredients, when they are used in pasta processing, the resulting products have a unique fermented flavor and texture that meet the sensory needs of consumers.

[0005] Chinese invention patent application 201711083419.8 discloses a method for preparing a lipid-lowering and beauty aloe vera grape bread cake, the raw materials including fresh aloe vera, fresh purple grapes, high-gluten flour, purple rice flour, yeast powder, goat milk, butter, salt, low-gluten flour, egg liquid, pullulan, and coconut oil; preparation of aloe vera grape material; putting high-gluten flour, purple rice flour, yeast powder and goat milk into a dough mixer, adding water and stirring until dough-like, taking out and fermenting at a constant temperature to obtain a bread dough; heating the butter until it melts, adding aloe vera grape puree and mixing evenly, putting it into the dough mixer together with the bread dough and stirring, taking it out, placing it in a fermentation box and fermenting at a constant temperature to obtain a bread body; mixing egg liquid, goat milk, pullulan and butter, adding low-gluten flour and aloe vera grape juice and continuing to stir to obtain cake batter; preparing bread cake; it has the functions of reducing internal heat, regulating blood and qi, promoting blood circulation, eliminating fatigue, and protecting the liver and gastrointestinal tract, and can also reduce blood lipids, eliminate toxins, and has the functions of beauty care, improving immunity, anti-cancer, and anti-aging. However, this technology only uses yeast powder, and the flavor and shelf life of bread and cakes need to be improved. In particular, this technology mainly uses the beauty effect of aloe vera itself, without giving full play to the synergistic effect of flour and aloe vera. The goat milk therein only provides nutrition and has no functional effect. Summary of the invention

[0006] The present invention aims to provide a fermented lactobacillus and an application thereof in the preparation of goat milk fortified whole wheat sour dough bread, prepare whole wheat sour dough by using fermented lactobacillus and provide a blood sugar-controlled goat milk fortified whole wheat sour dough bread, improve the nutritional value and digestibility of the bread, extend the shelf life of the bread, and improve the comprehensive quality of the bread.

[0007] The purpose of the present invention is achieved through the following technical solutions:

[0008] A fermented lactobacillus (Limosilactobacillus fermentum M4), whose deposit number is GDMCC62472.

[0009] The method for preparing goat milk fortified whole wheat sour dough toast bread by using the fermented lactobacillus comprises the following steps:

[0010] 1) Activation of Lactobacillus fermentum: inoculating Lactobacillus fermentum M4 into the culture medium and activating it;

[0011] 2) Preparation of fermented sourdough by lactobacillus fermentum: dissolving activated lactobacillus fermentum M4 in water and diluting it to prepare an inoculum; mixing whole wheat flour with the inoculum to prepare whole wheat sourdough with a DY value of 166-200, stirring and mixing thoroughly, and culturing at a constant temperature of 36-38° C.;

[0012] 3) Preparation of bread dough: Mix instant active dry yeast, reconstituted goat milk and fermented lactobacillus sourdough; add whole wheat flour, white sugar and salt, stir and let rise;

[0013] 4) Shaping: Take out the obtained dough and let it stand, divide it into small doughs, roll it into toast shape, put it into toast box, and let it rise;

[0014] 5) Baking: baking the proofed toast-like dough to obtain goat milk fortified whole wheat sour dough toast bread.

[0015] To further achieve the purpose of the present invention, preferably, the activation is that after the fermented lactobacillus (Limosilactobacillus fermentumM4) is inoculated into the MRS liquid culture medium, it is incubated at 36-38°C for 16-18h, then transferred into a fresh MRS liquid culture medium, and then incubated for another 16-18h, centrifuged and the supernatant is discarded; the bacterial sludge is resuspended with sterile water to adjust the bacterial solution concentration to 1-3×10 9 CFU / mL.

[0016] Preferably, the fermented lactobacillus (Limosilactobacillus fermentum M4) is stored in a -80°C refrigerator.

[0017] Preferably, in step 2), the whole wheat flour is 50 to 70 parts by weight; the inoculum is 40 to 50 parts; and the constant temperature culture time at 36-38° C. is 12 to 18 hours.

[0018] Preferably, in terms of weight, in step 3), the instant active dry yeast is 1.0-2.0 parts, the water-reconstituted goat milk is 1-69.7 parts, the fermented lactobacillus sourdough is 1-32 parts, the whole wheat flour is 75-100 parts, the white sugar is 2-5 parts, and the salt is 1-2 parts; step 3) also includes adding shortening in an amount of 1-5.0 parts, which is added after the whole wheat flour, the white sugar and the salt are added.

[0019] Preferably, in parts by mass, the reconstituted goat milk is prepared by dissolving 1 part of pure raw goat milk powder in 6 to 8 parts of distilled water and sterilizing at 100 to 120° C. for 15 to 20 minutes.

[0020] Preferably, the proofing in step 3) is to put the bread dough obtained after adding all the raw materials and stirring into a fermentation basin, seal it, and proof it in an incubator at 32-37° C. for 40-70 minutes.

[0021] Preferably, in step 4), the small dough is covered with plastic wrap and then shaped, bubbles in the dough are squeezed out and then rolled into a toast shape and placed in a toast box; and the proofing in step 4) is performed at 32-37° C. for 40-100 minutes.

[0022] Preferably, in step 5), the baking is carried out in a preheated oven, with the upper temperature being controlled at 190-220°C and the lower temperature being controlled at 210-220°C.

[0023] The MRS broth medium used in the present invention can use the MRS broth medium sold on the market, or can be self-prepared. The preparation method is as follows: 10g of peptone, 10g of beef extract powder, 4g of yeast extract powder, 20g of glucose, 1.08g of Tween-80, 2g of dipotassium hydrogen phosphate, 5g of sodium acetate, 2g of triammonium citrate, 0.2g of magnesium sulfate, and 0.05g of manganese sulfate are weighed respectively, 1L of distilled water is added to fully dissolve, mixed evenly, and then placed in a container that can be sterilized at high temperature, such as a conical flask, and sterilized in a high-pressure sterilizer at 121°C for 15min.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0025] (1) The present invention enhances the nutritional value of bread by fortifying it with goat milk, thereby playing a role in controlling blood sugar. The application of goat milk in bread making can inherit the excellent properties of goat milk and weaken the adverse effects of weak coagulation performance and strong smell. In addition, the additional addition of goat milk can enhance the interaction between starch and protein, reduce the accessibility of α-amylase to starch particles, affect the gelatinization performance of starch during baking, and thus reduce the blood sugar response. The addition of reconstituted goat milk also provides a way for the multi-level utilization of goat milk resources, which can reduce the waste of expiring goat milk.

[0026] (2) Lactobacillus fermentum M4 is a potential probiotic in the present invention, and its application in dough has the characteristics of small inoculum amount, fast growth, fast acid production and gas production. In addition, during dough fermentation and baking, the postbiotics (including cell components, cell wall components, cell secretions and metabolites) produced by Lactobacillus fermentum M4 have certain physiological functions, which endow bread with good functional properties and have nutritional and health value.

[0027] (3) The present invention utilizes potential probiotic strain Lactobacillus fermentum M4 to ferment and prepare sourdough, and prepares nutritionally fortified sourdough, improves the baking and storage quality of whole wheat bread, increases the bread specific volume, reduces the hardness, improves the water holding capacity of bread, and prolongs the shelf life. The use of sourdough fermented by Lactobacillus fermentum M4 can replace the use of bread improvers (hydrophilic colloids, enzyme preparations) to a certain extent, thereby reducing production costs.

[0028] (4) The method for making the whole wheat sour dough bread fortified with goat milk is simple, has the advantages of short production cycle, stable quality, bright outer skin color, uniform inner texture, etc., and meets the dual needs of consumers for health and deliciousness. In addition, no waste is generated during the production process, which is beneficial to environmental protection and effective utilization of resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is the growth curve of Lactobacillus fermentum M4 in the present invention when applied to goat milk fermentation.

[0030] Figure 2 This is a graph showing the total phenol content of Examples 1-3 of the present invention and Comparative Example 1.

[0031] Figure 3 This is a graph showing the ABTS free radical scavenging rates of Examples 1-3 of the present invention and Comparative Example 1.

[0032] Figure 4 It is a cross-sectional view of Examples 6, 7 and Comparative Example 2.

[0033] Figure 5 The starch hydrolysis curves of the noodles obtained in Examples 4-7 and Comparative Examples 1 and 2 are shown. DETAILED DESCRIPTION

[0034] The present invention is further described below in conjunction with the examples and drawings, but the embodiments of the present invention are not limited thereto. It should be noted that if there are processes that are not particularly described in detail below, they can be implemented or understood by those skilled in the art with reference to the prior art. If the manufacturer of the reagents or instruments used is not indicated, they are deemed to be conventional products that can be purchased commercially.

[0035] The rotation speed of the slow stirring in the embodiment of the present invention is 60-80 rpm, and the rotation speed of the fast stirring is 180-240 rpm.

[0036] The MRS broth medium used in the present invention can use the MRS broth medium sold on the market, or can be self-prepared. The preparation method is as follows: 10g of peptone, 10g of beef extract powder, 4g of yeast extract powder, 20g of glucose, 1.08g of Tween-80, 2g of dipotassium hydrogen phosphate, 5g of sodium acetate, 2g of triammonium citrate, 0.2g of magnesium sulfate, and 0.05g of manganese sulfate are weighed respectively, 1L of distilled water is added to fully dissolve, mixed evenly, and then placed in a container that can be sterilized at high temperature, such as a conical flask, and sterilized in a high-pressure sterilizer at 121°C for 15min.

[0037] The fermented lactobacillus (Limosilactobacillus fermentumM4) used in the present invention is separated from tofu yellow pulp water, and is preserved in the Guangdong Microbial Culture Collection Center, with a preservation number of GDMCC 62472, and a preservation location of 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, zip code 510075; the preservation time is May 17, 2022. The whole genome sequencing data sequence of the fermented lactobacillus is as SEQ.ID.NO1. After testing, fermented lactobacillus M4 is a safe and reliable strain.

[0038] The main raw materials include: whole wheat flour produced by Bob's Red Mill Natural Foods, and full-fat raw goat milk powder produced by Shaanxi Red Star Meiling Dairy Co., Ltd.; other raw materials include: high-sugar-tolerant and highly active dry yeast produced by Angel Yeast Co., Ltd., edible low-sodium salt produced by Guangdong Salt Group Co., Ltd., and premium white sugar produced by Swire Sugar (China) Co., Ltd.; shortening is produced by Nanqiao Food Group (Shanghai) Co., Ltd.

[0039] In the process of developing the nutrition-fortified sourdough bread, the present invention conducts specific volume, colorimetry, texture, sensory evaluation, shelf life analysis, volatile flavor, starch content determination and glycemic index test, and the specific method is as follows.

[0040] ① Specific volume and colorimetric determination: Take the baked bread to be tested and cool it at room temperature for 1 hour, then use an electronic balance to measure the mass, which is recorded as the weight of the bread. Put the bread to be tested into a container, use the millet substitution method to determine the volume, completely cover the bread, shake it to fill it, and scrape it flat. Then take out the bread, pour the millet into the measuring cylinder to measure the volume, and subtract the volume of the container from the volume of the millet to obtain the volume of the bread. Specific volume is the volume-to-mass ratio, and the unit is mL / g, with 3 parallels for each formula. For colorimetric determination, adjust the colorimeter to the CIE-L*a*b* color space, and obtain the colorimetric information after zero calibration with a black trap and a white plate respectively.

[0041] ②Full texture and sensory evaluation: The TA-XT Plus texture analyzer was used to perform texture analysis (TPA) on bread according to the AACC 74-09 method. Bread test sample preparation: After the baked bread was cooled at room temperature for 1.5 hours, it was cut into bread slices with a thickness of about 10 mm. The two middle slices were selected and stacked in the center of the sample table of the texture analyzer. The texture analyzer test parameters were set as follows: the P36 / R probe was selected, and the pre-test, test, and post-test speeds were 2.5 mm / s, 1.0 mm / s, and 5.0 mm / s, respectively, the trigger force was 5g (trigger point load), the compression degree was 50% deformation, and the two compression dwell times were 10s. Each sample was measured 6 times to obtain the average value. A 9-point system was used for sensory evaluation, and the evaluation standard was formulated with reference to ISO 6658. The higher the score, the better the acceptance, where 1 to 9 points represent extremely dislike, very dislike, dislike, somewhat dislike, moderate, somewhat like, like, very like, and extremely like.

[0042] ③ Analysis of bread mold and deterioration: Bread samples were packed in polyethylene bags and placed in a constant temperature box at 25±1℃ for one week, and the number of mold colonies on the bread surface was monitored. The criteria for evaluating infection were: no visible colonies (-), 1 colony (+), 2 (++) and 3 or more (+++).

[0043] ④ Analysis of volatile flavor compounds: Headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) were used to detect the aroma volatile substances of whole wheat bread crumbs: In short, 2.5g of fresh bread crumb sample was placed in a 20mL headspace bottle, and the aged automatic sampling extraction probe was inserted. It was placed in the headspace of the headspace bottle at 60℃ for extraction for 40min, and the probe was removed and inserted into the injection port of the gas chromatography-mass spectrometer (280℃), and the volatiles were desorbed in splitless mode for 5min. The capillary column model was Agilent DB-5MS (length 30m, inner diameter 0.25mm, film thickness 0.25μm), the flow rate was 2mL / min, and the carrier gas was helium. The specific program parameters were: 35℃ for 5min, then increased to 50℃ at a rate of 5℃ / min and retained for 5min, and finally increased to 230℃ at a rate of 5.5℃ / min and retained for 5min. The injection hole temperature was 250°C, the ionization mode was EI, the ion source temperature was 200°C, the electron energy was 70eV, the emission current was 200μA, the full scan acquisition mode was adopted, and the mass range was 33-495m / z. The GC-MS spectrum and mass spectrum of the obtained volatiles were matched and retrieved with the NIST 14Library data, and compared and identified with the Kovats index (KI). A match degree higher than 80% was considered reliable. The compounds were quantified by the peak area normalization method.

[0044] ⑤ Determination of fast-digestible starch, slowly-digestible starch and resistant starch content: refer to the in vitro simulated enzyme hydrolysis method proposed by Englyst et al. and combine with the GOPOD kit for determination. First, prepare the enzyme solution, mix 3g of porcine pancreatic enzyme powder with 20mL of distilled water by magnetic stirring for 30min, centrifuge at 4500r / min for 10min, and take 13.5mL of supernatant. Take another 0.7mL of glucosidase to 1.8mL of distilled water and mix it with the above supernatant, refrigerate at 4℃ for use, and prepare the mixed enzyme solution and mix it multiple times according to the number of samples measured each time. Then prepare a pH 5.2 buffer solution, mix 0.1mol / L acetic acid and 0.1mol / L sodium acetate at a ratio of 1:3.7, and add 4mL of 1mol / L CaCl2 solution per liter of buffer solution.

[0045] Weigh 1g (dry basis, the water content is about 7%) of freeze-dried bread crumbs into a 50mL centrifuge tube (add an empty bottle as a blank), vortex mix with 20mL buffer and 1 stirring magnet (simulate gastrointestinal peristalsis environment), and place in a water bath at 37℃ for 15min. Add 5mL of enzyme solution and start the digestion reaction with magnetic stirring at 100r / min. After reacting for 20min, take 0.25mL of the reaction solution into a centrifuge tube containing 10mL of 70% ethanol, take three portions in total, centrifuge at 4500r / min for 5min, take 0.1mL of the supernatant into a small centrifuge tube containing 3mL of GOPOD reagent (prepared in advance in the kit), place in a water bath at 48℃ for 20min, and measure the absorbance at 510nm. Take another 0.1mL of 1mg / mL glucose standard solution (provided in the GOPOD kit) and do the same treatment, and take 0.1mL of distilled water as a blank. After 120 minutes of reaction, take another sample and test it in the same way as the 20-minute reaction solution. Dissolve 50 mg of bread in 6 ml of 2M KOH and shake for 30 minutes. Then add 3 ml of 0.4M sodium acetate and 60 μL of glucosidase and shake in a 60°C water bath for 45 minutes. Finally, centrifuge at 4000 r / min for 10 minutes, and use the GOPOD kit to determine the glucose concentration in the supernatant and calculate the total starch content (TS) with a conversion factor of 0.9. The calculation methods for rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) are as follows.

[0046] RDS(%)=(G20-FG)×0.9 / TS

[0047] SDS (%) = (G120-G20) × 0.9 / TS

[0048] RS (%) = [TS - (RDS + SDS)] / TS

[0049] Where: G20 is the glucose content produced after 20 minutes of hydrolysis (mg); FG is the free glucose content in starch before treatment (mg); G120 is the glucose content produced after 120 minutes of hydrolysis (mg); TS is the total starch content (mg).

[0050] ⑥ Determination of eGI value: First, prepare the enzyme solution. Mix 3g of porcine pancreatic enzyme powder with 20mL of distilled water by magnetic stirring for 30min, centrifuge at 4500r / min for 10min, and take 13.5mL of supernatant. Take another 0.7mL of glucosidase and mix it with 1.8mL of distilled water, mix it with the above supernatant, and refrigerate it at 4℃ for use. Prepare the mixed enzyme solution several times and mix it according to the number of samples measured each time. Then prepare a pH 5.2 buffer solution, mix 0.1mol / L acetic acid and 0.1mol / L sodium acetate at a ratio of 1:3.7, and add 4mL of 1mol / L CaCl2 solution per liter of buffer solution. Pepsin solution is prepared by mixing 0.2g of pepsin with 10mL of distilled water.

[0051] Take a 250mL conical flask and add 1 magnetic particle to it, take 1g of freeze-dried bread crumbs to the conical flask, add 20mL of distilled water, and make a blank control at the same time. Use hydrochloric acid (5% w / w 4mL) to adjust the solution pH to 1.2 (record the amount of hydrochloric acid used), add 1mL of 2% pepsin solution and incubate in a 37℃ water bath shaker, and make a blank at the same time. After incubation for 30min, take 0.5mL of digestion solution to measure glucose equivalent, record it as the glucose equivalent of 0min, and at the same time use 2mL 1M NaOH solution and dropper to add a few drops of 0.1M NaOH solution (record the amount of NaOH used) to adjust the incubation solution pH to 5.2, add 5mL of mixed enzyme, continue to digest in the shaker, take 0.5mL of digestion solution at 10, 20, 40, 60, 80, 120, 160, 180min respectively, and use GOPOD method to determine the glucose equivalent in the incubation solution. The starch hydrolysis rate of the sample at each time point during the digestion process was calculated based on the glucose equivalent in the hatching solution. The starch hydrolysis curve follows: C = C ∞ (1-e -kt ), C is the hydrolysis rate of starch in samples at different time points, t represents the digestion time, C ∞ It indicates the equilibrium value of the hydrolysis rate of starch in the sample after 180 minutes of digestion, and k is the first-order reaction kinetic constant. 白面包 =1.281×10 4 .

[0052]

[0053]

[0054] eGI=(0.862×HI)+8.198

[0055] After using the Origin 2021 fitting function, the hydrolysis index (HI) and estimated glycemic index of different whole wheat breads can be calculated according to the formula. The estimated value of the glycemic index (eGI) is calculated according to the formula derived by Granfeldt et al. r represents the end time of digestion (i.e. 180 min), t o Represents the digestion start time (i.e. 0 min).

[0056] ⑦ Determination of polyphenol content: First, prepare the polyphenol extract: with some modifications based on the predecessors. Crush the eight kinds of bread core capsules after vacuum freeze drying, take 2g of powder respectively and add 25mL of 80% methanol solution, extract in the dark for 2h at 37℃ and 900r / min magnetic stirring, then ultrasonicate for 30min. Centrifuge the extract at 5500r / min for 10min, take the supernatant for later use, then add 25mL of 80% methanol solution to the remaining residue and repeat the extraction in the same way, combine the supernatants of the two extractions, mix well and store in a refrigerator at 4℃ away from light for further analysis.

[99] .

[0057] The polyphenol content was determined by the Folin-Ciocalteau method: 1 mL of polyphenol extract was taken, 1 mL of Folin-Ciocalteau reagent (diluted with 5 times the volume of water) and 3 mL of water were added, and after shaking, 5 mL of 10% Na2CO3 (v / v) solution was added, and after shaking, the mixture was allowed to stand at room temperature in the dark for 30 minutes. Then, the mixture was centrifuged at 5500 r / min for 5 minutes, and the absorbance of the supernatant was determined (the test wavelength was 725 nm). A standard curve was made based on gallic acid, and the total phenol content in bread was expressed as gallic acid equivalent (GAE) (i.e., mg gallic acid / g bread powder mass).

[0058] ⑧Antioxidant activity analysis (ABTS·free radical scavenging) method:

[0059] Prepare ABTS (7mmol / L) and potassium persulfate (2.45mmol / L) solutions respectively, mix equal amounts and react in the dark for 16 hours to obtain ABTS+· stock solution. Then adjust the absorbance of the stock solution to 0.70±0.05 (wavelength of 734nm) with distilled water as ABTS+· reaction solution (prepare and use immediately). Take 3mL ABTS+· reaction solution, add 0.4mL bread extract, shake and let stand at room temperature for 30min, take the supernatant after centrifugation and measure the absorbance at 734nm wavelength. The control group is replaced by distilled water instead of bread extract, and the blank group is replaced by distilled water instead of ABTS+· reaction solution. The free radical scavenging ability of bread ABTS is expressed as VC equivalent (VCE) (mgVC / g bread powder mass).

[0060] Example 1: Whole genome sequence analysis of Lactobacillus fermentum M4

[0061] (1) The whole genome sequence of Lactobacillus fermentum M4 was determined by combining the third-generation ONT and the second-generation Illumina technology. The 16s rDNA sequence of Lactobacillus fermentum M4 is shown in SEQ.ID.NO 1. The results showed that the genome of Lactobacillus fermentum M4 contained a 2,032,184 bp circular chromosome with an average G+C content of 51.75%.

[0062] (2) Genes were annotated using the comprehensive antibiotic resistance (CARD) non-redundant protein sequence (Nr) database. The results showed that Lactobacillus fermentum M4 had no antibiotic resistance genes but contained genes related to gastrointestinal tolerance such as acid resistance, bile salt resistance, and adhesion, which was consistent with previous phenotypic studies.

[0063] (3) The pathogenic gene databases (PHI, VFDB) were used to search for potential pathogenic or virulence genes in the genome of Lactobacillus fermentum M4. The results showed that Lactobacillus fermentum M4 did not contain any virulence or pathogenic genes and was a safe and reliable potential probiotic strain.

[0064] (4) Sugar utilization experiments showed that Lactobacillus fermentum M4 can utilize glucose, lactose, fructose, xylose, raffinose, stachyose, xylan, sucrose, maltose, etc. in a variety of different matrices, which is consistent with the results of carbohydrate function annotation, laying the foundation for its growth in a variety of different matrices.

[0065] Example 2: Growth curve of Lactobacillus fermentum M4 in goat milk

[0066] (1) The preparation method of reconstituted goat milk is as follows: 1 portion (49 g) of pure raw goat milk powder (protein content 25 g / 100 g) is dissolved in 6.143 portions (301 g) of distilled water and sterilized at 100°C for 15 min, and then cooled to obtain goat milk. When used in subsequent bread making, in order to adjust the similar water and solid content in the dough, the sample containing goat milk should add more goat milk and less flour.

[0067] (2) Growth curve of Lactobacillus fermentum M4 in goat milk: Before sterilizing goat milk, sucrose was added at a ratio of 2% to ensure sufficient carbon source. Samples were taken every 2 hours for gradient dilution, and appropriate concentrations were selected for plating on MRS agar plates. After 24 hours, live bacteria were counted and the average value was taken after three replicates.

[0068] Depend on Figure 1 It can be seen that Lactobacillus fermentum M4 has a concentration of 3.1×10 5 CFU / mL was added to goat milk (with sugar). There was only a short stagnation before entering the logarithmic growth phase, which showed that M4 had strong adaptability to the goat milk matrix. The colony count of Lactobacillus fermentum M4 reached 10 after 12 hours. 10 CFU / mL, the bacterial count reached 10 after 20 hours. 11 CFU / mL, that is, it shows the characteristics of fast growth and rapid acid production during goat milk fermentation.

[0069] Example 3: Growth and fermentation of Lactobacillus fermentum M4 in whole wheat dough

[0070] Growth and fermentation experiment: In whole wheat dough, the initial concentration of 6.60 log (CFU / g) was inoculated with fermented lactobacillus (Limosilactobacillus fermentumM4). After 12 hours of fermentation, the bacterial count reached 9.81 log (CFU / g). After 21 hours of fermentation, the count reached 10.02 log (CFU / g). In addition, the pH can be reduced to below 4.0 after 12 hours of fermentation, which shows that the fermented lactobacillus has good growth and fermentation ability in the whole wheat dough system.

[0071] In addition, Lactobacillus fermentum M4 has a rich carbohydrate hydrolase system (it can make good use of carbohydrates such as maltose, sucrose, and xylan in the sourdough environment), a strong proteolytic system, and the potential to synthesize amino acids, B vitamins, and phenolic acid metabolism. The strong acid production ability is mainly related to 7 L-lactate dehydrogenase genes. These excellent adaptability and metabolic characteristics provide a theoretical basis for it to be a potential sourdough starter.

[0072] Example 4: Sourdough whole wheat bread fermented by Lactobacillus fermentum M4

[0073] (1) Activation of Lactobacillus fermentum: Take out the glycerol frozen tube of Lactobacillus fermentum M4 from the -80°C refrigerator, take 50 μL of Lactobacillus fermentum M4 and inoculate it into 5 ml of MRS liquid culture medium, incubate it at 37°C for 18 h, take 100 μL and transfer it into 10 mL of fresh MRS liquid culture medium, incubate it for another 18 h, centrifuge it at 4500 r / min and discard the supernatant; resuspend the bacterial sludge with sterile water and adjust the bacterial solution concentration to about 10 9 CFU / mL, set aside.

[0074] (2) Preparation of fermented sourdough with Lactobacillus fermentum: 66.67 (187.5 g) of whole wheat flour was mixed with 44.44 (125 g) of inoculum (3:2) to prepare whole wheat sourdough with a DY value of 166.7. The initial concentration of Lactobacillus fermentum M4 entering the dough was ensured to be 10 6 (CFU / g) or more, stir and mix thoroughly, and incubate at 37°C for 12 hours. Among them, the DY value (Doughyield) can reflect the ratio of flour to water, and the calculation method is DY = (flour weight + water weight) / flour weight * 100, that is, 100 times the ratio of dough weight to flour weight.

[0075] (3) Preparation of bread dough: Add 1.0 (2.8125 g) parts of instant active dry yeast, 53.33 (150 g) parts of water and the obtained mature fermented lactobacillus sour dough (about 32 (90 g) parts by weight), and stir at low speed for 1 minute. Then, take 80 (225 g) parts of whole wheat flour, 2.0 (5.625 g) parts of white sugar, and 1.0 (2.8125 g) parts of salt into a mixing tank and stir at low speed for 2 minutes, stir quickly for 3 minutes, and finally stir at low speed for 1 minute; take out the dough, put it into a fermentation bowl, seal it, and let it rise in an incubator at 37°C for 70 minutes.

[0076] (4) Shaping and baking of bread dough: Take out the obtained dough and let it stand for 5 minutes, then divide it into small dough pieces of about 150g each, cover it with plastic wrap again for 10 minutes and shape it, squeeze out the bubbles in the dough with a rolling pin, roll it into a toast shape and put it in a toast box, and let it rise at 37℃ for 100 minutes. Then put it in a preheated oven and bake it at 220℃ for 35 minutes to obtain whole wheat sour dough bread.

[0077] The results of baking and sensory quality analysis showed that the specific volume of whole wheat sourdough bread was 3.11 cm 3 / g, hardness was 34.67N, brightness was 52.08, and sensory score was 6.9 points. A total of 53 flavor compounds were detected (see Table 2). The results of nutritional and storage quality analysis showed (see Table 3 and Table 4) that whole wheat sour dough bread grew visible colonies on the fifth day of storage at room temperature. The total phenol content was 1.4352mg / g ( Figure 2 ), the estimated glycemic index eGI is 65.24.

[0078] Example 5: Sourdough goat milk whole wheat bread fermented by Lactobacillus fermentation M4 1

[0079] (1) Activation of Lactobacillus fermentum: Take out the glycerol frozen tube of Lactobacillus fermentum M4 from the -80°C refrigerator, take 50 μL of Lactobacillus fermentum M4 and inoculate it into 5 ml of MRS liquid culture medium, incubate it at 37°C for 18 h, take 100 μL and transfer it into 10 mL of fresh MRS liquid culture medium, incubate it for another 18 h, centrifuge it at 4500 r / min and discard the supernatant; resuspend the bacterial sludge with sterile water and adjust the bacterial solution concentration to about 10 9 CFU / mL, set aside.

[0080] (2) Preparation of fermented sourdough with Lactobacillus fermentum: Resuspend the mixture with sterile water and adjust the concentration of the bacteria to approximately 10 9 CFU / mL, set aside. Dissolve the cultured and collected bacteria in water to prepare an inoculum (dilution), mix 66.67 (187.5 g) of whole wheat flour with 44.44 (125 g) of the inoculum (3:2) to prepare a whole wheat sourdough with a DY value of 166.7. Ensure that the initial concentration of the fermented Lactobacillus M4 entering the dough is 10 6 (CFU / g) or above, stir well to mix, and culture at 37℃ for 12h before use.

[0081] (3) The preparation method of reconstituted goat milk is as follows: 1 portion (49 g) of pure raw goat milk powder (protein content 25 g / 100 g) is dissolved in 6.143 portions (301 g) of distilled water and sterilized at 100°C for 15 min, and then the goat milk is obtained after cooling. When used in bread making, in order to adjust the similar water and solid content in the dough, the sample containing goat milk can add more goat milk and less flour.

[0082] (4) Preparation of bread dough: Add 1.0 (2.8125 g) of instant active dry yeast, 54 (151.92 g) of reconstituted goat milk and the mature fermented lactobacillus sour dough obtained previously (about 32 (90 g) by weight), and stir at low speed for 1 minute. Then, take 75 (211 g) of whole wheat flour, 2.0 (5.625 g) of white sugar, and 1.0 (2.8125 g) of salt and put them into a mixing bowl and stir at low speed for 2 minutes, stir quickly for 3 minutes, and finally stir at low speed for 1 minute; take out the dough, put it into a fermentation bowl, seal it, and proof it in a 37°C incubator for 70 minutes.

[0083] (5) Shaping and baking of bread dough: The obtained dough was taken out and allowed to stand for 5 minutes, and then divided into small dough pieces of about 150 g each. The dough pieces were covered with plastic wrap again for 10 minutes and shaped. The bubbles in the dough were squeezed out with a rolling pin, and the dough pieces were rolled into a toast shape and placed in a toast box. The dough pieces were proofed at 37° C. for 100 minutes. The dough pieces were then placed in a preheated oven and baked at 220° C. for 35 minutes, and Example 5 was obtained.

[0084] The baking and sensory quality test results showed that the specific volume of goat milk fortified whole wheat sourdough bread (Example 5) was 2.72 cm 3 / g, hardness is 42.05N, brightness is 56.11, and sensory score is 7.3 points. A total of 45 flavor compounds were detected (see Table 2), and the types were also significantly improved. In addition, the concentration of flavor substances was higher than that of other samples. The total amount of acids, esters, and aldehydes was much higher than that of Example 3, which was increased by 10.97 times, 4.08 times, and 0.68 times. The results of nutritional and storage quality determination (see Tables 3 and 4) showed that the whole wheat sourdough bread fortified with goat milk grew visible colonies on the fourth day of storage at room temperature, and had a longer shelf life. The total phenol content was 1.5404 mg / g ( Figure 2 ), the estimated glycemic index eGI is 64.07.

[0085] Example 6 Lactobacillus fermented M4 fermented sourdough goat milk whole wheat bread 2 (containing shortening)

[0086] (1) Activation of Lactobacillus fermentum: Take out the glycerol frozen tube of Lactobacillus fermentum M4 from the -80°C refrigerator, take 50 μL of Lactobacillus fermentum M4 and inoculate it into 5 ml of MRS liquid medium, incubate it at 37°C for 16 h, take 70 μL and transfer it into 5 mL of fresh MRS liquid medium, incubate it for another 16 h, centrifuge it at 4500 r / min and discard the supernatant; resuspend the bacterial sludge with sterile water and adjust the bacterial solution concentration to about 10 9 CFU / mL, set aside.

[0087] (2) Preparation of fermented sourdough with Lactobacillus fermentum: Resuspend the mixture with sterile water and adjust the concentration of the bacteria to approximately 10 9 CFU / mL, set aside. Dissolve the cultured and collected bacteria in water to prepare an inoculum (dilution), mix 50 parts (140.625g) of whole wheat flour with 50 parts (140.625g) of the inoculum (1:1) to prepare a whole wheat sourdough with a DY value of 200.0. Ensure that the initial concentration of the fermented Lactobacillus M4 entering the dough is 10 6 (CFU / g) or above, stir well to mix, and culture at 37℃ for 18h.

[0088] (3) The preparation method of reconstituted goat milk is as follows: 1 portion (49 g) of pure raw goat milk powder (protein content 25 g / 100 g) is dissolved in 8 portions (392 g) of distilled water and sterilized at 120°C for 20 min, and then cooled to obtain goat milk. When used in bread making, in order to adjust the similar water and solid content in the dough, the sample containing goat milk should add more goat milk and less flour.

[0089] (4) Preparation of bread dough: Add 2.0 (5.625 g) parts of instant active dry yeast, 60 (168.75 g) parts of reconstituted goat milk and the previously obtained mature fermented lactobacillus sour dough (about 32 (90 g) parts by weight), and stir at low speed for 1 minute. Then, take 75 (211 g) parts of whole wheat flour, 5.0 (14.0625 g) parts of white sugar, and 2.0 (5.625 g) parts of salt and put them into a mixing tank and stir at low speed for 2 minutes, add 5.0 (14.0625 g) parts of shortening and stir quickly for 3 minutes, and finally stir at low speed for 1 minute; take out the dough, put it into a fermentation bowl, seal it, and proof it in a 32°C incubator for 40 minutes.

[0090] (5) Shaping and baking of bread dough: The obtained dough was taken out and allowed to stand for 5 minutes, then divided into small dough pieces of about 150 g each, and covered with plastic wrap again for 10 minutes to set the dough, and the bubbles in the dough were squeezed out with a rolling pin, and the dough was rolled into a toast shape and placed in a toast box, and allowed to rise at 37° C. for 40 minutes. Then, the dough was placed in a preheated oven and baked for 30 minutes at 200° C. for the upper fire and 220° C. for the lower fire, to obtain Example 6.

[0091] The sensory score of whole wheat sourdough bread fortified with goat milk (with shortening) was 7.8 points. Sensoryly, due to the fermentation time and amount of water added to the whole wheat sourdough, as well as the reduced concentration of goat milk, the bread had a slightly sticky feeling, the sour taste was slightly stronger than other samples, and the bread was darker in color. Due to the long fermentation time, the bread eventually had more holes, and the uniformity of the bubbles was average.

[0092] The estimated glycemic index (eGI) of whole-wheat sourdough bread fortified with goat's milk (with shortening) is 68.83.

[0093] Example 7 Lactobacillus fermented M4 fermented sourdough goat milk whole wheat bread 3 (containing shortening)

[0094] (1) Activation of Lactobacillus fermentum: Take out the glycerol frozen tube of Lactobacillus fermentum M4 from the -80°C refrigerator, take 50 μL of Lactobacillus fermentum M4 and inoculate it into 5 ml of MRS liquid medium, incubate it at 37°C for 16 h, take 70 μL and transfer it into 5 mL of fresh MRS liquid medium, incubate it for another 16 h, centrifuge it at 4500 r / min and discard the supernatant; resuspend the bacterial sludge with sterile water and adjust the bacterial solution concentration to about 10 9 CFU / mL, set aside.

[0095] (2) Preparation of fermented sourdough with Lactobacillus fermentum: Resuspend the mixture with sterile water and adjust the concentration of the bacteria to approximately 10 9 CFU / mL, set aside. Dissolve the cultured and collected bacteria in water to prepare an inoculum (dilution), mix 66.67 parts (187.5g) of whole wheat flour with 44.44 parts (125g) of inoculum (1:1) to prepare a whole wheat sourdough with a DY value of 166.7. Ensure that the initial concentration of fermented Lactobacillus M4 entering the dough is 10 6 (CFU / g) or above, stir well to mix, and culture at 37℃ for 14h before use.

[0096] (3) The preparation method of reconstituted goat milk is as follows: 1 portion (49 g) of pure raw goat milk powder (protein content 25 g / 100 g) is dissolved in 6 portions (301 g) of distilled water and sterilized at 120°C for 20 min, and then cooled to obtain goat milk. When used in bread making, in order to adjust the similar water and solid content in the dough, the sample containing goat milk should add more goat milk and less flour.

[0097] (4) Preparation of bread dough: Add 2.0 (5.625 g) parts of instant active dry yeast, 60 (168.75 g) parts of reconstituted goat milk and the mature fermented lactobacillus sour dough obtained previously (about 32 (90 g) parts by weight), and stir at low speed for 1 minute. Then, take 75 (211 g) parts of whole wheat flour, 5.0 (14.0625 g) parts of white sugar, and 2.0 (5.625 g) parts of salt and put them into a mixing bowl and stir at low speed for 2 minutes, add 5.0 (14.0625 g) parts of shortening and stir quickly for 3 minutes, and finally stir at low speed for 1 minute; take out the dough, put it into a fermentation bowl, seal it, and proof it in an incubator at 37°C for 45 minutes.

[0098] (5) Shaping and baking of bread dough: The obtained dough was taken out and allowed to stand for 5 minutes, then divided into small dough pieces of about 150 g each, and covered with plastic wrap again for 10 minutes before shaping. The bubbles in the dough were squeezed out with a rolling pin, and the dough was rolled into a toast shape and placed in a toast box, and allowed to rise at 37° C. for 40 minutes. Then, the dough was placed in a preheated oven and baked at 210° C. for the upper heat and 220° C. for the lower heat, to obtain Example 6.

[0099] The sensory score of goat milk fortified whole wheat sourdough bread (with shortening) was 8.3 points. The bread has a strong goat milk and sourdough flavor, and the color is better than other samples. The acidity is appropriate, the texture is soft, the foam is uniform, and the acceptability is the best.

[0100] The estimated glycemic index (eGI) of whole-wheat sourdough bread fortified with goat's milk (with shortening) is 67.27.

[0101] Comparative Example 1: Whole Wheat Bread 1

[0102] (1) Preparation of bread dough: Add 1.0 (2.8125 g) parts of instant active dry yeast and 66.67 (187.5 g) parts of water, and stir at low speed for 1 minute. Then, add 100 (281.25 g) parts of whole wheat flour, 2.0 (5.625 g) parts of white sugar, and 1.0 (2.8125 g) parts of salt into a mixing bowl and stir at low speed for 2 minutes, stir quickly for 3 minutes, and finally stir at low speed for 1 minute; take out the dough, put it into a fermentation bowl, seal it, and let it rise in an incubator at 37°C for 70 minutes.

[0103] (2) Shaping and baking of bread dough: The obtained dough was taken out and allowed to stand for 5 minutes, and then divided into small dough pieces of about 150 g each. The dough pieces were covered with plastic wrap again for 10 minutes and then shaped. The bubbles in the dough were squeezed out with a rolling pin, and the dough pieces were rolled into a toast shape and placed in a toast box. The dough pieces were proofed at 37° C. for 100 minutes. The dough pieces were then placed in a preheated oven and baked at 220° C. for 35 minutes, thereby obtaining Comparative Example 1.

[0104] The results of baking and sensory quality test show (see Table 1) that the specific volume of ordinary whole wheat bread (Comparative Example 1) is 2.67 cm 3 / g, hardness of 47.90N, brightness of 55.94, sensory score of 7.0 points. A total of 39 volatile compounds were detected (see Table 2), with the types and contents of alcohols, esters and aldehydes being the least. The results of nutritional and storage quality determination (see Tables 3 and 4) showed that ordinary whole wheat bread grew a visible colony on the third day of storage at room temperature, and the shelf life was short. The total phenol content was 1.3385mg / g ( Figure 2 ), the estimated glycemic index eGI is 78.01.

[0105] Comparative Example 2: Whole Wheat Bread 2 (Containing Shortening)

[0106] (1) Preparation of bread dough: Add 2.0 (5.625 g) parts of instant active dry yeast and 66.67 (187.5 g) parts of water and stir at low speed for 1 minute. Then, put 100 (281.25 g) parts of whole wheat flour, 2.5 (14.0625 g) parts of white sugar and 2.0 (5.625 g) parts of salt into a mixing bowl and stir at low speed for 2 minutes. Add 5.0 (14.0625 g) parts of shortening and stir rapidly for 3 minutes, and finally stir at low speed for 1 minute. Take out the dough, put it into a fermentation bowl, seal it, and let it rise in an incubator at 37°C for 50 minutes.

[0107] (2) Shaping and baking of bread dough: The obtained dough was taken out and allowed to stand for 5 minutes, and then divided into small dough pieces of about 100 g each. The dough was covered with plastic wrap again for 10 minutes and shaped. The bubbles in the dough were squeezed out with a rolling pin, and the dough was rolled into a toast shape and placed in a toast box. The dough was proofed at 37° C. for 40 minutes. The dough was then placed in a preheated oven and baked at 190° C. for 30 minutes, with the upper heat at 190° C. and the lower heat at 210° C., to obtain the comparative example 2.

[0108] The sensory score of regular whole wheat bread (with shortening) was 7.2 points. The taste of whole wheat bread is average, slightly rough, and the flavor is average.

[0109] The estimated glycemic index (eGI) of ordinary whole wheat bread (with shortening) is 80.52.

[0110] Figure 4 From left to right are the cross-sectional views of Examples 6, 7 and Comparative Example 2. It can be seen from the figures that the products prepared in Examples 6, 7 and Comparative Example 2 are obviously bread.

[0111] Figure 5 The starch hydrolysis curves of the noodles obtained in Examples 4-7 and Comparative Examples 1 and 2 show that the hydrolysis performance of the embodiments of the present invention is substantially similar to that of the comparative examples.

[0112] As can be seen from the above examples, the sourdough prepared by adding fermented Lactobacillus M4 can significantly increase the specific volume of bread and reduce the hardness, while the addition of goat milk can reduce the specific volume of bread and increase the hardness. Compared with Comparative Example 1, the hardness of Example 3 increased by about 29.8%. By combining sourdough treatment, the hardness of Example 5 was reduced to a level lower than that of Comparative Example 1, that is, the sourdough weakened the adverse texture effect caused by goat milk fortification.

[0113] From the above examples, it can be seen that the addition of goat milk increases the L*, a*, and b* of the bread crumb, especially the overall brightness of the bread, and the addition of sourdough reduces the brightness to a certain extent. In addition, Examples 5 and 6 have higher sensory scores, that is, the use of goat milk combined with fermented Lactobacillus M4 to prepare sourdough improves the overall sensory properties of bread.

[0114] The volatile flavor substances of different whole wheat breads in the embodiments of the present invention were clustered and analyzed by heat map test. In the test, red represents a higher content and blue represents a lower content. The results of the determination of volatile flavor substances further confirmed the significant differences in the flavor substance composition brought by goat milk and sourdough. The content of substances such as hexanal and oxalic acid was reduced due to the addition of goat milk, but the relative content of many esters and aldehydes was increased. The results show that goat milk fortification has a significant effect on the flavor of bread. There are also obvious differences between the group of sourdough fermented with Lactobacillus fermentation M4 and the sourdough group. Among them, acetic acid, various aldehydes and esters are the main substances that cause the flavor differences between the two types of bread. For example, the content of 2-nonenal, decanal, 2,4-decanal, nonanal, 3-methyl-1-butanol (floral and fruity aroma) has been significantly improved, which gives the sourdough bread a unique flavor, so that Examples 4 and 5 have good sensory properties.

[0115] It can be seen from the above examples that the sourdough prepared by fermenting Lactobacillus fermentum M4 for 12 hours can inhibit the growth of mold in whole wheat bread to a certain extent, and extend the shelf life of whole wheat bread by 1 to 2 days compared with the control group.

[0116] From the above examples, it can be seen that the whole wheat bread (Example 5) improved by goat milk and fermented Lactobacillus fermentum M4 fermentation has the highest total phenol content among all breads (1.540 mg / g), which is about 1.15 times that of comparative example 1. The free radical scavenging ability of ABTS is also stronger than that of comparative example 1 ( Figure 3 ).

[0117] From the above examples, it can be seen that in terms of starch digestibility (Table 3), the addition of goat milk and sourdough has a positive effect on the digestible starch part of bread, and the starch digestion rate is significantly slowed down, that is, RDS is significantly reduced, and SDS and RS are increased to a certain extent. Examples 5 and 6 have lower eGI (64.07 / 62.58), making high GI (GI ≥ 70) bread become medium GI (56 ≤ GI ≤ 69) bread.

[0118] Table 1 is a table showing the basic characteristics of different whole wheat bread samples in the embodiment of the present invention and comparative example 1. Table 2 is a statistical table showing the volatile flavor substances of different whole wheat breads in the embodiment of the present invention and comparative example 1. Table 3 is a table showing the mold infection during storage of different whole wheat breads in the embodiment of the present invention and comparative example 1. Table 4 is a statistical table showing the total starch, fast digestible starch, slow digestible starch, resistant starch content, hydrolysis index and estimated glycemic index of different whole wheat breads in the embodiment of the present invention and comparative example 1.

[0119] Table 1: Basic characteristics of bread

[0120]

[0121] Table 2: Volatile flavor compounds of whole wheat bread

[0122]

[0123]

[0124]

[0125] Note: nd means not detected

[0126] Table 3: Fungal infection

[0127]

[0128] Note: Fungal infection: no obvious colonies (-), one colony (+), two colonies (++), three or more colonies (+++)

[0129] The total starch, fast-digestible starch, slow-digestible starch, resistant starch content, hydrolysis index and estimated glycemic index of the bread obtained in Examples 4 and 5 and Comparative Example 1 are shown in Table 4.

[0130] Table 4

[0131]

[0132] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention. Sequence Listing <110> South China University of Technology <120> Lactobacillus fermentum and its application in the preparation of whole wheat sour dough bread fortified with goat milk <160> 1 <170> SIPOSequenceListing 1.0 <210> 11 <211> 1477 <212> DNA / RNA <213> Limosilactobacillus fermentum M4 <400> 11 ggggcagggc ggtgctataa tgcagtcgac gcgttggccc aattgattga tggtgcttgc 60 acctgattga ttttggtcgc caacgagtgg cggacgggtg agtaacacgt aggtaacctg 120 cccagaagcg ggggacaaca tttggaaaca gatgctaata ccgcataaca acgttgttcg 180 catgaacaac gcttaaaaga tggcttctcg ctatcacttc tggatggacc tgcggtgcat 240 tagcttgttg gtggggtaac ggcctaccaa ggcgatgatg catagccgag ttgagagact 300 gatcggccac aatgggactg agacacggcc catactccta cgggaggcag cagtagggaa 360 tcttccacaa tgggcgcaag cctgatggag caacaccgcg tgagtgaaga agggtttcgg 420 ctcgtaaagc tctgttgtta aagaagaaca cgtatgagag taactgttca tacgttgacg 480 gtatttaacc agaaagtcac ggctaactac gtgccagcag ccgcggtaat acgtaggtgg 540 caagcgttat ccggatttat tgggcgtaaa gagagtgcag gcggttttct aagtctgatg 600 tgaaagcctt cggcttaacc ggagaagtgc atcggaaact ggataacttg agtgcagaag 660 agggtagtgg aactccatgt gtagcggtgg aatgcgtaga tatatggaag aacaccagtg 720 gcgaaggcgg ctacctggtc tgcaactgac gctgagactc gaaagcatgg gtagcgaaca 780 ggattagata ccctggtagt ccatgccgta aacgatgagt gctaggtgtt ggagggtttc 840 cgcccttcag tgccggagct aacgcattaa gcactccgcc tggggagagtac gaccgcaagg 900 ttgaaactca aaagaattga cggggcccg cacaagcggt ggagcatgtg gtttaattcg 960 aagctacgcg aagaacctta ccaggtcttg acatcttgcg ccaaccctag agatagggcg 1020 tttccttcgg gaacgcaatg acaggtggtg catggtcgtc gtcagctcgt gtcgtgagat 1080 gttgggttaa gtcccgcaac gagcgcaacc cttgttacta gttgccagca ttaagttggg 1140 cactctagtg agactgccgg tgacaaaccg gaggaaggtg gggacgacgt cagatcatca 1200 tgccccttat gacctgggct acacacgtgc tacaatggac ggtacaacga gtcgcgaact 1260 cgcgagggca agcaaatctc ttaaaaccgt tctcagttcg gactgcaggc tgcaactcgc 1320 ctgcacgaag tcggaatcgc tagtaatcgc ggatcagcat gccgcggtga atacgttccc 1380 gggccttgta cacaccgccc gtcacaccat gagagtttgt aacacccaaa gtcggtgggg 1440 taacctttta ggagccagcc gctaagtgac agatggt 1477

Claims

1. A fermented lactobacillus (Limosilactobacillus fermentum M4), characterized in that The deposit number is GDMCC 62472.

2. A method for preparing goat milk fortified whole wheat sour dough toast bread using the fermented lactobacillus according to claim 1, characterized in that The following steps are involved: 1) Activation of Lactobacillus fermentum: inoculate Lactobacillus fermentum M4 into the culture medium and activate it; the activation is that after inoculating Lactobacillus fermentum M4 into MRS liquid culture medium, incubate at 36-38°C for 16-18 h, then transfer to fresh MRS liquid culture medium, incubate for another 16-18 h, centrifuge and discard the supernatant; resuspend the bacterial sludge with sterile water and adjust the bacterial solution concentration to 1-3×10 9 CFU / mL; 2) Preparation of fermented sourdough by lactobacillus fermentum: dissolving activated lactobacillus fermentum M4 in water and diluting it to prepare an inoculum; mixing whole wheat flour and the inoculum to prepare whole wheat sourdough with a DY value of 166-200, stirring and mixing thoroughly, and culturing at a constant temperature of 36-38°C; in terms of mass parts, the whole wheat flour is 50-70 parts; the inoculum is 40-50 parts; 3) Preparation of bread dough: Mix instant active dry yeast, reconstituted goat milk and fermented lactobacillus sourdough; add whole wheat flour, white sugar and salt, stir and let rise; 4) Shaping: Take out the dough and let it rest, divide it into small doughs, roll it into toast shape, put it into toast box, and let it rise; 5) Baking: Bake the proofed toast-like dough to obtain goat milk fortified whole wheat sour dough toast bread.

3. The method for preparing goat milk fortified whole wheat sour dough toast bread according to claim 2, characterized in that: The fermented lactobacillus (Limosilactobacillus fermentum M4) is stored in a -80°C refrigerator.

4. The method for preparing goat milk fortified whole wheat sour dough toast bread according to claim 2, characterized in that: In step 2), the constant temperature culture time at 36-38°C is 12-18 h.

5. The method for preparing goat milk fortified whole wheat sour dough toast bread according to claim 2, characterized in that: In terms of weight, in step 3), the instant active dry yeast is 1.0-2.0 parts, the water-reconstituted goat milk is 1-69.7 parts, the fermented lactobacillus sourdough is 1-32 parts, the whole wheat flour is 75-100 parts, the white sugar is 2-5 parts, and the salt is 1-2 parts; step 3) also includes adding shortening in an amount of 1-5.0 parts, which is added after the whole wheat flour, the white sugar and the salt are added.

6. The method for preparing goat milk fortified whole wheat sour dough toast bread according to claim 5, characterized in that: Calculated by weight, the reconstituted goat milk is prepared by dissolving 1 part of pure raw goat milk powder in 6-8 parts of distilled water and sterilizing at 100-120° C. for 15-20 min.

7. The method for preparing goat milk fortified whole wheat sour dough toast bread according to claim 2, characterized in that: The proofing described in step 3) is to put the bread dough obtained after adding all the raw materials and stirring into a fermentation basin, seal it, and proof it in an incubator at 32-37°C for 40-70 minutes.

8. The method for preparing goat milk fortified whole wheat sour dough toast bread according to claim 2, characterized in that: In step 4), the small dough is covered with plastic wrap and then shaped, bubbles in the dough are squeezed out and then rolled into a toast shape and placed in a toast box; in step 4), the proofing is performed at 32-37° C. for 40-100 min.

9. The method for preparing goat milk fortified whole wheat sour dough toast bread according to claim 2, characterized in that: In step 5), the baking is carried out in a preheated oven, with the upper temperature being controlled at 190-220°C and the lower temperature being controlled at 210-220°C.

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