Dry lotus root starch as well as preparation method and application thereof

Abstract

The invention relates to the technical field of microorganisms, in particular to canna edulis powder and a preparation method and application thereof.The canna edulis powder is prepared through lactobacillus fermentation according to the characteristic that canna edulis powder is high in gelling property, amylose in the canna edulis powder is decomposed after lactic acid fermentation, so that the gelling property is effectively reduced, and the stability of the canna edulis powder is improved. The dry lotus root whole powder is produced by comparing lactic acid bacteria LMSSF3-1 which are automatically separated and screened by a selection research group through experiments and according to an innovative method of pulping and fermentation, the fermented dry lotus root powder has the advantages of high nutritional value, strong oxidation resistance, high protein content, low fiber content, good texture and remarkably reduced gel property through experiments, and meanwhile, the dry lotus root whole powder is used for preparing the meal replacement powder, so that the dry lotus root whole powder has the advantages of being high in nutritional value, high in oxidation resistance, high in protein content, low in fiber content, good in texture and low in gel property. Experiments prove that the meal replacement powder has a good probiotic effect and can well relieve colitis, the research and development of the meal replacement powder verify the possibility of the dry lotus root powder in food processing, the application range of the dry lotus root powder in food is widened, and the dry lotus root powder is excellent in quality.

Description

Technical Field

[0001] The present invention relates to the field of microbial technology, in particular to dry lotus root starch and a preparation method and application thereof. Background Art

[0002] Canna edulis (Ker Gawl.), also known as banana taro, beauty taro, canna, burnt taro, sweet potato, and champion potato, is a perennial monocotyledonous plant in the Cannaceae family. It prefers warmth and light, is highly resistant to stress, has strong adaptability, is high-yielding, and is easy to grow. It can be cultivated in subtropical regions with an average annual temperature above 15°C and an annual precipitation of over 800 mm. Its main production areas include Du'an, Dahua, Bama, and Mashan in Guangxi, as well as Yunnan, Guizhou, and Guangdong. Its rhizomes contain selenium, calcium, iron, and 17 amino acids, and are high in starch and cellulose. They are nutritious and easy to digest. Regular consumption benefits the brain and marrow, clears heat and moisturizes the lungs, and enhances beauty. It has preventive effects on digestive tract diseases, hypertension, cardiovascular and cerebrovascular diseases, and hemorrhoids. It is particularly effective in regulating gastrointestinal dampness and heat, and anorexia. Being all-natural and without side effects, it is considered a green and longevity food. Its rhizome is well-developed, branched and blocky; its stem is thick and can reach 3 meters in height. It is a good new source of starch.

[0003] At present, in the existing technology, most of the prepared lotus root starch is modified starch or cooked starch after the cellulose is removed, that is, the cellulose and other nutrients in the starch are low. Products such as vermicelli, starch sugar and meal replacement powder have been developed using lotus root starch as raw material. However, the amylose content in lotus root starch is high and easy to regenerate. The starch paste has a large viscosity and is easy to precipitate. The gel strength is high and it is easy to coagulate during food processing. These greatly limit its wide application in food systems. Moreover, there are no reports on lotus root powder in the existing technology. When we prepare the whole powder, the starch is not gelatinized, filtered, etc. The powder particles are relatively large and contain a large amount of fiber. The taste is not delicate enough. Therefore, how to improve the taste of lotus root powder and maximize the retention of lotus root powder fiber and other nutrients is a technical problem that requires in-depth research in the processing of lotus root powder. Summary of the Invention

[0004] In view of the above, it is necessary to provide a method for preparing lotus root powder that can improve the taste of lotus root powder and maximize the retention of fiber and other nutrients in the lotus root powder; at the same time, the application and possibility of the lotus root powder in the preparation of functional health foods are also studied.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] Dry lotus root powder, which is made by pulping dry lotus roots, fermenting with lactic acid bacteria, and drying; the lactic acid bacteria is the Lactobacillus plantarum strain LMSSF3-1, which is preserved in the General Microbiology Center of the China Culture Collection Administration, with the preservation number CGMCC NO.19874, address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing, and the preservation date is May 25, 2020.

[0007] The present invention also includes the use of the dry lotus root powder in preparing an antioxidant.

[0008] The present invention also includes a method for preparing the dry lotus root starch, which comprises the following steps:

[0009] (1) Select fresh lotus roots without rot or disease spots, clean them, peel them and slice them;

[0010] (2) Slicing the slices and mixing them with water, beating them into pulp, sterilizing them, inoculating them with lactic acid bacteria at a weight ratio of 2%, fermenting them, and then drying them to obtain dry lotus root powder;

[0011] The lactic acid bacteria is Lactobacillus paracasei strain LMSSF3-1, and its preservation number is CGMCC NO.19874.

[0012] Furthermore, the lotus root sliced ​​in step (1) is also subjected to a color protection treatment, wherein the color protection agent is citric acid and / or orange peel water.

[0013] Furthermore, the mass percentage of the citric acid is 0.8%, and the volume percentage of the orange peel water is 10%.

[0014] Furthermore, the preparation method of the orange peel water is: mixing dried orange peel and water in a solid-liquid ratio of 2:1, boiling for 10 minutes, filtering, and blending with sterile water according to the volume percentage.

[0015] Furthermore, the volume ratio of the citric acid to the orange peel water is 1:1.

[0016] The present invention also includes the use of the dry lotus root powder in preparing dry lotus root meal replacement powder, which is composed of the following ingredients in percentage by weight: 25% of dry lotus root powder, 10% of water chestnut powder, 15% of oatmeal, 10% of yam powder, 10% of oligofructose, 10% of freeze-dried apple pieces, 7% of inulin, 5% of whey protein, 5% of strawberry pieces and 3% of citrus fiber.

[0017] The present invention also includes the use of the meal replacement powder in alleviating colitis.

[0018] The present invention also includes the use of the meal replacement powder in enriching the types of intestinal probiotics.

[0019] The present invention has the following beneficial effects:

[0020] 1. The present invention aims at the characteristic of strong gelling property of dry lotus root powder and utilizes lactic acid bacteria fermentation to prepare dry lotus root powder. After lactic acid fermentation, the amylose in the dry lotus root powder is decomposed, thereby effectively reducing the gelling property. In addition, when selecting lactic acid bacteria, we conducted detailed selection and comparison of strains and preparation methods, and obtained an innovative method of beating + fermentation. The selected lactic acid bacteria LMSSF3-1 is the lactic acid bacteria LMSSF3-1 screened by the applicant's research group. The lactic acid bacteria can effectively colonize in the dry lotus root powder and show good fermentation ability. The fermented dry lotus root powder has high nutritional value, strong antioxidant, high protein content, low fiber content, good texture, and significantly reduced gelling property, which effectively improves the application range of dry lotus root powder in food. It is a dry lotus root powder with excellent quality.

[0021] 2. After reasonable formulation, the lotus root meal replacement powder of this application has good prebiotic and health-care functions, which are specifically manifested as: it can repair damaged colon structure and can be used as a functional food to improve colon damage caused by acute enteritis; in addition, the meal replacement powder also has good prebiotic functions, can promote the growth of probiotics in the intestines of mice, and enrich the intestinal flora. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a state diagram of the dry lotus root powder prepared by method 1 after 24 hours of fermentation; in the figure, Figure A is the fermented whole powder inoculated with strain LMSSF3-1, and Figure B is the fermented whole powder inoculated with strain LLZB2-2.

[0023] Figure 2 This is a state diagram of the dry lotus root powder prepared by method 2 after fermentation for 24 hours; in the figure, Figure A is the fermented whole powder inoculated with strain LMSSF3-1, and Figure B is the fermented whole powder inoculated with strain LLZB2-2.

[0024] Figure 3 The diagrams are the organizational status diagrams of fermentation by method one and method two; in the diagram, Figure A is the fermentation organizational status of method one, and Figure B is the fermentation organizational status of method two.

[0025] Figure 4 This is a diagram of the fermentation tissue state of method 1 without sterilization treatment; in the figure, Figure A is the fermentation whole powder of the inoculated strain LMSSF3-1, and Figure B is the fermentation whole powder of the inoculated strain LLZB2-2.

[0026] Figure 5 This is a diagram of the fermentation tissue state of method 2 without sterilization treatment; in the figure, Figure A is the fermentation whole powder of the inoculated strain LMSSF3-1, and Figure B is the fermentation whole powder of the inoculated strain LLZB2-2.

[0027] Figure 6 This is the effect of lotus root meal replacement powder on growth and intestinal tissue; in the figure, A is the change in mouse weight, B is the change in mouse food intake, C is the change in mouse weight, D is the change in mouse food intake, and E is the disease score index experimental diagram; F is the colon anatomy diagram; G is the experimental diagram of colon length in a healthy model; H is the experimental diagram of colon length in a colitis model; I is the H&E staining diagram of colon tissue.

[0028] Figure 7 This is the effect of lotus root meal replacement powder on the concentration of antioxidant enzymes and inflammatory factors in mouse serum; in the figure, A and E are the experimental results of SOD concentration in serum, B and F are the experimental results of GSH concentration in serum, C and G are the experimental results of MDA concentration in serum, D and H are the experimental results of MPO concentration in serum, I is the experimental results of TNF-α concentration in serum, J is the experimental results of INF-γ concentration in serum, K is the experimental results of IL-1β concentration in serum, and L is the experimental results of IL-6 concentration in serum.

[0029] Figure 8 To investigate the effect of lotus root meal replacement powder on the diversity of intestinal flora in mice.

[0030] Figure 9 This study aimed to investigate the effect of lotus root meal replacement powder on the production of major short-chain fatty acids in mouse feces.

[0031] Biomaterial deposit information

[0032] The strain information deposited in this application is as follows: The deposit number of Lactobacillus plantarum strain LMSSF3-1 is CGMCC NO.19874. The strain is deposited in the General Microbiology Center of China Culture Collection Administration, address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing. The deposit date is May 25, 2020. The strain is a public strain and has been disclosed in patent CN118006501A.

[0033] The preservation number of Lactobacillus plantarum strain LLZB2-2 is CGMCCNO.19875. The strain is deposited in the General Microbiology Center of China Culture Collection Administration, address: No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing. The preservation date is May 25, 2020. The strain is a public strain and has been disclosed in patent CN112314824A. DETAILED DESCRIPTION

[0034] All features disclosed in this specification, or all steps in the disclosed methods or processes, except mutually exclusive features and / or steps, can be combined in any manner.

[0035] Any feature disclosed in this specification (including any accompanying claims and abstract), unless otherwise stated, is merely one example of a series of equivalent or similar features.

[0036] Example 1

[0037] This embodiment is a method for preparing dry lotus root powder, and the specific process is as follows:

[0038] 1. Crushing method:

[0039] 1. Choose fresh lotus roots without rot or disease spots, clean them, peel them and slice them;

[0040] 2. After slicing, soak the lotus root slices in a color preservative for color protection, wherein the color preservative is a Vc aqueous solution;

[0041] 3. After protecting the color, drying and crushing to obtain dry lotus root powder;

[0042] 4. Sterilize the crushed lotus root powder at 120°C for 20 minutes, then mix it with sterile water at a solid-liquid ratio of 1:10. After mixing, inoculate lactic acid bacteria at a weight ratio of 2% (w / w) and ferment it at 36°C for 24 hours. Take samples at the end of fermentation for sensory evaluation and sample drying to obtain lotus root powder.

[0043] Control: No sterilization treatment.

[0044] 2. Beating method:

[0045] 1. Choose fresh lotus roots without rot or disease spots, clean them, peel them and slice them;

[0046] 2. After slicing, mix with water at a solid-liquid ratio of 1:5, beat and sterilize at 120°C for 20 minutes, then inoculate with lactic acid bacteria at a weight ratio of 2% (w / w) and ferment at 36°C for 24 hours. At the end of fermentation, take samples for sensory evaluation and sample drying to obtain dry lotus root powder.

[0047] Control: No sterilization treatment.

[0048] The lactic acid bacteria inoculated in step 4 of method 1 and step 2 of method 2 were strain LMSSF3-1 and strain LLZB2-2;

[0049] When using method 1 to prepare dry lotus root powder, the state after fermentation for 24 hours is as follows: Figure 1 As shown, Figure 1Middle: Figure A shows the whole meal fermented with strain LMSSF3-1, and Figure B shows the whole meal fermented with strain LLZB2-2. As can be seen in the figures, the whole meal fermented with strain LMSSF3-1 is darker in color, while the whole meal fermented with strain LLZB2-2 is orange-yellow. However, after centrifugation, the supernatant is essentially the same color, though darker. The texture of both is similarly fine, and the whole meal particles can be seen. The aroma of LMSSF3-1 is a mixture of mung beans and caramel, with a slightly sour taste; the aroma of LLZB2-2 is caramel, with a less pronounced sour taste.

[0050] When using method 2 to prepare dry lotus root powder, the state after fermentation for 24 hours is as follows: Figure 2 As shown, Figure 2 Middle: Figure A shows the fermented whole meal inoculated with strain LMSSF3-1, and Figure B shows the fermented whole meal inoculated with strain LLZB2-2. As can be seen in the figures, LMSSF3-1 and LLZB2-2 are similar in color, being whitish with a predominantly light yellow hue similar to that of lotus root. After centrifugation, the supernatant is relatively clear. Texture-wise, both have a similarly smooth texture, with distinct starch gelatinization. In terms of aroma, LMSSF3-1 has a mung bean aroma and is slightly sour. LLZB2-2 has a weaker mung bean aroma and a distinct fermented flavor, making it less palatable than LMSSF3-1.

[0051] The tissue state of fermentation of method 1 and method 2 is as follows Figure 3 As shown: Figure 3 Figure A shows the fermentation texture of Method 1, and Figure B shows the fermentation texture of Method 2. As can be seen from the figures, the texture of the fermented lotus root after pulping and sterilization is more pronounced, and the stratification is much less pronounced than when fermented with whole lotus root powder. In terms of color, the fermented lotus root after sterilization is brighter and more yellow, and there is also a certain difference in smell.

[0052] The status of the fermentation tissue using method 1 without sterilization (control) is as follows Figure 4 As shown, Figure 4 Middle: Figure A shows whole meal fermented with strain LMSSF3-1, and Figure B shows whole meal fermented with strain LLZB2-2. As can be seen from the figures, the fermented whole meal without sterilization also exhibits significant stratification, with the supernatant being more turbid than the sterilized one, and exhibiting a distinct graininess. The two are similar in color, with the sterilized one showing a brighter yellow. LMSSF3-1 has a grain-like aroma, similar to rice bran, with a hint of tofu, and a less pronounced sourness. LLZB2-2 is similar.

[0053] The status of the fermentation tissue using method 2 without sterilization (control) is as follows Figure 5 As shown, Figure 5Middle: Figure A shows the fermented whole meal from the inoculation of strain LMSSF3-1, and Figure B shows the fermented whole meal from the inoculation of strain LLZB2-2. As shown in the figures, the state of the non-sterilized lotus root pulp fermented for 24 hours after pulping is similar, with a noticeable gelatinization. LLZB2-2 has a sweet aroma similar to the greenness of straw, while LMSSF3-1 produces a mung bean aroma with a more pronounced sour taste than the sterilized pulp. The two pulps are similar in color, but the sterilized pulp is brighter yellow.

[0054] Therefore, combined with sensory observation, we believe that the appearance and smell of the dried lotus root powder fermented by method 2 are better, so we focus on further improving this process. From the perspective of fermentation effect, the flavor produced by the strain LMSSF3-1 is better.

[0055] Example 2:

[0056] This example studies the properties of fermented lotus root powder according to method 2, with the unfermented lotus root powder that was directly pulped and then dried serving as the control group.

[0057] 1. The physical and chemical indicators of dry lotus root powder, the specific test indicators are: moisture, crude ash, crude protein, crude fat and crude fiber. The results are shown in Table 1:

[0058] Table 1 Physical and chemical indicators of lotus root powder

[0059]

[0060] Note: Different lowercase letters in the table represent significant differences in the same column (P<0.05); the same below.

[0061] As shown in Table 1, there were no significant differences in moisture content among the three groups of dry lotus root flour. The tests for each component were accurate, with moisture having a small impact. The test results showed that after fermentation with the strains, the crude ash content of the dry lotus root flour decreased, with strain LMSSF3-1 having the lowest crude ash content, followed by strain LLZB2-2, with significant differences. Both groups were significantly lower than the unfermented experimental group. The crude protein content of strain LMSSF3-1 was significantly higher than that of the strain LLZB2-2 experimental group and the unfermented control group. There was little difference in crude fat content. There was no significant difference in crude fiber content between strains LMSSF3-1 and LLZB2-2, but both groups were significantly lower than the unfermented experimental group. This suggests that the addition of the strains promoted the decomposition of dry lotus root, resulting in a decrease in crude ash content, an increase in crude protein content, and a decrease in crude fiber content. The fermentation results indicate that strain LMSSF3-1 exhibited superior fermentation efficiency to strain LLZB2-2.

[0062] 2. Determine the antioxidant activity of lotus root powder. The specific test method is as follows: weigh 10g lotus root powder and mix it with water at a solid-liquid ratio of 1:1, stir it thoroughly, let it stand for 24 hours, and then absorb the supernatant to measure the DPPH free radical scavenging rate at a wavelength of 517nm. The specific test method is shown in Table 2:

[0063] Table 2 Antioxidant properties of lotus root starch

[0064]

[0065] As shown in Table 2, the dry lotus root powder prepared by fermentation of strain LMSSF3-1 can significantly improve the antioxidant activity of dry lotus root powder.

[0066] 3. Determine light transmittance:

[0067] A 1.0% suspension of lotus root starch was heated in a boiling water bath for 15 minutes, cooled at room temperature for 30 minutes, and then the absorbance was measured at 650 nm using distilled water as a blank. See Table 3 for details:

[0068] Table 3 Transmittance of dry lotus root starch

[0069]

[0070] As can be seen from Table 3, the transmittance of dry lotus root powder will slowly increase with the increase of time. From the perspective of the increase, after 1 hour, the transmittance of each group of dry lotus root powder reaches a stable state with no obvious change; from the perspective of the size of the transmittance: the fermentation experimental group of strain LMSSF3-1> the fermentation experimental group of strain LLZB2-2> the unfermented control group, which shows that after adding lactic acid bacteria for fermentation, the homogenization is more thorough, the impurities are less, and the transmittance of the whole dry lotus root powder can be significantly improved.

[0071] 4. Determination of texture characteristics:

[0072] A 10% suspension of lotus root starch was heated in a boiling water bath for 20 minutes, poured into a square rubber mold, cooled to room temperature, and stored at 4°C for 24 hours before measuring texture properties. Test conditions: TPA cycle mode, TA5 probe, pre-test speed 1.00 mm / s, test speed 1.00 mm / s, return speed 1.00 mm / s. See Table 4 for details:

[0073] Table 4 Texture of lotus root starch

[0074]

[0075] As shown in Table 4, the addition of lactic acid bacteria can significantly reduce the hardness, elasticity, cohesion, chewiness and adhesiveness of lotus root starch. From the perspective of the reduction effect, the reduction effect of strain LMSSF3-1 fermentation is more significant than that of strain LLZB2-2 fermentation. This is because the lactic acid fermentation process will produce lactic acid, and a certain amount of acid will promote the hydrolysis of amylose.

[0076] Example 3

[0077] This embodiment is an improvement to the second method, and is specifically as follows:

[0078] In the process of preparing the whole lotus root powder, we considered adding a color preservative to improve the quality of the whole lotus root powder, and made the following improvements to the preparation method:

[0079] 1. Choose fresh lotus roots without rot or disease spots, clean them, peel them and slice them;

[0080] 2. After slicing, add color-protecting solution and soak for 2 hours;

[0081] 3. After color protection, mix with water at a solid-liquid ratio of 1:5, beat and sterilize at 120°C for 20 minutes, then inoculate lactic acid bacteria (strain LMSSF3-1) at a weight ratio of 2% (w / w) and ferment at 36°C for 24 hours. Take samples at the end of fermentation for sensory evaluation and sample drying to obtain dry lotus root powder.

[0082] Color preservatives selected: 0.8% by mass of citric acid, 0.8% by mass of VC and 10% by volume of orange peel water.

[0083] The orange peel water is prepared by mixing dried orange peels and water in a solid-to-liquid ratio of 2:1, boiling for 10 minutes, and filtering. When used, the mixture is blended with sterile water in a volume percentage ratio.

[0084] The whole lotus root powder prepared with different color preservatives was tested, and it was found that the color preservative had the most obvious effect on the transmittance of the lotus root powder, as shown in Table 5:

[0085] Table 5 Transmittance of lotus root starch with different color preservatives

[0086]

[0087] From the comparison of the strain LMSSF3-1 fermentation experimental group in Table 5 and Table 3 of Example 2, it can be seen that citric acid and orange peel water color preservatives have a certain effect on improving the transmittance of dry lotus root powder, but the effect is not very obvious. VC color preservative will cause the transmittance of dry lotus root powder to decrease slightly, and the decrease effect is not obvious. Combined with the above conditions, citric acid and orange peel water are preferably mixed to further study the effects of these two color preservatives on the transmittance of dry lotus root powder, specifically:

[0088] Citric acid was prepared to have a mass percentage of 0.8%, and orange peel water was prepared to have a volume percentage of 10%. Then, the two were mixed at volume ratios of 1:3, 1:2, 1:1, 2:1, and 3:1 to prepare dry lotus root starch. The light transmittance of the dry lotus root starch was measured. The results are shown in Table 6:

[0089] Table 6 Transmittance of lotus root starch prepared with different ratios of color preservatives

[0090]

[0091] As shown in Table 6, when the volume ratio of citric acid to orange peel water is 1:1, the transmittance of lotus root starch is significantly improved. The improvement effects of other experimental groups are not much different from that of the strain LMSSF3-1 fermentation experimental group. Therefore, a volume ratio of citric acid to orange peel water of 1:1 is preferred as the color preservative in the optimized solution.

[0092] In summary, combined with Examples 1-3, we concluded that the best processing method for dry lotus root powder is:

[0093] 1. Choose fresh lotus roots without rot or disease spots, clean them, peel them and slice them;

[0094] 2. After slicing, add the slices into a color-protecting solution and soak for 2 hours; the color-protecting agent is prepared by mixing citric acid and orange peel water in a volume ratio of 1:1, with the mass percentage of citric acid being 0.8% and the volume percentage of orange peel water being 10%. The preparation method of the orange peel water is as follows: mixing dried orange peel and water in a solid-liquid ratio of 2:1, boiling for 10 minutes, filtering, and blending with sterile water in the aforementioned volume percentage.

[0095] 3. After color protection, mix with water at a solid-liquid ratio of 1:5, beat and sterilize at 120°C for 20 minutes, then inoculate lactic acid bacteria (strain LMSSF3-1) at a weight ratio of 2% (w / w) and ferment at 36°C for 24 hours. Take samples at the end of fermentation for sensory evaluation and sample drying to obtain dry lotus root powder.

[0096] In summary, the present application uses a lactic acid bacteria fermentation method to prepare dry lotus root powder. The prepared whole powder has high nutritional value, strong antioxidant, high protein content, low fiber content, good texture, and significantly reduced gelation. It effectively improves the application range of dry lotus root powder in food and is a high-quality dry lotus root powder.

[0097] Example 4

[0098] The research team used the whole lotus root powder prepared in Example 3 to prepare a probiotic meal replacement powder, as follows:

[0099] 1. Development of meal replacement powder formula: Referring to the energy value recommended by the "Dietary Guidelines for Chinese Residents 2022 Edition" and the energy supply ratio of protein, fat and carbohydrates, the formula of dry lotus root meal replacement powder was designed. Based on the previous meal replacement powder formula development and multiple sensory evaluations of the research team, it was determined that the addition amount of dry lotus root powder is ≤25%, which does not affect the flavor and solubility of the meal replacement powder, while maintaining a delicate and smooth taste. The dry lotus root meal replacement powder is made by mixing 25% dry lotus root powder, 10% water chestnut powder, 15% oatmeal, 10% yam powder, 10% oligofructose, 10% freeze-dried apple pieces, 7% inulin, 5% whey protein, 5% strawberry pieces and 3% citrus fiber. Except for the dry lotus root powder, which is processed by itself, the other raw materials are purchased from Xinghua Green Shuai Food Co., Ltd., Pingle County Leyao Food Co., Ltd., and Shaanxi Yuanbeibei Biotechnology Co., Ltd.

[0100] 2. Animal rearing conditions, modeling and grouping:

[0101] (1) Healthy mice: The animals were housed in a standard environment with a temperature of 23±1°C, a humidity of 40-60%, and a 12-hour light / dark cycle. After one week of adaptive feeding, 48 C57BL / 6J mice were randomly divided into four groups, each with 12 mice, and a control group (ND group, basal feed), a positive control group (DF, dietary fiber + basal feed), a low-dose meal replacement powder group (LCEK group, basal feed containing 1 / 3 dry lotus root meal replacement powder), and a high-dose meal replacement powder group (HCEK group, basal feed containing 2 / 3 dry lotus root meal replacement powder). The intervention experiment lasted for 4 weeks. The mice were housed in separate cages in the same room, with 6 mice in each cage, and had free access to water and food.

[0102] (2) Colitis mice: The animals were housed in a standard environment with a temperature of 23±1°C, a humidity of 40-60%, and a 12-hour light / dark cycle. After one week of adaptive feeding, 12 C57BL / 6J mice were randomly selected as the negative control group (Control) and drank drinking water without DSS. The remaining mice were used as the colitis model group and drank drinking water containing 2% (wt / vol) DSS. The mice lost more than 5% of their blank body weight to successfully establish the artificial model. 48 model mice were screened and randomly divided into 4 groups, each with 12 mice, namely the colitis group (DSS group, basic feed), the positive control group (DSASP group, basic feed + oral administration of 200 mg / kg / day sulfasalazine), the low-dose meal replacement powder group (DLCEK group, basic feed containing 1 / 3 dry lotus root meal replacement powder), and the high-dose meal replacement powder group (DHCEK group, basic feed containing 2 / 3 dry lotus root meal replacement powder). The intervention experiment lasted for 5 days. The mice were housed in separate cages in the same room, with 6 mice in each cage, and had free access to water and food.

[0103] 3. Index measurement method

[0104] (1) Disease Activity Index (DAI) Determination: The disease activity index (DAI) was used for evaluation (see Table 7). Weight loss was calculated as the percentage difference between the initial body weight (day 0) and the body weight on the last day of the experiment.

[0105] Table 7 Evaluation of Disease Activity Index (DAI)

[0106]

[0107] (2) Histological analysis: After the experiment, the colon length of each mouse was recorded and compared between different groups. The distal colon tissue was embedded in paraffin and sliced ​​with a thickness of 4-10 μm. The sections were dewaxed and stained with hematoxylin-eosin (H&E). Subsequently, the sections were subjected to histological examination and imaging analysis using an OLYMPUS BX53F2 microscope (Olympus, Japan).

[0108] (3) Enzyme-linked immunosorbent assay (ELISA): The levels of inflammatory markers TNF-α, IL-1β, and IL-6, as well as oxidative stress-related indicators MDA, MPO, SOD, and GSH in serum samples were detected using commercial ELISA kits (Jiangsu Meiman Industrial Co., Ltd., Jiangsu, China).

[0109] (4) DNA extraction and 16S rRNA gene sequencing: using EZNA Total intestinal microbial DNA was extracted from fecal samples using a soil DNA extraction kit (OmegaBio-tek, Norcross, GA, USA), and DNA quality was assessed by 1% agarose gel electrophoresis. Subsequently, DNA samples were sent to Jiangsu Sanshu Biotechnology Co., Ltd. (Jiangsu, China) for 16S rRNA amplicon sequencing analysis.

[0110] (5) Short-chain fatty acids (SCFAs) analysis: The content of short-chain fatty acids in fecal tissues was determined by gas chromatography-mass spectrometry (GC-MS, Agilent 7820, Agilent Technologies, USA) and quantified relative to acetic acid, propionic acid, isobutyric acid, butyric acid, isovaleric acid, valeric acid, hexanoic acid, and 4-methylvaleric acid (Sigma-Aldrich).

[0111] 4. Experimental results:

[0112] The abbreviations in the following experimental figures refer to: healthy mouse model: ND-control group (basic feed), DF-positive control group (dietary fiber + basic feed), LCEK-low-dose meal replacement powder group (basic feed containing 1 / 3 dry lotus root meal replacement powder), HCEK-high-dose meal replacement powder group (basic feed containing 2 / 3 dry lotus root meal replacement powder); enteritis mouse model: Control-negative control group (drinking water without DSS), DSS-enteritis group (basic feed), DSASP-positive control group (basic feed + gavage of 200 mg / kg / day sulfasalazine), DLCEK-low-dose meal replacement powder group (basic feed containing 1 / 3 dry lotus root meal replacement powder), DHCEK-high-dose meal replacement powder group (basic feed containing 2 / 3 dry lotus root meal replacement powder).

[0113] (1) Effects of lotus root meal replacement powder on growth and intestinal tissue Figure 6 As shown: In healthy mice, the body weight and food intake of mice fed with diet supplemented with meal replacement powder were higher than those of the ND untreated group and the DF (dietary fiber) group ( Figure 6 A, 6B). Adding dietary fiber and lotus root meal replacement powder to feed can significantly increase colon length, and the greater the amount of lotus root meal replacement powder added, the longer the colon length ( Figure 6 F, 6G). In the DSS-induced colitis model, mice showed significant weight loss and reduced feed intake after DSS feeding, while mice treated with lotus root meal replacement powder or sulfasalazine (SASP) showed a significant slowing of weight loss compared with mice with DSS-induced colitis ( Figure 6 C). At the same time, compared with the DSS-treated group, the feed intake of the group treated with dry lotus root meal replacement powder or SASP was significantly increased ( Figure 6 DSS-induced colitis resulted in a significant reduction in colon length, but treatment with lotus root meal replacement powder or SASP significantly improved this condition ( Figure 6 F, 6H). At the end of the experiment, DAI in DSS-treated mice was significantly increased compared with the control group, while DSASP, DLCEK, and DHCEK effectively prevented the changes in DAI levels ( Figure 6 E). H&E staining of the collected distal colon tissue revealed that colon tissue sections from the DSS-treated group showed severe degeneration and necrosis of intestinal mucosal epithelial cells, accompanied by a large number of inflammatory cell infiltrations. In contrast, intervention with DSASP, DLCEK, and DHCEK effectively protected the colon structure, with only slight degeneration and necrosis of local intestinal mucosal epithelial cells and very few inflammatory cell infiltrations ( Figure 6 I).

[0114] (2) Effects of lotus root meal replacement powder on serum antioxidant enzyme concentrations and inflammatory factors in mice Figure 7As shown: After healthy mice were fed with high-dose lotus root meal replacement powder, the serum SOD and GSH concentrations were significantly higher than those in the ND group (p < 0.05), while the serum MDA concentration was significantly lower than that in the ND group (p < 0.05), and there was no significant effect on the MPO concentration (p > 0.05) ( Figure 7 A, 7B, 7C, 7D). Serum SOD and GSH levels in mice with DSS colitis were significantly decreased (p < 0.001). In contrast, MDA and MPO concentrations were significantly increased (p < 0.001). Dry lotus root meal replacement powder increased serum SOD and GSH levels in mice with colitis (p < 0.001). Compared with the DSS group, dry lotus root meal replacement powder inhibited MDA and MPO contents (p < 0.001). Figure 7 E, 7F, 7G, 7H). In DSS-induced colitis, the expression levels of TNF-α, IL-1β, and IL-6 were significantly increased compared with the control group (p < 0.001) ( Figure 7 I, 7J, 7K). After intervention with the dry lotus root meal replacement powder, compared with the DSS group, the dry lotus root meal replacement powder significantly reduced the production of TNF-α (p < 0.05); similarly, the dry lotus root meal replacement powder also reduced the concentrations of IL-1β and IL-6.

[0115] (3) Effects of lotus root meal replacement powder on intestinal flora of mice Figure 8 As shown: By detecting the changes in the intestinal flora of mice, it was further verified that the dry lotus root meal replacement powder can promote the health of normal mice and alleviate the adverse effects of DSS. In healthy mice, the abundance of intestinal flora was increased in both the DF group and the LCEK group, and the α diversity of the intestinal flora of mice was significantly reduced ( Figure 8 A); After the adaptation period to the end of the modeling period, the α diversity of the mouse intestinal flora tended to converge, indicating that the DSS colitis model is effective ( Figure 8 B, 8C, 8F, 8G); After mice were induced with DSS enteritis, the intake of lotus root meal replacement powder promoted the intestinal flora of mice to a healthy level, and the lotus root meal replacement powder intake group showed significant improvement compared with the positive control (DSASP) ( Figure 8 D, 8H). In the early and late stages of DSS modeling, the changes in intestinal flora diversity were not significant ( Figure 8 J, 8K), on the contrary, in the DSS-induced colitis mice group, after intervention with high-dose and low-dose lotus root meal replacement powder, the control group (Control), lotus root meal replacement powder intervention groups (DLCEK, DHCEK), DSS-induced colitis group (DSS) and DSS positive control group (DSASP) all showed significant differences ( Figure 8 L), indicating that at the end of the intervention, the dry lotus root meal replacement powder significantly changed the structure and composition of the mouse intestinal microorganisms.

[0116] (4) Effects of lotus root meal replacement powder on the production of major short-chain fatty acids in mouse feces Figure 9 As shown in the figure: In the healthy mouse model, compared with the ND group, the total SCFAs content in the DF, LCEK and HCEK groups increased by 1.62, 1.12 and 1.56 times, respectively, and the changes were statistically significant. Among them, the acetic acid and propionic acid content in the DF group and the acetic acid content in the HCEK group were significantly increased ( Figure 9 A). In the colitis mouse experiment, the total SCFAs content in the feces of untreated DSS-induced colitis mice was significantly reduced compared with the control group. After 5 days of treatment with SASP and lotus root meal replacement powder, the total SCFAs content in the feces of mice in the DSASP, DLCEK and DHCEK groups was significantly increased compared with the control group and DSS. Compared with the DSS group, the total SCFAs content in the DSASP group, DLCEK group and DHCEK group increased by 1.23 times, 1.61 times and 1.49 times, respectively, and the changes were statistically significant. Among them, the acetic acid, propionic acid and butyric acid contents in the DSASP group, DLCEK group and DHCEK group were significantly increased ( Figure 9 B).

[0117] In summary, after reasonable formulation, the lotus root meal replacement powder of the present application can improve the antioxidant capacity of mice, increase the diversity of intestinal probiotics, and has good prebiotic functions; in addition, the meal replacement powder can also repair damaged colon structure, help the intestinal flora imbalance caused by colitis to return to a healthy state, reduce the level of inflammatory factors in the body, and can be used as a functional food to improve colon damage caused by acute enteritis.

[0118] The above-described embodiments merely illustrate several embodiments of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. Dry lotus root powder, characterized in that: The lotus root powder is prepared by pulping lotus roots, fermenting with lactic acid bacteria and drying; the lactic acid bacteria is the Lactobacillus plantarum strain LMSSF3-1, and its preservation number is CGMCCNO.19874.

2. Use of the dry lotus root powder as claimed in claim 1 in the preparation of antioxidants.

3. A method for preparing the dry lotus root powder as claimed in claim 1, characterized in that: The method comprises the following steps: (1) Select fresh lotus roots without rot or disease spots, clean them, peel them and slice them; (2) Slicing the slices and mixing them with water, beating them, sterilizing them, inoculating them with lactic acid bacteria at a weight ratio of 2%, fermenting them, and then drying them to obtain dry lotus root powder; The lactic acid bacteria is Lactobacillus plantarum strain LMSSF3-1, and its preservation number is CGMCC NO.19874.

4. The method according to claim 3, characterized in that The lotus root sliced ​​in step (1) is also subjected to a color protection treatment, wherein the color protection agent is citric acid and / or orange peel water.

5. The method according to claim 4, characterized in that The mass percentage of the citric acid is 0.8%, and the volume percentage of the orange peel water is 10%.

6. The method according to claim 4, characterized in that The preparation method of the orange peel water is as follows: sun-dried orange peel and water are mixed in a solid-liquid ratio of 2:1, then boiled for 10 minutes, filtered, and blended with sterile water in the volume percentage.

7. The method according to claim 4, characterized in that The volume ratio of the citric acid to the orange peel water is 1:

1.

8. The use of the lotus root powder as claimed in claim 1 in preparing lotus root meal replacement powder, characterized in that: The lotus root meal replacement powder is composed of the following ingredients in percentage by weight: 25% lotus root powder, 15% oatmeal, 10% water chestnut powder, 10% yam powder, 10% oligofructose, 10% freeze-dried apple particles, 7% inulin, 5% whey protein, 5% strawberry particles and 3% citrus fiber.

9. Use of the meal replacement powder as claimed in claim 8 in alleviating colitis.

10. Use of the meal replacement powder according to claim 8 in promoting the diversity of intestinal probiotics.

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