Method for preparing fermentation liquor rich in organic acid from garlic syrup

Abstract

The invention relates to the technical field of biological feed preparation, in particular to a method for preparing fermentation liquor rich in organic acid from garlic syrup. According to the method disclosed by the invention, the dominant flora obtained by self-fermentation of the garlic syrup is adopted for fermentation of the organic acid, the garlic syrup containing garlic oil or allicin can be used as a fermentation raw material of the organic acid, allicin removal treatment does not need to be carried out on the raw material, and the preparation process of the organic acid is simplified; the viable count of the fermentation seed solution enriched by the method is high, and higher saccharide conversion efficiency can be realized; the fermentation liquor prepared by the method has higher organic acid content, and the garlic syrup can be processed into a valuable organic acid compound, so that resource utilization is realized.

Description

Technical Field

[0001] The invention relates to the technical field of biological feed preparation, in particular to a method for preparing organic acid-rich fermentation liquid by utilizing garlic syrup. Background Art

[0002] Garlic (Allium sativum L.) is an underground bulb of the genus Allium in the Liliaceae family. It has a strong spicy taste. Garlic heads, garlic sprouts and garlic mosses can be eaten as vegetables and seasonings, and can also be used as medicine. It is a widely used medicinal and edible plant. Garlic is rich in protein, carbohydrates, sulfur-containing compounds, bioactive enzymes and other substances. It has a variety of physiological and pharmacological effects, such as anti-oxidation, free radical scavenging, blood lipid lowering, anti-tumor, anti-pathogenic microorganisms, improving blood circulation, relieving fatigue, etc. Long-term consumption can play a role in disease prevention and health care.

[0003] At present, there are few types of primary processed garlic products, mainly sweet and sour garlic, black garlic, garlic powder, garlic slices, etc. Among the existing garlic products, the unique spicy and irritating smell of garlic limits its wide application as food and food ingredients. Using microbial strains to ferment garlic or its processing by-products to prepare fermented products can enrich nutrients and reduce spicy and irritating smells, which is also an important direction for garlic processing in the future. However, garlic and its processing by-products contain allicin. Since allicin has antibacterial properties, it must be removed before fermentation, otherwise it is likely to inhibit the growth of fermented strains, and removing allicin will inevitably increase the pretreatment cost of raw materials, which is not conducive to large-scale industrial production. In addition, there are problems such as poor screening of fermented strains and application effects in the preparation of garlic-related fermented products.

[0004] Garlic slice processing wastewater is the wastewater discharged during the production of garlic slices. The preparation process of garlic slices mainly includes stone removal, peeling and stem removal, cleaning, slicing, rinsing, dehydration, etc. A large amount of organic wastewater will be generated during the rinsing and centrifugal dehydration process. The main components of this organic wastewater are polysaccharides and proteins, and it also contains allicin. At present, there is no effective resource utilization method for garlic slice processing wastewater. Summary of the invention

[0005] The invention provides a method for preparing a fermentation liquid rich in organic acid by utilizing garlic syrup.

[0006] In order to solve the problem of resource utilization of garlic processing byproducts, the present invention has developed a method for preparing a fermentation liquid rich in organic acids using garlic syrup. During the research and development process, the present invention found that garlic syrup still contains a certain amount of allicin. When the fermentation strain is directly inoculated to ferment the garlic syrup, the allicin therein will have a significant inhibitory effect on the fermentation strain, resulting in fermentation failure, low organic acid production or a long fermentation cycle. The present invention unexpectedly found that aerobic fermentation and anaerobic fermentation of garlic syrup can effectively promote the proliferation of characteristic flora adapted to garlic syrup, obtain garlic syrup characteristic flora, and use the characteristic flora as fermentation seeds to inoculate garlic syrup for anaerobic fermentation, which can efficiently convert organic matter such as sugars in garlic syrup into organic acids, thereby obtaining a fermentation liquid rich in organic acids.

[0007] Specifically, the present invention provides the technical solution described below.

[0008] The present invention provides a method for preparing a fermentation liquid rich in organic acid by using garlic syrup, the method comprising: (1) subjecting the garlic syrup to aerobic fermentation and then anaerobic fermentation to obtain fermented seed liquid; (2) inoculating the fermented seed liquid into sterilized garlic syrup for anaerobic fermentation.

[0009] The present invention finds that, compared with other fermentation methods, aerobic fermentation of garlic syrup followed by anaerobic fermentation can more efficiently enrich the dominant bacterial flora adapted to garlic syrup, and the enriched characteristic bacterial flora of garlic syrup can quickly adapt to garlic syrup to proliferate and convert sugars to synthesize organic acids. The above method uses the dominant bacterial flora obtained by self-fermentation of garlic syrup to ferment organic acids, overcomes the antibacterial effect of allicin contained in garlic syrup, eliminates the step of removing allicin, simplifies the preparation process of organic acids, and significantly improves the yield of organic acids and the conversion rate of sugars contained in garlic syrup.

[0010] Garlic syrup has its particularity compared with other raw materials, and contains allicin with antibacterial activity. Therefore, before the present invention is realized, it is difficult to predict whether garlic syrup without removing allicin can be enriched by fermentation to obtain characteristic flora and used for fermentation to produce organic acid. The scheme of aerobic fermentation of garlic syrup and then anaerobic fermentation to obtain fermentation seed liquid, and then inoculating the fermentation seed liquid into sterilized garlic syrup for anaerobic fermentation to prepare organic acid-rich fermentation liquid is the key to the technical effect of the present invention, which has universality for garlic syrup raw materials and can be repeatedly implemented and reproduced.

[0011] In the present invention, the garlic syrup can be obtained by extracting garlic as a raw material through water after slicing, shredding, grinding and other raw material treatments, and concentrating it after solid-liquid separation and membrane filtration. Specifically, it can be obtained by concentrating the wastewater generated during the slicing, shredding and grinding of garlic.

[0012] Preferably, the garlic syrup is obtained by concentrating garlic slice washing water in a garlic slice production process.

[0013] Preferably, the wastewater is subjected to solid-liquid separation and / or membrane filtration treatment to remove insoluble matter before concentration.

[0014] Preferably, the total sugar content of the garlic syrup is 35%-50%.

[0015] Preferably, the allicin content of the garlic syrup is 0.005%-0.03%, more preferably 0.008%-0.03%.

[0016] Preferably, the solid content of the garlic syrup is 40%-60%.

[0017] In step (1) of the above method, the temperature of aerobic fermentation and anaerobic fermentation is 25-38°C.

[0018] Preferably, in step (1), the temperature of aerobic fermentation is 25-32°C, and the temperature of anaerobic fermentation is 33-38°C (more preferably 33-36°C).

[0019] Aerobic and anaerobic fermentation within the above temperature range is conducive to more efficient enrichment of the dominant bacterial flora adapted to garlic syrup.

[0020] Preferably, in step (1), the dissolved oxygen content of the aerobic fermentation is 10%-40%, and the stirring speed is 200-400 rpm.

[0021] Preferably, the dissolved oxygen content of aerobic fermentation is 10%-25%.

[0022] Preferably, the total sugar conversion rate at the end of aerobic fermentation is 10%-25%.

[0023] Preferably, the aerobic fermentation time is 10-25 days.

[0024] Preferably, in step (1), the anaerobic fermentation time is 20-40 days.

[0025] Preferably, the viable count of the fermented seed liquid is not less than 10 8 CFU / g. More preferably not less than 10 9 CFU / g.

[0026] The present invention optimizes the preparation process of the fermentation seed liquid, so that the number of viable bacteria in the fermentation seed liquid is high, and a higher sugar conversion efficiency can be achieved in the fermentation of step (2), thereby overcoming the inhibitory effect caused by allicin contained in the garlic syrup.

[0027] Preferably, among the live bacteria contained in the fermented seed liquid, the proportion of fungi is not less than 70%, preferably not less than 80%. The proportion of fungi refers to the percentage of fungi in terms of the number of live bacteria.

[0028] The fungi described above include one or more selected from the group consisting of Basidiomycota, Ascomycota, Chytridiomycota, Hyphomycota, Glomeromycota, Rhodopsycota, Oleobacterium, Trichomycota, Thermosporycota, Firmicutes, Proteobacteria, and Verrucomicrobia.

[0029] The present invention analyzes the microbial composition of the characteristic flora enriched in garlic syrup, and finds that fungi account for more than 70% of the characteristic flora, and the microbial composition of the characteristic flora enriched in garlic syrup prepared from garlic raw materials of different origins and sources is highly similar. The present invention verifies garlic raw materials of various origins and sources, and the results show that the method is applicable to garlic raw materials of different origins and places, and can achieve higher organic acid yield and sugar conversion rate, proving that the method can be reproduced and repeatedly implemented.

[0030] In step (2) of the above method, the temperature of anaerobic fermentation is 33-38°C.

[0031] Preferably, the fermentation time of anaerobic fermentation in step (2) is 20-40 days, more preferably 20-30 days.

[0032] Preferably, in step (2), the fermented seed liquid is inoculated at a ratio of 1:8-10. The above inoculation ratio refers to the volume ratio of the fermented seed liquid to the garlic syrup.

[0033] Preferably, in step (2), the garlic syrup is sterilized by instant high temperature and cooled to 33-38°C before being fully mixed with the fermentation seed liquid and then subjected to anaerobic fermentation.

[0034] During the anaerobic fermentation in steps (1) and (2) above, stirring is started once every 8-12 days, and each stirring is for 6-8 hours.

[0035] In step (2) of the above method, the total sugar conversion rate of the garlic syrup is not less than 60%, preferably not less than 70%.

[0036] After the anaerobic fermentation in step (2) is completed, the fermentation liquid can be obtained by sterilization.

[0037] The present invention also provides a fermentation liquid, which is prepared by the above method.

[0038] Preferably, the organic acid content in the fermentation broth is not less than 200 g / kg. More preferably, the organic acid content in the fermentation broth is not less than 220 g / kg.

[0039] The above-mentioned organic acids include lactic acid, citric acid, acetic acid, oxalic acid, fumaric acid and the like.

[0040] Preferably, the proportion of lactic acid in the organic acid is not less than 60%, more preferably not less than 70%.

[0041] The fermentation broth prepared by the above method provided by the present invention contains complex organic acids, wherein lactic acid accounts for >60%, and the organic acid content increases from 9.61 g / kg to more than 200 g / kg before and after fermentation; the total sugar content decreases from 35%-50% to 9%-15%, and the total sugar conversion rate is >60%. The fermentation broth can effectively improve the intestinal digestion level and immunity of farmed animals.

[0042] The present invention provides the use of the fermentation liquid described above or the fermentation liquid prepared by the method described above in preparing feed or feed additives, or in livestock and poultry breeding.

[0043] The present invention also provides a feed additive, which comprises the fermentation liquid prepared by the method described above.

[0044] The beneficial effects of the present invention include at least: the present invention provides a method for preparing a fermentation liquid rich in organic acid by using characteristic flora of garlic syrup fermentation, the method uses the dominant flora obtained by fermentation of garlic syrup itself to ferment organic acid, can use garlic syrup containing garlic oil or allicin as the fermentation raw material of organic acid, does not need to remove allicin from the raw material, has wider requirements for raw materials, and simplifies the preparation process of organic acid; the fermentation seed liquid enriched by the method has a high number of viable bacteria, good stability, and can achieve a high sugar conversion efficiency; the fermentation liquid prepared by the method has a high organic acid content, which can effectively improve the intestinal digestion level and immunity of farmed animals. The method provided by the present invention has the advantages of high efficiency, continuity, and low cost of industrialization, helps to ensure industrial production, and can process garlic syrup into a valuable organic acid complex to achieve resource utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0046] Figure 1The following are the analysis results of the microbial diversity of different garlic syrups in Example 1 of the present invention.

[0047] Figure 2 The results are the analysis results of the microbial diversity in the fermented seed liquid obtained by fermenting different garlic syrups in Example 1 of the present invention. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] Example 1 Garlic water (garlic slice washing water in the process of garlic slice production and processing; when changing the garlic variety to prepare garlic water, use 2% alkaline water to clean the system and replace it with tap water completely) obtained from garlic raw materials of different origins and varieties was concentrated by horizontal spiral centrifugation to remove insoluble matter such as garlic residue and soil. 10L of concentrated liquid (i.e. garlic syrup) with a solid content of 44.20%-58.90% (see Table 1 for details) was taken and placed in a sterilized fermentation tank. After aerobic fermentation for 20 days (liquid temperature 29±1℃, dissolved oxygen content 15±5%, stirring speed 300rpm), sterile air was stopped, and the liquid temperature was controlled to 34±1℃ to start anaerobic fermentation (stirring was started once every 10 days during the fermentation period, and each stirring was 7h). The number of live bacteria and microbial diversity in the fermented syrup were detected after 30 days of fermentation. The key indicators of garlic raw materials, garlic syrup and fermented seed liquid are shown in Table 1.

[0050] Table 1

[0051] Five groups of raw materials were randomly selected from the nine groups of raw materials in Table 1 to test the changes in their microbial diversity before and after fermentation. The results were as follows: Figure 1 and Figure 2The results showed that the microbial composition of the fermented seed liquid obtained by fermenting garlic syrups from garlic raw materials from different origins was highly similar. The proportion of fungi (number of live bacteria) in the live bacteria in the fermented seed liquids obtained from different syrups was more than 80%, including Ascomycota, Basidiomycota, Chytridiomycota, Mortierellomycota, Glomeromycota, Rozellomycot, Olpidiomycota, Mucoromycota, etc.

[0052] The above results show that the garlic syrup prepared from garlic of different origins and varieties has a high number of viable bacteria in the fermented seed liquid obtained after aerobic fermentation and anaerobic fermentation as described in the present invention. It can be seen that the characteristic bacterial flora of garlic syrup can be enriched using the method of the present invention.

[0053] Example 2 This embodiment provides a method for preparing a fermentation liquid rich in organic acid using garlic syrup, and the steps are as follows: (1) The garlic water (garlic slice washing water in the garlic slice production process) obtained from the garlic slice (garlic raw material from Qi County, Henan Province) production line was centrifuged with a horizontal screw centrifuge to remove insoluble matter such as garlic residue and soil, and then concentrated. 100 L of the concentrated liquid (i.e., garlic syrup) with a solid content of 40% (total sugar content of 36.90%, total allicin content of 0.0102%) was taken and placed in a sterilized fermentation tank for aerobic fermentation for 11 days (liquid temperature of 26±1°C, dissolved oxygen content of 15±5%, stirring speed of 300 rpm), and the total sugar conversion rate was 15.6%. The introduction of sterile air was stopped, and the liquid temperature was controlled to 34±1°C to start anaerobic fermentation (stirring was started once every 10 days during the fermentation period, and each stirring was for 6 hours). The number of viable bacteria in the fermented syrup was detected to be 5.3×10 on the 23rd day of fermentation. 9 CFU / g, the fungi account for 85%, and the fermentation seed liquid is obtained by stopping the fermentation.

[0054] (2) The fermented seed liquid and the sterilized garlic syrup with a solid content of 55% (total sugar content 49.50%, total allicin content 0.0119%) were mixed in a fermentation tank at a liquid temperature of 35±1°C in a ratio of 1:10, and the liquid temperature was controlled at 34±1°C for anaerobic fermentation. During the fermentation period, stirring was started once every 10 days, each time for 6 hours, and the fermentation lasted for 25 days.

[0055] After the fermentation was completed, the lactic acid content was 178.17 g / kg, citric acid 41.95 g / kg, acetic acid 12.93 g / kg, oxalic acid 5.22 g / kg, fumaric acid 0.13 g / kg and the total acid content was 238.4 g / kg, of which lactic acid accounted for 74.73%; the total sugar content before and after fermentation decreased from 45.2% to 11.97%, and the total sugar conversion rate was 73.5%.

[0056] Example 3 This embodiment provides a method for preparing a fermentation liquid rich in organic acid using garlic syrup, and the steps are as follows: (1) The garlic water (garlic slice washing water in the garlic slice production process) obtained from the garlic slice (Yongnian garlic raw material) production line was centrifuged with a horizontal screw centrifuge to remove insoluble matter such as garlic residue and soil, and then concentrated. 100L of the concentrated liquid (i.e., garlic syrup) with a solid content of 56% (total sugar content of 49.84%, total allicin content of 0.0201%) was taken and placed in a sterilized fermentation tank for aerobic fermentation for 23 days (liquid temperature of 30±1°C, dissolved oxygen content of 18±3%, stirring speed of 350rpm), and the total sugar conversion rate was 17.8%. The introduction of sterile air was stopped, and the liquid temperature was controlled to 35±1°C to start anaerobic fermentation (stirring was started once every 10 days during the fermentation period). The fermentation lasted for 40 days (stirring was started once every 10 days, and each stirring was for 7 hours). The number of viable bacteria in the fermented syrup was detected to be 3.0×10 9 CFU / g, the fungi accounted for 82%, and the fermented seed liquid was obtained.

[0057] (2) The fermented seed liquid and the sterilized garlic syrup with a solid content of 50% (total sugar 44.60%, total allicin content 0.0211%) were mixed in a fermentation tank at a liquid temperature of 34±1°C in a ratio of 1:8, and the liquid temperature was controlled at 35±1°C for anaerobic fermentation. During the fermentation period, stirring was started once every 10 days, each stirring was for 7 hours, and the fermentation lasted for 22 days.

[0058] After the fermentation was completed, the lactic acid content was 207.97 g / kg, citric acid 42.02 g / kg, acetic acid 22.73 g / kg, oxalic acid 2.05 g / kg, fumaric acid 0.09 g / kg and the total acid content was 274.86 g / kg, of which lactic acid accounted for 75.66%. The total sugar content before and after fermentation decreased from 39.60% to 8.35%, and the total sugar conversion rate was 78.90%.

[0059] Example 4 This embodiment provides a method for preparing a fermentation liquid rich in organic acid using garlic syrup, and the steps are as follows: (1) The garlic water (garlic washing water in the garlic slice production process) obtained from the garlic slice (garlic raw material from Linyi, Shandong) production line was centrifuged with a horizontal screw centrifuge to remove insoluble matter such as garlic residue and soil, and then concentrated. 100 L of the concentrated liquid (i.e., garlic syrup) with a solid content of 50% (total sugar content of 43.74%, total allicin content of 0.0182%) was taken and placed in a sterilized fermentation tank for aerobic fermentation for 25 days (liquid temperature of 28±1°C, dissolved oxygen content of 15±5%, stirring speed of 350 rpm), and the total sugar conversion rate was 15.4%. The introduction of sterile air was stopped, and the liquid temperature was controlled to 34±1°C to start anaerobic fermentation (stirring was started once every 10 days during the fermentation period). The fermentation lasted for 38 days (stirring was started once every 10 days, and each stirring was 8 hours). The number of viable bacteria in the fermented syrup was detected to be 4.1×10 9 CFU / g, the fungus accounts for 90%, and the fermented seed liquid is obtained.

[0060] (2) The fermented seed liquid and the sterilized garlic syrup with a solid content of 54% (total sugar content of 49.80%, total allicin content of 0.0188%) were mixed in a fermentation tank at a liquid temperature of 35±1°C in a ratio of 1:8, and the liquid temperature was controlled at 37±1°C for anaerobic fermentation. During the fermentation period, stirring was started once every 10 days for 8 hours each time, and the fermentation lasted for 28 days.

[0061] After the fermentation was completed, the lactic acid content was 267.81 g / kg, citric acid 81.3 g / kg, acetic acid 22.73 g / kg, oxalic acid 2.27 g / kg, fumaric acid 0.08 g / kg and the total acid content was 374.19 g / kg, of which lactic acid accounted for 71.40%. The total sugar content before and after fermentation decreased from 44.27% to 6.75%, and the total sugar conversion rate was 84.75%.

[0062] Comparative Example 1 This comparative example provides a method for preparing a fermentation liquid rich in organic acid by using garlic syrup, which is different from the method in Example 2 only in that: in step (1), anaerobic fermentation is performed first, and then aerobic fermentation is performed, and the conditions of anaerobic fermentation and aerobic fermentation are the same as those in Example 2.

[0063] The number of viable bacteria in the fermented seed liquid was detected to be 2.0×10 5 CFU / g. After the fermentation was completed and sterilized, the lactic acid content was 33.4g / kg, citric acid 0.5g / kg, acetic acid 0.2g / kg, oxalic acid 0.5 / kg, fumaric acid 0g / kg, and the total acid content was 34.6g / kg. The total sugar content before and after fermentation decreased from 45.2% to 21.23%, and the total sugar conversion rate was 53.03%.

[0064] Comparative Example 2 This comparative example provides a method for preparing a fermentation broth rich in organic acid using garlic syrup, which differs from the method in Example 3 only in that in step (1), anaerobic fermentation is performed first and then aerobic fermentation is performed, and the conditions of anaerobic fermentation and aerobic fermentation are the same as those in Example 3.

[0065] The number of viable bacteria in the fermented seed liquid was detected to be 1.8×10 6 CFU / g. After the fermentation was completed and sterilized, the lactic acid content was 15.36g / kg, citric acid 2.70g / kg, acetic acid 0.3g / kg, oxalic acid 0.02 / kg, fumaric acid 0g / kg, and the total acid content was 18.38g / kg. The total sugar content before and after fermentation decreased from 39.6% to 17.85%, and the total sugar conversion rate was 54.92%.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a fermentation liquid rich in organic acid using garlic syrup, characterized in that: The method comprises: (1) subjecting the garlic syrup to aerobic fermentation and then anaerobic fermentation to obtain fermented seed liquid; (2) inoculating the fermented seed liquid into sterilized garlic syrup for anaerobic fermentation.

2. The method according to claim 1, characterized in that The garlic syrup is obtained by concentrating the water used to wash garlic slices during the production process of garlic slices; Preferably, the total sugar content of the garlic syrup is 35%-50%; Preferably, the garlic syrup contains allicin; the content of allicin in the garlic syrup is preferably 0.005%-0.03%.

3. The method according to claim 1 or 2, characterized in that: In step (1), the temperature of aerobic fermentation and anaerobic fermentation is 25-38°C; Preferably, in step (1), the temperature of aerobic fermentation is 25-32°C, and the temperature of anaerobic fermentation is 33-38°C.

4. The method according to any one of claims 1 to 3, characterized in that In step (1), the dissolved oxygen content of aerobic fermentation is 10%-40%, and the stirring speed is 200-400 rpm; Preferably, the total sugar conversion rate at the end of aerobic fermentation is 10%-25%; More preferably, the aerobic fermentation time is 10-25 days; And / or, in step (1), the anaerobic fermentation time is 20-40 days.

5. The method according to any one of claims 1 to 4, characterized in that: The viable bacteria count of the fermented seed liquid is not less than 10 8 CFU / g; And / or, among the live bacteria contained in the fermented seed liquid, fungi account for no less than 70%.

6. The method according to claim 5, characterized in that The fungi include one or more selected from the group consisting of Basidiomycota, Ascomycota, Chytridiomycota, Hyphomycota, Glomeromycota, Rhodozygotes, Oleobacteria, Trichomycota, Thermosporycota, Firmicutes, Proteobacteria, and Verrucomicrobia.

7. The method according to any one of claims 1 to 6, characterized in that: In step (2), the temperature of anaerobic fermentation is 33-38°C; the fermentation time is preferably 20-40 days; And / or, in step (2), the fermentation seed liquid is inoculated at a ratio of 1:8-10.

8. A fermentation broth, characterized in that: It is prepared by the method described in any one of claims 1 to 7; Preferably, the organic acid content in the fermentation broth is not less than 200 g / kg; More preferably, lactic acid accounts for no less than 60% of the organic acids.

9. Use of the fermentation liquid according to claim 8 in preparing feed or feed additives, or in livestock and poultry breeding.

10. A feed additive, characterized in that: The feed additive comprises the fermentation broth prepared by the method according to any one of claims 1 to 7.

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