Method for evaluating nutritional value of fermented grain feed
By determining the chemical composition of fermented feed and in vitro simulated digestion experiments, nutritional value prediction equations were established, and the high cost and time-consuming problems of nutritional value assessment of fermented feeds in the existing technology were solved, and the rapid and accurate nutritional value was achieved. The assessment has promoted the industrial application and cost reduction of bad fermented feed.
Patent Information
- Application Number
- CN202411291891.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2024-12-17
AI Technical Summary
The prior art cannot efficiently and at low cost to assess the nutritional value of fermented feed, and depends on costly and time-consuming wet chemical methods and animal tests, and uses toxic and harmful chemical reagents.
By determining the key indicators in the chemical composition of poor fermented feed, in vitro simulated digestion experiments and regression analysis were used to establish nutritional value prediction equations, single-factor and correlation analysis were performed using SPSS software, combined with pepsin-trypsin in vitro digestion, two-step in vitro digestion In the simulated digestion experiment of rumen fluid, the lactic acid content and microbial protein content were determined, and the prediction equations of in vitro digestibility and in vitro fermentation parameters of rumen were established.
It has achieved rapid, low-cost and pollution-free nutritional value assessment, improved the accuracy of prediction, promoted the industrial application of bad fermented feed, reduced the cost of animal husbandry and improved corporate efficiency.
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Abstract
Description
Technical Field
[0001] The invention relates to a feed nutritional value assessment technology, and in particular to a method for assessing the nutritional value of lees fermented feed. Background Art
[0002] Wine lees are the solid residues left over from brewing wine from grain crops. If they are directly discarded, it will not only cause serious environmental pollution, but also lead to a waste of resources. Take white wine lees as an example. White wine lees usually contain conventional nutrients such as protein, starch, amino acids, and other nutrients, as well as vitamins, pyrimidines, and ester compounds. However, if a large amount of wine lees is directly fed to livestock, it may cause poisoning, and the protein content of untreated wine lees is not enough to be absorbed and utilized by livestock.
[0003] On the other hand, with the continuous increase in feed demand, protein feed shortage and severe supply situation are the key problems facing my country at present. Under this environment, distiller's grains fermented feed came into being. Microbial fermentation of distiller's grains can not only increase the content of protein and flavor substances, but also effectively reduce the content of toxic substances and improve in vitro digestibility. It is safer and easier for animals to absorb and utilize. It not only solves the waste of distiller's grains and reduces environmental pollution, but also alleviates the current shortage of protein feed and achieves significant social benefits.
[0004] The evaluation of the nutritional value of feed is an important task, which is conducive to understanding the nutritional value and characteristics of feed, rationally utilizing feed resources, improving feed utilization rate and providing a scientific basis for animal feeding. However, the evaluation of the nutritional value of fermented feed such as distiller's grains can only rely on wet chemical methods and animal experiments, which is a costly, time-consuming process and requires the use of a large amount of toxic and hazardous chemical reagents. Summary of the invention
[0005] The technical problem to be solved by the present invention is to propose a method for evaluating the nutritional value of fermented lees feed, so as to achieve efficient and low-cost evaluation of the nutritional value of fermented lees feed.
[0006] The technical solution adopted by the present invention to solve the above technical problems is:
[0007] A method for evaluating the nutritional value of fermented dregs feed comprises the following steps:
[0008] Determine the key indicators that affect the nutritional value of fermented feed based on its chemical composition;
[0009] The nutritional value parameters of the fermented feed were obtained by using an in vitro simulated digestion experiment.
[0010] Regression analysis was performed on the key indicators of the fermented dregs feed and the nutritional value parameters obtained from the in vitro simulated digestion experiment to establish a prediction equation for the nutritional value of the fermented dregs feed.
[0011] The nutritional value of the corresponding fermented lees feed is predicted using the prediction equation for the nutritional value of the fermented lees feed.
[0012] Furthermore, the nutritional value parameters include in vitro digestibility and rumen in vitro fermentation parameters; the rumen in vitro fermentation parameters include lactic acid content and microbial protein content.
[0013] Furthermore, the key indicators affecting the nutritional value include: fermentation days, absorbance of lactic acid and absorbance of microbial protein.
[0014] Furthermore, the established prediction equation for the nutritional value of fermented grains feed is:
[0015] In vitro digestibility: Y1=k1X1+b1;
[0016] Microbial protein content: Y2=k2X2+b2;
[0017] Lactic acid content: Y3=k3X3+b3;
[0018] Among them, Y1 is the in vitro digestibility, X1 is the fermentation days, Y2 is the microbial protein content, X2 is the absorbance of microbial protein, Y3 is the lactic acid content, X3 is the absorbance of lactic acid, k1, k2, k3 are coefficients, and b1, b2, b3 are constants.
[0019] Furthermore, regression analysis is performed on the key indicators of the fermented feed of this type and the nutritional value parameters obtained from the in vitro simulated digestion experiment, including: single factor and correlation analysis is performed on the key indicators of the fermented feed of this type and the nutritional value parameters obtained from the in vitro simulated digestion experiment through SPSS software package statistical software.
[0020] Furthermore, the lees fermented feed includes but is not limited to: liquor lees fermented feed, beer lees fermented feed, rice wine lees fermented feed, vinegar lees fermented feed or soy sauce lees fermented feed.
[0021] Furthermore, the fermented white wine grains feed is a white wine grains protein feed produced by fermentation with functional bacteria; the functional bacteria include Trichoderma viride, Lactobacillus casei, Candida utilis and Bacillus subtilis.
[0022] Furthermore, the in vitro simulated digestion experiment is a two-step in vitro digestion of pepsin and trypsin and a rumen fluid simulated digestion experiment. In the experiment, the lactic acid content is determined by HPLC, and the microbial protein content is determined by purine method.
[0023] Furthermore, the in vitro digestibility obtained by the in vitro simulated digestion experiment includes the in vitro digestibility of dry matter and the in vitro digestibility of crude protein, which are calculated as follows:
[0024] IVDMD=(DM 发酵前 -DM 发酵后 ) / DM 发酵前 ×100%
[0025] IVCPD=(CP 发酵前 ×DM 发酵前 -CP 发酵后 ×DM 发酵后 ) / CP 发酵前 ×DM 发酵前 ×100%
[0026] IVDMD is the in vitro digestibility of dry matter, DM 发酵前 is the dry matter content before fermentation, DM 发酵后 is the dry matter content after fermentation, IVCPD is the in vitro digestibility of crude protein, CP 发酵前 is the crude protein content before fermentation, CP 发酵后 It is the crude protein content after fermentation.
[0027] The beneficial effects of the present invention are:
[0028] The present invention determines key indicators that affect nutritional value parameters through chemical composition analysis during the fermentation feed process, and performs regression analysis in combination with nutritional value parameters obtained from a two-step in vitro digestion with pepsin and trypsin and a simulated digestion experiment with rumen fluid, thereby establishing a prediction equation for the corresponding nutritional value. That is, the nutritional value of the finished feed after fermentation and the in vitro digestion simulation conditions can be quickly predicted based on the indicator parameters during the feed fermentation period, thereby determining whether the fermented feed is conducive to digestion and absorption by ruminants, and providing a theoretical basis for animal production practice and feeding.
[0029] The scheme combining the in vitro digestion simulation method with the chemical composition determination provided by the present invention will improve the accuracy of prediction, thereby being able to more reliably estimate the nutritional value of feed ingredients; the rapid, low-cost, and pollution-free nutritional value assessment method will help promote the industrial application of lees-type feed, realize rapid detection of lees-type fermented feed, reduce costs, and increase corporate benefits. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1 The present invention is a flow chart of the method for evaluating the nutritional value of fermented grains feed. DETAILED DESCRIPTION
[0031] During the fermentation process of dregs feed, some key index parameters will affect the nutritional value of the finished feed after fermentation. Therefore, these key indexes that affect the nutritional value parameters are determined by analyzing the chemical composition of the fermentation process of dregs feed; and the pepsin-trypsin two-step in vitro digestion and rumen fluid simulated digestion experiment have the characteristics of accuracy, small sample volume and non-destructiveness, and can be used to determine the nutritional value of the finished feed and simulate in vitro digestion. Accordingly, the present invention conducts correlation regression analysis on the key indexes of dregs fermented feed determined by component analysis and the nutritional value parameters obtained by in vitro simulated digestion experiment, so as to establish a prediction equation for the nutritional value of dregs fermented feed; using this prediction equation, the nutritional value of the finished feed after fermentation and the in vitro digestion simulation can be quickly predicted according to the index parameters during the feed fermentation period. The implementation of this scheme is of great significance for promoting the feed utilization of dregs and other resources, reducing the cost of animal husbandry, and improving the competitiveness of animal husbandry.
[0032] The method for evaluating the nutritional value of fermented dregs feed provided by the present invention is as follows Figure 1 , which comprises the following steps:
[0033] S1. Determine the key indicators that affect the nutritional value of fermented feed according to its chemical composition;
[0034] S2. Obtaining the nutritional value parameters of the fermented feed by using an in vitro simulated digestion experiment;
[0035] S3, performing regression analysis on the key indicators of the fermented dregs feed and the nutritional value parameters obtained from the in vitro simulated digestion experiment, and establishing a prediction equation for the nutritional value of the fermented dregs feed;
[0036] S4. Utilizing the above-mentioned prediction equation for the nutritional value of fermented lees feed, the nutritional value of the corresponding fermented lees feed is predicted.
[0037] Example
[0038] This embodiment takes the nutritional value assessment of fermented feed of white wine lees as an example, and its implementation process is as follows:
[0039] (1) Liquor lees fermentation:
[0040] Wet vinasse was first dried and then crushed, and the functional flora cultivated was controlled to be 12% in inoculation amount, and the fermentation system (30L fermentation system) of 30L fermentation tank 3000g vinasse was loaded, and 3000mL distilled water was added to control the water content to be 50% mixed, and 2% of urea was added as an external nitrogen source, and agitator was used to stir for 2 hours at 30rpm to ensure that the material was fully mixed. Control ventilation 3L / min, agitator speed was set to 3.5rpm, and fermented for 9 days at 34°C. Ventilation was stopped on the 10th day, and Lactobacillus casei was accessed, and the rotating speed was 10rpm, and fermentation continued for 3 days.
[0041] (2) Nutritional value parameter measurement:
[0042] The distiller's grains protein feed produced by fermentation in the above method (1) is dried and crushed, and its lactic acid content and microbial protein content are determined by passing through a 40-mesh sieve (0.425 mm). The measurement of lactic acid content can be achieved using the hydroxybiphenyl method. The microbial protein content can be achieved using the purine method, using the absorbance value of yeast RNA at 260 nm as a standard curve. The relationship between the optical density value and the yeast RNA content, the RNA measured value can be determined by measuring the optical density value, and the microbial protein MCP content is calculated according to the following formula:
[0043]
[0044] Among them, the nitrogen content of RNA is 17.83%, and the nitrogen content of RNA in bacterial nitrogen is 10%.
[0045] (3) Determination of in vitro digestibility:
[0046] The rumen fluid was collected and stored in an anaerobic environment. After the rumen fluid was stirred and mixed, the feed residue was filtered out with 4 layers of gauze. The filtered rumen fluid was collected in a preheated 5L beaker and CO2 gas was continuously introduced. Then, the filtered rumen fluid was quickly mixed with the buffer solution at a ratio of 1:2 to prepare the artificial rumen culture fluid.
[0047] The distiller's grains protein feed produced by fermentation in the method described in (1) was dried and crushed, and passed through a 40-mesh sieve (0.425 mm) as the experimental substrate. This experiment was divided into 4 groups, including 1 blank control group and 3 experimental groups. The blank control group only had rumen fluid without substrate to deduct the effect of rumen fluid fermentation itself. The 3 experimental groups included: Group T1: raw distiller's grains; Group T2: distiller's grains protein feed of 250 mL fermentation system; Group T3: distiller's grains protein feed of 30 L fermentation system.
[0048] Each experimental group was crushed through a 40-mesh sieve (0.425 mm), and 1.50 g of substrate particles were taken and placed in a brown bottle one day before the experiment. On the second day, 200 mL of artificial rumen culture medium was added to each bottle and mixed well, and then quickly placed in a constant temperature shaker preheated at 39°C for cultivation, and the shaking frequency was adjusted to 150 rpm. The gas production was measured at 4h, 14h, 24h, and 48h of fermentation, and the fermentation was terminated at 48h by taking out and placing in an ice water bath.
[0049] After washing the gauze with distilled water, put it in a 105°C oven and dry it to constant weight and record the value. Filter the rumen fermentation liquid with 4 layers of gauze that have been constant weight. Wash the filtered solids three times with distilled water and put them in a 105°C oven and dry them to constant weight. Record the data for calculating the in vitro digestibility of dry matter (IVDMD). The in vitro digestibility of crude protein (IVCPD) is determined using a Kjeldahl nitrogen analyzer. The calculation method is as follows:
[0050] IVDMD=(DM 发酵前 -DM 发酵后 ) / DM 发酵前 ×100%
[0051] IVCPD=(CP 发酵前 ×DM 发酵前 -CP 发酵后 ×DM 发酵后 ) / CP 发酵前 ×DM 发酵前 ×100%
[0052] IVDMD is the in vitro digestibility of dry matter, DM 发酵前 is the dry matter content before fermentation, DM 发酵后 is the dry matter content after fermentation, IVCPD is the in vitro digestibility of crude protein, CP 发酵前 is the crude protein content before fermentation, CP 发酵后 It is the crude protein content after fermentation.
[0053] After the above three experimental groups were tested separately, the digestion results of each experimental group were obtained and are shown in Table 1 below.
[0054] Table 1: Digestion results of each experimental group
[0055] Digestibility T1 Group T2 Group T3 Group IVDMD 17.66％ 35.03％ 28.61％ IVCPD 42.55％ 52.93％ 48.69％
[0056] (4) Statistics and correlation analysis:
[0057] The nutritional value parameters obtained were comprehensively analyzed by univariate and correlation analysis using SPSS statistical software, and equations were established. Some examples of the constructed regression equations are shown in Table 2 below.
[0058] Table 2: Equations related to predictor variables
[0059] Predictor variables Regression equation <![CDATA[R 2 ]]> IVCPD <![CDATA[Y1=0.01X1+0.009]]> 0.99991 MCP <![CDATA[Y2=0.73X2-0.45]]> 0.99659 LA <![CDATA[Y3=4.76X3+0.02]]> 0.99836
[0060] Among them, IVCPD is the in vitro digestibility of crude protein, MCP is the microbial protein content, and LA is the lactic acid content.
[0061] Verification example:
[0062] By fermenting a batch of distiller's grains that a breeding enterprise intends to purchase and verifying the regression equation obtained in the experimental example, two groups of experiments were conducted to select a better way to ferment distiller's grains feed. Group T1: distiller's grain protein feed with a 250mL fermentation system; Group T2: distiller's grain protein feed with a 30L fermentation system. All samples were tested for microbial protein in the laboratory using traditional methods. At the same time, a small amount of samples was taken to determine the in vitro digestibility, and these indicators were quickly predicted. The specific operation method is the same as the above experimental example. The test results are shown in Table 3 below.
[0063] Table 3: Test items and contents
[0064] Detection items T1 content T2 content Microbial Protein 1.66mg / mL 1.61mg / mL In vitro digestibility 35.03％ 28.61％
[0065] According to the above test results, the microbial protein content of the distillers grains feed produced by the T2 group was slightly lower than that of the T1 group, and the in vitro digestibility of the T1 group was significantly higher than that of the T2 group. This shows that the fermentation method of the T1 group is better than that of the T2 group, and can obtain higher protein yield and is easier to digest.
[0066] Finally, it should be noted that the above embodiments are only preferred implementations and are not intended to limit the present invention. It should be pointed out that for those skilled in the art, several modifications, equivalent replacements, improvements, etc. can be made without departing from the scope of the present invention and the scope of protection of the claims, and all of these should be included in the protection scope of the present invention.
Claims
1. A method for evaluating the nutritional value of fermented grains feed, characterized in that: The following steps are involved: Determine the key indicators that affect the nutritional value of fermented feed based on its chemical composition; The nutritional value parameters of the fermented feed were obtained by using an in vitro simulated digestion experiment. Regression analysis was performed on the key indicators of the fermented dregs feed and the nutritional value parameters obtained from the in vitro simulated digestion experiment to establish a prediction equation for the nutritional value of the fermented dregs feed. The nutritional value of the corresponding fermented lees feed is predicted using the prediction equation for the nutritional value of the fermented lees feed.
2. The method for evaluating the nutritional value of fermented grains feed according to claim 1, characterized in that: The nutritional value parameters include in vitro digestibility and rumen in vitro fermentation parameters; the rumen in vitro fermentation parameters include lactic acid content and microbial protein content.
3. A method for evaluating the nutritional value of fermented grains feed according to claim 2, characterized in that: The key indicators affecting the nutritional value include: fermentation days, absorbance of lactic acid and absorbance of microbial protein.
4. A method for evaluating the nutritional value of fermented grains feed as claimed in claim 3, characterized in that: The regression analysis of the key indicators of the fermented feed of this type and the nutritional value parameters obtained by the in vitro simulated digestion experiment includes: using SPSS software package statistical software to perform univariate and correlation analysis on the key indicators of the fermented feed of this type and the nutritional value parameters obtained by the in vitro simulated digestion experiment.
5. A method for evaluating the nutritional value of fermented grains feed according to claim 4, characterized in that: The established prediction equation for the nutritional value of fermented dregs feed is: In vitro digestibility: Y1=k1X1+b1; Microbial protein content: Y2=k2X2+b2; Lactic acid content: Y3=k3X3+b3; Among them, Y1 is the in vitro digestibility, X1 is the fermentation days, Y2 is the microbial protein content, X2 is the absorbance of microbial protein, Y3 is the lactic acid content, X3 is the absorbance of lactic acid, k1, k2, k3 are coefficients, and b1, b2, b3 are constants.
6. A method for evaluating the nutritional value of fermented grains feed according to any one of claims 1 to 5, characterized in that: The lees fermented feed includes: feed fermented by liquor lees, feed fermented by beer lees, feed fermented by rice wine lees, feed fermented by vinegar lees or feed fermented by soy sauce lees.
7. A method for evaluating the nutritional value of fermented grains feed according to claim 6, characterized in that: The fermented white wine lees feed is a white wine lees protein feed produced by fermentation with functional bacteria; the functional bacteria include trichoderma viride, lactobacillus casei, candida utilis and bacillus subtilis.
8. A method for evaluating the nutritional value of fermented grains feed according to any one of claims 1 to 5, characterized in that: The in vitro simulated digestion experiment is a pepsin-trypsin two-step in vitro digestion and a rumen fluid simulated digestion experiment. In the experiment, the lactic acid content is determined by HPLC, and the microbial protein content is determined by purine method.
9. A method for evaluating the nutritional value of fermented grains feed according to claim 8, characterized in that: The in vitro digestibility obtained by the in vitro simulated digestion experiment includes the in vitro digestibility of dry matter and the in vitro digestibility of crude protein, which are calculated as follows: IVDMD=(DM 发酵前 -DM 发酵后 ) / DM 发酵前 ×100% IVCPD=(CP 发酵前 ×DM 发酵前 -CP 发酵后 ×DM 发酵后 ) / CP 发酵前 ×DM 发酵前 ×100% IVDMD is the in vitro digestibility of dry matter, DM 发酵前 is the dry matter content before fermentation, DM 发酵后 is the dry matter content after fermentation, IVCPD is the in vitro digestibility of crude protein, CP 发酵前 is the crude protein content before fermentation, CP 发酵后 It is the crude protein content after fermentation.