Nutrition regulation method for improving beef quality and fatty acid composition

Abstract

The invention is suitable for the technical field of food processing, and provides a nutrition regulation and control method for improving beef quality and fatty acid composition, which comprises the following steps: in the later fattening period of beef cattle, regulating and controlling the content of vitamin A in a concentrate daily ration, or adding vegetable oil, and feeding the beef cattle; wherein the content of protein in the concentrate daily ration is 11-15%, the energy level is 2.6-3.0 Mcal / kg DM, and the content of vitamin A in the fattening period is lower than 1700 IU / kg DM; the content of vitamin A is regulated and controlled to be 5000 IU / kg DM in the later stage of fattening; the addition amount of the vegetable oil is 3% of dry matter of the daily ration of the concentrate. Vitamin A and vegetable oil are regulated and controlled in the later stage of fattening, intramuscular fat deposition and marbling score are remarkably improved, beef fatty acid composition is optimized, and collaborative improvement of beef quality grade and nutritional value is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to a nutritional regulation method for improving beef quality and fatty acid composition. Background Art

[0002] With the rapid development of my country's economy and the significant improvement in people's living standards, consumer demand for high-quality beef is growing. In particular, demand for marbled beef, characterized by exceptional tenderness, juiciness, and flavor, continues to rise. In the production of marbled beef, intramuscular fat deposition is a key factor in determining beef quality, directly impacting its market value and consumer acceptance. Typically, producing high-end or premium marbled beef requires long-term fattening of cattle, a process that inevitably leads to increased production costs. This situation is primarily due to a lack of scientifically effective nutritional regulation technologies and animal husbandry management methods.

[0003] Currently, the nutritional regulation methods commonly used in the beef cattle industry mainly include adjusting feed formulas and regulating vitamin A content. Among them, vitamin A restriction technology for fattening beef cattle has been widely adopted in the industry, but during implementation, it is still difficult to achieve the desired marbled beef grade due to unclear technical points. For example, as described in the published patent (CN1785034A), the content of vitamin A and carotene in beef fattening feed is lower than the recommended amount (2200 IU / kg DM) of beef cattle nutrition standards. After feeding for more than 90 days, the increase in intramuscular fat deposition is only from less than 1% to about 1.5%. Although the increase is larger than that of the control group, it still belongs to the A1-A2 grade level and has not yet reached the category of high-end marbled beef. Moreover, there are still many unclear technical points about how to deal with beef cattle after the fattening period.

[0004] Furthermore, vegetable oils, as natural feed additives, have attracted attention for their rich content of unsaturated fatty acids and their antioxidant and other bioactive properties. Soybean oil, the second-largest vegetable oil produced globally, is rich in n-6 polyunsaturated fatty acids, including linoleic acid. Rapeseed oil, rich in oleic acid and α-linolenic acid, shows promise in improving the fatty acid profile of animal products. Some studies have shown that adding vegetable oils to pig and sheep feed can improve the fatty acid profile of meat. In beef cattle, researchers have also experimented with using fatty acid supplements to promote weight gain and fat deposition. Existing technology discloses that rapeseed oil can enhance the tenderness of beef and improve its flavor. However, published dissertation research shows that adding rapeseed oil to fattening cattle increases subcutaneous fat deposition, while the increase in intramuscular fat deposition is limited to 19.59 mg / g. Although there is a difference compared with the control group, it still falls into the category of A1 beef and does not achieve a substantial improvement in the grade of beef. As for the fatty acid composition, the study only mentions that the addition of edible oil during the fattening process of beef cattle can increase its oleic acid content, but does not produce substantial changes to functional substances such as EPA and DHA.

[0005] Although the application of vegetable oils in animal husbandry has a certain foundation, there are still many technical difficulties in the field of regulating intramuscular fat deposition in beef cattle. First, the existing nutritional regulation technology can often only improve one aspect of the quality index of beef. It is difficult to achieve the dual goals of improving the marbling grade and optimizing the nutritional composition of fatty acids at the same time. This technical challenge is one of the difficulties in the field of animal husbandry nutrition, because increasing the intramuscular fat content while improving the nutritional value of fatty acids requires finding a balance in the complex metabolic regulation network; secondly, the specific effects of different vegetable oils on intramuscular fat deposition in beef cattle vary significantly, but their mechanism of action is still unclear, and there is a lack of theoretical basis to provide precise guidance for production practice.

[0006] In addition, existing technologies have limited effects in improving the fatty acid composition of beef, especially in reducing the n-6 / n-3 fatty acid ratio and increasing the content of beneficial fatty acids such as EPA and DHA. There are technical bottlenecks, which make it difficult to meet consumers' growing demand for nutritious and healthy beef products; at the same time, there is a lack of systematic nutritional regulation technology solutions for local cattle breeds and related hybrid cattle, which has affected the large-scale production and industrial development of high-quality beef; especially in the critical stage of fattening beef cattle in the late stage, how to improve the fatty acid nutritional composition while improving the marbling score through simple, effective and economically feasible nutritional intervention methods to achieve a synergistic improvement in beef grade and nutritional quality is a core issue that urgently needs to be broken through in current beef cattle nutritional regulation technology. This is not only related to the economic benefits of the beef cattle industry, but also to the development of the high-quality beef industry and the nutritional and health needs of consumers. Summary of the Invention

[0007] The purpose of the embodiments of the present invention is to provide a nutritional regulation method for improving beef quality and fatty acid composition, aiming to solve the problems raised in the above background technology.

[0008] The embodiment of the present invention is achieved by a nutritional regulation method for improving beef quality and fatty acid composition, comprising the following steps: in the late fattening period of beef cattle, regulating the content of vitamin A in concentrate rations, or adding vegetable oil, and feeding the beef cattle;

[0009] wherein the concentrate diet contains 11-15% protein, 2.6-3.0Mcal / kg DM of energy, and contains less than 1700IU / kg DM of vitamin A during the fattening period;

[0010] In the late fattening period, the vitamin A content is regulated to 5000 IU / kg DM;

[0011] The amount of vegetable oil added is 3% of the dry matter of the concentrate diet.

[0012] Preferably, the vegetable oil is rapeseed oil or soybean oil.

[0013] Preferably, the late fattening period is from 24 to 30 months of age.

[0014] Preferably, the step of regulating the content of vitamin A in the concentrate diet comprises increasing the content of vitamin A in the concentrate diet to 5000 IU / kg DM between 24 and 30 months of age.

[0015] Preferably, the step of adding vegetable oil comprises: adding 3% vegetable oil of the dry matter of the concentrate diet to the concentrate diet during the period from 26±1 months to 30 months of age.

[0016] Preferably, the feeding is twice daily.

[0017] The embodiments of the present invention provide a nutritional regulation method for improving beef quality and fatty acid composition, which regulates vitamin A and vegetable oil in the late fattening stage, significantly improves intramuscular fat deposition and marbling scores, and optimizes the fatty acid composition of beef, especially reducing the n-6 / n-3 fatty acid ratio and increasing the content of beneficial fatty acids such as EPA, DHA and conjugated linoleic acid, thereby achieving a synergistic improvement in beef quality grade and nutritional value, and providing technical support for the large-scale production of high-quality beef in the beef cattle industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1The effect of adding vitamin A in the late fattening period on the marbling grade of beef cattle provided by the embodiment of the present invention (A, experimental fattening strategy; B, schematic diagram of the marbling levels of different grades A1-A5 beef; C, the effect of vitamin A on the marbling grade of beef cattle);

[0019] Figure 2 The effect of adding soybean oil or rapeseed oil in the late fattening period on the marbling grade of beef cattle provided by the embodiment of the present invention (CON: control group; SO: soybean oil addition group; RO: rapeseed oil addition group);

[0020] Figure 3 Effects of adding soybean oil and rapeseed oil in the late fattening period on the CLA, DHA, EPA, and ω-6 fatty acid / ω-3 fatty acid composition of beef provided by the embodiments of the present invention (capital letters in the bar graph indicate extremely significant differences, P < 0.01);

[0021] Figure 4 Effects of adding soybean oil and rapeseed oil in the late fattening period on proteins related to intramuscular fat deposition in beef cattle provided by the embodiments of the present invention (lowercase letters in the bar graph indicate significant differences, P<0.05);

[0022] Figure 5 Effects of adding soybean oil and rapeseed oil in the late fattening period on signaling pathways related to intramuscular fat deposition in beef cattle provided by the embodiments of the present invention (lowercase letters in the bar graph indicate significant differences, P<0.05). DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] A nutritional regulation method for improving beef quality and fatty acid composition comprises the following steps:

[0025] Healthy beef cattle in the late fattening stage were selected as research subjects, with Wagyu hybrid cattle or Yanbian yellow cattle or beef cattle breeds of the same quality being preferred. During the fattening period of beef cattle, vitamin A restricted feeding management (the vitamin A content in the diet was less than 1700 IU / kgDM) was implemented at the same time. The concentrate diet used a soybean meal-free diet with corn, wheat, barley, and miscellaneous meal as the main raw materials, specifically including corn, flaked corn, wheat, flaked wheat, wheat bran, second meal, barley, flaked barley, sorghum, brewer's grains, corn germ meal, molasses, DDGS, rice bran, rice bran, rice bran meal, alfalfa pellets, palm kernel meal, cottonseed meal, sunflower meal and other raw materials. Due to the large differences in the nutritional levels of different batches of raw materials, the formula needs to be readjusted every 2 weeks, and a fixed formula cannot be used to ensure that the protein content of the nutrient composition of the beef cattle diet is between 11-15% and the energy level is between 2.6-3.0 Mcal / kgDM;

[0026] From 24 months of age in the late fattening stage until slaughter (this time point is usually 30 months of age, which can be adjusted according to different pasture conditions), add vitamin A to the concentrate diet and adjust the vitamin A content in the diet to 5000 IU / kg DM. Mix the vitamin A and concentrate diet thoroughly and feed twice daily. Control the feeding amount according to the beef cattle feeding standards to ensure that the cattle consume all the food.

[0027] Alternatively, in addition to vitamin A supplementation, add food-grade / feed-grade rapeseed oil or soybean oil to the concentrate diet (strictly control the amount added to 3% of the dry matter of the diet) starting at 26 ± 1 months of age in the late fattening period until slaughter (this time point is usually 30 months of age, but can be adjusted depending on the pasture conditions). Thoroughly mix the rapeseed oil or soybean oil with the concentrate diet and feed it twice daily. Control the feeding amount according to the beef cattle feeding standards to ensure that the cattle consume all the food.

[0028] Key indicators need to be monitored and tested regularly during the breeding process.

[0029] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0030] Example 1: Analysis of the effect of vitamin A on beef quality and fatty acid composition:

[0031] Healthy Wagyu hybrid cattle aged 24 months in the late fattening stage were selected as the research subjects and the cattle were randomly divided into a control group and an experimental group (vitamin A treated group) for comparative experiments.

[0032] To improve marbling scores, vitamin A restriction was implemented during the fattening period (the vitamin A content in the diet was less than 1700 IU / kg DM). The experimental group was fed a concentrate diet consisting of corn, flaked corn, wheat, flaked wheat, wheat bran, off-meal, barley, flaked barley, sorghum, brewer's grains, corn germ meal, molasses, DDGS, rice bran, rice bran, rice bran meal, alfalfa pellets, palm kernel meal, cottonseed meal, and sunflower meal. Due to significant variability in the nutritional levels of different batches of raw materials, the formula needed to be readjusted every two weeks, and a fixed formula could not be used. Ultimately, the protein content of the beef cattle diet was maintained at 12% and the energy level was maintained at 2.9 Mcal / kg DM. The control group was fed a coarse diet consisting primarily of straw.

[0033] In the experimental group, vitamin A was added to the concentrate diet to adjust the vitamin A content of the entire diet to 5000 IU / kg DM. The cattle were fed twice daily during the experimental period. The feeding amount was controlled according to the beef cattle feeding standards to ensure that the cattle were fully fed. The entire experimental group's feeding cycle was the late fattening period of the beef cattle, from 24 months of age to 30 months of age, and then slaughtered.

[0034] After slaughter, the carcass is assessed for marbling grade according to the corresponding beef grading standards, and key production performance indicators such as carcass weight, eye muscle area, and backfat thickness are measured;

[0035] The results are shown in Table 1:

[0036] Table 1 Effects of vitamin A supplementation in the late fattening period on marbling scores and carcass traits of beef cattle

[0037]

[0038] Among them, the marble pattern scoring level is: 500 = A5, 400 = A4, 300 = A3, 200 = A2, 100 = A1;

[0039] Effect of adding vitamin A in the late fattening period on improving the marbling grade of beef cattle Figure 1 As shown;

[0040] According to Table 1 and Figure 1 It can be seen that vitamin A (VA) supplementation in the late fattening period of beef cattle improved various slaughter indicators (see Table 1). The marbling score increased from 241.4 to 305.6, with a highly significant improvement (P < 0.01), and backfat thickness also decreased significantly (P < 0.05). Figure 1 The results show that adding vitamin A in the late fattening stage can significantly increase the yield of A3 and above beef (P=0.01), and there is also a certain breakthrough in the extremely high-quality A5 grade.

[0041] Example 2: Analysis of the effects of vegetable oils on beef quality and fatty acid composition:

[0042] Healthy Wagyu hybrid cattle aged 26±1 months in the late fattening stage were selected as research subjects. The cattle were randomly divided into a control group and an experimental group (rapeseed oil group and soybean oil group) for comparative experiments.

[0043] To improve marbling scores, vitamin A restriction was implemented during the fattening period (the vitamin A content in the diet was less than 1700 IU / kg DM). The experimental group was fed a concentrate diet consisting of corn, flaked corn, wheat, flaked wheat, wheat bran, off-meal, barley, flaked barley, sorghum, brewer's grains, corn germ meal, molasses, DDGS, rice bran, rice bran, rice bran meal, alfalfa pellets, palm kernel meal, cottonseed meal, and sunflower meal. Due to significant variability in the nutritional levels of different batches of raw materials, the formula needed to be readjusted every two weeks, and a fixed formula could not be used. Ultimately, the protein content of the beef cattle diet was maintained at 12% and the energy level was maintained at 2.9 Mcal / kg DM. The control group was fed a coarse diet consisting primarily of straw.

[0044] All cattle were fed a diet with vitamin A content adjusted to 5000 IU / kgDM starting at 24 months of age in the late fattening period.

[0045] In the experimental group, edible / feed-grade rapeseed oil or soybean oil was added to the concentrate diet (the addition amount was strictly controlled to 3% of the dry matter of the diet). The rapeseed oil or soybean oil was thoroughly mixed with the concentrate diet and fed twice daily. The feeding amount was controlled according to the beef cattle feeding standards to ensure that the cattle were fully fed. The entire experimental group's feeding cycle was the late fattening period of the beef cattle, feeding from 26±1 months of age to 30 months of age, and then slaughtered.

[0046] After slaughter, the carcass is assessed for marbling grade according to the corresponding beef grading standards, and key production performance indicators such as carcass weight, eye muscle area, and backfat thickness are measured;

[0047] The results are shown in Table 2:

[0048] Table 2 Effects of adding soybean oil and rapeseed oil in the late fattening period on marbling scores and carcass traits of beef cattle

[0049]

[0050] Among them, the marble pattern scoring level is: 500 = A5, 400 = A4, 300 = A3, 200 = A2, 100 = A1;

[0051] Effect of adding soybean oil or rapeseed oil on improving the marbling grade of beef cattle in the late fattening period Figure 2As shown;

[0052] According to Table 2 and Figure 2 It can be seen that by adding 3% rapeseed oil in the late fattening period of beef cattle, the marbling score can be significantly increased from 185.71 points in the control group to 366.67 points, an increase of 97.4% (see Table 2), significantly improving the marbling grade and economic value of beef. At the same time, the carcass weight is significantly increased, bringing significant economic benefits to farmers. Figure 2 It can be seen that adding 3% soybean oil or rapeseed oil in the late fattening period increased the yield of A3 and above beef. In the rapeseed oil-added group, the proportion of A3 appeared 100%, and the yield of A4 and above grades and A5 grades reached 50% and 17% respectively.

[0053] At the same time, samples of the longissimus dorsi muscle between the 12th and 13th ribs were collected for nutritional quality analysis, focusing on the changes in fatty acid composition, especially the determination of conjugated linoleic acid (CLA) content. The fatty acids in the muscle samples were methylated and analyzed by gas chromatography to accurately determine the content of CLA isomers including cis-9 trans-11 conjugated linoleic acid and trans-10 cis-12 conjugated linoleic acid, as well as the content of n-3 polyunsaturated fatty acids such as EPA and DHA. The changes in the n-6 / n-3 fatty acid ratio were calculated, and the results were as follows: Figure 3 As shown in the figure, it can be seen that the fatty acid composition of beef can be significantly improved by adding 3% vegetable oil in the late fattening period of beef cattle. The addition of 3% rapeseed oil can reduce the n-6 / n-3 fatty acid ratio from 55.62 in the control group to 33.41, a decrease of 39.9%. At the same time, it can significantly increase the content of n-3 polyunsaturated fatty acids such as EPA and DHA, and increase the content of functional fatty acids such as cis-9 trans-11 conjugated linoleic acid and trans-10 cis-12 conjugated linoleic acid (see Figure 3 ), which greatly improved the nutritional value and health functions of beef;

[0054] To gain a deeper understanding of the molecular mechanism by which vegetable oils regulate intramuscular fat deposition, key signaling pathway proteins in muscle tissue were detected and analyzed. Western blot was used to detect the expression levels and phosphorylation status of proteins related to the PI3K / AKT / mTOR signaling pathway axis in muscle samples, including quantitative analysis of phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), target of rapamycin (mTOR) and their phosphorylated forms. At the same time, the expression changes of key regulatory proteins such as peroxisome proliferator-activated receptor γ (PPARγ), sterol regulatory element binding protein 1 (SREBP1), and fatty acid binding protein 4 (FABP4) related to adipogenesis were detected, as well as the expression levels of key enzymes of fat synthesis such as fatty acid synthase (FASN), acetyl-CoA carboxylase (ACACA), and stearoyl-CoA desaturase (SCD). The results are as follows: Figures 4 and 5 As shown in the results, it is shown that vegetable oils can upregulate the expression of key lipogenic transcription factors such as PPARγ and SREBP1, and promote the activity of lipogenic enzymes such as FASN, ACACA, and SCD (see Figure 4 ), specifically activates the PI3K / AKT / mTOR signaling axis and inhibits the Wnt / β-catenin signaling axis (see Figure 5 ), promotes intramuscular fat deposition and improves fatty acid composition, provides clear theoretical guidance for nutritional regulation of beef cattle, and fills the technical gap in this field.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A nutritional regulation method for improving beef quality and fatty acid composition, characterized in that: The following steps are involved: In the late fattening stage of beef cattle, the content of vitamin A in concentrate diet is regulated, or vegetable oil is added to feed beef cattle; wherein the concentrate diet contains 11-15% protein, 2.6-3.0Mcal / kg DM of energy, and contains less than 1700IU / kg DM of vitamin A during the fattening period; In the late fattening period, the vitamin A content is regulated to 5000 IU / kg DM; The amount of vegetable oil added is 3% of the dry matter of the concentrate diet.

2. The nutritional regulation method for improving beef quality and fatty acid composition according to claim 1, characterized in that: The vegetable oil is rapeseed oil or soybean oil.

3. The nutritional regulation method for improving beef quality and fatty acid composition according to claim 1, characterized in that: The late fattening period is from 24 to 30 months of age.

4. The nutritional regulation method for improving beef quality and fatty acid composition according to claim 3, characterized in that: The step of regulating the content of vitamin A in the concentrate diet is specifically as follows: during the period from 24 months to 30 months of age, the content of vitamin A in the concentrate diet is increased to 5000 IU / kg DM.

5. The nutritional regulation method for improving beef quality and fatty acid composition according to claim 3, characterized in that: The step of adding vegetable oil specifically comprises: adding 3% vegetable oil of the dry matter of the concentrate diet to the concentrate diet during the period from 26±1 months to 30 months of age.

6. The nutritional regulation method for improving beef quality and fatty acid composition according to claim 1, characterized in that: The feeding was twice a day.

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