Emulsified phytosterol for improving quality of white rabbits as well as preparation method and application of emulsified phytosterol

Abstract

The invention discloses emulsified phytosterol capable of improving the quality of white rabbits and a preparation method and application of the emulsified phytosterol, and belongs to the technical field of rabbit feed additives.The preparation method comprises the following steps that S1, raw materials are prepared; s2, heating and oil phase pretreatment; s3, preparing a water phase; s4, mixing oil and water; s5, performing emulsification treatment; s6, cooling and stabilizing; and S7, detecting the product. According to the preparation method, phytosterol is taken as a raw material, 2.0-3.0% of sucrose ester is taken as an emulsifier, emulsification is performed for 30-50 min at the emulsification temperature of 30-50 DEG C, and emulsification treatment is performed to prepare emulsified phytosterol, so that the preparation process conditions of the emulsified phytosterol are optimized, the most suitable additive amount of the emulsified phytosterol as a feed additive in feeding of white rabbits is determined, and a theoretical reference can be provided for industrial production of feed.

Description

Technical Field

[0001] The invention relates to the technical field of rabbit feed additives, in particular to an emulsified phytosterol for improving the quality of white rabbits and a preparation method and application thereof. Background Art

[0002] In 2008, my country's Ministry of Agriculture and Rural Affairs approved the use of plant sterols as a new functional feed additive in commercial livestock and poultry feed. Plant sterols have diverse functions, including lowering cholesterol, regulating hormone levels, promoting metabolism, preventing cardiovascular diseases, and anti-tumor effects. However, plant sterols are poorly water-soluble and have a very low absorption rate in animals, which affects their biological functions and application effects in animal production. The use of emulsifiers to emulsify plant sterols can effectively reduce the surface tension of the two phases, improve the absorption capacity of plant sterols in animals, and promote body fat metabolism as well as the body's immune and antioxidant abilities. This has become a research hotspot for the application of plant sterol feed additives in recent years.

[0003] Rabbit meat is a healthy meat with three highs and three lows, and is favored by people. The consumer market is gradually expanding and has great market potential[1]. Fujian White Rabbit is a local meat rabbit breed in China. It was listed in the "List of Livestock and Poultry Genetic Resources Protection in Fujian Province" and the "Chinese Livestock and Poultry Genetic Resources" in 2015[2]. Fujian White Rabbit is a small rabbit with various breeds and different fur colors. In recent years, the demand for Fujian White Rabbit has increased in some places, and the market sales are good. The number of breeding has increased year by year[3]. However, its main disadvantage is slow growth rate and low meat production performance, so feeding Fujian White Rabbit is particularly important[4]. Appropriate feed additives can improve the quality of rabbit meat, but because the country prohibits feed additives such as clenbuterol and has strict inspections on drug residues. Therefore, in order to improve the quality of rabbit meat, obtain greater nutritional value, and achieve higher economic benefits, it is of great significance to explore greener feed additives.

[0004] At present, the application research of phytosterols in animal husbandry mainly focuses on pigs and poultry. There are few reports on the application research of phytosterols and emulsified phytosterols in rabbits. How to prepare emulsified phytosterols and determine the appropriate additive dosage are the difficulties in phytosterol research. Summary of the invention

[0005] The purpose of the present invention is to provide an emulsified phytosterol for improving the quality of white rabbit and a preparation method and application thereof, so as to solve the problems raised in the above background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme: an emulsified phytosterol for improving the quality of white rabbit and a preparation method and application thereof, comprising the following steps: S1. Raw material preparation: ordinary plant sterols are used as raw materials, sucrose esters are used as emulsifiers and pure water is used as water phase; S2, heating and oil phase pretreatment: adding phytosterols and sucrose esters into the oil phase and heating them to fully dissolve them; S3. Preparation of water phase: In another container, add pure water and water-soluble emulsifier; S4, oil-water mixing: slowly add the heated oil phase into the water phase and start stirring at a low speed to ensure that the oil and water are evenly mixed; S5. Emulsification treatment: Use a high shear emulsifier to emulsify at an appropriate speed to form a stable emulsion; S6, cooling and stabilization: After the emulsification is completed, continue stirring and gradually cool the emulsion to room temperature; S7. Product testing: The particle size of the emulsion is tested by particle size test, and then the thermal stability test is performed to ensure that the emulsion does not stratify or precipitate during storage and transportation. Finally, the pH value and viscosity of the emulsion are checked.

[0007] Preferably, in step S2, sucrose ester is added in an amount of 2.0-3.0%.

[0008] Preferably, the water-soluble emulsifier in step S3 is one of glycerol and propylene glycol, and the temperature of the water phase is controlled at 60°C-70°C.

[0009] Preferably, in step S5, the emulsification time is 30 to 50 minutes and the temperature is 30 to 50°C.

[0010] Preferably, the pH value of the emulsion checked in step S7 is controlled within the range of 5.5-7.0.

[0011] An emulsified phytosterol prepared by the above preparation method.

[0012] The present invention also provides application of the emulsified phytosterol in a feed additive for improving the quality of white rabbits.

[0013] Compared with the prior art, the present invention has the following beneficial effects: The invention uses phytosterol as a raw material, uses 2.0-3.0% sucrose ester as an emulsifier, performs emulsification for 30-50 minutes, and has an emulsification temperature of 30-50° C. The invention optimizes the preparation process conditions of the emulsified phytosterol, and determines the most suitable addition dosage in white rabbit feeding as a feed additive, which can provide a theoretical reference for feed industry production.

[0014] The emulsified phytosterol product prepared by the present invention can be used as a feed additive in feeding white rabbits, and is added to the diet at a ratio of 10 to 40 mg / kg to promote growth and improve the quality of rabbit meat. A feeding experiment was conducted on 40-day-old Fujian white rabbits for 60 days. Compared with a control group fed with a conventional diet, the diarrhea rate and mortality rate of the Fujian white rabbits in the emulsified phytosterol test group were significantly reduced, and various performance indicators such as average daily feed intake, average daily weight gain, feed-to-weight ratio, antioxidant activity, immune performance, slaughter performance and muscle quality were all increased or improved to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the preparation process of the present invention. DETAILED DESCRIPTION

[0016] In order to further explain the technical solution of the present invention, it is described in detail below through specific embodiments.

[0017] Embodiment 1 See also Figure 1 The present invention provides an emulsified phytosterol for improving the quality of white rabbits and a preparation method and application thereof, comprising the following steps: S1. Raw material preparation: ordinary plant sterols are used as raw materials, sucrose esters are used as emulsifiers and pure water is used as water phase; S2, heating and oil phase pretreatment: adding phytosterols and 2.5% sucrose esters into the oil phase and heating them to fully dissolve them; S3. Preparation of water phase: In another container, add pure water and water-soluble emulsifier (glycerin, propylene glycol, etc.), and control the temperature of the water phase at 60°C-70°C; S4, oil-water mixing: slowly add the heated oil phase into the water phase and start stirring at a low speed to ensure that the oil and water are evenly mixed; S5. Emulsification treatment: Use a high shear emulsifier to emulsify at an appropriate speed, the emulsification time is 40 minutes, the temperature is 40°C, and a stable emulsion is formed; S6, cooling and stabilization: After the emulsification is completed, continue stirring and gradually cool the emulsion to room temperature to further improve the stability of the emulsion; S7. Product testing: The particle size of the emulsion is tested by particle size test, and then the thermal stability test is performed to ensure that the emulsion does not stratify or precipitate during storage and transportation. Finally, the pH value (controlled in the range of: 5.5-7.0) and viscosity of the emulsion are checked.

[0018] Fermentation finished product performance testing: Feeding effect: After a feeding experiment with 40-day-old Fujian White rabbits for 60 days, compared with the control group fed with conventional diet, the diarrhea rate of Fujian White rabbits in the emulsified phytosterol group decreased from 13.3% to 3.3%, and the mortality rate decreased from 6.7% to 0; the average daily feed intake, average daily weight gain, and feed-to-weight ratio increased by 2.68%, 11.11%, and 8.90%, respectively; the MDA content and the activities of GSH-PX and CAT increased by 191.89%, 350.11%, and 62.32%, respectively; the concentrations of IgA, IgM, and IgG increased by 19.48%, 32.98%, and 21.79%, respectively; the full and half evisceration rates increased by 0.55% and 2.10%, respectively.

[0019] Embodiment 2 The present invention provides an emulsified phytosterol for improving the quality of white rabbits and a preparation method and application thereof, comprising the following steps: S1. Raw material preparation: ordinary plant sterols are used as raw materials, sucrose esters are used as emulsifiers and pure water is used as water phase; S2, heating and oil phase pretreatment: adding phytosterols and 2.0% sucrose esters into the oil phase and heating them to fully dissolve them; S3. Preparation of water phase: In another container, add pure water and water-soluble emulsifier (glycerin, propylene glycol, etc.), and control the temperature of the water phase at 60°C-70°C; S4, oil-water mixing: slowly add the heated oil phase into the water phase and start stirring at a low speed to ensure that the oil and water are evenly mixed; S5. Emulsification treatment: Use a high shear emulsifier to emulsify at an appropriate speed, the emulsification time is 30 minutes, the temperature is 50°C, and a stable emulsion is formed; S6, cooling and stabilization: After the emulsification is completed, continue stirring and gradually cool the emulsion to room temperature to further improve the stability of the emulsion; S7. Product testing: The particle size of the emulsion is tested by particle size test, and then the thermal stability test is performed to ensure that the emulsion does not stratify or precipitate during storage and transportation. Finally, the pH value (controlled in the range of: 5.5-7.0) and viscosity of the emulsion are checked.

[0020] Fermentation finished product performance testing: Feeding effect: After a feeding experiment with 40-day-old Fujian White rabbits for 60 days, compared with the control group fed with conventional diet, the diarrhea rate of Fujian White rabbits in the test group fed with emulsified phytosterols decreased from 13.3% to 3.3%, and the mortality rate decreased from 6.7% to 0; the average daily feed intake, average daily weight gain, and feed-to-weight ratio increased by 1.44%, 6.18%, and 5.46%, respectively; the MDA content and the activities of GSH-PX and CAT increased by 189.19%, 230.01%, and 57.82%, respectively; the concentrations of IgA, IgM, and IgG increased by 16.21%, 15.76%, and 5.13%, respectively; the full and half evisceration rates increased by 0.35% and 1.27%, respectively.

[0021] Embodiment 3 The present invention provides an emulsified phytosterol for improving the quality of white rabbits and a preparation method and application thereof, comprising the following steps: S1. Raw material preparation: ordinary plant sterols are used as raw materials, sucrose esters are used as emulsifiers and pure water is used as water phase; S2, heating and oil phase pretreatment: adding phytosterols and 3.0% sucrose esters into the oil phase and heating them to fully dissolve them; S3. Preparation of water phase: In another container, add pure water and water-soluble emulsifier (glycerin, propylene glycol, etc.), and control the temperature of the water phase at 60°C-70°C; S4, oil-water mixing: slowly add the heated oil phase into the water phase and start stirring at a low speed to ensure that the oil and water are evenly mixed; S5. Emulsification treatment: Use a high shear emulsifier to emulsify at an appropriate speed, the emulsification time is 50 minutes, the temperature is 30°C, and a stable emulsion is formed; S6, cooling and stabilization: After the emulsification is completed, continue stirring and gradually cool the emulsion to room temperature to further improve the stability of the emulsion; S7. Product testing: The particle size of the emulsion is tested by particle size test, and then the thermal stability test is performed to ensure that the emulsion does not stratify or precipitate during storage and transportation. Finally, the pH value (controlled in the range of: 5.5-7.0) and viscosity of the emulsion are checked.

[0022] Fermentation finished product performance testing: Feeding effect: After a feeding experiment with 40-day-old Fujian White rabbits for 60 days, compared with the control group fed with conventional diet, the diarrhea rate of Fujian White rabbits in the test group fed with emulsified phytosterols decreased from 13.3% to 6.7%, and the mortality rate decreased from 6.7% to 0; the average daily feed intake, average daily weight gain, and feed-to-weight ratio increased by 0.48%, 3.12%, and 4.25%, respectively; the MDA content and the activities of GSH-PX and CAT increased by 113.51%, 176.02%, and 22.12%, respectively; the concentrations of IgA, IgM, and IgG increased by 10.12%, 9.75%, and 2.56%, respectively; the full and half evisceration rates increased by 0.13% and 0.77%, respectively.

[0023] The following is the test method for adding emulsified phytosterols to feed: Test materials: the total sterol mass fraction in common phytosterols is ≥95%; the total sterol mass fraction in emulsified phytosterols is ≥40%, which is made by using common phytosterols as raw materials and sucrose esters as emulsifiers after emulsification treatment. The process parameters are as follows: adding 2.4% emulsifier, emulsifying for 40 min, and the emulsification temperature is 40 ℃.

[0024] The experimental animals were 150 healthy Fujian white rabbits (half male and half female) of similar weight, 40 days old, purchased from the Fujian White Rabbit Ecological Breeding Farm in Wudong Town, Wuping County at the age of 35 days. The experiment began after being raised for 5 days.

[0025] Feeding method: 150 healthy Fujian white rabbits of similar weight were randomly divided into 5 groups, 30 rabbits in each group (half male and half female), and kept in rabbit metabolism cages, 1 rabbit in each cage. The control group was fed a basic diet, and the experimental group A added 20 mg / kg of ordinary plant sterols to the basic diet. The experimental groups B to D added 10, 20 and 40 mg / kg of emulsified plant sterols to the basic diet, respectively. The experimental period was 60 days. The rabbits were fed with complete pellet feed, fed in the morning and evening every day, and had free access to nipple drinkers. Feeding management and immunization procedures were carried out as usual. The composition and nutritional level of the basic diet are shown in Table 1: Table 1 Basic diet composition and nutritional level (dry matter basis) Table 1 The premix provides per kg of feed: CaHPO4 15,000mg, NaCl 5,000mg, VA 8,000IU, VD 3800IU, VE 50mg, VK 31.5mg, thiamine 2mg, VB 120.02mg, riboflavin 5mg, pantothenic acid 15mg, niacin 50mg, folic acid 0.5mg, biotin 0.2mg, choline chloride 600mg, Fe80mg, Zn80mg, Cu20mg, Mn50mg, I0.5mg, Se0.03mg, Co1mg, and the rest are supplemented by carriers.

[0026] The digestible energy is the calculated value, and the rest are measured values.

[0027] Index determination and methods Determination of serum antioxidant enzyme activity and immune performance: At the end of the experiment, 10 healthy rabbits with similar weight were randomly selected from each group, blood was collected from the heart, and the serum was separated and stored for testing. Malondialdehyde (MDA), glutathione peroxidase (GSH-PX), catalase (CAT) and serum immunoglobulin IgA, IgG, and IgM levels were determined using kits provided by Nanjing Jiancheng Bioengineering Research Institute.

[0028] Determination of slaughter performance: At the end of the experiment, 10 healthy rabbits with similar weight were randomly selected from each group and slaughtered according to the method of Liu Lang et al.

[10] . The live weight, eviscerated weight and half-eviscerated weight were weighed before slaughter, and the eviscerated slaughter rate and half-eviscerated slaughter rate were calculated. The eviscerated weight is the carcass weight after slaughter without blood, fur, head and tail, limbs (below the wrist and tarsal joints) and internal organs; the half-eviscerated weight is the eviscerated weight plus the carcass weight of the heart, liver, kidneys and abdominal fat. The calculation formulas for relevant indicators are as follows: Eviscerated slaughter rate (%) = (eviscerated weight / live weight before slaughter) × 100 Eviscerated slaughter rate (%) = (Eviscerated weight / Live weight before slaughter) × 100 Meat quality: Meat quality was measured on an empty stomach after slaughtering in the early morning of the day when the experiment was completed, according to the method of Liu Lang et al.

[0029] Chroma: 45 min and 24 h after slaughter, a CHROMA METER CR-410 colorimeter was directly inserted into the cut meat samples (longissimus dorsi and biceps femoris) to measure the brightness (L*), redness (a*), and yellowness (b*) values. The results were repeated three times and the average value was taken.

[0030] pH: The pH of muscles (longissimus dorsi and biceps femoris) was directly measured using a Testo205 portable acidity meter 45 min and 24 h after slaughter. The results were repeated 3 times and the average value was taken.

[0031] Cooked meat rate: Take the longissimus dorsi and biceps femoris 1 to 2 hours after slaughter, remove the adventitia and surrounding fat, and weigh them (W1). Put the muscle sample in a preheated constant temperature water bath and heat it at 100 ℃ for 30 min. After taking it out, let it stand for 30 minutes to return to room temperature, then dry it and weigh it (W2).

[0032] Cooked meat rate (%) = (W2 / W1) × 100 Drip loss: Collect the rabbit back and leg muscles, remove the muscle membrane and surrounding fat, and record the weight (W3). Use a hook to fix the meat sample along the muscle fiber direction, store it in a refrigerator at 4°C, hang it in the refrigerator for one day, wipe the surface moisture with filter paper, and then weigh it (W4).

[0033] Drip loss (%) = [(W3-W4) / W3] × 100 Shear force: The muscle was trimmed into a size of 1 cm × 0.5 cm, and its outer membrane and attached fat were peeled off. The shear force value was measured using a C-LM3B digital muscle tenderizer.

[0034] Cooking loss: Store the meat sample in a refrigerator at 4℃ for one day, take it out and return it to room temperature, and weigh it (W5). After sealing, put it in a water bath and heat it at 80℃ until the temperature inside the sample is not lower than 70℃. Take it out and dry it, cool it for half an hour after draining the liquid, and take out the sample and weigh it (W6).

[0035] Cooking loss (%) = ((W5-W6) / W5] × 100 Data statistical analysis: Excel 2010 and SPSS 17.0 statistical software were used to process and analyze the data, and one-way ANOVA, Waller-Duncan and LSD tests were used to test the significance of differences between groups. Data are expressed as mean ± standard error, and P < 0.05 was considered significant.

[0036] Results and Analysis Effects of different amounts of emulsified phytosterols on antioxidant enzymes in Fujian white rabbits: As shown in Table 2, the MDA content of the experimental groups A, C, and D were significantly lower than that of the control group (P<0.05); the GSH-PX activity values ​​of the experimental groups C and D tended to increase compared with the control group, but the difference was not significant (P>0.05); the CAT activity values ​​of the experimental groups C and D were significantly higher than those of the control group (P<0.05).

[0037] Table 2 Effects of different amounts of emulsified phytosterols on antioxidant enzymes in Fujian white rabbits Data in the same column with different lowercase letters indicate significant differences (P<0.05), and data with the same letters indicate no significant differences (P>0.05).

[0038] Effects of different amounts of emulsified phytosterols on the immune function of Fujian white rabbits: As shown in Table 3, the IgA content in the serum of rabbits in the experimental groups A, B, and C showed an increasing trend compared with the control group (P<0.05), but the difference was not significant; the IgG and IgM content in the serum of rabbits in the experimental group C was significantly higher than that in the control group (P<0.05); the IgG and IgM content in the serum of rabbits in the experimental groups A, B, and D were not significantly different from those in the control group (P>0.05).

[0039] Table 3 Effects of different amounts of emulsified phytosterols on the immune function of Fujian white rabbits Data in the same column with different lowercase letters indicate significant differences (P<0.05), and data with the same letters indicate no significant differences (P>0.05).

[0040] Effects of different amounts of emulsified phytosterols on the slaughter performance of Fujian White rabbits: As shown in Table 4, compared with the control group, there were no significant differences in the eviscerated slaughter rate and semi-eviscerated slaughter rate of the experimental groups A, B, C, and D (P>0.05).

[0041] Table 4 Effects of different amounts of emulsified phytosterols on slaughter performance of Fujian White rabbits Data in the same row with different lowercase letters indicate significant differences (P<0.05), and data with the same lowercase letters indicate no significant differences (P>0.05).

[0042] Effects of different amounts of emulsified phytosterols on muscle quality of Fujian white rabbits: As shown in Table 5, compared with the control group, the 45-minute longissimus dorsi muscle color of the experimental groups C and D was significantly reduced (P<0.05); the pH value of the dorsal muscle of the experimental group D was significantly increased (P<0.05); the cooking loss of the experimental group D was significantly reduced (P<0.05); there were no significant differences in the cooked meat rate, drip loss and shear force among the experimental groups (P>0.05).

[0043] Table 5 Effects of different amounts of emulsified phytosterols on muscle quality of Fujian white rabbits Data in the same row with different lowercase letters indicate significant differences (P<0.05), and data with the same lowercase letters indicate no significant differences (P>0.05).

[0044] Effects of different amounts of emulsified phytosterols on antioxidant enzymes in Fujian white rabbits: Malondialdehyde (MDA) is a common oxidative stress marker, produced by the peroxidation of unsaturated fatty acids, which can indirectly reflect the degree of lipid peroxidation in the body, and can reflect the body's ability to scavenge free radicals and the degree of damage to free radicals. The results of this experiment show that adding 20 mg / kg of ordinary plant sterols and 20 mg / kg and 40 mg / kg of emulsified plant sterols to the diet can significantly reduce the MDA level and peroxidation of the liver and longissimus dorsi muscle, and reduce the damage of MDA to the body. This result is similar to the research results of Bai Jian et al.

[0045] Glutathione peroxidase (GSH-Px) can reflect the body's ability to resist peroxidation. The results of this experiment show that adding 20mg / kg and 40mg / kg of emulsified plant sterols to the diet has an increasing trend compared with the control group, promoting peroxide reduction, thereby reducing the content of MDA and improving the body's antioxidant level.

[0046] Zhu Annan et al. found that CAT has strong antioxidant properties, and its main function is to catalyze hydrogen peroxide to produce water and oxygen, thereby reducing the damage caused by hydrogen peroxide to the body. The results of this experiment show that adding 20mg / kg and 40mg / kg of emulsified plant sterols to the diet can increase the content of catalase, strengthen the body's inhibition of hydrogen peroxide, make it decompose rapidly, reduce the content of malondialdehyde, and improve the body's antioxidant level. This also further confirms that the addition of emulsified plant sterols has a strong antioxidant capacity and helps to enhance the antioxidant defense mechanism of white rabbits.

[0047] Effects of different amounts of emulsified phytosterols on the immune function of Fujian white rabbits: Lin Boquan and others found that immunoglobulin, as the main antibody regulating humoral immunity in the body's immunity, is an important indicator for measuring the body's immune function. The results of this experiment showed that the IgA content in the serum of the experimental groups A, B, and C tended to increase compared with the control group, promoting the body to produce IgA; the IgA content in the serum of the white rabbits in the experimental group D tended to decrease compared with the control group. The experiment showed that excessive emulsified plant sterols would inhibit the body from producing IgA. The IgG content in the serum of the experimental group C was significantly higher than that in the control group, and the IgG content in the serum of the white rabbits in the experimental groups A, B, and D tended to decrease compared with the control group. The IgM content in the serum of the white rabbits in the experimental groups A, B, and D tended to decrease compared with the control group, and the IgM content in the serum of the white rabbits in the experimental group C tended to increase compared with the control group. Therefore, adding 20 mg / kg (experimental group C) of emulsified plant sterols alone to the diet can improve the immune performance of Fujian white rabbits, which is similar to the research results of Xia Yingzi et al.

[0048] Effects of different amounts of emulsified phytosterols on slaughter performance and meat quality of Fujian White rabbits: Slaughter performance and meat quality are important indicators of the economic value of meat livestock and poultry. Zou Shenglong et al. found that plant sterols had no significant effect on the slaughter rate, half-eviscerated rate and full-eviscerated rate of fast-growing yellow chickens, which is consistent with the results of this experiment. The addition of emulsified plant sterols had no significant effect on the half-eviscerated rate and full-eviscerated rate of Fujian white rabbits. The research results of Zhang Yi et al. showed that supplementing plant sterols in beef cattle feed can significantly reduce drip loss and cooking loss, and can also improve color, but has no significant effect on the pH value and shear force of the longissimus dorsi muscle. In this experiment, the redness and yellowness of test group A were higher than those of other groups, and the color of test groups C and D was lower. This shows that a certain concentration of plant sterols can increase the content and proportion of hemoglobin, deoxymyoglobin, oxymyoglobin and metmyoglobin deposition in Fujian white rabbit muscles, but the highly absorbed emulsified plant sterols have an inhibitory effect. The pH value of the experimental group D increased. The appropriate pH value is beneficial to improving the flavor of the muscle, restoring the water retention of the muscle, and increasing the taste. Conventional indicators for evaluating the water retention capacity of meat include drip loss, cooked meat rate, and cooking loss. The cooking loss of the experimental group D was significantly lower than that of the control group, which shows that the emulsified plant sterols have a positive effect on the water retention capacity of rabbit meat, making the rabbit meat juicy and more flavorful. A higher concentration of emulsified plant sterols improves the water retention of rabbit meat, but at the same time it also has a negative impact on the color. This shows that the concentration of suitable emulsified plant sterols needs to be further explored.

[0049] Test results: According to the test results, adding 20 mg / kg of ordinary plant sterols and 20 and 40 mg / kg of emulsified plant sterols to the diet can reduce the concentration of MDA. Adding 20 mg / kg and 40 mg / kg of emulsified plant sterols to the diet alone has an increasing trend compared with the control group. Adding 20 and 40 mg / kg of emulsified plant sterols to the diet can increase CAT activity. Therefore, adding 20 and 40 mg / kg of emulsified plant sterols to the diet has an improving effect on the antioxidant enzymes of Fujian White Rabbits.

[0050] In the experiment, adding 20mg / kg of common phytosterols and 10 and 20mg / kg of emulsified phytosterols to the diet alone tended to increase the IgA content; adding 20mg / kg of emulsified phytosterols to the diet alone increased the IgG content; adding 20mg / kg of emulsified phytosterols to the diet alone tended to increase the IgM content. Therefore, adding 20mg / kg of emulsified phytosterols to the diet has the most obvious effect on improving the immune performance of Fujian White Rabbits.

[0051] The above description is only a preferred example of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing emulsified phytosterols for improving the quality of white rabbit, characterized in that: The following steps are involved: S1. Raw material preparation: ordinary plant sterols are used as raw materials, sucrose esters are used as emulsifiers and pure water is used as water phase; S2, heating and oil phase pretreatment: adding phytosterols and sucrose esters into the oil phase and heating them to fully dissolve them; S3. Preparation of water phase: In another container, add pure water and water-soluble emulsifier; S4, oil-water mixing: slowly add the heated oil phase into the water phase and start stirring at a low speed to ensure that the oil and water are evenly mixed; S5. Emulsification treatment: Use a high shear emulsifier to emulsify at an appropriate speed to form a stable emulsion; S6, cooling and stabilization: After the emulsification is completed, continue stirring and gradually cool the emulsion to room temperature; S7. Product testing: The particle size of the emulsion is tested by particle size test, and then the thermal stability test is performed to ensure that the emulsion does not stratify or precipitate during storage and transportation. Finally, the pH value and viscosity of the emulsion are checked.

2. A method for preparing emulsified phytosterols for improving the quality of white rabbit according to claim 1, characterized in that: In the step S2, sucrose ester is added at 2.0-3.0%.

3. The method for preparing an emulsified phytosterol for improving the quality of white rabbit according to claim 1, characterized in that: The water-soluble emulsifier in step S3 is one of glycerol and propylene glycol, and the temperature of the water phase is controlled at 60°C-70°C.

4. The method for preparing emulsified phytosterols for improving the quality of white rabbit according to claim 1, characterized in that: In step S5, the emulsification time is 30 to 50 minutes and the temperature is 30 to 50°C.

5. The method for preparing emulsified phytosterols for improving the quality of white rabbit according to claim 1, characterized in that: In step S7, the pH value of the emulsion is checked to be controlled within the range of 5.5-7.

0.

6. An emulsified phytosterol prepared by the preparation method according to any one of claims 1 to 5.

7. Use of the emulsified phytosterol according to claim 6 in a feed additive for improving the quality of white rabbits.

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