Compound antioxidant feed additive as well as preparation method and application thereof

Abstract

The invention discloses a compound antioxidant feed additive as well as a preparation method and application thereof, and belongs to the technical field of feed additives. According to the additive, ethoxyquin and butylated hydroxytoluene are used as anti-oxidation and heat-stable components, rutin and zeaxanthin are used as light-stable components, high-purity phytic acid is creatively added to realize targeted chelation of metal ions, all the components have a synergistic effect, and the problems of high-temperature granulation decomposition, illumination oxidation and metal ion catalytic rancidity of feed are effectively solved. The compound feed is reasonable in formula, simple and convenient in process, low in cost, obviously superior to conventional products in light and heat stability and antioxidant effect, suitable for livestock and poultry and aquatic products, and good in industrial application value.

Description

Technical Field

[0001] This invention belongs to the field of feed additive technology, specifically relating to a compound antioxidant feed additive, its preparation method, and its application. Background Technology

[0002] With the large-scale development of livestock, poultry, and aquaculture, high-oil compound feeds are highly susceptible to oxidative rancidity during storage, transportation, and high-temperature pelleting. This not only reduces the nutritional value of the feed but also produces harmful substances that affect animal health. Currently, commonly used single or simple compound antioxidants such as ethoxyquinoline and butylated hydroxytoluene, while possessing certain antioxidant effects, are prone to volatilization and decomposition under high-temperature pelleting conditions and photodegradation during long-term storage under light, resulting in insufficient antioxidant stability. Furthermore, metal ions such as Fe3+ and Cu2+ in feed significantly accelerate oil oxidation, and conventional antioxidants lack targeted chelating capabilities, making it difficult to achieve comprehensive antioxidant protection.

[0003] Existing compound antioxidants mostly focus on basic antioxidant formulations, and generally suffer from problems such as weak high-temperature resistance, poor photostability, and insufficient metal ion inhibition effect, failing to simultaneously meet the stability requirements of high-temperature granulation, light-induced storage, and metal ion catalytic environments. Therefore, developing a highly efficient compound antioxidant that integrates thermal stability, photostability, and metal ion chelation, and achieving synergistic effects through rational component formulation, is of great significance for improving feed shelf life and ensuring the quality of aquatic products. Summary of the Invention

[0004] To address the problems of existing feed additives being easily decomposed at high temperatures, easily oxidized by light, lacking metal ion chelating ability, and having insufficient synergistic effects, this invention proposes a composite antioxidant feed additive and its preparation method. This additive, through a specific ratio of components such as ethoxyquinoline and high-purity phytic acid, and a stepwise temperature-controlled process design, overcomes the limitations of single-system formulations, simultaneously achieving excellent thermal stability, light stability, and metal chelating properties. The process is simple, cost-controllable, and suitable for compound feeds for livestock, poultry, and aquatic products.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A compound antioxidant feed additive, said additive is prepared from the following raw materials in parts by weight: The mixture comprises 20-50 parts of ethoxyquinoline, 10-30 parts of butylated hydroxytoluene, 5-15 parts of rutin, 3-10 parts of zeaxanthin, 5-15 parts of high-purity phytic acid, 0.3-1.5 parts of natural vitamin E, and 10-30 parts of a carrier; wherein the high-purity phytic acid has a purity ≥98%, and the weight ratio of ethoxyquinoline to high-purity phytic acid is 3.5:1-4:1.

[0006] Optionally, the carrier is one or more of diatomaceous earth, zeolite powder and maifanite powder, and the particle size of the carrier is 100-200 mesh.

[0007] Optionally, the natural vitamin E forms a synergistic photostable system with rutin and zeaxanthin, resulting in an antioxidant activity retention rate of 85-92% for the feed after 60 days of light exposure.

[0008] Optionally, the preparation method of the aforementioned compound antioxidant feed additive includes the following specific preparation steps: S1. Pulverize ethoxyquinoline, butylated hydroxytoluene, rutin, and zeaxanthin to 80-100 mesh, pass them through an 80-mesh standard sieve, and set them aside. Place the high-purity phytic acid at 25-30℃ for 10-15 minutes to eliminate low-temperature crystallization. Dry the carrier at 105-110℃ for 2-3 hours and cool it to room temperature before use. S2. Weigh high-purity phytic acid and butylated hydroxytoluene, add them to a double planetary mixer, control the stirring speed at 250~300 r / min, and mix for 25~30 min at 35~40℃ and 50-60% humidity to form a stable chelate precursor. S3. Add pretreated ethoxyquinoline, rutin, zeaxanthin and natural vitamin E to the chelation precursor. Heat the mixer to 45~50℃, maintain the stirring speed at 300~350r / min, and continue stirring for 30~40min. During this period, take a sample every 10min to check the mixing uniformity. Stop when the uniformity is ≥95%. S4. Add the pretreated carrier to the mixture obtained in S3, adjust the stirring speed to 350~400r / min, and stir for 40~60min at room temperature and humidity of 50-60%. After mixing, filter through a 100~120 mesh sieve to remove impurities, and the compound antioxidant feed additive product is obtained.

[0009] Optionally, the speed ratio of the impellers in the dual planetary mixers in S2 and S3 is 2:1, and nitrogen protection is used during the mixing process.

[0010] Optionally, after filtering and removing impurities in step S4, the finished product is further subjected to low-temperature drying: drying temperature 35~45℃, drying time 1~2h, and the moisture content of the finished product is controlled to be ≤8%.

[0011] Optionally, the compound feed for livestock and poultry is early-stage compound feed for piglets, compound feed for broilers during the fattening period, or compound feed for laying hens during the peak egg production period; the amount of additive added to the compound feed for livestock and poultry is 0.15% to 0.18%.

[0012] Optionally, the aquatic compound feed is tilapia juvenile compound feed or Litopenaeus vannamei adult shrimp compound feed; the additive is added to the aquatic compound feed at a rate of 0.18% to 0.2%.

[0013] Optionally, after pelleting at 95°C, the antioxidant activity retention rate of the feed with the added additive is ≥92%; after storage at 25°C and light intensity of 100μW / cm2 for 30 days, the feed peroxide value is ≤4.5mmol / kg and the acid value is ≤2.5mg KOH / g; after storage for 60 days, the antioxidant activity retention rate is 85~92%.

[0014] The beneficial effects of this invention are: This invention utilizes a multi-component synergistic compounding and stepwise temperature-controlled preparation process to enable antioxidants to possess excellent thermal stability, light stability, and metal ion chelating ability. This effectively solves problems such as easy decomposition during high-temperature pelleting, easy oxidation during light storage, and accelerated rancidity caused by metal ions. After pelleting at 95℃, the product retains ≥92% of its antioxidant activity, and after 60 days of light exposure, the activity retention rate reaches 85-92%. The feed peroxide value is ≤4.5 mmol / kg, and the acid value is ≤2.5 mg KOH / g. The antioxidant effect and storage stability are significantly superior to traditional formulations. Furthermore, the preparation process is simple, the raw materials are readily available, and the cost is controllable. The added amount of the finished product is only 0.15%-0.2%, making it widely applicable to livestock, poultry, and aquatic compound feeds, and possessing significant industrial application value. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0016] Example 1: This Example 1 describes a compound antioxidant feed additive, prepared from the following raw materials in parts by weight: Ethoxyquinoline (EQ) 35 parts, butylated hydroxytoluene 20 parts, rutin 10 parts, zeaxanthin 6 parts, high-purity phytic acid 10 parts, natural vitamin E 0.8 parts, and carrier 20 parts (diatomaceous earth: zeolite powder = 1.5:1). This embodiment 1 describes a compound antioxidant feed additive, which is prepared from the following raw materials in parts by weight: S1. Ethoxyquinoline, butylated hydroxytoluene, rutin, and zeaxanthin are pulverized to 90 mesh and passed through an 80-mesh standard sieve for later use. The high-purity phytic acid is placed at 28°C for 12 minutes in advance to eliminate low-temperature crystallization. The carrier is pulverized to 150 mesh and passed through a 100-mesh standard sieve. The carrier is then dried at 108°C for 2.5 hours and cooled to room temperature for later use. S2. Weigh high-purity phytic acid and butylated hydroxytoluene, add them to a double planetary mixer (mixing speed ratio of 2:1), introduce nitrogen into the mixer for protection, control the mixing speed at 280 r / min, and mix for 28 min at 38℃ and 55% humidity to form a stable chelate precursor. S3. Add pretreated ethoxyquinoline, rutin, zeaxanthin and natural vitamin E to the chelation precursor. Heat the mixer to 48°C and maintain the stirring speed at 320r / min for 35min. Take a sample every 10min to check the mixing uniformity. Stop when the uniformity reaches 96%. S4. Add the pretreated carrier to the mixture obtained in S3, adjust the stirring speed to 380 r / min, and stir for 50 min at room temperature and 55% humidity. After mixing, filter through a 110-mesh sieve to remove impurities. After filtration, place the finished product at 40℃ for low-temperature drying for 1.5 h, and control the moisture content of the finished product to 4.2%, thus obtaining the compound antioxidant feed additive product.

[0017] Example 2: This Example 2 describes a compound antioxidant feed additive, prepared from the following raw materials in parts by weight: EQ 37 parts, butylated hydroxytoluene 20 parts, rutin 10 parts, zeaxanthin 6 parts, high-purity phytic acid 10 parts, natural vitamin E 0.8 parts and carrier 18 parts (diatomaceous earth: zeolite powder = 1.5:1); The preparation method of the compound antioxidant feed additive in Example 2 is the same as that in Example 1, except that the amount of EQ is increased to 37 parts.

[0018] Example 3: This Example 3 describes a compound antioxidant feed additive, prepared from the following raw materials in parts by weight: EQ 35 parts, butylated hydroxytoluene 20 parts, rutin 10 parts, zeaxanthin 6 parts, high-purity phytic acid 10 parts, natural vitamin E 1.2 parts, and carrier 20 parts (diatomaceous earth: zeolite powder = 1.5:1). The preparation method of the compound antioxidant feed additive in Example 3 is the same as that in Example 1, except that the amount of natural vitamin E is increased to 1.2 parts.

[0019] Comparative Example 1: The additive in Comparative Example 1 was prepared from the following parts by weight of raw materials: EQ 35 parts, butylated hydroxytoluene 20 parts, rutin 10 parts, zeaxanthin 6 parts, natural vitamin E 0.8 parts and carrier 30 parts (diatomaceous earth: zeolite powder = 1.5:1); The preparation method of the additives in this comparative example is the same as that in Example 1, except that high-purity phytic acid is not added.

[0020] Comparative Example 2: The additive in Comparative Example 2 was prepared from the following parts by weight of raw materials: EQ 35 parts, butylated hydroxytoluene 20 parts, rutin 10 parts, zeaxanthin 6 parts, high-purity phytic acid 10 parts, carrier 20.8 parts (diatomaceous earth: zeolite powder = 1.5:1); The preparation method of the additives in this comparative example is the same as that in Example 1, except that natural vitamin E is not added.

[0021] Comparative Example 3: The additive in Comparative Example 3 was prepared from the following parts by weight of raw materials: EQ 35 parts, butylated hydroxytoluene 20 parts, zeaxanthin 6 parts, high-purity phytic acid 10 parts, natural vitamin E 0.8 parts and carrier 30 parts (diatomaceous earth: zeolite powder = 1.5:1); The preparation method of the additives in this comparative example is the same as that in Example 1, except that rutin is not added.

[0022] Performance testing 1. Antioxidant activity retention rate test The compound antioxidant feed additives from the examples and comparative examples were mixed into the basal feed at a dosage of 0.18%, and divided into two experimental groups: one group was granulated at 95℃ (simulating industrial feed production process), and after cooling to room temperature, the antioxidant activity values ​​of the original feed before granulation and the feed after granulation were measured using the DPPH free radical scavenging method, and the retention rate was calculated; the other group was stored at 25℃ and light intensity of 100μW / cm2 for 60 days, and the antioxidant activity values ​​of the feed at the beginning of storage (day 0) and after 60 days of storage were measured and the retention rate was calculated. During the test, the antioxidant components in the feed were extracted by anhydrous ethanol, and the absorbance was measured at a wavelength of 517nm. A standard curve was plotted using vitamin C as a standard substance to calibrate the test results. Three parallel samples were set for each group of samples, and the average value was taken to ensure the accuracy and repeatability of the data.

[0023] Table 1. Test data on the retention rate of antioxidant activity of different samples

[0024] Examples 1-3 showed an activity retention rate of over 93% after granulation at 95℃, and a retention rate of 88.3%-91.6% after 60 days of light exposure, all significantly better than the comparative examples. This indicates that the compound system of the present invention can not only improve thermal stability to adapt to industrial granulation, but also inhibit activity decay under light exposure through the synergistic effect of light-stabilizing components, ensuring antioxidant effects during production and storage.

[0025] 2. Determination of feed peroxide value (POV) The composite antioxidants from the examples and comparative examples were uniformly mixed into the basic compound feed at an addition rate of 0.18%. After mixing, the mixture was stored at 25°C and under a light intensity of 100 μW / cm² for 30 days. 20g of the stored sample was crushed, and the fat in the feed was extracted by reflux with petroleum ether. The extract was then evaporated by rotary evaporation to remove the solvent, yielding crude fat. The crude fat sample was dissolved in a mixture of chloroform and glacial acetic acid (volume ratio 2:3), and 1mL of saturated potassium iodide solution was added. After reacting in the dark for 5 minutes, 75mL of distilled water was added and the mixture was shaken well. Using 1% starch solution as an indicator, the solution was titrated with 0.01mol / L sodium thiosulfate standard solution until the blue color disappeared and did not recover within 30 seconds. A blank control was also performed. The peroxide value (unit: mmol / kg) was calculated based on the titration volume. Three parallel samples were set up for each group, and the average value was taken as the test result.

[0026] Table 2. Data on peroxide value determination of different feed samples

[0027] The peroxide values ​​of the feeds corresponding to Examples 1-3 were all below 3.3 mmol∙kg⁻¹, significantly lower than the 4.0-4.7 mmol∙kg⁻¹ of the comparative examples. This result confirms that the additive of the present invention can effectively block the chain reaction of fat oxidation, reduce peroxide formation, and significantly inhibit feed oxidative rancidity, thus extending the shelf life of the feed.

[0028] 3. Determination of feed acid value (AV) The composite antioxidants from the examples and comparative examples were uniformly mixed into the basic compound feed at an addition rate of 0.18%. After mixing, the mixture was stored at 25°C and a light intensity of 100 μW / cm² for 30 days. The stored sample was then crushed, and the fat in the feed was extracted by reflux with petroleum ether. The extract was then evaporated by rotary evaporation to remove the solvent, yielding crude fat. 2g of crude fat was weighed and placed in an Erlenmeyer flask, dissolved in a neutral ether-ethanol mixture, and titrated with 0.1mol / L potassium hydroxide standard solution using phenolphthalein as an indicator until the solution turned slightly red and did not fade within 30s. The volume of potassium hydroxide consumed was recorded, and a blank test was performed simultaneously. The acid value was calculated according to the formula. Three parallel samples were set up for each group, and the average value was taken as the test result.

[0029] Table 3. Data on acid value (AV) determination of different feed samples

[0030] The acid value of the feed in Examples 1-3 was controlled at 1.7-1.9 mg KOH∙g⁻¹, which is much lower than the 2.3-2.7 mg KOH∙g⁻¹ of the comparative example. This indicates that the additive of the present invention can not only inhibit fat oxidation, but also delay fat hydrolysis and reduce the generation of free fatty acids, thus providing dual protection for feed quality and avoiding a decline in palatability and nutritional value.

[0031] 4. Finished product stability test 50g of each of the composite antioxidant feed additives from Examples 1-3 and Comparative Examples 1-3 were placed in sealed, moisture-proof polyethylene bags and stored for 6 months at a constant temperature and humidity of 25°C and 60% relative humidity. Samples were taken at the beginning of storage (day 0), 3 months, and 6 months for testing. The moisture content was determined by the drying method (5g of sample was weighed and dried in an oven at 105°C until constant weight, and the moisture percentage was calculated). The bulk density was measured using a bulk density meter, and the angle of repose was measured using an angle of repose meter to evaluate flowability. The agglomeration of the samples was observed (whether agglomeration occurred and the hardness of the agglomeration were recorded). Three parallel samples were set for each group of samples, and the average value was taken as the test result to comprehensively verify the stability and practicality of the finished product during long-term storage, transportation, and use.

[0032] Table 4. Stability test data of different finished samples after 6 months of storage

[0033] After 6 months of storage, the finished products in Examples 1-3 had a moisture content of 4.1%-4.3%, a bulk density of 0.71-0.73 g / mL, an angle of repose ≤36°, and no clumping. In contrast, the comparative examples had higher moisture content, poorer flowability, and slight clumping. This demonstrates that the finished products of this invention maintain stable physical properties and usability during long-term storage and transportation, exhibiting good practical application value.

[0034] 5. Performance verification tests in different application scenarios Add 0.15% to the early stage compound feed for piglets, 0.18% to the compound feed for broilers during the fattening period, 0.17% to the compound feed for laying hens during their peak egg production period, 0.20% to the compound feed for juvenile tilapia, and 0.19% to the compound feed for adult whiteleg shrimp. Three parallel samples were set up for each group. The test method was the same as the above-mentioned methods for determining the antioxidant activity retention rate, peroxide value, and acid value. That is, after granulation and cooling at 95℃, the DPPH free radical scavenging method (absorbance measured at 517nm wavelength, calibrated with vitamin C standard curve) was used to determine the activity retention rate after granulation. The feed was stored at 25℃ and light intensity of 100μW / cm2 for 30 days and 60 days respectively. After 30 days of storage, the peroxide value and acid value were determined by the corresponding titration method. After 60 days of storage, the antioxidant activity retention rate was determined by the same DPPH method. The average value of the parallel samples was taken as the final test result.

[0035] Table 5. Test data for verifying the effectiveness of Example 1 in different application scenarios.

[0036] Example 1 demonstrates that the additive of this invention can achieve stable antioxidant effects in various livestock, poultry, and aquatic compound feeds, and all indicators meet the scope defined in the claims, indicating that the additive of this invention has a wide range of applications and strong adaptability in dosage. It can effectively inhibit oxidative rancidity in different feeds and has good practical application value.

[0037] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A compound antioxidant feed additive, characterized in that, The additive is prepared from the following raw materials in parts by weight: The mixture comprises 20-50 parts of ethoxyquinoline, 10-30 parts of butylated hydroxytoluene, 5-15 parts of rutin, 3-10 parts of zeaxanthin, 5-15 parts of high-purity phytic acid, 0.3-1.5 parts of natural vitamin E, and 10-30 parts of a carrier; wherein the high-purity phytic acid has a purity ≥98%, and the weight ratio of ethoxyquinoline to high-purity phytic acid is 3.5:1-4:

1.

2. The compound antioxidant feed additive according to claim 1, characterized in that, The carrier is one or more of diatomaceous earth, zeolite powder and maifanite powder, and the particle size of the carrier is 100~200 mesh.

3. The compound antioxidant feed additive according to claim 1, characterized in that, The natural vitamin E, together with rutin and zeaxanthin, forms a synergistic photostable system, resulting in an antioxidant activity retention rate of 85-92% for the feed after 60 days of light exposure.

4. A method for preparing a compound antioxidant feed additive, used to prepare a compound antioxidant feed additive as described in any one of claims 1 to 3, characterized in that, The specific preparation steps are as follows: S1. Pulverize ethoxyquinoline, butylated hydroxytoluene, rutin, and zeaxanthin to 80-100 mesh, pass them through an 80-mesh standard sieve, and set them aside. Place the high-purity phytic acid at 25-30℃ for 10-15 minutes to eliminate low-temperature crystallization. Dry the carrier at 105-110℃ for 2-3 hours and cool it to room temperature before use. S2. Weigh high-purity phytic acid and butylated hydroxytoluene, add them to a double planetary mixer, control the stirring speed at 250~300 r / min, and mix for 25~30 min at 35~40℃ and 50-60% humidity to form a stable chelate precursor. S3. Add pretreated ethoxyquinoline, rutin, zeaxanthin and natural vitamin E to the chelation precursor. Heat the mixer to 45~50℃, maintain the stirring speed at 300~350r / min, and continue stirring for 30~40min. During this period, take a sample every 10min to check the mixing uniformity. Stop when the uniformity is ≥95%. S4. Add the pretreated carrier to the mixture obtained in S3, adjust the stirring speed to 350~400r / min, and stir for 40~60min at room temperature and humidity of 50-60%. After mixing, filter through a 100~120 mesh sieve to remove impurities, and the compound antioxidant feed additive product is obtained.

5. The method for preparing a compound antioxidant feed additive according to claim 4, characterized in that, The speed ratio of the impellers in the dual planetary mixers in S2 and S3 is 2:1, and nitrogen protection is used during the mixing process.

6. The method for preparing a compound antioxidant feed additive according to claim 4, characterized in that, After filtering and removing impurities in step S4, the finished product is further subjected to low-temperature drying: drying temperature 35~45℃, drying time 1~2h, and the moisture content of the finished product is controlled to be ≤8%.

7. The application of a compound antioxidant feed additive according to any one of claims 1 to 3 in livestock and poultry compound feed, characterized in that, The compound feed for livestock and poultry is early-stage compound feed for piglets, compound feed for broilers during the fattening period, or compound feed for laying hens during their peak egg production period; the amount of additive added to the compound feed for livestock and poultry is 0.15% to 0.18%.

8. The application of a compound antioxidant feed additive according to any one of claims 1 to 3 in aquatic compound feed, characterized in that, The aquatic compound feed is a compound feed for juvenile tilapia and a compound feed for adult whiteleg shrimp; the additive is added to the aquatic compound feed at a rate of 0.18% to 0.2%.

9. The application of a compound antioxidant feed additive according to any one of claims 7-8, characterized in that, After pelleting at 95°C, the antioxidant activity retention rate of feed with the additive is ≥92%; after storage at 25°C and light intensity of 100μW / cm2 for 30 days, the peroxide value of the feed is ≤4.5mmol / kg and the acid value is ≤2.5mg KOH / g; after storage for 60 days, the antioxidant activity retention rate is 85~92%.

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