A compound feed for improving the redness of cooked river crab shell and crab paste and a preparation method thereof

Abstract

This invention relates to the field of feed technology and provides a compound feed and preparation method for enhancing the redness of cooked river crab shells and crab roe. The feed comprises the following raw materials by weight percentage: fish meal 25-32%, defatted soybean 8-12%, blood meal 3-5%, cottonseed meal 3-5%, cottonseed meal enzymatically hydrolyzed protein 0.8-1.6%, peanut meal 16-20%, rapeseed meal 1.5-2.5%, α-starch 18-22%, soybean lecithin oil 2.5-4.0%, fish oil 1-2%, calcium dihydrogen phosphate 1.2%-1.5%, zeolite powder 0.6-1.0%, compound premix 1%, capsanthin 0.5-1.0%, zeaxanthin 0.3-0.5%, natural astaxanthin 0.1-0.2%, bile acids 0.5%, and ethoxyquinoline 0.5%. This invention utilizes the strong emulsifying properties of phospholipids to improve the bioavailability of carotenoids and enhance the redness of the hepatopancreas and crab shell; it also utilizes the phospholipid components rich in soybean phospholipid oil to promote the development of crab gonads, increase the volume of crab roe (hepatopancreas and gonads), and further enhance the overall visual redness of the crab roe through pigment accumulation during gonad development.

Description

Technical Field

[0001] This invention belongs to the field of feed technology, and in particular relates to a compound feed and its preparation method for improving the redness of cooked river crab shells and crab roe. Background Technology

[0002] In the quality evaluation of Chinese mitten crabs (river crabs), the redness of the cooked body color (shell) and the color of the crab roe (hepatopancreas and gonads) are the core indicators determining its market price. The red color of the crab roe and shell comes from carotenoids (astaxanthin, which plays a major role, is also a carotenoid). Carotenoids are fat-soluble, and their degree of emulsification in the intestines directly determines their absorption rate. The development and maturation of the gonads require a large amount of phospholipids. The better the gonads develop, the fuller the crab roe. At the same time, the gonads are also important organs for the deposition of carotenoids, and the degree of gonad development directly affects the depth of the orange-red color of the cooked crab roe.

[0003] Most river crabs currently available on the market that are farmed using feed have the following drawbacks:

[0004] Crab roe not fully developed: Ordinary feed does not provide sufficient support for gonad development in the later stages of fattening, resulting in less crab roe;

[0005] The crab roe and shell have a dull color: The contribution of gonadal development to the color of crab roe was not considered. Simply supplementing with carotenoids resulted in low absorption rate, leading to poor redness saturation after cooking.

[0006] Resource waste: Carotenoids are expensive and added in large quantities, but they cannot be effectively utilized by crabs due to the lack of emulsifying carriers (such as soybean lecithin oil). Summary of the Invention

[0007] The purpose of this invention is to provide a formulated feed that enhances the redness of the shell and roe of cooked river crabs, thereby addressing the problems mentioned in the background section.

[0008] The present invention is implemented as follows: a compound feed for enhancing the redness of cooked river crab shells and crab roe comprises the following raw materials by weight percentage: fish meal 25-32%, defatted soybean 8-12%, blood meal 3-5%, cottonseed meal 3-5%, cottonseed meal enzymatically hydrolyzed protein 0.8-1.6%, peanut meal 16-20%, rapeseed meal 1.5-2.5%, α-starch 18-22%, soybean lecithin oil 2.5-4.0%, fish oil 1-2%, calcium dihydrogen phosphate 1.2%-1.5%, zeolite powder 0.6-1.0%, compound premix 1%, capsanthin 0.5-1.0%, zeaxanthin 0.3-0.5%, natural astaxanthin 0.1-0.2%, bile acids 0.5%, and ethoxyquinoline 0.5%.

[0009] Another objective of this invention is to provide a method for preparing a compound feed that enhances the redness of the shell and roe of cooked river crabs, comprising the following steps:

[0010] 1) Crush fish meal, defatted soybeans, blood meal, cottonseed meal, enzymatically hydrolyzed cottonseed meal, peanut meal, rapeseed meal, calcium dihydrogen phosphate, and zeolite powder separately, and then put them into a mixer in sequence for stirring and mixing.

[0011] 2) Pre-mix α-starch, compound premix, capsanthin, zeaxanthin, natural astaxanthin, bile acid, and ethoxyquinoline, and then pour them into a mixer as a whole and continue to stir and mix with the already mixed raw materials.

[0012] 3) Heat the soybean lecithin oil to 40-50℃, mix it with the fish oil, shake well, pour it into a spray bottle, and spray it evenly onto the raw materials that have been mixed in step 2).

[0013] 4) Add water and continue stirring to mix well to obtain the feed mixture;

[0014] 5) Use a single-screw pellet mill to make feed pellets from the feed mixture;

[0015] 6) Use a constant temperature dryer to dehydrate, cool and dry the feed pellets to control their moisture content.

[0016] This invention employs a composite pigment scheme, combining capsanthin, zeaxanthin, and astaxanthin in a specific ratio to enhance the color of cooked crabs. Soybean lecithin oil is used as a carrier to promote gonadal development and improve pigment absorption. 2.5-4% soybean lecithin oil acts as a bioavailability enhancer for carotenoids, strengthening pigment deposition in the hepatopancreas and shell. Simultaneously, soybean lecithin oil promotes gonadal development in crabs, further improving the crab roe richness. Furthermore, soybean lecithin oil increases the total fat level and phospholipid content of the crab roe, improving the taste and color after cooking. Bile acids are added to enhance the utilization rate of soybean lecithin by the crabs. During preparation, a specific spraying and mixing temperature (40-50℃) is used to control the flowability of the lecithin oil, and specific conditioning (80-85℃) and drying processes are employed to ensure its stability.

[0017] The river crabs cultured using the feed of this invention have the following advantages compared to existing technologies:

[0018] The crab roe was fuller: the degree of gonadal development was significantly improved, and the weight of the crab roe (hepatopancreas + gonads) increased by 10-15% compared with the conventional group;

[0019] Cooking results in a redder color: the a* value (redness) of the crab shell and crab roe is significantly increased, presenting a bright red visual characteristic;

[0020] High nutrient utilization rate: The emulsifying effect of soybean phospholipid oil significantly increases the deposition rate of fat-soluble pigments in tissues, thereby increasing the redness of crab roe;

[0021] Strong pricing power: The farmed crabs are "full of roe and bright red", which is significantly better than ordinary feed sold in the market, thus increasing the unit price. Attached Figure Description

[0022] Figure 1 The color difference data and images of crab shells in the experimental group and the control group provided for the embodiments of the present invention (* indicates P < 0.05, the crab on the left is the experimental group, and the crab on the right is the control group).

[0023] Figure 2 The color difference data and images of crab roe in the experimental group and the control group provided in the embodiments of the present invention (* indicates P < 0.05, the crab on the left is the control group, and the crab on the right is the experimental group); Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the 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 merely illustrative and not intended to limit the invention.

[0025] The compound premix used in this embodiment of the invention contains per kilogram: Vitamin A 900,000 IU, Vitamin D 200,000 IU, Vitamin E 4,500 mg, Vitamin K 3,220 mg, Vitamin B1 3,200 mg, Vitamin B2 1,090 mg, Vitamin B5 2,000 mg, Vitamin B6 5,000 mg, and Vitamin B1. 12 1.6 mg, Vitamin C 5000 mg, Pantothenic Acid 1000 mg, Folic Acid 165 mg, Choline 60000 mg; Contains minerals: Copper Sulfate 2.0 g, Ferric Sulfate 25 g, Zinc Sulfate 22 g, Manganese Sulfate 7 g, Sodium Selenite 0.04 g, Potassium Iodide 0.026 g, Cobalt Chloride 0.1 g.

[0026] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0027] Example 1: A compound feed for enhancing the redness of cooked river crab shells and crab roe, with the following ingredient ratios: fish meal 30%, defatted soybean 10%, blood meal 4%, cottonseed meal 3.12%, cottonseed meal enzymatically hydrolyzed protein 0.8%, peanut meal 18.81%, rapeseed meal 2%, α-starch 21.01%, soybean lecithin oil 3.55%, fish oil 1%, calcium dihydrogen phosphate 1%, zeolite powder 0.9%, compound premix 1%, capsanthin (a carotenoid) 1%, zeaxanthin (a carotenoid) 0.5%, natural astaxanthin (a carotenoid derived from Haematococcus pluvialis powder) 0.2%, bile acids 0.5%, and ethoxyquinoline 0.5%. It contains the following nutrients and levels: dry matter 89.9%, moisture 10%, crude protein 40%, crude fat 7.5%, crude ash 11.5%, and crude fiber 4.5%.

[0028] Prepare according to the following steps:

[0029] 1) Weigh out the various feed ingredients according to the weight percentage requirements of each ingredient;

[0030] 2) Crush fish meal, defatted soybeans, blood meal, cottonseed meal, cottonseed meal enzymatic protein, peanut meal, rapeseed meal, calcium dihydrogen phosphate, zeolite powder and other raw materials separately. The particle size requirement is that all raw materials pass through an 80-mesh sieve and the weight percentage of the material on a 100-mesh sieve is not greater than 15%. Then put them into a mixer in sequence for stirring and mixing.

[0031] 3) Pre-mix α-starch, compound premix, capsanthin, zeaxanthin, natural astaxanthin, bile acid, and ethoxyquinoline, and then pour them into a mixer as a whole and continue to mix with the raw materials already mixed in step 2).

[0032] 4) Heat the soybean lecithin oil to 40-50℃, mix it with the fish oil, shake well, pour it into a spray bottle, and spray it evenly onto the raw materials that have been mixed in step 3).

[0033] 5) Add a certain proportion of water, the amount of water being 30% of the total weight of all components in step 1), and continue to stir and mix for 5 minutes to obtain the feed mixture;

[0034] 6) Use a single-screw pellet mill to make the above mixture into feed pellets with a particle size of 0.5-3mm and a length of 0.8-2cm;

[0035] 7) Use a constant temperature dryer to dehydrate, cool and dry the feed pellets at 30℃ for 40 minutes. The moisture content of the feed pellets should be controlled at 9-11%. The above moisture content is by mass percentage and is based on the air-dried sample.

[0036] Example 2: A formulated feed for enhancing the redness of cooked river crab shells and crab roe, prepared as follows:

[0037] 1) Take 3 kg of fish meal, 1 kg of defatted soybeans, 0.4 kg of blood meal, 0.312 kg of cottonseed meal, 0.08 kg of enzymatically hydrolyzed cottonseed meal protein, 1.881 kg of peanut meal, 0.2 kg of rapeseed meal, 2.101 kg of α-starch, 0.355 kg of soybean lecithin oil, 0.1 kg of fish oil, 0.09 kg of zeolite powder, 0.1 kg of compound premix, 0.1 kg of capsanthin, 0.05 kg of zeaxanthin, 0.02 kg of natural astaxanthin, 0.05 kg of bile acids, and 0.05 kg of ethoxyquinoline; it contains the following nutrients: 89.9% dry matter, 10% moisture, 40% crude protein, 7.5% crude fat, 11.5% crude ash, and 4.5% crude fiber;

[0038] 2) Crush fish meal, defatted soybeans, blood meal, cottonseed meal, cottonseed meal enzymatic protein, peanut meal, rapeseed meal, calcium dihydrogen phosphate, zeolite powder and other raw materials separately. The particle size requirement is that all raw materials pass through an 80-mesh sieve and the weight percentage of the material on a 100-mesh sieve is not greater than 15%. Then put them into a mixer in sequence for stirring and mixing.

[0039] 3) Pre-mix α-starch, compound premix, capsanthin, zeaxanthin, natural astaxanthin, bile acid, and ethoxyquinoline, and then pour them into a mixer as a whole and continue to mix with the raw materials already mixed in step 2).

[0040] 4) Heat the soybean lecithin oil to 45°C, mix it with the fish oil, shake well, pour it into a spray bottle, and spray it evenly onto the raw materials that have been mixed in step 3).

[0041] 5) Add a certain proportion of water, the amount of water being 35% of the total weight of all components in step 1), and continue to stir and mix for 5 minutes to obtain the feed mixture;

[0042] 6) Use a single-screw pellet mill to make the above mixture into feed pellets with a particle size of 0.5-3mm and a length of 0.8-2cm;

[0043] 7) Dehydrate, cool, and dry using a constant temperature dryer at 37℃ for 30 minutes. The moisture content of the feed pellets should be controlled at 9-11%; the above moisture content is by mass percentage, based on an air-dried sample.

[0044] Example 3 differs from Example 1 in that the weight percentages of each raw material are as follows: fish meal 28%, defatted soybean 12%, blood meal 3%, cottonseed meal 4.12%, cottonseed meal enzymatic protein 0.8%, peanut meal 17.81%, rapeseed meal 3%, α-starch 20.01%, soybean lecithin oil 4.55%, fish oil 1%, calcium dihydrogen phosphate 0.9%, zeolite powder 1%, compound premix 0.9%, capsanthin (a carotenoid) 1.1%, zeaxanthin (a carotenoid) 0.6%, natural astaxanthin (a carotenoid derived from Haematococcus pluvialis powder) 0.1%, bile acids 0.6%, and ethoxyquinoline 0.41%.

[0045] Example 4 differs from Example 1 in that the weight percentages of each raw material are as follows: fish meal 32%, defatted soybean 8%, blood meal 2.5%, cottonseed meal 4.62%, cottonseed meal enzymatically hydrolyzed protein 0.6%, peanut meal 18.01%, rapeseed meal 2.8%, α-starch 20.21%, soybean lecithin oil 4.05%, fish oil 1.5%, calcium dihydrogen phosphate 0.8%, zeolite powder 1.1%, compound premix 1.1%, capsanthin (a carotenoid) 0.9%, zeaxanthin (a carotenoid) 0.5%, natural astaxanthin (a carotenoid derived from Haematococcus pluvialis powder) 0.2%, bile acids 0.7%, and ethoxyquinoline 0.31%.

[0046] Example 5 differs from Example 1 in that the weight percentages of each raw material are as follows: fish meal 25%, defatted soybean 15%, blood meal 2%, cottonseed meal 4.62%, cottonseed meal enzymatically hydrolyzed protein 1.1%, peanut meal 16.01%, rapeseed meal 4.8%, α-starch 20.21%, soybean lecithin oil 3.05%, fish oil 2.5%, calcium dihydrogen phosphate 1.5%, zeolite powder 0.4%, compound premix 1%, capsanthin (a carotenoid) 1.2%, zeaxanthin (a carotenoid) 0.1%, natural astaxanthin (a carotenoid derived from Haematococcus pluvialis powder) 0.3%, bile acids 0.6%, and ethoxyquinoline 0.31%.

[0047] Aquaculture trials and analysis of results:

[0048] The aquaculture experiment was conducted in white plastic buckets (75cm × 55cm × 45cm). The crabs used in the experiment were bred by Tianchang Yanghuzha Aquatic Products Harvesting Co., Ltd. After temporary holding, 80 crabs of uniform size and with the same molting cycle (initial weight: 40.45 ± 0.21 g) were randomly captured from the same crab pond and randomly divided into 8 white plastic buckets, with 10 crabs in each bucket. The aquaculture experiment included two groups: an experimental group and a control group, with 4 replicates in each group. The experimental group was fed the compound feed prepared in Example 1 to enhance the redness of the cooked crab shell and crab roe, while the control group was fed commercial crab feed with the same protein level (purchased from Huaibei Tianpeng Feed Co., Ltd., product name: Jinpeng Crab Extruded Compound Feed). The experiment period was from the end of May to the end of July. During the experiment, the feeding and mortality of the crabs in the white plastic buckets were observed and recorded. One-third of the water was changed every 3 days. After the aquaculture was completed, the crabs were weighed and dissected to collect samples for physiological and biochemical data analysis. The specific group information is shown in Table 1.

[0049] Table 1 Grouping

[0050]

[0051] The growth performance of the river crabs after 8 weeks of cultivation is shown in Table 2:

[0052] Table 2. Growth performance data of crab farming experiment

[0053]

[0054] All data are presented as mean ± standard error (n=4). Crab roe fat content was determined using a Soxhlet extractor (based on fresh samples). Other indicators were calculated using the following formulas:

[0055] Survival rate (%) = Number of surviving crabs × 100% / Number of crabs released into the wild;

[0056] Weight gain rate (%) = (final weight - initial weight) × 100% / initial weight;

[0057] Feed conversion ratio = Feed intake / (Final body weight - Initial body weight);

[0058] Gonadal / Hepatopancreatic Index (%) = Tissue weight / Body weight × 100%;

[0059] Crab roe index (%) = (gona weight + hepatopancreas weight) / body weight × 100%;

[0060] As shown in Table 2, the survival rate, weight gain rate, and hepatopancreas index of the experimental group were higher than those of the control group, while the feed conversion ratio showed the opposite difference, but none of them showed significant differences (P > 0.05). This indicates that the survival rate, growth rate, and nutrient deposition of the crabs were not affected after using the formulated feed prepared in Example 1 to enhance the redness of the cooked crab shell and crab roe. It is worth noting that the gonad index, crab roe index, and fat content of the crab roe in the experimental group showed a significant upward trend compared with the control group (P < 0.05). This fully verifies the technological advancement of the present invention in using soybean phospholipid oil to replace ordinary soybean oil, that is, the strong emulsifying properties of phospholipids significantly promote gonad development and lipid accumulation. In addition, the experimental group maintained a good hepatopancreas index while significantly improving the roe-enriching effect. This reflects that the present invention is more scientific and reasonable in terms of raw material selection and nutrient ratio than commercially available ordinary feed, which is of great significance for improving the economic benefits of crab farming.

[0061] Comparison of color differences between crab shells and crab roe in the experimental and control groups. Figure 1 , Figure 2 As shown, by Figure 1 and Figure 2 It can be seen that the redness (a*) values ​​of the shell and crab roe of the cooked crabs in the experimental group showed a significant upward trend compared with those in the control group (P < 0.05). This directly verifies the significant effect of the feed in the present invention on the targeted regulation of the sensory quality of crabs; among which... Figure 1 The dramatic increase in the redness of the crab shells is mainly attributed to the scientifically formulated blend of capsanthin, zeaxanthin, and natural astaxanthin in the feed. Furthermore, soybean lecithin oil, through its strong emulsifying properties, significantly enhances the bioavailability of these fat-soluble pigments in the crab's intestines, enabling their efficient deposition in the carapace tissue. Figure 2 The increased redness of the crab roe reflects the synergistic effect of pigment deposition and gonadal development. Soybean phospholipid oil not only serves as an excellent carrier for pigments but also directly drives the rapid development of gonads and lipid accumulation. As the volume of the crab roe increases, the color saturation significantly enhances with the increase in pigment accumulation and fat content. This synchronous improvement in body color and crab roe is highly consistent with the data on the increase in gonadal index and fat content in Table 2. It fully demonstrates the core competitive advantage of the phospholipid carrier and compound carotenoid pigment combination technology used in this invention in enhancing the visual appeal and market premium of cooked river crabs. Its targeted optimization effect on quality is significantly better than that of commercially available conventional river crab feed.

[0062] The above description is merely 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 within the protection scope of the present invention.

Claims

1. A formulated feed for enhancing the redness of cooked river crab shells and crab roe, characterized in that, The ingredients include the following percentages by weight: fish meal 25-32%, defatted soybeans 8-12%, blood meal 3-5%, cottonseed meal 3-5%, cottonseed meal enzymatically hydrolyzed protein 0.8-1.6%, peanut meal 16-20%, rapeseed meal 1.5-2.5%, α-starch 18-22%, soybean lecithin oil 2.5-4.0%, fish oil 1-2%, calcium dihydrogen phosphate 1.2%-1.5%, zeolite powder 0.6-1.0%, compound premix 1%, capsanthin 0.5-1.0%, zeaxanthin 0.3-0.5%, natural astaxanthin 0.1-0.2%, bile acids 0.5%, and ethoxyquinoline 0.5%.

2. The formulated feed for enhancing the redness of cooked river crab shells and crab roe according to claim 1, characterized in that, The compound premix contains vitamins A, D, E, K3, B1, B2, B5, B6, and B6. 12 Vitamin C, pantothenic acid, folic acid, choline, copper sulfate, ferric sulfate, zinc sulfate, manganese sulfate, sodium selenite, potassium iodide, and cobalt chloride.

3. A method for preparing a compound feed to enhance the redness of cooked river crab shells and roe as described in claim 1 or 2, characterized in that, Includes the following steps: 1) Crush fish meal, defatted soybeans, blood meal, cottonseed meal, enzymatically hydrolyzed cottonseed meal, peanut meal, rapeseed meal, calcium dihydrogen phosphate, and zeolite powder separately, and then put them into a mixer in sequence for stirring and mixing. 2) Pre-mix α-starch, compound premix, capsanthin, zeaxanthin, natural astaxanthin, bile acid, and ethoxyquinoline, and then pour them into a mixer as a whole and continue to stir and mix with the already mixed raw materials. 3) Heat the soybean lecithin oil to 40-50℃, mix it with the fish oil, shake well, pour it into a spray bottle, and spray it evenly onto the raw materials that have been mixed in step 2). 4) Add water and continue stirring to mix well to obtain the feed mixture; 5) Use a single-screw pellet mill to make feed pellets from the feed mixture; 6) Use a constant temperature dryer to dehydrate, cool and dry the feed pellets to control their moisture content.

4. The method for preparing compound feed to enhance the redness of cooked river crab shells and crab roe according to claim 3, characterized in that, In step 1), all the crushed raw materials are passed through an 80-mesh sieve, and the weight percentage of the raw materials on the 100-mesh sieve is no more than 15%.

5. The method for preparing compound feed to enhance the redness of cooked river crab shells and crab roe according to claim 3, characterized in that, In step 4), the amount of water added is 30-35% of the total weight of all raw materials.

6. The method for preparing compound feed to enhance the redness of cooked river crab shells and crab roe according to claim 3, characterized in that, In step 5), the feed pellets have a diameter of 0.5-3 mm and a length of 0.8-2 cm.

7. The method for preparing compound feed to enhance the redness of cooked river crab shells and crab roe according to claim 3, characterized in that, In step 6), the drying temperature is 30-37℃ and the time is 30-40 minutes; The moisture content is 9-11%.

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