A method of making, formulation and use of a functional pet treat

Abstract

The application discloses a preparation method, formula and application of functional pet snacks, and relates to the technical field of functional pet snack preparation. Lotus root starch is dispersed in distilled water, shark chondroitin is added into the dispersion, then xanthan gum and whole egg powder are added into the mixed system, magnetic stirring is carried out until the mixture is uniformly mixed, then the mixed solution is placed into a water bath kettle for gelatinization, and after cooling to room temperature, the mixed solution is loaded into a printer cartridge, and then is transferred into a 4 DEG C refrigerator for recrystallization for 12 hours to obtain functional pet snack raw materials. After the raw materials are taken out and cooled to room temperature, a 3D printer is used to prepare the functional pet snacks. The obtained functional pet snacks have the effects of improving immunity and resisting arthritis, and have important academic value and application prospect.

Description

Technical Field

[0001] This invention relates to the field of functional pet snack technology, specifically to a method of preparing a hydrogel raw material using lotus root starch and xanthan gum as raw materials, adding whole egg powder and shark chondroitin, and using 3D printing technology to prepare functional pet snacks, in order to achieve functions such as relieving arthritis, lowering blood lipids, and anti-oxidation. Background Technology

[0002] In recent years, with the rapid development of the global economy and the continuous updating of people's consumption concepts, my country's pet economy has risen rapidly. While people pay attention to their own dietary nutrition and health, they have also begun to pay more attention to the nutrition and health of their pets. With the upgrading of domestic pet demand and the increasing awareness of scientific feeding concepts among pet owners, pet food is no longer limited to simply providing satiety. Current research focuses more on the different nutritional needs of different breeds, ages, and functional pets, and the development of diversified functional pet foods has become a major direction for pet food development. Functional pet snacks differ from traditional pet food; they are pet snacks with added special functional additives and specific health benefits. They are developed for specific pets that need to supplement certain nutrients or improve bodily functions. Although they cannot directly act like medicine, they can enhance health to a certain extent.

[0003] Functional pet snacks mainly include the following types: dental cleaning snacks (which help clean pets' teeth, reduce plaque and tartar formation, and thus maintain oral health); gastrointestinal health snacks (containing probiotics and fiber, which can help improve the health of pets' digestive system); skin and coat health snacks (rich in Omega-3 and Omega-6 fatty acids, which can help improve the health of pets' skin and coat); and joint protection snacks (containing antioxidants, tocopherols, and sulfides, which help reduce inflammation). Although there are many types of pet snacks, the product forms are relatively simple, with most being meat products, which can easily lead to excessive fat intake, which is not good for the health of older and obese pets. Joint protection pet snacks are mostly in the form of tablets, pastes, and granules, and these products have many drawbacks. Tablet products are simply a mixture of functional ingredients, granulated, and compressed into tablets, which does not play the necessary role in the dispersion and dissolution of the drug components. Moreover, tablets are relatively hard, making them difficult for older dogs and cats to chew and resulting in poor palatability. Ointment-based products have a high moisture content, making them highly susceptible to the growth of harmful microorganisms. They also suffer from drawbacks such as unstable active ingredients, difficulty in preservation, easy spoilage, and bloating, as well as discoloration during storage. Granules require dissolving in water for use, but dogs and cats, especially cats, dislike drinking water and resist administering medication through drinking. Over time, their efficacy decreases, making them less effective. To address these shortcomings of existing functional pet treats, this invention utilizes 3D printing technology to customize food according to the specific needs of pets. It can create pet treats of various shapes and textures, not only increasing pets' appetite and interest but also providing specific functionality.

[0004] 3D printing, also known as additive manufacturing (FDM), is an emerging technology that uses computer-aided design (CAD) mathematical models to layer and stack raw materials. 3D printing technology reduces material usage, increases product yield, and creates entities with unique internal structures that are difficult to process using traditional methods. It has been recognized by *The Economist* as a technology that could drive the Third Industrial Revolution. Therefore, 3D printing technology is widely used in aerospace, machinery manufacturing, automotive, biomedicine, food, and art. Compared to traditional food modeling methods, food 3D printing technology offers advantages such as high energy efficiency, environmental friendliness, support for personalized customization, and improved nutritional balance. Using 3D printing technology, food can be precisely designed and produced by controlling the printing materials and nutrient content, meeting individual nutritional needs based on health status and physical activity. Common food printing inks include those for chocolate, candy, starch, and fruit pulp.

[0005] Starch has garnered widespread attention due to its wide availability and low price, playing an indispensable role in people's daily diet. Starch hydrogels, pseudoplastic fluids exhibiting shear-thinning behavior, are easily extruded under high-shear printing conditions and can be layered, demonstrating great potential in the field of 3D printing. Lotus root starch is a primary powdered product made from lotus root through processes such as peeling, cutting, color protection, homogenization, filtering, drying, and pulverizing. It retains the color and aroma of the lotus root flesh and preserves other natural components besides the peel, such as starch, flavonoids, vitamins, minerals, and asparagine. However, the poor performance of natural starch gels and the poor 3D printing results limit its application in the food and non-food processing industries. To meet higher consumer demands and expand the application range of natural starch, physical, chemical, and enzymatic methods are frequently used to modify natural starch. However, chemical modification leaves a large amount of chemical residues, and enzyme modification is very expensive. Hydrophilic colloid modified starch, as a common physical modification method, has received widespread attention due to its advantages such as being green, safe, and pollution-free.

[0006] Hydrophilic colloids are a class of food additives that function as thickeners, stabilizers, emulsifiers, and gellers. They are used in food processing and significantly improve the physicochemical properties of starch. Xanthan gum is an extracellular polysaccharide produced by the fermentation of *Xanthomonas campestris*. It consists of a glucose backbone and trisaccharide side chains, making it an anionic hydrophilic colloid. When dissolved in water, its side chains can wrap anti-wound around the cellulose backbone to form the primary structure of xanthan gum; intermolecular hydrogen bonds form a double helix structure, which is the secondary structure of xanthan gum; further, the double helix structures intertwine to form a network-like tertiary conformation. This unique molecular conformation determines its excellent emulsifying, thickening, thixotropic, and pseudoplastic properties, and it can interact with other polysaccharides (such as starch). It is also a safe, non-toxic, and environmentally friendly substance, making it one of the most superior hydrophilic colloids in the food industry both domestically and internationally.

[0007] Eggs contain almost all the nutrients an animal needs, with their most prominent feature being high-quality protein. Besides protein, eggs are also rich in calcium, phosphorus, iron, and vitamins. Egg powder, a novel edible egg product, is made from egg liquid after drying to remove moisture. Studies have shown that egg powder not only contains all the protein found in fresh eggs but also has the same nutritional value. Generally, egg powder is divided into whole egg powder, egg white powder, and egg yolk powder. Whole egg powder possesses excellent functional properties such as gelling, emulsifying, and water-retaining properties. Due to these functional characteristics, egg powder can be used as a food nutritional additive and quality improver. It not only improves the flavor of food but also enhances its nutritional value, and is widely used in the food processing industry.

[0008] Chondroitin sulfate (ChS) is a glycosaminoglycan widely found in animal connective tissues. It possesses various physiological functions, including relieving arthritis, lowering blood lipids, anti-oxidation, and anti-angiogenesis. It can also improve the flavor, texture, gloss, and moisturizing properties of food, making it widely applicable in food, medicine, and cosmetics, with broad development prospects. Studies have shown that shark cartilage is rich in ChS, and chondroitin sulfate extracted from shark cartilage has good therapeutic effects on many diseases, possessing high development and utilization value and currently being an important raw material source for chondroitin sulfate. Because chondroitin sulfate is easily hydrolyzed into monosaccharides or other smaller polysaccharides under acidic conditions, direct oral administration is easily degraded by gastric acid and digestive enzymes, affecting its absorption. Using lotus root starch hydrogel to load ChS can solve this problem.

[0009] As mentioned above, the application of 3D printing in the food industry has attracted increasing interest from researchers, but it is still in its early stages, especially in the area of ​​3D printing functional pet snacks, where research is extremely limited. Realizing 3D-printed functional pet snacks faces both challenges and opportunities. The purpose of this invention is to develop 3D-printed functional pet snacks that not only meet the demand for personalized customization and on-demand production, but also allow for the addition of functional ingredients (whole egg powder, shark cartilage extract) to the printing ink. This will create functional pet snacks that improve animal immunity, activate connective tissue, reduce joint inflammation, and delay aging, providing innovative ideas for pet food preparation. More importantly, this invention represents a breakthrough and exploratory research into the 3D printing technology for functional pet snacks, contributing to the development of 3D printing in the food industry. Summary of the Invention

[0010] Using lotus root starch and xanthan gum as blank gel matrices, functional ingredients were added to the gel matrices. Functional pet snacks were prepared using 3D printing technology. The study investigated the effects of different ratios of lotus root starch and xanthan gum on the 3D printing effect, as well as the effects of adding different concentrations of functional ingredients on the structural properties of the gel ink and the 3D printing effect, in order to obtain the optimal concentration ratio and thus the best printed product.

[0011] The functional pet treat formula of this invention is prepared from the following raw materials in parts by weight:

[0012] 1-20 parts lotus root starch

[0013] Xanthan gum 0.5-2 parts,

[0014] 0.5-2 parts whole egg powder,

[0015] Shark chondroitin 0.5-2 parts,

[0016] Make up to 100 servings with purified water.

[0017] The preferred functional pet treat formula is prepared from the following ingredients in parts by weight:

[0018] 15 parts lotus root starch

[0019] 1.5 parts xanthan gum

[0020] 1 portion of whole egg powder

[0021] 1.5 parts shark chondroitin

[0022] Make up to 100 servings with purified water.

[0023] The preparation method for functional pet treats is as follows:

[0024] (1) Lotus root starch was dispersed in purified water at a concentration of 15 wt%.

[0025] (2) Slowly add shark chondroitin to the starch solution and stir thoroughly to dissolve it completely;

[0026] (3) Add xanthan gum and whole egg powder to step (2) in sequence and stir thoroughly to make them evenly mixed;

[0027] (4) Place the mixed solution from step (3) into a water bath to gelatinize;

[0028] (5) Take out the gelatinized composite solution starch paste from step (4), let it cool naturally to room temperature, put it into the printer barrel, and then transfer it to a 4°C refrigerator for recrystallization to obtain functional pet snack raw materials.

[0029] (6) After cooling the pet treat ingredients in the hopper of step (5) to room temperature, use a 3D printer to 3D print them.

[0030] (7) The printed product obtained in step (6) is dried and then processed.

[0031] The preferred concentration of shark chondroitin in step (2) is 1.5 wt%.

[0032] In step (3), the preferred concentration of whole egg powder is 1 wt%; the concentration of xanthan gum is 1.5 wt%.

[0033] The gelatinization conditions in step (4) are 80°C for 40 minutes;

[0034] The recrystallization time in step (5) is 8-12 hours, preferably 12 hours;

[0035] The preferred 3D printer parameters mentioned in step (6) are: pressure 35PSI, syringe size 18G, and printing speed 30mm / s;

[0036] The drying method described in step (7) is: natural air drying or freeze drying, with freeze drying being the preferred drying method.

[0037] The above-mentioned method for preparing functional pet snacks can also be carried out by molding.

[0038] The aforementioned functional pet snacks are intended for use in pets such as dogs and cats to relieve joint inflammation and lower blood lipids.

[0039] The beneficial effects of this invention are as follows:

[0040] (1) In this invention, xanthan gum and lotus root starch are combined to prepare hydrogel as blank pet snack gel matrix. Both are natural polysaccharides, which are safe and reliable and can be used for consumption.

[0041] (2) The present invention uses 1% whole egg powder, which not only improves the 3D printing effect, but also has the functional properties of protein supplement, palatability enhancer and so on.

[0042] (3) In this invention, shark chondroitin is selected as a functional nutrient and added to a blank gel matrix to obtain a functional pet snack that can improve immunity and resist arthritis. Attached Figure Description

[0043] Figure 1 3D printing effect of hydrogels with different lotus root starch concentrations added according to the present invention;

[0044] Figure 2 , 34 represents the rheological properties of lotus root starch after adding different hydrophilic colloids in this invention;

[0045] Figure 5 The gel texture characteristics of lotus root starch after adding different hydrophilic colloids in this invention;

[0046] Figure 6 This is a microstructure diagram of lotus root starch hydrogel after adding different hydrophilic colloids in this invention;

[0047] Figure 7 The image shows the 3D printing effect of lotus root starch gel after adding different hydrophilic colloids in this invention.

[0048] Figure 8 The image shows the 3D printing effect of lotus root starch gel after adding different concentrations of whole egg powder in this invention.

[0049] Figure 9 Precision analysis of lotus root starch gel 3D printing after adding different concentrations of whole egg powder in this invention;

[0050] Figure 10 Color analysis of lotus root starch gel after adding different concentrations of whole egg powder and after 3D printing in this invention;

[0051] Figure 11 The rheological properties of lotus root starch gel after adding different concentrations of whole egg powder in this invention;

[0052] Figure 12 The electronic nose radar image of the compound system after adding different concentrations of whole egg powder in this invention;

[0053] Figure 13 This is a principal component analysis diagram of the compound system after adding different concentrations of whole egg powder in this invention.

[0054] Figure 14 This is the standard curve of shark chondroitin in this invention;

[0055] Figure 15 This invention provides a comparison of shark chondroitin loading rates.

[0056] Figure 16 Analysis of the 3D printing behavior of gel inks with different concentrations of shark chondroitin added in this invention;

[0057] Figure 17 This invention illustrates the impact of different post-processing methods on the quality of pet snacks.

[0058] Figure 18 The crispness index of pet snacks after different post-processing in this invention;

[0059] Figure 19 These are photographs of mice four weeks after intervention with functional pet snacks in this invention;

[0060] Figure 20 The degree of joint swelling in mice in this invention;

[0061] Figure 21 The values ​​represent the expression levels of IL-1β and IL-4 in mouse serum during this invention. Detailed Implementation

[0062] The terminology used in this invention, unless otherwise specified, will generally be understood by those skilled in the art. The invention is described in further detail below with reference to specific embodiments and data. It should be noted that these embodiments are merely illustrative and not intended to limit the scope of the invention in any way.

[0063] The lotus root starch used in this invention can be extracted from lotus roots themselves or purchased as a commercially available finished product.

[0064] The method for extracting starch from lotus root is as follows:

[0065] (1) Pretreatment of lotus root: Quickly wash fresh lotus root, remove sand, peel, weigh, cut into pieces, and soak in a mixed solution of 1% NaCl and 0.2% NaHSO3.

[0066] (2) Pulping (material-liquid ratio of 1:6), filtration: soak the filter residue in 0.05% NaOH solution for 40 minutes and then filter it, take the filtrate; then wash the filter residue with water twice and take the filtrate.

[0067] (3) Centrifuge all the filtrates at 4500 r / min for 10 min to obtain a white solid at the bottom of the centrifuge cup. Scrape off the dark impurities on the surface. Repeat the washing process three times to obtain wet starch. Place the wet starch in a 50℃ oven and dry it for 12 hours. Then grind it into powder using a pulverizer to obtain lotus root starch.

[0068] In the following embodiments of the present invention, the Chinese names, full English names, or abbreviations of the following terms may be used. Regardless of whether the Chinese name, full English name, or abbreviation is used, it represents a compound, drug, or reagent. See Table 1 for details:

[0069] Table 1. English-Chinese Abbreviation Table

[0070]

[0071] Experimental Example 1: Analysis of 3D Printing Behavior of Lotus Root Starch Hydrogels with Different Concentrations

[0072] plan:

[0073] Lotus root starch was dispersed in distilled water at concentrations of 5 wt%, 10 wt%, 15 wt%, and 20 wt%. After thorough stirring, the dispersions were placed in an 80°C water bath and gelatinized for 40 minutes while stirring. The gelatinized lotus root starch was then removed, allowed to cool naturally to room temperature, loaded into the printer cartridge, and then transferred to a 4°C refrigerator for recrystallization for 12 hours to obtain lotus root starch 3D printing raw material.

[0074] Measurement method:

[0075] The material canister was loaded into the printer, and a 18G printhead (G indicates that the outer diameter of the Gauge nozzle is 1.27 mm and the inner diameter is 0.84 mm) was used to perform 3D printing behavior analysis at a pressure of 35 PSI (PSI: pounds per square inch).

[0076] The 3D printing equipment used in this invention has been granted a national invention patent. For a detailed description, please refer to 202210947855.X, "A Multi-Frequency Ultrasonic Coupled Multi-Nozzle Food Additive Manufacturing Device and Method".

[0077] Results analysis:

[0078] Figure 1 The images show the 3D printing effects of hydrogels with different lotus root starch concentrations. As can be seen from the images, when the lotus root starch concentration is 0.5%, the hydrogel is difficult to shape, remaining close to a fluid state, which does not meet the requirements for 3D printing. When the concentration increases to 10%, the solid-like behavior of the hydrogel ink strengthens, but shape collapse is severe, resulting in poor forming effects. When the lotus root starch concentration is 15%, the hydrogel ink forms well, maintaining a roughly circular shape, showing potential for 3D printing. When the concentration reaches 20%, due to the excessively high starch concentration and strong solid-like behavior of the hydrogel, the ink is difficult to expel from the nozzle, resulting in poor forming effects and printing results. The results indicate that, in the 3D printing effect images, a lotus root starch concentration of 15% yields relatively better printing results.

[0079] Experiment Example 2: Effects of different hydrophilic colloids on the gelatinization and gel properties of lotus root starch

[0080] plan:

[0081] Based on the optimized results of Experiment Example 1, lotus root starch with a concentration of 15 wt% was dispersed in distilled water. Then, different types (XG, SA, GG, and GA) and different concentrations (0.5 wt%, 1.0 wt%, and 1.5 wt%) of hydrophilic colloids were added to the lotus root starch dispersion, and the mixture was continuously stirred to ensure uniform dispersion. The compound systems (LRS-XG, LRS-SA, LRS-GG, and LRS-GA) were placed in an 80℃ water bath and gelatinized for 40 min with stirring. After gelatinization, the samples were cooled to room temperature for rheological determination. The gelatinized samples were then placed in molds (30 mm in diameter and 30 mm in height) and re-gelatinized at 4℃ for 12 h for gel characterization. The gel samples were freeze-dried for microstructure observation. After the gelatinized samples were removed and naturally cooled to room temperature, they were placed in the printer cartridge and then recrystallized at 4℃ for 12 h to obtain the lotus root starch compound system 3D printing raw material.

[0082] Measurement method:

[0083] (1) Rheological properties

[0084] Experimental Methods: A rheometer (DHR-1, America) was used with a plate measurement system. A plate with a diameter of 40 mm and a gap of 1000 μm was selected. The rheological properties of different samples were studied at 25 °C. Following the steps in Example 1, the samples were gelatinized, cooled to room temperature, placed in the center of the plate, and excess sample at the edges was scraped off for steady-state rheological measurements. The apparent viscosity ranged from 0 to 300 s⁻¹. -1 Within the range. The scanning strain was set to 1%, and the scanning angular frequency range was 1-100 rad / s. This was used to measure the dynamic rheology of the compound system gel to obtain the storage modulus (G′), loss modulus (G″), and loss tangent (tanδ=G″ / G′) of the sample. Each sample was repeated three times.

[0085] (2) Gel properties

[0086] Experimental Method: The sample was gelatinized according to Example 1. After gelatinization, the sample was placed in a mold (30 mm in diameter, 30 mm in height), sealed with plastic wrap, and refrigerated at 4°C for 12 hours. The sample was then removed and placed at 25°C for 30 minutes. The gel properties were measured using a physical property analyzer (Vienna Court, Lamas Road, Godalming GU71YL, UK). The experimental conditions were as follows: probe P / 50, TPA mode measurement, test speed 1 mm / s, compression ratio 35%, trigger stress 5 g.

[0087] (3) Scanning electron microscopy analysis of gel samples

[0088] Experimental Methods: The gel sample from Example 1 was freeze-dried, and the microstructure characteristics of the freeze-dried sample at 100x magnification were observed using a microscope (JSM-7001F, JEOLLtd., Japan). An appropriate amount of freeze-dried sample was fixed on a conductive platform with conductive adhesive and sputtered with gold for 5 minutes, and then observed under an accelerating voltage of 15kV.

[0089] (4) 3D printing behavior analysis

[0090] The material cylinder was loaded into the printer, and a 18G printhead was used to perform 3D printing behavior analysis at a pressure of 35 PSI.

[0091] Results analysis:

[0092] Depend on Figure 2 It is known that the apparent viscosity of LRS and LRS-hydrocolloid gel decreases with increasing shear rate, exhibiting shear-thinning behavior, a typical characteristic of pseudoplastic fluids. This behavior allows gel inks to be easily extruded under high-shear printing conditions and can be layered, showing great potential in the field of 3D printing. This may be because lotus root starch and hydrocolloids are both macromolecular polysaccharides. Under shear force, highly polymerized molecules continuously decompose into short-chain molecules, thereby weakening the interaction between them and reducing viscosity. The apparent viscosity of lotus root starch mixed with XG, SA, and GG is higher than that of native starch. Conversely, the apparent viscosity of the GA mixed system decreases, almost dropping to zero with increasing shear rate. This phenomenon is unfavorable for the stacking of samples after 3D printing. This may be because GA is a spherical polymeric polysaccharide with a highly branched structure. The presence of ions affects the interaction between LRS and water molecules, inhibiting starch particle swelling, thus making it difficult for starch to gelatinize completely, leading to a decrease in viscosity.

[0093] Figure 3 (AD) shows the dynamic rheological results of samples G′ and G″ as a function of angular frequency. The results indicate that G′ and G″ of the mixture of native starch and four hydrocolloids increase with increasing angular frequency, exhibiting a frequency-dependent relationship. Furthermore, G′ is consistently greater than G″, suggesting that the system primarily exhibits elastic behavior. Additionally, the addition of XG, SA, and GG to the LRS increases the values ​​of G′ and G″ in a concentration-dependent manner, likely due to the formation of a denser network structure between starch-starch and starch-hydrocolloid molecules within the LRS-hydrocolloid matrix. At the same concentration, XG has the most significant effect on G′, reaching a maximum at a concentration of 1.5%. A sufficiently high G′ in the gel system can maintain the structural stability of the printed product.

[0094] To evaluate viscoelastic behavior, tanδ is defined as the ratio of G″ / G′. For example... Figure 4As shown in (AD), all LRS-based gels have tanδ values ​​less than 1, indicating that these gels exhibit elastic behavior rather than viscous, liquid-like behavior. The addition of XG leads to a significant decrease in tanδ, with a greater effect observed at higher concentrations. This phenomenon can be attributed to the rigid rod-like molecular conformation of XG, which enhances the binding force with starch, resulting in a denser network structure and higher elastic behavior. This increased elasticity also contributes to improved precision in 3D printed products.

[0095] Figure 5 The effects of XG, SA, GG, and GA on the structural properties of LRS gels were shown, with different types and concentrations of hydrocolloids resulting in varying textures among the samples. Hardness, referring to the force required for a gel to deform to a specific degree, is an indicator of gel mechanical strength. The addition of XG, SA, and GG increased gel hardness, with XG having a greater effect than SA and GG. This increase in hardness may be attributed to the rearrangement-promoting and stabilizing network structure resulting from the interactions between LRS and hydrocolloids in the LRS-hydrocolloid matrix. Other studies have reported that the increase in gel hardness is due to hydrogen bonds between starch and hydrocolloids, which enhances the gel structure. Conversely, the addition of GA weakens gel hardness, likely due to its disruption of hydrogen bonds between starch molecules. This damage may hinder amylose leaching and weaken amylose rearrangement, leading to a decrease in gel hardness in the composite system.

[0096] Elasticity is an indicator of the ability of starch gels to recover deformation within a given time period after extrusion. The results showed that the addition of hydrocolloids (except GA) improved the elasticity of the gel samples in a concentration-dependent manner. Furthermore, the elasticity of LRS-XG gels was significantly greater than that of other LRS-based gels, indicating that XG has a stronger ability to improve the elasticity of LRS gels compared to SA and GG. These results are consistent with dynamic rheological data. The textural properties of LRS gels were significantly affected by XG, SA, GG, and GA. Among them, XG had a relatively large impact on the hardness and elasticity of LRS gels, indicating that the addition of XG can form a denser structure. The results of this study indicate that XG is an effective enhancer of the elasticity of lotus root starch gels, and its excellent elastic properties and deformation recovery ability can greatly improve the quality of 3D printed products.

[0097] The microstructure of LRS gel and LRS-hydrocolloid gel magnified 100 times is as follows: Figure 6The microstructure of all samples exhibited a honeycomb pattern. Compared to LRS gel, the addition of XG, SA, GG, and GA promoted the formation of a three-dimensional network structure and improved the uniformity of the gel pores. The number of pores increased with increasing concentration, accompanied by an increase in edge thickness, which may be attributed to the distribution of water in the gel samples. The increased thickness of the pore outer walls may indicate stronger intergranular forces between starch granules. The results show that, compared to LRS, the compound system has a denser gel structure, inhibits water separation, and enhances the uniformity of the honeycomb structure. Moreover, with the addition of an equal amount of hydrophilic colloid, the three-dimensional network structure of the LRS-XG system is smoother and more regular, which can be attributed to the interaction between XG molecules and the amylose and amylopectin in starch, filling the gaps and forming a smooth, sheet-like structure.

[0098] Figure 7 The images show the 3D printing effects of lotus root starch hydrogels with different hydrophilic colloid blends. As can be seen from the images, when the hydrophilic colloid content is 0.5%, the LRS-XG blend system produces relatively smooth lines with no obvious breakage. The LRS-SA, LRS-GG, and LRS-GA blend systems all exhibit varying degrees of breakage in their printed lines, resulting in poor line continuity. When the hydrophilic colloid content is 1.0%, the LRS-XG blend system produces relatively smooth 3D printed lines and can achieve basic model stacking, but the middle part of the rings still collapses. The LRS-SA and LRS-GG blend systems produce poor printing results, failing to achieve layer-to-layer stacking, with significant collapse and poor line continuity. The LRS-GA blend system exhibits some line continuity, but the layer-to-layer stacking is poor, and collapse is more pronounced than in the LRS-XG system. When the amount of hydrophilic colloid added is 1.5%, the compound system can achieve 10mm stacking, and the stacking effect is relatively good. The printing effect of other systems is not ideal. Although the LRS-GA compound system can achieve layer-to-layer stacking, the collapse is more serious and the shape fidelity is low.

[0099] In summary, the addition of 1.5% xanthan gum maximizes the G′ of the compound system, forming a dense network structure and higher elastic behavior, resulting in high shape retention in 3D printing and demonstrating its potential as a wall material for 3D printed functional pet food.

[0100] Example 1:

[0101] The effect of adding whole egg powder on the 3D printing behavior of the compound system was investigated according to the following steps:

[0102] (1) The optimal ratio of the compound system was obtained by using the 3D printing behavior analysis in Example 1.

[0103] (2) Lotus root starch was dispersed in distilled water at a concentration of 15 wt%.

[0104] (3) Add 1.5wt% XG to the lotus root starch dispersion and stir until evenly mixed.

[0105] (4) Add different concentrations of whole egg powder to the compound solution and stir to mix well, with no whole egg powder added as the control.

[0106] (5) Place the compound system from step (4) into an 80°C water bath and gelatinize it while stirring for 40 minutes.

[0107] (6) Take out the gelatinized compound system from step (5), let it cool naturally to room temperature, put it into the printer barrel, and then transfer it to a 4°C refrigerator for recrystallization for 12 hours to obtain lotus root starch 3D printing raw material.

[0108] (7) After the raw material in step (6) has been brought to room temperature, load the material into the printer.

[0109] (8) Install the 18G printhead into the cartridge.

[0110] (9) Use the controller to select the print model and print size.

[0111] (10) The pressure was adjusted to 35 PSI for 3D printing behavior analysis.

[0112] Measurement method:

[0113] (1) Morphological analysis of 3D printed samples

[0114] The material cylinder was loaded into the printer, and a 18G printhead was used to perform 3D printing behavior analysis at a pressure of 35 PSI.

[0115] (2) Colorimetric analysis

[0116] The colorimetry of the samples was determined using a CR-310 colorimeter. Before measurement, calibration was performed using a white plate, and the L of the sample was measured with reference to the original starch. * (brightness), a * (Redness) and b * (Yellowness). The color difference (ΔE) is calculated using the following formula (2):

[0117]

[0118] (3) Rheological properties

[0119] The printing material cooled to room temperature in Example 1 (6) was subjected to steady-state rheology and dynamic rheology measurements according to the method for determining rheological properties in Experiment 2 (1).

[0120] (4) Electronic nose analysis

[0121] The sensor materials corresponding to each detector of the electronic nose are shown in Table 2. Place 5g of sample in a dedicated electronic nose test bottle (50ml), seal, and equilibrate at room temperature for 1 hour before starting the test. Insert the probe and wait for the instrument to draw in air to detect volatile substances. Clean the electronic nose sensors for 50 minutes or more before the experiment, until the response values ​​of each sensor are close to 1. Parameter settings: air flow rate 1L / min, test time 100s, cleaning time 120s. Repeat the test 3 times for each sample.

[0122] Results analysis:

[0123] Figure 8 This image shows the 3D printing effects under different amounts of whole egg powder. The model is a ring with dimensions of 30mm diameter, 30mm height, and 4.2mm thickness. The images show that all shapes can be stacked to a height of 30mm, but the surface roughness and height deviation of each sample are significant. The printed sample without whole egg powder shows a large difference between the upper and lower diameters, resulting in significant shape changes. When the whole egg powder content is 0.5%, the overall shape of the ring is preserved, and the upper and lower diameters are basically matched, but the lines are not smooth enough, and the printing deviation is large. When the whole egg powder content is 1%, the ink output is relatively uniform, the lines are relatively smooth, the ring shape retention is the highest, and the overall effect is good. However, as the whole egg powder content increases, the shape retention of the printed product gradually decreases, and the height and thickness deviations are larger. The height, diameter, and thickness of different printed samples were measured using calipers and compared with the model dimensions. The results are as follows. Figure 9 As shown in the figure, when the amount of whole egg powder added is 1%, the size of the printed product is closest to the size of the model, while the printed product without whole egg powder has the largest deviation in height and thickness.

[0124] Figure 10 The changes in colorimetric parameters of native starch, gelatinized starch, and printed samples are shown, with significant changes observed after gelatinization and printing. From... Figure 10 It can be seen that the formation of starch gel after gelatinization and printing significantly reduces the L of starch. * This is due to the starch granules absorbing water, swelling, and rupturing during gelatinization, and the release of water from the cold gel during recrystallization / rebound. The expansion, rupture, and gelatinization of starch granules during gelatinization increases the transparency of the starch gel compared to the original starch powder, which also leads to a higher glycemic index (b). *The value changes. Compared to native starch, the ΔE value of starch increases significantly during gelatinization. However, the change in ΔE during printing (or extrusion) is smaller compared to gelatinization, indicating that 3D printing has little impact on the color change of starch samples. The ΔE value of gel samples with added whole egg powder is smaller than that without added whole egg powder, and gradually decreases with increasing concentration. Due to the color of whole egg powder itself, the b of the compound system... * The value increased, but the increase was not significant. Although the addition of whole egg powder had some impact on the color difference of the sample, the impact was not very obvious and would not affect consumer acceptance.

[0125] Table 2. Sensing materials corresponding to each detector of the electronic nose

[0126]

[0127] Figure 11 The rheological properties of printing inks with different amounts of whole egg powder added are shown. Extrusion printing requires materials that are pseudoplastic fluids with shear-thinning behavior. The gel sample exhibits low viscosity and strong shear-thinning behavior under shear stress, making it easy to extrude. Figure 11 A steady-state shear flow curve clearly shows the change in apparent viscosity for all samples. The apparent viscosity of all gels decreases with increasing shear rate (shear thinning behavior), resulting in viscoelastic gels. This also indicates that the gels exhibit pseudoplastic behavior, making them easily extruded from the printer nozzle under appropriate shear force and capable of rapid structural recovery and curing after extrusion. Figure 11 B shows the dynamic rheological properties of the gel sample, reflecting the fluid's flow properties and deformation capacity under periodic motion conditions. G′ represents the deformation energy stored in the gel during elastic deformation, reflecting the sample's elasticity. G″ refers to the energy loss caused by viscous deformation (irreversible), reflecting the sample's viscosity. Due to the viscoelasticity of starch gels, in the linear viscoelastic region ( Figure 11 B), G′ is higher than G″, indicating the potential to form an elastic gel or gel-like structure. The addition of whole egg powder increases both G′ and G″ in the compound system, showing a concentration-dependent effect; the higher G′, the better the shape retention of the material. However, with further increases in G′, extrusion performance deteriorates, the extruded filament breaks easily, and the resolution is low, with a large deviation from the target structure and numerous defects. Adding 1% whole egg powder places G′ at the middle level across all samples, suggesting better shape retention, a result consistent with 3D printing precision analysis. Tanδ is defined by G″ / G′. A tanδ value less than 1 indicates predominantly elastic behavior, while a value greater than 1 indicates predominantly viscous behavior. Higher tanδ values ​​indicate more fluid-like behavior, while lower tanδ values ​​indicate less fluidity and behavior closer to a solid. From Figure 11 As can be seen from C, the tanδ values ​​of all samples are less than 1, indicating elastic behavior. Adding 1% whole egg powder results in stronger gel elasticity, better gelation effect, and is more conducive to maintaining the printed shape.

[0128] Electronic noses utilize electrochemical sensing systems to analyze, identify, and detect odors and volatile substances. Multiple sensors sensitive to different odors detect volatile substances and convert them into data signals, thus enabling the analysis of the odor of the sample. Therefore, the analysis results of the electronic nose provide a comprehensive description of the sample's odor. Radar graphs were plotted on the data from various sensors of the electronic nose for gel samples with different amounts of whole egg powder added, and the results are compared as follows. Figure 12 As shown, different sensors exhibit varying signal intensities in response to different samples. The gel with added whole egg powder showed higher response values ​​on the W2S, W1W, and W1S sensors, representing alcohols, aldehydes, ketones, some aromatic compounds, and sulfur-containing compounds, respectively. Alcohols have a low olfactory threshold and mainly originate from lipid oxidation and degradation; aldehydes often present barbecue, meat, and fatty aromas, generally formed through the further reaction of hydroperoxides generated by lipid oxidation; ketones are typical flavor compounds in the Maillard reaction, usually formed by lipid peroxidation of carbonyl and amino compounds, Maillard reactions, or further oxidation and decomposition of some alcohols and esters, significantly influencing the formation of characteristic flavor compounds in food. Studies have shown that common flavor compounds in pet palatability enhancers are mainly those presented by the W2S sensor. Figure 12 It can be seen that when whole egg powder is added, the response value of W2S increases significantly, meaning that the odor detected by the sensor is stronger. This indicates that the addition of whole egg powder can change the flavor of printed products, not only improving the nutritional value of the products but also stimulating their appetite for pets.

[0129] In summary, when the addition of whole egg powder is 1%, the G′ of the gel sample is appropriately increased, resulting in better shape retention. The addition of whole egg powder has a certain impact on the color difference of the sample, but it does not affect consumer acceptance. The W2S response value increases significantly after the addition of whole egg powder. When the addition of whole egg powder is 1%, the size of the printed product is closest to the model size, exhibiting high shape retention, making it suitable as a wall material for functional pet treats.

[0130] Example 2:

[0131] The preparation of functional pet treats shall be carried out according to the following steps:

[0132] (1) The optimal ratio of the compound system was obtained according to Example 1.

[0133] (2) Lotus root starch was dispersed in distilled water at a concentration of 15 wt%.

[0134] (3) Add 1.5wt% XG and 1.0wt% WEP to the lotus root starch dispersion and stir until homogeneous.

[0135] (4) Add shark chondroitin solutions of different concentrations (0.5wt%, 1.0wt%, 1.5wt%, 2.0wt%) to the dispersion and stir until homogeneous.

[0136] (5) Place the compound system from step (4) into an 80°C water bath and gelatinize it while stirring for 40 minutes.

[0137] (6) Take out the gelatinized compound system from step (5), let it cool naturally to room temperature, put it into the printer barrel, and then transfer it to a 4°C refrigerator for recrystallization for 12 hours to obtain functional pet snack 3D printing raw material.

[0138] (7) After the raw material in step (6) has been brought to room temperature, load the material into the printer.

[0139] (8) Install the 18G printhead into the cartridge.

[0140] (9) Use the controller to select the print model and print size.

[0141] (10) The pressure was adjusted to 35 PSI for 3D printing behavior analysis.

[0142] Measurement method:

[0143] (1) Standard curve of shark chondroitin

[0144] Reagents:

[0145] Borax-sulfuric acid solution: Weigh 4.77g of sodium tetraborate and dissolve it in 500ml of concentrated sulfuric acid (AR). (A proportional diluent can be used.) Carbazole test solution: Weigh 0.125g of carbazole and dissolve it in 100ml of ethanol (AR) (prepare fresh before use).

[0146] Standard curve plotting:

[0147] Accurately weigh 25 mg of shark chondroitin sulfate standard and dilute to volume in a 100 ml volumetric flask. Use this as the stock solution to prepare reference solutions with concentrations of 0.05, 0.10, 0.15, 0.20, and 0.25 mg / ml. Take six graduated test tubes with stoppers and add 5 ml of borax-sulfuric acid solution to each. Cool in an ice-water bath, then add 1 ml of blank solution (distilled water) and 1 ml of each of the reference solutions of different concentrations. Gently shake, then mix thoroughly, continuously cooling in an ice-water bath. Heat the test tubes in boiling water for 10 min and cool. Add 0.2 ml of carbazole reagent, mix well, heat in a water bath for 15 min, and cool. Measure the absorbance A at 530 nm and plot the absorbance against concentration C to create a standard curve.

[0148] (2) Relationship between shark chondroitin dissolution order and loading rate

[0149] According to Example 2, the loading rates of shark chondroitin dissolved sequentially in the compound system were compared. ChS was first dissolved in lotus root starch, followed by the sequential addition of XG and EP, gelatinizing to form a gel ink. 2g of the gel sample was dissolved in distilled water, thoroughly stirred and shaken, then centrifuged. The ChS content (C1) in the supernatant was measured, and the loading rate was calculated as (1-C1 / addition amount) x 100%. After adding LRS, XG, and EP, ChS was added again to gelatinize and form a gel, and the ChS loading rate was tested using the same method.

[0150] (3) The effect of different amounts of shark chondroitin on gel 3D printing behavior

[0151] The material cylinder was loaded into the printer, and a 18G printhead was used to perform 3D printing behavior analysis at a pressure of 35 PSI.

[0152] Results analysis:

[0153] Figure 15 The results showed that the ChS content in the gel samples after dissolving shark chondroitin first reached 85.65%, while the loading rate of the gel samples after dissolving shark chondroitin second was significantly lower at 79.75%. In conclusion, the optimal process sequence for functional pet food is to first dissolve shark chondroitin, then add LRS, XG, and EP sequentially, and stir until homogeneous and gelatinized to obtain the gel ink.

[0154] Following the steps in Example 2, different concentrations of shark chondroitin were first dissolved in lotus root starch dispersion. Then, XG and WEP were added sequentially to prepare gel ink, and the printing effect was verified. The printing results are as follows. Figure 16As shown in the figure, when the concentration of shark chondroitin is below 2%, the printing precision of the bone model is high, and the model's inherent shape is maintained. When the shark chondroitin concentration reaches 2%, more ink is extruded, the printing precision decreases, and the printed lines become rougher. Various degrees of ink buildup appear on the surface (circled in the figure), and shape retention decreases.

[0155] In summary, in order to maximize the loading of shark chondroitin, this invention uses 1.5% shark chondroitin for loading to prepare functional pet snacks.

[0156] Example 3:

[0157] The impact of different post-processing methods on the quality of functional pet treats was investigated using the following steps:

[0158] (1) 15 wt% of lotus root starch was dispersed in distilled water.

[0159] (2) Dissolve 1.5 wt% shark chondroitin in lotus root starch solution.

[0160] (3) Add 1.5wt% XG and 1.0wt% WEP to the lotus root starch dispersion and stir until homogeneous.

[0161] (4) Place the compound system from step (3) into an 80°C water bath and gelatinize it while stirring for 40 minutes.

[0162] (5) Take out the gelatinized compound system from step (4), let it cool naturally to room temperature, put it into the printer barrel, and then transfer it to a 4°C refrigerator for recrystallization for 12 hours to obtain functional pet snack 3D printing raw material.

[0163] (6) After the raw material in step (5) has been brought to room temperature, load the material into the printer.

[0164] (7) Install the 18G printhead into the cartridge.

[0165] (8) Use the controller to select the print model and print size.

[0166] (9) The pressure intensity was adjusted to 35 PSI for 3D printing behavior analysis.

[0167] (10) Dry the 3D printed sample: air drying, freeze drying, hot air drying, microwave drying.

[0168] (11) Compare the effects of different drying methods on the quality of functional pet snacks.

[0169] Measurement method:

[0170] The 3D printed samples were dried using different drying methods. The brittleness of the dried products was analyzed and determined using a physical property analyzer. The test conditions were as follows: a 4mm cylindrical probe was used for the puncture test, the Return-to-start mode was selected, the speed before and after the test was 3mm / s, the test speed was 0.5mm / s, the trigger force was 10g, and the return distance was 15mm.

[0171] Results analysis:

[0172] Figure 17 The images show the results of pet treat products obtained after different post-drying methods. Figure 18 The results show the brittleness analysis of samples after different post-treatments. The results revealed that samples air-dried at room temperature exhibited severe deformation, with significant shape loss and the highest brittleness value, indicating maximum hardness. Freeze-dried samples maintained their shape well, completely preserving the printed sample without any deformation, demonstrating strong shape retention. Their brittleness value remained within a low range, indicating good palatability. Hot-air drying resulted in varying degrees of bending, with the bone model largely destroyed. Shape retention was low, and the brittleness value was high, indicating significant hardness. Microwave drying caused the most severe deformation, with localized high temperatures leading to fracture and deformation. Uneven drying between the top and bottom of the sample resulted in the most severe damage, with a low brittleness value, likely due to uneven heating causing significant structural damage. In conclusion, freeze-drying offers the highest shape retention and the best product quality.

[0173] Example 4:

[0174] The study on the anti-inflammatory effects of functional pet treats was conducted according to the following steps:

[0175] (1) 15 wt% of lotus root starch was dispersed in distilled water.

[0176] (2) Dissolve 1.5 wt% shark chondroitin in lotus root starch solution.

[0177] (3) Add 1.5wt% XG and 1.0wt% WEP to the lotus root starch dispersion and stir until homogeneous.

[0178] (4) Place the compound system from step (3) into an 80°C water bath and gelatinize it while stirring for 40 minutes.

[0179] (5) Take out the gelatinized compound system from step (4), let it cool naturally to room temperature, put it into the printer barrel, and then transfer it to a 4°C refrigerator for recrystallization for 12 hours to obtain functional pet snack 3D printing raw material.

[0180] (6) After the raw material in step (5) has been brought to room temperature, load the material into the printer.

[0181] (7) Install the 18G printhead into the cartridge.

[0182] (8) Use the controller to select the print model and print size.

[0183] (9) The pressure intensity was adjusted to 35 PSI for 3D printing behavior analysis.

[0184] (10) Freeze-dry the 3D printed sample.

[0185] (11) The freeze-dried sample was administered to arthritic mice by gavage with different doses of shark chondroitin to verify its anti-inflammatory efficacy. Assay method:

[0186] (1) Establishment of an arthritis mouse model (OA)

[0187] Forty 10-week-old male mice were acclimatized for one week and then randomly divided into a normal control group (n=10) and a model group (n=30, further divided into an OA model group, a low-dose group, and a high-dose group, with 10 mice in each group). Each of the four groups was fed a basal diet. On days 0, 2, 4, and 6 of the experiment, an arthritis model was established by injecting 5 U (4 μL) of type II collagenase solution into the right knee joint space. The normal control group received 4 μL of sterile saline as a control.

[0188] (2) Administration

[0189] After arthritis modeling, all groups were administered the medication daily via gavage at a volume of 0.1 mL / 10 g. Freeze-dried functional pet treats were pulverized and administered via gavage at a fixed dose of 300 mg / kg daily, based on shark chondroitin content. The low-dose group received 100 mg / kg daily. The negative control and model groups received an equal volume of physiological saline via gavage daily. Gavage was continued for 4 weeks, and joint swelling was observed daily.

[0190] (3) Joint swelling

[0191] Four weeks after drug intervention, animals were sacrificed and serum was collected. Mice were then dissected, joints were harvested, muscles were removed, and the transverse diameter of the left and right joints was measured using calipers. The degree of joint swelling (%) was calculated. The formula is:

[0192] Swelling (%) = (Diameter of right knee joint - Diameter of left knee joint) / Diameter of left knee joint × 100%.

[0193] (4) Enzyme-linked immunosorbent assay

[0194] Blood was collected from mouse eyeballs and placed obliquely on ice for 3 hours, then centrifuged at 3000 rpm for 10 minutes to separate serum. IL-1β and IL-4 enzyme-linked immunosorbent assay (ELISA) kits were used, and their expression levels in serum were detected according to the manufacturer's instructions. Each group was tested three times, and the average expression level for each group was calculated based on the standard curve.

[0195] Results analysis:

[0196] (1) Joint swelling analysis

[0197] Figure 19 The study shows the joint swelling in mice in different groups after 4 weeks of administration of functional pet treats. As can be seen from the figures, the OA group showed the most significant swelling, with the diameter of the right leg joint being much larger than that of the left leg. The low-dose group also showed significant swelling, but less than the OA group. The high-dose group showed significantly less swelling than the OA and low-dose groups, but was still relatively more swollen than the negative control group. Figure 20 The final experimental results showed that the OA group had the highest joint swelling, and the high-dose group had less joint swelling than the low-dose group. This indicates that the low-dose (100mg / kg) intervention has a certain degree of inhibitory effect on knee joint swelling. Compared with the low dose, the high-dose (mg / kg) intervention has a more obvious inhibitory effect on joint swelling.

[0198] (2) Serum IL-1β and IL-4 expression level analysis

[0199] The expression levels of IL-1β and IL-4 in the serum of each group of animals were analyzed by ELISA. The results are as follows: Figure 21 As shown in Figures AB, the serum IL-1β expression level in the model group mice was significantly higher than that in the negative control group after modeling, reaching 104.34 pg / ml. Conversely, the serum IL-4 expression level in the model group was significantly lower than that in the negative control group, reaching 26.52 pg / ml. Compared with the model group, the serum expression levels of both cytokines in the low-dose group showed some improvement, but the effect was not as significant as that in the high-dose group. The serum IL-1β level in the high-dose group was significantly lower than that in the model group, reaching 22.09 pg / ml; the serum IL-4 level was significantly higher than that in the model group, reaching 52.27 pg / ml. In conclusion, the functional pet snack prepared in this invention can significantly improve the inflammatory state of OA, indicating that the functional pet snack prepared in this invention has good anti-inflammatory effects.

Claims

1. A functional pet snack, characterized in that... It is prepared from the following raw materials in parts by weight: 1-20 parts lotus root starch Xanthan gum 0.5-2 parts, 0.5-2 parts whole egg powder, Shark chondroitin 0.5-2 parts, Make up the total to 100 portions with purified water; Prepare according to the following steps: (1) Lotus root starch was dispersed in purified water at a concentration of 15 wt%. (2) Slowly add shark chondroitin to the starch solution and stir thoroughly to dissolve it completely; (3) Add xanthan gum and whole egg powder to step (2) in sequence and stir thoroughly to make them evenly mixed; (4) Place the mixed solution from step (3) into a water bath to gelatinize; (5) Take out the gelatinized composite solution starch paste from step (4), let it cool naturally to room temperature, put it into the printer barrel, and then transfer it to a 4°C refrigerator for recrystallization to obtain functional pet snack raw materials. (6) After the pet treat ingredients in the canister from step (5) have been brought to room temperature, use a 3D printer to perform 3D printing; (7) Dry the printed product obtained in step (6); The concentration of shark chondroitin in step (2) is 1.5 wt%. The concentration of whole egg powder mentioned in step (3) is 1 wt%; the concentration of xanthan gum is 1.5 wt%; The gelatinization conditions in step (4) are 80°C for 40 min; The recrystallization time in step (5) is 8-12 h. The 3D printer parameters mentioned in step (6) are: pressure 35 PSI, syringe size 18 G, and printing speed 30 mm / s; The drying methods described in step (7) are: natural air drying and freeze drying.

2. The functional pet snack according to claim 1, characterized in that... It is prepared from the following raw materials in parts by weight: 15 parts lotus root starch 1.5 parts xanthan gum 1 portion of whole egg powder 1.5 parts shark chondroitin Make up to 100 servings with purified water.

3. A functional pet snack according to claim 1, characterized in that... The recrystallization time in step (5) is 12 h.

4. A functional pet snack according to claim 1, characterized in that... The drying method described in step (7) is freeze drying.

Images