Pet food compositions and methods for improving fecal quality

Abstract

A hydrolyzed keratin-containing material, a method for preparing such a material, and a composition comprising such a material are described. The method may include combining a keratin-containing material with an acid, subjecting the keratin-containing material to steam hydrolysis, and reducing the particle size of the keratin-containing material. The hydrolyzed keratin-containing material may contain up to 1.0% by weight of lanthionine, based on the total weight of the hydrolyzed keratin-containing material.

Description

Description of Related Applications

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 313,428, filed February 24, 2022, the contents of which are incorporated herein by reference in their entirety. [Technical field]

[0002] The present disclosure relates generally to pet food compositions and methods, including compositions having reduced lanthionine content, useful for improving feces quality. [Background technology]

[0003] As the demand for alternative protein sources for use in pet food and other animal feeds increases, protein-containing materials such as animal-derived ingredients are becoming increasingly useful. For example, feathers from poultry and other materials such as wool, hair, fur, nails, claws, and bristles usually contain abundant amounts of keratin protein. However, such materials often have low digestibility. Processing of keratin materials to improve digestibility can produce compounds with undesirable gastrointestinal effects. Summary of the Invention

[0004] The present disclosure includes hydrolyzed keratin-containing materials, methods for preparing hydrolyzed keratin-containing materials, and compositions containing such materials.

[0005] In certain embodiments, a method for preparing a hydrolyzed keratin-containing material includes combining a keratin-containing material with an acid, subjecting the keratin-containing material to steam hydrolysis, and reducing the particle size of the keratin-containing material to a particle size of 100 μm or less. 50In certain embodiments, the keratin-containing material can be combined with an acid prior to and / or during treatment with steam hydrolysis to achieve a pH ranging from about 2 to about 5. In various embodiments, the particle size reduction step can occur prior to combining with the acid, prior to treating with steam hydrolysis, and / or after treating with steam hydrolysis. In some aspects of the present disclosure, the treating with steam hydrolysis can occur at a pressure of about 0 to about 100 psig (about 0 to 790801 Pa). In certain embodiments, the keratin-containing material can include feathers, hair, wool, beaks, hides, bristles, horns, hooves, pincers, claws, scales, or mixtures thereof. Additionally, in certain aspects of the present disclosure, the hydrolyzed keratin-containing material can include 1.0% or less by weight lanthionine based on the total weight of the hydrolyzed keratin-containing material. The hydrolyzed keratin-containing material can optionally include 0.5% or less by weight lanthionine.

[0006] The present disclosure also includes hydrolyzed keratin-containing materials prepared according to the methods described herein above and elsewhere. In certain embodiments, the hydrolyzed keratin-containing materials may have a lanthionine content of 1.0% or less, 0.5% or less, or 0.25% or less by weight, based on the total weight of the hydrolyzed keratin-containing material ...d particle size ranging from about 1 μm to about 30 μm. 10 particle size, and / or d ranging from about 80 μm to about 160 μm 90 particle size, and / or d ranging from about 30 μm to about 70 μm 50 In particular embodiments, the hydrolyzed keratin-containing material may have a Boisen digestibility of greater than about 70%, or from about 70% to about 90%.

[0007] Also disclosed herein are compositions comprising hydrolyzed keratin-containing materials as described above and elsewhere herein. According to some aspects of the present disclosure, the compositions may be pet food compositions. In certain embodiments, the compositions may comprise up to about 20% by weight, such as about 1% to about 20% by weight, of hydrolyzed keratin-containing materials. In particular embodiments, the compositions may comprise up to 0.2% by weight of lanthionine, such as about 0.01% to 0.2% by weight of lanthionine, based on the total weight of the composition. In some aspects of the present disclosure, the hydrolyzed keratin-containing materials may be, comprise, or consist of hydrolyzed feather meal. In certain embodiments, the compositions may further comprise at least one protein source other than the hydrolyzed keratin-containing materials. In certain embodiments, the at least one protein source other than the hydrolyzed keratin-containing material may include an animal protein, such as chicken, turkey, beef, pork, lamb, venison, duck, or salmon; and / or a vegetable protein, such as corn gluten flour or wheat gluten. In certain embodiments, the composition may further include at least one carbohydrate, such as corn, rice, wheat, sorghum, or barley, and / or at least one lipid, such as poultry fat, beef tallow, or vegetable oil.

[0008] The present disclosure also includes a method of improving fecal quality in an animal. In certain embodiments, the method may include administering to the animal a composition as described hereinabove and elsewhere. In particular embodiments, the composition may be a dry pet food. In particular embodiments, the animal may be a dog or a cat. In particular embodiments, the animal's fecal quality value may be from about 2 to about 4. The present disclosure further includes the use of a composition as described hereinabove and elsewhere for improving the fecal quality of an animal. Optionally, the animal may be a dog or a cat. In particular embodiments, the animal's fecal quality value may be from about 2 to about 4.

[0009] The present disclosure also includes hydrolyzed keratin-containing materials. In certain embodiments, the hydrolyzed keratin-containing materials may contain 1.0% or less by weight of lanthionine, such as 0.5% or less by weight of lanthionine, based on the total weight of the hydrolyzed keratin-containing material. The hydrolyzed keratin-containing materials may contain keratin having a diameter ranging from about 1 μm to about 30 μm. 10 Particle size, ranging from about 80 μm to about 160 μm 90 particle size, and / or d ranging from about 30 μm to about 70 μm 50 In particular embodiments, the hydrolyzed keratin-containing material comprises hydrolyzed feather meal.

[0010] The present disclosure also includes a composition comprising up to about 20% by weight, e.g., from about 1% to about 20% by weight, of a hydrolyzed keratin-containing material. The composition may also comprise at least 5% by weight of a protein source other than the hydrolyzed keratin-containing material. The composition may be a pet food composition. The composition may comprise 0.2% or less, 0.15% or less, or 0.1% or less by weight of lanthionine, based on the total weight of the composition.

[0011] Additional features and advantages of the present application will be described hereinafter which form the scope of the claims of this application. Those skilled in the art will recognize that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present application. Those skilled in the art will also recognize that such equivalent constructions do not depart from the nature and scope of the present application as set forth in the appended claims. The novel features believed to be characteristic of the present application, both as to its organization and method of operation, together with further objects and advantages, will be more readily understood from the following description. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Aspects of the present disclosure include methods for preparing keratin protein-containing materials useful in pet foods, and pet food compositions containing such materials, which methods and compositions herein can enhance digestibility while maintaining acceptable fecal quality.

[0013] definition The terms used herein generally have their ordinary art meanings, within the context of this disclosure, and in the specific context in which each term is used. Certain terms are set forth below or elsewhere in the specification to provide additional guidance in describing the compositions and methods of the disclosure, and how to make and use them.

[0014] As used in this specification and the appended claims, nouns include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a "compound" includes a mixture of compounds.

[0015] As used herein, the terms "comprises," "comprising," "includes," "including," or any other variation thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements does not include only those elements, but may include other elements that are not expressly recited or that are inherent to such process, method, article, or apparatus.

[0016] The terms "about" and "approximately" mean within an acceptable error range of a particular value as determined by one of ordinary skill in the art, which will depend in part on how the value is measured or determined, i.e., the limitations of the measurement system. For example, "about" can mean within or more than three standard deviations, in accordance with practice in the art. Alternatively, "about" can mean within a range of up to 20%, preferably up to 10%, more preferably up to 5%, and even more preferably up to 1% of a given value. Alternatively, particularly with respect to a system or process, the term can mean within an order of magnitude, preferably within 5-fold, and more preferably within 2-fold, of a value.

[0017] In the detailed description herein, references to "an embodiment," "an embodiment," "one embodiment," "various embodiments," and the like indicate that the described embodiment may include a particular feature, structure, or characteristic, but all embodiments may not necessarily include that particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in connection with one embodiment, it is believed to be within the knowledge of one of ordinary skill in the art to affect such feature, structure, or characteristic in connection with other embodiments, whether or not expressly described. After reading this description, it will be apparent to one of ordinary skill in the art how to implement the present disclosure in alternative embodiments.

[0018] method The low digestibility of keratin-containing materials is understood to be related to the structural integrity of cysteine ​​disulfide bonds. Processing of keratin-containing materials by conventional methods can result in the formation of compounds that have undesirable gastrointestinal effects.

[0019] Lanthionine is an amino acid formed from cysteine:

[0020] [ka]

[0021] Lanthionine is present in small amounts in keratin-containing materials, but harsh processing conditions, such as high heat, high pressure, and / or the use of alkaline reagents, can significantly increase the lanthionine content of the material. The methods disclosed herein, including hydrolysis and size reduction under acidic pH conditions, have been found to increase the digestibility of keratin-containing materials by producing relatively low amounts of lanthionine. The relatively low amounts of lanthionine can provide a pet food composition that avoids undesirable gastrointestinal effects such as diarrhea and loose stools. Thus, the compositions and methods herein can improve the fecal quality of animals, including pet / companion animals such as cats and dogs.

[0022] In certain embodiments of the present disclosure, keratin-containing materials suitable for the methods herein include animal-derived components such as, but not limited to, feathers, hair, wool, hides, bristles, horns, beaks, hooves, pincers, claws, scales, and mixtures thereof. Keratin-containing materials can be unprocessed or raw, meaning that the material is obtained from a natural source, for example, from a living animal that sheds the material, or as a by-product removed before and / or during meat processing.

[0023] If desired, the raw / unprocessed keratin-containing material may undergo one or more pretreatment steps to remove extraneous components such as blood, offal, residual tissue, and / or foreign bodies (e.g., wood, plastic, metal, stone, etc.). The pretreatment steps may include cleaning the raw / unprocessed keratin-containing material, such as washing with ambient or warm water. If desired, a suitable surfactant may be used in the ambient or warm water during washing.

[0024] The treatment of keratin-containing materials herein may include, for example, thermal hydrolysis at acidic pH for protein hydrolysis. In certain embodiments, thermal hydrolysis may utilize steam under mild processing conditions. In certain embodiments, keratin-containing materials may be subjected to steam hydrolysis at atmospheric pressure (0 psig=101325 Pa) or under pressure, for example, at pressures of 0 psig (101325 Pa) to about 100 psig (790801 Pa), for example, at pressures of about 10 psig (170249 Pa) to about 50 psig (446047 Pa), or about 25 psig (273673 Pa) to about 75 psig (618421 Pa). Steam hydrolysis can be carried out for at least 1 minute, for example, from about 1 minute to 60 minutes or longer, or from about 1 minute to about 60 minutes, from about 15 minutes to about 60 minutes, from about 1 minute to about 10 minutes, or from about 3 minutes to about 15 minutes. In some embodiments of the present disclosure, the keratin protein-containing material can be subjected to steam hydrolysis for about 1 minute, about 5 minutes, about 10 minutes, about 15 minutes, about 20 minutes, about 25 minutes, about 30 minutes, or about 35 minutes at a pressure of about 0 psig (101325 Pa) to about 100 psig (790801 Pa). Various forms of agitation (e.g., shaking or stirring) can be applied as needed during steam hydrolysis, for example to facilitate uniform application of heat throughout the material.

[0025] The pH of the keratin-containing material can be maintained at an acidic pH before and / or during steam hydrolysis. In certain embodiments, an acid or acid solution can be added to the material and / or combined with the steam to provide a pH of 5 or less. In certain embodiments, the pH of the keratin-containing material can range from about 2 to about 5, alternatively from about 3 to about 5, from about 4 to about 5, from about 2.5 to about 4.5, or from about 2 to about 3.5. In certain embodiments, examples of acids that can be used to lower the pH to a desired range include, but are not limited to, hydrochloric acid (e.g., hydrochloric acid solution), phosphoric acid (e.g., phosphoric acid solution), sulfuric acid (e.g., sulfuric acid solution), and organic acids such as citric acid, acetic acid, malic acid, lactic acid, propionic acid, and tartaric acid, among other suitable acids.

[0026] In certain embodiments, the acid can be mixed with water and heated with steam to achieve a pH of about 2 to about 5, and then the keratinous material can be added and subjected to steam hydrolysis. Additionally or alternatively, steam can be continuously introduced into the acid solution and applied to the keratinous material to provide a pH of about 5 or less. The pH can be adjusted as needed (e.g., by addition of acid, or, if the pH is too low, by addition of base) to maintain the desired pH over the course of hydrolysis.

[0027] The methods disclosed herein may include one or more size reduction steps to provide particulate keratin-containing material with a desired particle size distribution. In certain embodiments, size reduction techniques include, but are not limited to, grinding (e.g., using a grinder for coarse and / or fine grinding) and milling (e.g., using a ball mill). One or more size reduction steps may be performed before, during, or after any other step of the methods herein. In certain embodiments, size reduction may be performed before and / or after steam hydrolysis and / or before and / or after a step of lowering the pH of the keratin-containing material. In certain embodiments, raw / unprocessed keratin-containing material (e.g., feather material) may be subjected to coarse grinding followed by hydrolysis. Additionally, in certain embodiments, raw / unprocessed keratin-containing material (e.g., feather material) may undergo hydrolysis and the resulting hydrolyzed keratin-containing material may be subjected to fine grinding. In another embodiment, raw / unprocessed keratin-containing material (e.g. feather material) can be subjected to coarse grinding, followed by hydrolysis, and then fine grinding of the hydrolyzed keratin-containing material. Without being bound by theory, it is believed that the particle size reduction of the keratin-containing material combined with steam hydrolysis at acidic pH can promote cleavage of cysteine ​​disulfide bonds while minimizing lanthionine formation, thereby increasing digestibility.

[0028] Size reduction can be completed in one or multiple steps, e.g., two, three, four, or more size reduction steps, to achieve the desired particle size. Each size reduction step can be performed before, during, or after another treatment step (e.g., pretreatment, steam hydrolysis, and / or pH reduction), or two or more size reduction steps can be performed one after the other before, after, or during another treatment step. One or more size reduction steps can provide a particle size distribution in which at least about 90% by weight of the keratin-containing material has an average particle size of less than 160 μm. The average particle size (d 50 ) is the area where 50% of the particles are 50 The term d refers to a value that has a diameter smaller than the value (50% by weight of the particles are retained on a sieve having openings of a given size and larger). Similarly, d 90 The particle size is such that at least 90% by mass of the particles have that d 90 d refers to the value at which 10% by weight of the particles are retained on a sieve having openings of a given size and larger, and d 10 The particle size is such that at least 10% by mass of the particles have that d 10 The particle size refers to a particle size smaller than the size at which 90% by weight of the particles are retained on a sieve having openings of a given size or larger. Particle size can be measured by laser diffraction analysis or optical image particle size analysis.

[0029] In certain non-limiting embodiments, the keratin-containing material is 10 Particle size ranges from about 1 μm to about 30 μm, d 50 Particle size ranging from about 30 μm to about 70 μm, and / or d 90 In certain embodiments, the keratin-containing material has a particle size distribution ranging from about 80 μm to about 250 μm. 10 Particle size ranges from about 10 μm to about 25 μm, d 50 Particle size ranging from about 45 μm to about 60 μm, and / or d 90 In certain embodiments, the keratin-containing material has a particle size distribution ranging from about 95 μm to about 160 μm. 10Particle size ranges from about 15 μm to about 25 μm, d 50 Particle size ranging from about 45 μm to about 55 μm, and / or d 90 The particle size distribution ranges from about 90 μm to about 110 μm.

[0030] After the hydrolysis step, the hydrolyzed keratin-containing material can be subjected to one or more steps of drying, concentrating, refrigeration, and / or freezing. In certain embodiments, the hydrolyzed keratin-containing material can be dried by a suitable drying method to provide ambient shelf life. Suitable drying methods include, but are not limited to, drum drying, spray drying, fluidized bed drying, ring drying, and freeze drying. In certain embodiments, one or more size reduction steps and drying can be performed simultaneously.

[0031] The dried, treated, or hydrolyzed keratin-containing material prepared according to the methods herein may have a lanthionine content of about 1.0% or less, about 0.7% or less, or about 0.5% or less by weight. In certain embodiments, the dried, treated, or hydrolyzed keratin-containing material may have a lanthionine content that is undetectable (i.e., lanthionine is not detectable within the measurement uncertainty) or a lanthionine content ranging from about 0.01% to about 1.0%, about 0.01% to about 0.5%, about 0.05% to about 0.45%, about 0.15% to about 0.4%, about 0.1% to about 0.3%, about 0.2% to about 0.5%, about 0.25% to about 0.45%, about 0.3% to about 0.45%, or about 0.35% to about 0.5% by weight. In certain embodiments, the dried, processed, or hydrolyzed keratin-containing material may have a lanthionine content of less than about 0.4%, less than about 0.35%, or less than about 0.2% by weight, such as from greater than zero to less than about 0.04%, less than about 0.03%, less than about 0.02%, or less than about 0.01% by weight.

[0032] According to non-limiting embodiments of the present disclosure, raw / unprocessed keratin-containing material (e.g., feather material) can optionally undergo a pretreatment step to remove blood and / or other external non-proteinaceous and / or foreign material. After pretreatment, the keratin-containing material can undergo a size reduction step, e.g., coarse grinding, to reduce particle size. The keratin-containing material can then be combined with an acidic solution to provide an acidic pH, e.g., a pH ranging from about 3.5 to about 5. The acidic keratin-containing material can then be reduced to a size ranging from about 30 μm to about 70 μm, and in certain embodiments, from about 40 μm to about 60 μm, or from about 45 μm to about 55 μm. 50 To achieve this particle size, at least one additional size reduction step, for example by ball milling, may be performed. Additionally or alternatively, the d of the acidic keratin-containing material may be 90 The particle size may range from about 80 μm to about 160 μm, and in certain embodiments, from about 95 μm to about 110 μm, or from about 90 μm to about 105 μm. Steam hydrolysis may then be performed while maintaining a pH of about 5 or less. After hydrolysis, the hydrolyzed keratin-containing material may be dried using a suitable drying method as described above. The resulting dried hydrolyzed keratin-containing material may have a lanthionine content of less than about 1.0% by weight, or less than about 0.5% by weight. In certain embodiments, the lanthionine content ranges from about 0.01% to about 0.5% by weight, or from about 0.01% to about 1.0% by weight. Alternatively, the lanthionine content ranges from about 0.5% to about 1.0% by weight.

[0033] According to another embodiment of the present disclosure, raw / unprocessed keratin-containing material (e.g., feather material) can be optionally subjected to a pretreatment step to remove blood and / or other external non-protein and / or foreign material. The keratin-containing material is then cut into granules ranging from about 30 μm to about 70 μm, or from about 40 μm to about 60 μm, or from about 45 μm to about 55 μm. 50To achieve the particle size, one or more size reduction steps may be performed, such as coarse chopping or coarse grinding followed by fine grinding. Additionally or alternatively, the d of the acidic keratin-containing material may be 90 The particle size may range from about 80 μm to about 160 μm, or from about 95 μm to about 110 μm, or from about 90 μm to about 105 μm. The keratin-containing particles may then be combined with an acidic solution to provide an acidic pH, for example, a pH ranging from about 3.5 to about 5. The acidic keratin-containing particles may then undergo steam hydrolysis while maintaining a pH of about 5 or less. After hydrolysis, the hydrolyzed keratin-containing particles may be dried using a suitable drying method as described above. The resulting dried hydrolyzed keratin-containing particles may have a lanthionine content of less than about 1.0% by weight, or less than about 0.5% by weight. In certain embodiments, the lanthionine content ranges from about 0.01% to about 0.5% by weight, or from about 0.01% to about 1.0% by weight. Alternatively, the lanthionine content ranges from about 0.01% to about 1.0% by weight.

[0034] According to another embodiment of the present disclosure, the raw / unprocessed keratin-containing material (e.g., feather material) can optionally undergo a pretreatment step to remove blood and / or other external non-protein and / or foreign material. Optionally, after pretreatment, the keratin-containing material can undergo one or more size reduction steps, such as coarse cutting or coarse grinding, to reduce particle size. The keratin-containing material can then be combined with an acidic solution to provide an acidic pH, e.g., a pH ranging from about 3.5 to about 5. The acidic keratin-containing material can then undergo steam hydrolysis while maintaining a pH of about 5 or less. The hydrolyzed keratin-containing material can then be reduced to keratin particles ranging from about 30 μm to about 70 μm, or from about 40 μm to about 60 μm, or from about 45 μm to about 55 μm. 50 To achieve this particle size, one or more size reduction steps, such as ball milling or other suitable methods, may be used. Additionally or alternatively, the hydrolyzed keratin-containing material may be subjected to 90The particle size may range from about 80 μm to about 160 μm, or from about 95 μm to about 110 μm, or from about 90 μm to about 105 μm. After hydrolysis, the hydrolyzed keratin-containing material may be dried using a suitable drying method as described above. The resulting dried hydrolyzed keratin-containing material may have a lanthionine content of less than about 1.0% by weight, or less than about 0.5% by weight. In certain embodiments, the lanthionine content ranges from about 0.01% to about 0.5% by weight, or from about 0.01% to about 1.0% by weight. Alternatively, the lanthionine content ranges from about 0.01% to about 1.0% by weight.

[0035] The hydrolyzed keratin-containing material (e.g., dried hydrolyzed keratin-containing material) prepared according to the present disclosure can be useful in food compositions, including pet food products. The relatively low lanthionine content can avoid the deleterious effects associated with foods containing high amounts of lanthionine. In certain embodiments, high lanthionine content in pet food compositions is often associated with poor and unacceptable fecal quality in pets, such as soft feces, loose stools, diarrhea, etc.

[0036] The relatively low lanthionine content achieved by the methods herein allows for a relatively high amount of keratin-containing material in a pet food composition that does not contain a relatively high amount of lanthionine. The lanthionine content in commercially available feather meal is typically greater than about 1% by weight, for example, ranging from about 1% to about 3% or more by weight, with an average value of about 2% by weight.

[0037] Table 1 provides guidelines for meal feathers (FM) given as a weight percent of dry pet food for dogs and cats based on the predicted lanthionine content in the meal feathers and the predicted effect on pet feces and stool quality. Evaluation of pet feces (determined as unacceptable or acceptable) is based on the following rating / scoring system: 1=hard, dry pellets: small hard chunks; 2=hard, formed dry feces: firm but remains soft; 3=soft, formed, moist: softer feces that maintains shape; 4=soft, unformed: feces that takes the shape of the container, pudding-like; 5=watery: pourable liquid. For certain embodiments of the present disclosure, feces quality values ​​below about 2 and / or above about 4 are considered unacceptable.

[0038] A lanthionine content of about 0.2% by weight or less, such as about 0.15% by weight or less, about 0.1% by weight or less, or about 0.05% by weight or less, in the pet food composition is expected to produce or contribute to acceptable stool / feces quality. A lanthionine content of more than about 0.2% by weight in the pet food composition is expected to produce or contribute to softer stool that falls outside the acceptable standards for stool / feces quality.

[0039] Table 1 provides guidelines for including feather meal in pet food compositions. A lanthionine (LAN) content of about 2% by weight in feather meal (FM) is assumed for comparison purposes, without considering other contributors to the lanthionine level, such as poultry meal, chicken meal, and chicken-derived meal. Table 1 shows that using more than about 5% by weight of feather meal with about 2% lanthionine results in unacceptable fecal quality and appears to limit the amount of keratin protein that can be used. In the present disclosure, a lower lanthionine content is recognized, so that a larger amount of keratin protein can be used in addition to and / or in place of or in partial replacement of animal protein.

[0040] [Table 1]

[0041] As previously mentioned, the present disclosure includes compositions comprising hydrolyzed keratin-containing materials. In certain embodiments of the present disclosure, the pet food composition may include up to about 0.2% by weight of lanthionine. In certain embodiments, the pet food composition may include up to about 0.1% by weight of lanthionine, such as about 0.01% to about 0.1% by weight of lanthionine.

[0042] The hydrolyzed keratin-containing material herein is used in pet food compositions to partially replace other protein sources, such as poultry meal, chicken meal, chicken-derived meal, turkey, beef, pork, lamb, venison, duck, salmon, other dried animal protein materials, and / or vegetable protein materials (e.g., corn gluten meal, wheat gluten, etc.). In certain embodiments, the composition comprises up to about 20% by weight of the hydrolyzed keratin-containing material, based on the total weight of the composition. In certain embodiments, the composition may comprise from greater than zero to about 20% by weight or less, from about 1% to about 18%, from about 5% to about 15%, from about 10% to about 15%, from about 16% to about 20%, from about 8% to about 12%, from about 3% to about 7%, from about 1% to about 6%, or from about 12% to about 16% by weight of hydrolyzed keratin-containing material, based on the total weight of the composition (e.g., pet food composition). Additional components of the composition include combinations of carbohydrates, lipids, vitamins, fiber (e.g., crude fiber), and / or minerals. In certain embodiments, carbohydrates include, but are not limited to, corn, rice, wheat, sorghum, and barley. In certain embodiments, lipids include, but are not limited to, poultry fat, beef tallow, and vegetable oils. In certain embodiments, compositions according to the present disclosure comprise about 1% to about 20% by weight of dry hydrolyzed keratin-containing material, about 5% to about 35% by weight of another protein source (e.g., about 10% to about 25% by weight, or about 15% to about 30% by weight), about 30% to about 60% by weight of carbohydrate (e.g., about 40% to about 50% by weight, or about 45% to about 55% by weight), and / or about 2% to about 10% by weight of lipid (e.g., about 4% to about 8% by weight, or about 5% to about 7% by weight). In certain embodiments, compositions may comprise about 1% to about 10% by weight of dry hydrolyzed keratin-containing material, about 5% to about 35% by weight of another protein source, about 45% to about 50% by weight of carbohydrate, and about 5% to about 7% by weight of lipid. In such embodiments, the other protein source can be animal or plant based.

[0043] The improved digestibility of keratin-containing materials by the methods of the present disclosure can be quantified using Boisen digestibility (also known as ileal digestibility), a parameter described by Boisen and Fernandez (Animal Feed Science and Technology, 68:277-286, 1997). The Boisen digestibility of hydrolyzed keratin-containing materials of the present disclosure can be inversely proportional to size reduction. In certain embodiments, the Boisen digestibility of keratin-containing materials can increase as the size of the particles decreases. Boisen digestibility is determined by an in vitro analytical method, in which an enzymatic reaction is used to simulate the digestive conditions of the stomach and subsequent small intestine. Boisen digestibility can be measured by simulating gastric digestion (pepsin) followed by small intestinal digestion (pancreatin) to determine the amount of undigested protein remaining.

[0044] The steps are as follows: Prepare a sample solution by combining 1 g of dry sample (dried hydrolyzed keratin-containing material) with 0.1 M phosphate buffer (pH 6) and 0.2 N hydrochloric acid (HCl), then adjusting the pH to 2 ± 0.02 using 1 N HCl and / or 1 N NaOH. Add 1 mL of pepsin solution (10 mg / mL) and incubate at 39°C for 6 hours under constant stirring. Adjust the pH to 6.8±0.2 using 1N HCl solution and / or 1N NaOH. Add 1 mL of aqueous pancreatin solution (50 mg / mL) and incubate at 39°C for 18 hours under constant stirring. Add 5 mL of 20% sulfosalicylic acid solution, leave at room temperature (25°C) for 1 hour, then filter to collect the precipitate (undigested protein source); rinse with water if necessary to collect all the precipitate. The precipitate is dried overnight at about 100°C and then weighed.

[0045] Boisen digestibility is calculated as follows: Boisen digestibility=((AB) / A) * 100% Where A=protein in the original sample (g) and B=protein in the precipitate (g) / 100.

[0046] The Boisen digestibility of the hydrolyzed keratin-containing material prepared according to the methods herein can be greater than about 70%, such as ranging from about 70% to about 90%, for example, the Boisen digestibility ranges from about 75% to about 85%.

[0047] Although the principles of the present disclosure have been described herein with reference to exemplary compositions and methods, it should be understood that the present disclosure is not limited thereto.Those skilled in the art who have access to the teachings provided herein will recognize additional modifications, applications, embodiments, and permutations of equivalents that all fall within the scope of the embodiments described herein.Therefore, the present disclosure should not be construed as being limited by the foregoing description.

[0048] Other exemplary embodiments of the present disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the exemplary embodiments disclosed therein. The specification and examples are considered as exemplary only, and it is intended that departures can be made in form and detail without departing from the scope and spirit of the disclosure as defined by the following claims.

[0049] Preferred embodiments of the present invention will be described below in detail.

[0050] EMBODIMENT 1 1. A method for preparing a hydrolyzed keratin-containing material, comprising: combining the keratin-containing material with an acid; treating the keratin-containing material with steam hydrolysis; and The particle size of the keratin-containing material is d 50 reducing the particle size to The method includes:

[0051] EMBODIMENT 2 2. The method of embodiment 1, wherein the keratin-containing material is combined with the acid to achieve a pH ranging from about 2 to about 5 before and / or during treatment by steam hydrolysis.

[0052] EMBODIMENT 3 3. The method of claim 1 or 2, wherein the particle size reduction step occurs before the combining with acid step, before the steam hydrolysis step, and / or after the steam hydrolysis step.

[0053] EMBODIMENT 4 4. The method of any one of the preceding claims, wherein the steam hydrolysis step is carried out at a pressure of about 0 to about 100 psig (about 0 to 790801 Pa).

[0054] EMBODIMENT 5 5. The method of any one of the preceding claims, wherein the keratin-containing material comprises feathers, hair, wool, beaks, hides, bristles, horns, hooves, pincers, claws, scales, or mixtures thereof.

[0055] EMBODIMENT 6 6. The method of any one of claims 1 to 5, wherein the hydrolyzed keratin-containing material comprises no more than 1.0% by weight of lanthionine, optionally no more than 0.5% by weight of lanthionine, based on the total weight of the hydrolyzed keratin-containing material.

[0056] EMBODIMENT 7 7. A hydrolyzed keratin-containing material prepared according to the method of any one of embodiments 1 to 6.

[0057] EMBODIMENT 8 8. The hydrolyzed keratin-containing material of embodiment 7, wherein the hydrolyzed keratin-containing material has a lanthionine content of 0.25% by weight or less, based on the total weight of the hydrolyzed keratin-containing material.

[0058] EMBODIMENT 9 The hydrolyzed keratin-containing material has a diameter ranging from about 1 μm to about 30 μm. 10 particle size, and / or d ranging from about 80 μm to about 160 μm 90 and / or said d 50 9. The hydrolyzed keratin-containing material of embodiment 7 or 8, wherein the particle size ranges from about 30 μm to about 70 μm.

[0059] EMBODIMENT 10 10. The hydrolyzed keratin-containing material of any one of embodiments 7 to 9, wherein the hydrolyzed keratin-containing material has a Boisen digestibility of about 70% to about 90%.

[0060] EMBODIMENT 11 11. A composition comprising the hydrolyzed keratin-containing material according to any one of embodiments 7 to 10, wherein the composition is a pet food composition.

[0061] EMBODIMENT 12 The composition of embodiment 11, wherein the composition comprises from about 1% to about 20% by weight of the hydrolyzed keratin-containing material.

[0062] EMBODIMENT 13 The composition of embodiment 11 or 12, wherein the composition comprises 0.2% by weight or less of lanthionine, such as about 0.01% to 0.2% by weight of lanthionine, based on the total weight of the composition.

[0063] EMBODIMENT 14 14. The composition of any one of embodiments 11 to 13, wherein the hydrolyzed keratin-containing material is hydrolyzed feather meal.

[0064] EMBODIMENT 15 15. The composition of any one of embodiments 11 to 14, wherein the composition further comprises at least one protein source other than the hydrolyzed keratin-containing material.

[0065] EMBODIMENT 16 The composition of embodiment 15, wherein the at least one protein source other than the hydrolyzed keratin-containing material comprises an animal protein, such as chicken, turkey, beef, pork, lamb, venison, duck, or salmon, and / or a vegetable protein, such as corn gluten flour or wheat gluten.

[0066] EMBODIMENT 17 The composition of any one of embodiments 11 to 16, wherein the composition further comprises at least one carbohydrate, such as corn, rice, wheat, sorghum, or barley, and / or at least one lipid, such as poultry fat, beef tallow, or vegetable oil.

[0067] EMBODIMENT 18 A method for improving fecal quality in an animal, comprising administering to the animal a composition according to any one of embodiments 11 to 17.

[0068] EMBODIMENT 19 The method of embodiment 18, wherein the composition is a dry pet food.

[0069] EMBODIMENT 20 The method of embodiment 18 or 19, wherein the animal is a dog or a cat.

[0070] EMBODIMENT 21 21. The method of any one of embodiments 18 to 20, wherein the animal has a fecal quality value of about 2 to about 4.

[0071] EMBODIMENT 22 Use of the composition according to any one of embodiments 11 to 17 for improving the quality of feces in an animal, optionally wherein the animal is a dog or a cat.

[0072] EMBODIMENT 23 The use of embodiment 22, wherein the animal has a feces quality value of about 2 to about 4.

[0073] EMBODIMENT 24 A hydrolyzed keratin-containing material comprising no more than 1.0% by weight of lanthionine, optionally no more than 0.5% by weight of lanthionine, based on the total weight of the hydrolyzed keratin-containing material, and having a diameter ranging from about 1 μm to about 30 μm. 10 Particle size, ranging from about 80 μm to about 160 μm 90 particle size, and / or d ranging from about 30 μm to about 70 μm 50 A hydrolyzed keratin-containing material having a particle size.

[0074] EMBODIMENT 25 25. The hydrolyzed keratin-containing material of embodiment 24, wherein the hydrolyzed keratin-containing material comprises hydrolyzed feather meal.

[0075] EMBODIMENT 26 about 1% to about 20% by weight of a hydrolyzed keratin-containing material, and at least 5% by weight of a protein source other than the hydrolyzed keratin-containing material; A composition comprising: The composition is a pet food composition, The composition comprises 0.2% by weight or less of lanthionine, such as 0.1% by weight or less of lanthionine, based on the total weight of the composition.

[0076] EMBODIMENT 27 27. The composition of embodiment 26, wherein the protein source other than the hydrolyzed keratin-containing material comprises an animal protein such as chicken, turkey, beef, pork, lamb, venison, duck, or salmon, and / or a vegetable protein such as corn gluten flour or wheat gluten.

[0077] EMBODIMENT 28 The composition of embodiment 26 or 27, wherein the composition further comprises at least one carbohydrate, such as corn, rice, wheat, sorghum, or barley, and / or at least one lipid, such as poultry fat, beef tallow, or vegetable oil.

Claims

1. 1. A method for preparing a hydrolyzed keratin-containing material, comprising: combining the keratin-containing material with an acid; treating the keratin-containing material with steam hydrolysis; and The particle size of the keratin-containing material is d 100 μm or less ５０ reducing the particle size to The method includes:

2. 2. The method of claim 1, wherein the keratin-containing material is combined with the acid to achieve a pH ranging from 2 to 5 before and / or during treatment by steam hydrolysis.

3. 3. The method of claim 1 or 2, wherein the particle size reduction step occurs before the step of combining with acid, before the step of treating with steam hydrolysis, and / or after the step of treating with steam hydrolysis.

4. 3. The method of claim 1 or 2, wherein the steam hydrolysis step is carried out at a pressure of from 0 to 100 psig (0 to 790,801 Pa).

5. 3. The method of claim 1 or 2, wherein the keratin-containing material comprises feathers, hair, wool, beaks, hides, bristles, horns, hooves, pincers, claws, scales, or mixtures thereof.

6. 3. The method of claim 1 or 2, wherein the hydrolyzed keratin-containing material comprises no more than 1.0% by weight of lanthionine, based on the total weight of the hydrolyzed keratin-containing material.

7. A hydrolyzed keratin-containing material mixed with an acid, the hydrolyzed keratin-containing material having a d50 particle size of 100 μm or less.

8. 8. The hydrolyzed keratin-containing material of claim 7, wherein the hydrolyzed keratin-containing material has a lanthionine content of 0.25% by weight or less, based on the total weight of the hydrolyzed keratin-containing material.

9. The hydrolyzed keratin-containing material has a diameter ranging from 1 μm to 30 μm. １０ Particle size and / or d ranging from 80 μm to 160 μm ９０ and / or said d ５０ 9. The hydrolyzed keratin-containing material according to claim 7 or 8, wherein the particle size ranges from 30 μm to 70 μm.

10. 9. The hydrolyzed keratin-containing material of claim 7 or 8, wherein the hydrolyzed keratin-containing material has a Boisen digestibility of between 70% and 90%.

11. A composition comprising the hydrolyzed keratin-containing material of claim 7 or 8, said composition being a pet food composition.

12. The composition of claim 11 , wherein the composition comprises from 1% to 20% by weight of the hydrolyzed keratin-containing material.

13. The composition of claim 11, wherein the composition comprises no more than 0.2% by weight of lanthionine, based on the total weight of the composition.

14. The composition of claim 11 , wherein the hydrolyzed keratin-containing material is hydrolyzed feather meal.

15. The composition of claim 11 , wherein said composition further comprises at least one protein source other than said hydrolyzed keratin-containing material.

16. 16. The composition of claim 15, wherein the at least one protein source other than the hydrolyzed keratin-containing material comprises an animal protein comprising chicken, turkey, beef, pork, lamb, venison, duck, or salmon, and / or a vegetable protein comprising corn gluten flour or wheat gluten.

17. 12. The composition of claim 11, wherein the composition further comprises at least one carbohydrate comprising corn, rice, wheat, sorghum, or barley, and / or at least one lipid comprising poultry tallow, beef tallow, or vegetable oil.

18. 12. A method for improving fecal quality in an animal, comprising administering to the animal a composition according to claim 11.

19. 20. The method of claim 18, wherein the composition is a dry pet food.

20. 20. The method of claim 18, wherein the animal is a dog or a cat.

21. 20. The method of claim 18, wherein the animal's feces quality value is between 2 and 4.

22. 12. Use of the composition according to claim 11 for improving the quality of animal droppings.

23. 23. The use of claim 22, wherein the animal's feces quality value is between 2 and 4.

24. A hydrolyzed keratin-containing material, comprising 1.0% by weight or less of lanthionine, based on the total weight of the hydrolyzed keratin-containing material, and a d １０ Particle size, ranging from 80 μm to 160 μm ９０ Particle size and / or d ranging from 30 μm to 70 μm ５０ A hydrolyzed keratin-containing material having a particle size.

25. 25. The hydrolyzed keratin-containing material of claim 24, wherein the hydrolyzed keratin-containing material comprises hydrolyzed feather meal.

26. A method for producing a composition comprising: at least 5% by weight of a protein source other than the hydrolyzed keratin-containing material; A composition comprising: The composition is a pet food composition, The composition comprises 0.2% by weight or less of lanthionine, based on the total weight of the composition.

27. 27. The composition of claim 26, wherein the protein source other than the hydrolyzed keratin-containing material comprises an animal protein comprising chicken, turkey, beef, pork, lamb, venison, duck, or salmon, and / or a vegetable protein comprising corn gluten flour or wheat gluten.

28. 28. The composition of claim 26 or 27, wherein the composition further comprises at least one carbohydrate comprising corn, rice, wheat, sorghum, or barley, and / or at least one lipid comprising poultry tallow, beef tallow, or a vegetable oil.

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