JP2018113931A - Method of producing feed pellet for ruminants - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide ruminant feed having high nutritive value and roughage characteristics as well as long preservation period.SOLUTION: The present invention provides a method of producing a feed pellet for ruminants containing a kraft pulp, the method comprising a) pelletizing kraft pulp, and b) a sterilization step of heating a pelletized kraft pulp in a range where a heating rate s represented by the following formula 1 ranges from 5°C/second or more to 200°C/second or less. s(°C/sec.)=ΔT/t (formula 1) (ΔT is the increase temperature of a kraft pulp and t is a retention time within a die hole.)SELECTED DRAWING: None

Description

  The present invention relates to a method for producing ruminant feed pellets.

  In general, in the pastoral field, concentrated feed with high nutritional value is often used together with roughage such as pasture for the purpose of increasing the milk yield and weight gain of livestock.

  Concentrated feed contains a lot of easily digestible carbohydrates (starch, etc.) such as corn, wheat, and soybean, while roughage is fermented hay (hay, straw) and pastures that have been green-cut. Mainly (silaged).

  Ruminants are able to ingest and digest forage because they have lumens (the rumen). Rumen occupies the largest volume of the rumen's multiple stomachs and contains abundant microorganisms (lumen microorganisms) that can degrade (rumen fermentation) indigestible polysaccharides such as cellulose and hemicellulose in roughage. It is.

  However, cellulose and hemicellulose in roughage often bind to lignins and exist as lignin-cellulose complexes and lignin-hemicellulose complexes, respectively. Such a complex may not be sufficiently decomposed in rumen fermentation, and the rough feed has a problem that feed efficiency tends to be insufficient. Moreover, since an increase in the amount of undigested materials causes an increase in the amount of feces, it has been considered undesirable from an environmental point of view.

  Furthermore, roughage is easily affected by the yield and pattern of pasture and its supply is unstable. In particular, Japan relies on imports for most of the roughage, so price fluctuations are generally large, and it may be difficult to import due to various circumstances in the exporting country, which may put pressure on ranch management.

  For this reason, a ruminant feed that can be replaced with grass, has excellent feed efficiency, is inexpensive, and can be stably obtained is desired.

  Here, in order to increase the nutrient concentration in the feed, it is generally performed to mix a concentrated feed containing a large amount of easily digestible carbohydrates (starch) into the rough feed. In order to maintain the milk yield of dairy livestock or to maintain the increase in meat livestock, it is necessary to increase the feed intake, but the energy demands associated with the increase in milk yield and physique increase. This is because the rate of increase exceeds the rate of increase in the amount of ingested feed. However, carbohydrates such as starch in concentrated feeds can drastically lower the rumen pH, resulting in the occurrence of rumen acidosis. Rumen acidosis is a type of ruminant disease caused by rapid intake of carbohydrate-rich cereals, concentrates, fruits, and the like. In rumen acidosis, gram-positive lactic acid producing bacteria, particularly Streptcoccus bovis and Lactobacillus spp. Microorganisms increase in the rumen, resulting in abnormal accumulation of lactic acid or volatile fatty acid (VFA), and the pH in the rumen Decrease (pH 5 or less). The result is a decrease or disappearance of protozoa (protozoa) and certain bacteria in the lumen. In particular, acute acidosis is extremely dangerous because it causes rumen congestion and dehydration (a large amount of body fluid moves into the stomach as the gastric osmotic pressure increases), and coma and death.

  In order to prevent rumen acidosis, it is important to avoid sudden changes in feed composition, stabilize rumen fermentation, and reduce pH fluctuations. In addition, since saliva contains sodium bicarbonate and contributes to pH adjustment, it is also important to supply a feed that can secrete saliva with sufficient rumination. However, there is also a concern that rumen acidosis is feared, and if the nutritional value of the feed is lowered, energy is insufficient and milk production is reduced.

  As a feed for preventing rumen acidosis, Patent Document 1 discloses a livestock feed that is pulverized and pulverized by applying a high impact force to a woody material.

  Moreover, regarding the pelletized feed, Patent Document 2 proposes that the processed food residue is pelletized to produce the feed.

  Furthermore, Patent Document 3 describes that lignocellulose biomass is pelletized to produce ruminant feed (Japanese Patent Publication No. 2013-518880).

  Patent Document 4 describes a method for improving storage stability in which animal feed is sterilized by contact with ozone in order to prevent decay.

JP 2011-82381 A JP-A-10-75719 Special table 2013-518880 gazette JP-A-8-131088

  In general, high-concentration feed such as corn is highly fermentable and has a high nutritional value. It is also known to cause various metabolic and reproductive disorders before and after parturition. Also, feed pellets are generally difficult to reserve due to fast decay. It is necessary to feed ruminants as soon as possible after production.

  Accordingly, an object of the present invention is to provide a ruminant feed that has high nutritional value, has characteristics of a rough feed, and has a long storage period.

  The inventors of the present invention diligently studied the above problems, and found that pellets produced from a lignocellulosic material as a raw material can be pelletized, and at the same time, feed pellets with good storage stability that can promote rumination of ruminants can be produced. The present invention has been completed.

That is, the present invention includes the following inventions.
(1) In the production of ruminant feed pellets containing kraft pulp,
a) pelletizing kraft pulp;
b) The sterilization process which heat-processes the pelletized kraft pulp in the range whose temperature increase rate s represented by following formula 1 is 5 degrees C / sec or more and 200 degrees C / sec or less,
A method for producing ruminant feed pellets.
s (° C./sec.)=ΔT/t (Formula 1)
(ΔT is the rising temperature of the kraft pulp, and t is the residence time in the die hole.)
(2) The method for producing ruminant feed pellets according to claim 1, wherein the step of pelletizing the kraft pulp and the sterilization step of heat-treating the pelletized kraft pulp are performed simultaneously.
(3) The method for producing ruminant feed pellets according to claim 1 or 2, wherein the length of the pellets is 1 to 200 mm.
(4) The method for producing feed pellets for mammals according to any one of claims 1 to 3, wherein the pellet has a diameter of 3 to 10 mm.
(5) The manufacturing method of the feed pellet for rodents in any one of Claims 1-4 whose moisture content of a pellet is 35 mass% or less.

  According to the present invention, a feed having good storage stability can be obtained in the form of pellets that are highly ruminant and easy to handle. Moreover, since the ruminant feed of the present invention can be produced from a lignocellulose raw material such as wood, it can be stably supplied.

  The ruminant feed pellet of the present invention is applied to ruminants. Examples of ruminants include cows such as dairy cows and fattening cows, sheep, and goats. There is no particular limitation on the time when the feed of the present invention is fed to ruminants, that is, the age, physique, health status, etc. of ruminants to which the feed is applied. For example, it is considered that there are applications from calves in adulthood to adult cattle. .

The ruminant feed pellet of the present invention contains kraft pulp, but preferably contains 50% by mass or more, more preferably 80% by mass or more, and may consist of only kraft pulp. Further, the lower limit of the copper value of kraft pulp is not particularly limited, but it can be, for example, 5 or more and less than 100, preferably 5 or more and 45 or less, and more preferably 5 or more and less than 15. Kraft pulp subjected to oxygen delignification treatment with a copper number of 5 or more and less than 15 is particularly preferred. (Limited to the lower limit, added as above. If the flow of explanation seems unnatural, you can delete it. Can you judge?)
The ruminant feed pellets of the present invention contain kraft pulp, but pulps produced by other known pulping methods can be used in combination. For example, both mechanical pulp and chemical pulp are applicable. Examples of mechanical pulp include groundwood pulp (GP), refiner groundwood pulp (RGP), thermomechanical pulp (TMP), chemithermomechanical pulp (CTMP), and the like. Examples of the chemical pulp include kraft pulp (KP), dissolved kraft pulp (DKP), sulfite pulp (SP), and dissolved sulfite pulp (DSP). Either bleached pulp or unbleached pulp can be used. Of these, oxygen delignified chemical pulp and bleached chemical pulp are preferred.

  As the raw material wood, for example, hardwood, conifer, miscellaneous tree, bamboo, kenaf, bagasse, empty bunch after palm oil extraction can be used. Specifically, the broad-leaved trees include beech, china, birch, poplar, eucalyptus, acacia, oak, itayaka maple, senoki, elm, giraffe, honoki, willow, sen, basamushi, konara, kunugi, tochinoki, zelkova, mizume, mizuzuki Aodamo etc. are exemplified. As conifers, cedar, spruce, larch, black pine, todomatsu, himekomatsu, yew, neko, spruce, iramimi, fir, sawara, togasawara, asunaro, hiba, tsuga, kotsutsuga, hinoki, yew, yellowtail, spruce (Beihiba), Lawson Hinoki (Beihi), Douglas Fir (Beimatsu), Sitka Spruce (Beisuhi), Radiata Pine, Eastern Spruce, Eastern White Pine, Western Larch, Western Fir, Western Hemlock, Tamarack and the like.

Pulping process The feed pellet in the present invention contains kraft pulp obtained by kraft cooking of a lignocellulose raw material, particularly preferably wood-derived kraft pulp. In particular, in the present invention, by using kraft pulp having a Canadian standard freeness (CSF) of 400 ml or more, a digestion rate in rumen rumen is moderated, and feed pellets that promote rumination in rumen are produced. Is possible. In a preferred embodiment, the Canadian standard freeness of kraft pulp used in the present invention is 450 ml or more, and may be 500 ml or more or 550 ml or more. In general, the Canadian standard freeness of kraft pulp can be reduced by known methods.

  When producing kraft pulp from wood chips, the wood pulp is put into a digester along with the cooking liquor and used for kraft cooking. Moreover, you may use for cooking of correction craft methods, such as MCC, EMCC, ITC, and Lo-solid. Also, there are no particular limitations on cooking types such as 1 vessel liquid phase type, 1 vessel gas phase / liquid phase type, 2 vessel liquid phase / gas phase type, and 2 vessel liquid phase type. That is, the step of impregnating and holding the alkaline aqueous solution of the present application may be installed separately from the conventional apparatus or part for the permeation treatment of the cooking liquid. Preferably, the unbleached pulp that has been cooked is washed with a washing device such as a diffusion washer after extracting the cooking liquor.

  The kraft cooking process can be performed by putting the pre-hydrolyzed wood chips together with the kraft cooking liquid in a pressure resistant container, but the shape and size of the container are not particularly limited. The liquid ratio between the wood chip and the chemical solution can be, for example, 1.0 to 5.0 L / kg, preferably 1.5 to 4.5 L / kg, and more preferably 2.0 to 4.0 L / kg. .

  Moreover, in this invention, the alkaline cooking liquid containing 0.01-1.5 mass% quinone compound per absolutely dry chip | tip can also be added to a digester. If the addition amount of the quinone compound is less than 0.01% by mass, the addition amount is too small to reduce the kappa number of the pulp after cooking, and the relationship between the kappa number and the pulp yield is not improved. Furthermore, the reduction of wrinkles and the suppression of the decrease in viscosity are insufficient. Moreover, even if the addition amount of a quinone compound exceeds 1.5 mass%, the further reduction of the kappa number of the pulp after cooking and the improvement of the relationship between a kappa number and a pulp yield are not recognized.

  The quinone compound used is a quinone compound, hydroquinone compound or precursor thereof as a so-called known cooking aid, and at least one compound selected from these can be used. Examples of these compounds include anthraquinone, dihydroanthraquinone (for example, 1,4-dihydroanthraquinone), tetrahydroanthraquinone (for example, 1,4,4a, 9a-tetrahydroanthraquinone, 1,2,3,4-tetrahydroanthraquinone). Methyl anthraquinone (eg 1-methyl anthraquinone, 2-methyl anthraquinone), methyl dihydroanthraquinone (eg 2-methyl-1,4-dihydroanthraquinone), methyl tetrahydroanthraquinone (eg 1-methyl-1,4,4a) , 9a-tetrahydroanthraquinone, 2-methyl-1,4,4a, 9a-tetrahydroanthraquinone) and the like, anthrahydroquinone (generally 9,10-dihydroxyanthracene), Tyranthrahydroquinone (for example, 2-methylanthrahydroquinone), dihydroanthrahydroanthraquinone (for example, 1,4-dihydro-9,10-dihydroxyanthracene) or an alkali metal salt thereof (for example, disodium salt of anthrahydroquinone, 1 , 4-dihydro-9,10-dihydroxyanthracene disodium salt), and precursors such as anthrone, anthranol, methylanthrone, and methylanthranol. These precursors have the potential to convert to quinone compounds or hydroquinone compounds under cooking conditions.

When the wood chip is a conifer, the cooking solution preferably has an active alkali addition rate (AA) per weight of the dry wood chip of 16 to 22% by mass. If the active alkali addition rate is less than 16% by mass, the removal of lignin and hemilulose becomes insufficient, and if it exceeds 22% by mass, the yield and quality are reduced. Here, the active alkali addition rate is obtained by converting the total addition rate of NaOH and Na ₂ S as the addition rate of Na ₂ O, and multiplying NaOH by 0.775 and Na ₂ S by 0.795. Therefore, it can be converted into the addition rate of Na ₂ O. The degree of sulfidation is preferably in the range of 20 to 35%. In the region where the sulfidity is less than 20%, the delignification property is lowered, the pulp viscosity is lowered, and the drought rate is increased.

  Kraft cooking is preferably performed in a temperature range of 120 to 180 ° C, more preferably 140 to 160 ° C. If the temperature is too low, delignification (decrease in the kappa number) is insufficient, while if the temperature is too high, the degree of polymerization (viscosity) of cellulose decreases. The cooking time in the present invention is the time from when the cooking temperature reaches the maximum temperature until the temperature starts to decrease, and the cooking time is preferably 60 minutes or more and 600 minutes or less, and 120 minutes or more and 360 minutes or less. Is more preferable. If the cooking time is less than 60 minutes, pulping does not proceed, and if it exceeds 600 minutes, the pulp production efficiency deteriorates, which is not preferable.

  Moreover, the kraft cooking in this invention can set process temperature and process time by setting H factor (Hf) as a parameter | index. The H factor is a standard representing the total amount of heat given to the reaction system during the cooking process, and is represented by the following equation. The H factor is calculated by time integration from the time when chips and water are mixed until the end of cooking. The H factor is preferably 300 to 2000.

Hf = ∫exp (43.20-16113 / T) dt
[Wherein T represents an absolute temperature at a certain point]
In the present invention, the unbleached (unbleached) pulp obtained after cooking can be subjected to various treatments as necessary. For example, bleaching can be performed on unbleached pulp obtained after kraft cooking.

  The pulp obtained by kraft cooking can be subjected to oxygen delignification treatment. As the oxygen delignification used in the present invention, a known medium concentration method or high concentration method can be applied as it is. In the case of the medium concentration method, the pulp concentration is preferably 8 to 15% by mass, and in the case of the high concentration method, it is preferably performed at 20 to 35% by mass. As the alkali in oxygen delignification, sodium hydroxide and potassium hydroxide can be used. As oxygen gas, oxygen from a cryogenic separation method, oxygen from PSA (Pressure Swing Adsorption), VSA (Vacuum Swing Adsorption) Oxygen etc. from) can be used.

The reaction conditions for the oxygen delignification treatment are not particularly limited, but the oxygen pressure is 3 to 9 kg / cm ² , more preferably 4 to 7 kg / cm ² , and the alkali addition rate is 0.5 to 4 mass per pulp dry weight. %, A processing temperature of 80 to 140 ° C., a processing time of 20 to 180 minutes, and other conditions can be known. In the present invention, the oxygen delignification treatment may be performed a plurality of times. Moreover, it is preferable that the copper number of the kraft pulp after performing an oxygen delignification process etc. is 5-15.

  For the purpose of further reducing the kappa number and improving the whiteness, the pulp that has been subjected to oxygen delignification treatment, for example, is then sent to the washing step, and after washing, it is sent to the multistage bleaching step, where the multistage bleaching treatment is performed. It can be carried out. The multi-stage bleaching treatment of the present invention is not particularly limited, but acid (A), chlorine dioxide (D), alkali (E), oxygen (O), hydrogen peroxide (P), ozone (Z), It is preferable to combine a known bleaching agent such as peracid and a bleaching aid. For example, the first stage of the multistage bleaching process uses a chlorine dioxide bleaching stage (D) or an ozone bleaching stage (Z), the second stage is an alkali extraction stage (E), the hydrogen peroxide stage (P), the third stage or later. A bleaching sequence using chlorine dioxide or hydrogen peroxide is preferably used. The number of stages after the third stage is not particularly limited, but considering energy efficiency, productivity, etc., it is preferable to finish in three or four stages in total. Further, a chelating agent treatment stage with ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA) or the like may be inserted during the multistage bleaching treatment.

  The feed pellets of the present invention can be fed to ruminants along with other feeds. Other feed ingredients include roughage (eg pasture), concentrated feed (eg corn, wheat and other grains, soybeans and other beans), bran, rice bran, okara, protein, lipid, vitamins, minerals and other additives (preservation) , Coloring agents, fragrances, etc.). These other feed components may be mixed with kraft pulp when pelletizing.

  The ruminant feed pellet of the present invention preferably has a moisture content of 15% or less. By making the moisture content 15% or less, the transportability is improved and the decay by microorganisms can be reduced.

Pelletization process The ruminant feed pellet in this invention can be manufactured by pelletizing the raw material containing a kraft pulp by a well-known method.

  Pelletization is performed by compression molding, and a known apparatus can be used. Although the pelletizer is not particularly limited, for example, a ring die type or flat die type pelletizer can be cited as a suitable example. Specifically, a briquetter (made by Kitagawa Steel Works), a ring die type pelletizer (made by CPM), a flat die type pelletizer (made by Dalton), etc. are desirable.

  Although the shape and size of the pellet are not particularly limited, for example, the diameter of the pellet is preferably 3 to 10 mm. The length of the pellet is preferably 1 to 200 mm, for example, and may be 4 to 80 mm.

  The treatment conditions by the pelletizer in the present invention are not particularly limited, but the effective hole length of the die is, for example, 5 mm or more, preferably 15 mm or more, more preferably 25 mm or more. In addition, prior to pelletizing with a pelletizer, kraft pulp may be pretreated using a known moisture adjusting device such as a known mixing / stirring device or mist sprayer, if necessary, such as a paddle mixer. Is possible.

  The moisture content of the kraft pulp before pelletizing can be 35% by mass or less, and preferably 10 to 35% by mass. With such a water content, it is easy to pelletize, and the pulp can be dried at the same time by the heat during pellet molding, which is efficient.

Sterilization process The method for producing ruminant feed according to the present invention includes a sterilization process in which pelletized kraft pulp is heat-treated at a temperature rising rate of 5 ° C./second or more and 200 ° C./second or less.

  In the present invention, the sterilization step for heat treatment at a temperature rising rate of 5 ° C./second or more and 200 ° C./second or less is not particularly limited. For example, using a briquetter or a pelletizer, the step of pelletizing kraft pulp and the step of heat-treating and sterilizing the pelletized kraft pulp can be performed simultaneously. Among these, it is preferable to use a pelletizer. The mechanism by which the pelletizer can be suitably used is not clear, but the kraft pulp is consolidated into a small-diameter die hole under high pressure, and the pressure energy by the power is changed to thermal energy through frictional force, raising the temperature of the entire die, It is considered that the temperature of the formed pellet rises instantaneously.

  In the sterilization step of the present invention, the rate of temperature rise is 5 ° C./second or more and 200 ° C./second or less, preferably 20 ° C./second or more and 200 ° C./second or less, more preferably 50 ° C./second or more and 200 ° C./second or less. . If it is these ranges, sufficient disinfection effect will be acquired and decay with time and generation | occurrence | production of a strange odor will be suppressed.

  The procedure for deriving the rate of temperature increase when the sterilization step of the invention with the temperature increase rate of 5 ° C./second or more and 200 ° C./second or less is performed using a pelletizer will be described below.

  The pelletizer passes through the kraft pulp while being compacted in the die hole, and at that time, the pressure energy converted from the power is converted into thermal energy through frictional force, and the pellet temperature formed until it is released from the outlet of the die hole Rises instantly. In the present invention, this instantaneous increase in pellet temperature is used for sterilization.

  The essential factors related to the performance of the pelletizer include motor capacity (kW), throughput (kg / hr), homogeneous pressure (MPa), die hole diameter (mm), die hole effective length (mm), and other dice There are plate pressure and die hole shape.

Pressure loss Δp / L (MPa / m) per 1 m die hole due to friction on the die hole wall surface of the kraft pulp passing through the die hole having the effective length L (mm) is expressed by Formula 1 from Fanning's formula. expressed. Hereinafter, f is a pipe friction coefficient, and in the Blasius equation, the pipe friction coefficient f is f = 0.0791 Re ^−0.25 between the Reynolds number Re in the turbulent flow region (Re ≦ 1 × 10 ⁵ ). The empirical formula is proposed. In the pelletizer, the flow state when the kraft pulp passes through the die hole is sufficiently in the turbulent flow region. In Equation 1, Re = 1 × 10 ⁵ for convenience in calculating the tube friction coefficient f, and the tube friction coefficient f = 0.004. Got. Hereinafter, the density of kraft pulp is expressed as ρ (kg / m ³ ), the average speed of craft pulp die holes is expressed as u _a (m / sec.), And the diameter of the die holes is expressed as d (mm).
Δp / L = 4f × ρ × u _a ² / (2 (d × 1000) × 1 × 10 ⁶ ) (Formula 1)

In addition, there are die plate pressure and die hole shape as important factors related to the ability of the pelletizer. In addition to the frictional resistance of the die hole, these factors need to be estimated as resistance loss of the die hole. In many cases, it is concealed as know-how in the design of the pelletizer, or its quantification is difficult, and these are defined as a comprehensive die hole length L _X (m) as follows.

At this time, the comprehensive die hole length L _X (m) can be derived from the pressure loss Δp / L per 1 m and the homogeneous pressure (processing pressure) _Ph by the equation 2.
L _X = P _h / (Δp / L) (Formula 2)

Next, the residence time t (sec.) In the die hole is determined from the comprehensive die hole length L _X (m) defined in the present invention and the passing speed u _a (m / sec.) Of the craft pulp die hole. It can be derived from Equation 3. In addition, the said passing speed u _a uses the processing amount per die hole Q (kg / hr), the density ρ (kg / m ³ ), the die hole diameter d (mm), and the circumference ratio π, It can be calculated from Equation 4.
t = L _X / u _a (Formula 3)
u _a = (Q / ρ / 3600) / ((d / 2) ² × π) (Formula 4)

That is, from the equations 2 to 4, the residence time t (sec.) In the die hole can be derived as follows.
t = L _X × (d / 2) ² × π / (Q / ρ / 3600) (Formula 5)

Further, in defining the rate of temperature rise (° C./sec.) In the sterilization process of the present invention, the rising temperature ΔT (° C.) of any fluid is determined by the uniform pressure P (MPa) of the pelletizer and the specific heat C (J / J). g · K) and density ρ (kg / m ³ ).
ΔT = P / (C × ρ / 1000) (Formula 6)

From the residence time t (sec.) In the die hole obtained from Equation 5 and the rising temperature ΔT (° C.) of any kraft pulp obtained from Equation 6, using Equation 7 and any pelletizer The temperature rising temperature s (° C./sec.) During the homogeneous treatment of kraft pulp at an arbitrary temperature can be derived.
Temperature rising rate s (° C./sec.)=ΔT/t (Formula 7)

  However, the specific heat of kraft pulp is measured according to JIS K7123, the specific gravity is measured according to JIS Z7302-9, and the dry rate (water content and solid content concentration) is measured according to JIS P8203. In addition, in the physical property values, in the present invention, when a physical property value (document value) corresponding to an actual processing temperature cannot be found, it is allowable to adopt an estimated value from existing data or an approximate value by rounding off. Is done. For example, when the inlet temperature of the pelletizer is 27 ° C., a physical property value of 30 ° C. is used as an approximate value. Moreover, when the kraft pulp contains other feed raw materials less than 10% by weight, for example, it is assumed that the entire amount of kraft pulp has been processed.

In summary, the heating rate s is expressed as follows.
s (° C./sec.)=ΔT/t (Formula 7)
ΔT is the rising temperature of the kraft pulp and is represented by the following formula 6, and t is the residence time in the die hole and is represented by the following formula 5.
ΔT = P / (C × ρ / 1000) (Formula 6)
P (MPa) is the homogeneous pressure of the pelletizer, C (J / g · K) is the specific heat of the kraft pulp, and ρ (kg / m ³ ) is the density of the kraft pulp.
t = L _X × (d / 2) ² × π / (Q / ρ / 3600) (Formula 5)
L _X (m) is the comprehensive die hole length, d (mm) is the die hole diameter, π is the circumference, Q (kg / hr) is the throughput per die hole, and ρ (kg / m ³ ) Is the density of kraft pulp, and Lx is expressed by the following formula 2.
L _X = P _h / (Δp / L) (Formula 2)
_Ph is a homogeneous pressure (treatment pressure), and Δp / L is a pressure loss per 1 m of die hole, and is expressed by the following formula 1.
Δp / L = 4f × ρ × u _a ² / (2 (d × 1000) × 1 × 10 ⁶ ) (Formula 1)
f is the pipe friction coefficient, and u _a (m / sec.) is the average speed of the kraft pulp passing through the die hole.

As a pressure in the sterilization process of the present invention, the lower limit is preferably 0.8 MPa or more, more preferably 15 MPa or more, and further preferably 25 MPa or more. The upper limit is preferably 200 MPa or less. If it is these ranges, sufficient sterilization effect will be acquired and decay with time and generation | occurrence | production of a bad smell can be suppressed. The device for applying these pressures is not particularly limited, and for example, a pelletizer can be used. The extrusion pressure of the pelletizer cannot usually be measured, but it can be calculated from the cross-sectional area of the pellet, that is, the opening area per hole of the die, the weight of the pressrose and the tightening force when fixing the press roll. it can. That is, it can be expressed by Equation 8 from the pressure P (MPa), the pellet cross-sectional area S (m ² ), the weight of the press roll, and the tightening load F (kgf).

P = F × 9.80665 / S / 10 ⁶ (Formula 8)
As a temperature condition when a pelletizer is used in the sterilization step, the temperature of the kraft pulp is preferably 0 ° C. or higher and more preferably 15 ° C. or higher at the start. Moreover, it is preferable that the temperature after heat processing is 80 degrees C or less. If it is 10 degreeC or more, it can fully sterilize and is preferable. If it is 80 ° C. or higher, there is a possibility that the surface layer of the pellet may be burned after the treatment, which is not preferable.

  When a pelletizer is used in the sterilization process, it is preferable to cool appropriately when the temperature of the pellets after the pelletizer treatment exceeds the outside air temperature.

  In addition, the pelletizer used for the purpose of sterilization in the present invention may be the same as the pelletizer used in the pelletizing treatment process, and even if the pelletizing treatment and the sterilizing treatment in the previous process are discontinuously performed, May also be implemented. When implementing continuously, it is preferable to make the temperature of the kraft pulp provided to a sterilization process into the temperature of 10 degreeC or more.

  The feed pellet for ruminants of the present invention is fed to ruminants, and a feed that can be stored for a long time is preferable for dairy farmers who handle dairy cows, etc., preservatives and antibacterial agents that can affect animal health, Since it can be sterilized without using an antibacterial agent or the like, it can be suitably used for bacteria, calves that do not have sufficient resistance to such drugs, and cattle immediately after birth.

  The present invention will be described in more detail below with reference to experimental examples, but the present invention is not limited to these experimental examples. In the present specification, concentration and% are based on mass unless otherwise specified, and numerical ranges are described as including the end points.

[Example 1}
Put a eucalyptus chip (equivalent to 300 g of dryness) with a radius (Φ) of 9.5 mm to 25.4 mm in a pressure-resistant kettle. Kraft cooking was performed under the conditions to obtain hardwood unbleached kraft pulp (copper number: 17.6, ISO whiteness: 36.4%).
This hardwood unbleached kraft pulp is washed with tap water, adjusted to a concentration of 10%, oxygen addition rate 2.1% (per weight of dry pulp), sodium hydroxide 1.4% (per weight of dry pulp), Oxygen delignification treatment was performed at 100 ° C. for 60 minutes to obtain hardwood oxygen delignification kraft pulp (LOKP, copper number: 11.1, ISO whiteness: 54.7%).
Next, after dewatering LOKP with a centrifugal dehydrator (YS-7SSA, manufactured by Iwatsuki Machine Manufacturing Co., Ltd.) until the water content becomes 30% by weight, Φ6 mm, effective with a ring die type small pelletizer (California pellet mill, motor capacity 30 kW) It processed with the die | dye of thickness 35mm, and it processed to the sterilization process while producing a feed pellet. The total weight of the press roll and the clamping load is 200 kgf, the throughput per die hole is 0.5 kg / hr, and the temperature of the material at the inlet and outlet of the pelletizer before and after the pelletization and sterilization steps is 30 ° C., respectively. It was 88.5 ° C. Further, the rate of temperature increase calculated by the above formula is 15.07 ° C./sec. Met.

[Example 2}
In the pelletization and sterilization steps, feed pellets were obtained in the same manner as in Example 1 except that the treatment amount per hole of the die was 1.0 kg / hr. Moreover, the temperature of the material in the pelletizer inlet_port | entrance and outlet before and after the pelletization and sterilization process at this time was 0 degreeC and 58.2 degreeC, respectively. The temperature increase rate calculated by the above formula is 29.97 ° C./sec. Met.

[Example 3]
In the pelletization and sterilization steps, the feed pellets were prepared in the same manner as in Example 1 except that the weight of the press roll and the tightening load were 330 kgf and the processing amount per hole of the die was 4.0 kg / hr. Obtained. Further, the temperatures of the materials at the inlet and outlet of the pelletizer before and after the pelletization and sterilization steps at this time were 0 ° C. and 96.0 ° C., respectively. Further, the rate of temperature increase calculated by the above formula is 197.79 ° C./sec. Met.

[Comparative Example 1]
In Example 1 above, feed pellets were obtained in the same manner as in Example 1 except that the weight of the press roll of the pelletizer in the sterilization step and the tightening load were 20 kgf. The pellet temperature at the pelletizer outlet at the end of the pelletizing step was 35.8 ° C. Further, the rate of temperature increase calculated by the above formula is 1.507 ° C./sec. Met.

[Comparative Example 2]
In Example 1 above, feed pellets were obtained in the same manner as in Example 1 except that the weight of the press roll of the pelletizer in the sterilization step and the tightening load were 400 kgf. The pellet temperature at the pelletizer exit at the end of the pelletizing process was 116.8 ° C., and the pellet surface was burnt and blackened. Further, the rate of temperature increase calculated by the above formula is 239.75 ° C./sec. Met.

[Comparative Example 3]
In Example 1, except that the pelletizing step and the sterilizing step were omitted and the predetermined step was completed, LOKP dehydrated to 30% by weight was obtained by the same operation as in Example 1.

[Comparative Example 4]
As the mixed feed, TMR (Total Mixed Relation) feed was used for various tests.

[Comparative Example 5]
Bermudagrass hay (manufactured by Takeda, Bermuda Hayvale, USA) was used for various tests as roughage.

<Temperature increase rate>
It was calculated by the method described above. The conditions and results are shown in Table 1. Here, the specific heat C of the pulp was measured according to JIS K7123. The density ρ of the pulp was measured according to the JIS K2151 6 bulk density test method.

<General bacterial count test method>
The number of general bacteria was measured according to JIS K0101, and was counted as the number of bacteria in 1 g of feed pellet sample.
Furthermore, 500 g of the pellets immediately after production obtained in Examples and Comparative Examples were separated into 1-L screw-mouth glass bottles, capped, and allowed to stand at 30 ° C. for 90 days, and then each sample was subjected to the above general bacterial count test. Provided.

  From Table 2, it can be seen that in the feed pellets of Examples 1 to 3, the increase in the number of bacteria was suppressed, and decay over time was suppressed. On the other hand, it can be seen that in Comparative Example 1 in which the sterilization process was insufficient and in Comparative Example 3 in which the sterilization process was not performed, bacteria were observed and increased over time. Moreover, the comparative example 2 exposed to the excessive temperature at the sterilization process has impaired the external appearance by scorching.

<Salary test (in situ digestion test)>
Digestibility in the lumen was measured by the in situ method (Journal of Dairy Science, vol. 71, pages 2051-2069, 1988, James E. Nocek).
A polyester bag (# R1020, polyester, 10 cm × 20 cm, average pore diameter of 50 ± 15 μm, ANKOM Technology Corp., Fairport, NY, USA) weighing 5 g (air dry weight) of sample in the lumen of the test animal (cow) I put it in. At the time of 2 hours, 4 hours, 8 hours, 24 hours, 48 hours, 72 hours, 96 hours after charging, the polyester bag is taken out from the lumen, washed with water, and the dry matter constant weight is determined at 60 ° C. Calculated. Moreover, the polyester bag containing the feed which was not put into the lumen but was simply washed with water was used as a sample having a decomposition time of 0 hour.
Each sample was measured in triplicate with different implementation dates. Table 3 shows the test results of elapsed time and digestibility.

  From Table 3, although the digestion rate of the feed pellets of Examples 1 to 4 was lower than that of Comparative Examples 4 and 5, it showed a high digestibility after 48 hours. Therefore, although the final digestibility is higher than that of concentrated feed and grass, the digestion rate is slow, so it seems to be effective in preventing rumen acidosis.

Claims (5)

In the production of ruminant feed pellets containing kraft pulp,
a) pelletizing kraft pulp;
b) The sterilization process which heat-processes the pelletized kraft pulp in the range whose temperature increase rate s represented by following formula 1 is 5 degrees C / sec or more and 200 degrees C / sec or less,
A method for producing ruminant feed pellets.
s (° C./sec.)=ΔT/t (Formula 1)
(ΔT is the rising temperature of the kraft pulp, and t is the residence time in the die hole.)   The method for producing ruminant feed pellets according to claim 1, wherein the step of pelletizing the kraft pulp and the sterilization step of heat-treating the pelletized kraft pulp are performed simultaneously.   The method for producing ruminant feed pellets according to claim 1 or 2, wherein the pellet has a length of 1 to 200 mm.   The manufacturing method of the feed pellet for slaughter animals in any one of Claims 1-3 whose diameter of a pellet is 3-10 mm.   The method for producing feed pellets for mammals according to any one of claims 1 to 4, wherein the moisture content of kraft pulp before pelletization is dehydrated to 35% by mass or less.