Pulverulent compositions of a complex between an acid and a metal and method of preparation thereof

Abstract

Pulverulent compositions of a complex between an acid and a metal form an at least partially spherical particle. The acid is selected from 2-hydroxy-4-methyl-thiobutanoic acid (HMTBA), methionine, aspartic acid, the alginic acids, the pectinic acids, and the corresponding anions, in particular 2-hydroxy-4-methyl-thiobutanoate, methioninate, aspartate, the alginates and the pectinates. The metal is divalent or trivalent. The particle has an amorphous fraction the mass of which represents at least 50% of the total mass of the particle. The particle is substantially devoid of uncomplexed acid or anion and of uncomplexed metal or metal cation.

Claims

1. A spray-dried particle, comprising: a spray-dried homogeneous sphere or a fraction of a spray-dried homogeneous sphere, being formed of a complex or a salt, between an acid or a corresponding anion and at least one metal or a corresponding metal cation, said acid or corresponding anion being selected from the group consisting of 2-hydroxy-4-methyl-thiobutanoic acid (HMTBA), methionine, aspartic acid, alginic acids, pectinic acids, corresponding anions, 2-hydroxy-4-methyl-thiobutanoate, methioninate, aspartate, alginates and pectinates, said metal or metal cation being divalent or trivalent, said spray-dried particle having an amorphous fraction a mass of which represents at least 50% of a total mass of said spray-dried particle, said spray-dried particle being substantially devoid of uncomplexed acid or anion and of uncomplexed metal or metal cation.

2. The spray-dried particle according to claim 1, wherein a ratio of at least one of a mass of uncomplexed acid or anion or of said at least one uncomplexed metal or cation to the total mass of said spray-dried particle is below 20%.

3. The spray-dried particle according to claim 2, wherein said complex has the following formula (Ia):
(Acid).sub.nM  (Ia) where M represents said metal, n being equal to 2 when said metal is divalent and to 3 when said metal is trivalent, said complex being a salt of formula (HMTBA).sub.2Ca, (HMTBA).sub.2Mg, (HMTBA).sub.2Fe, (HMTBA).sub.2Mn, (HMTBA).sub.2Zn, (HMTBA).sub.2Cu, (HMTBA).sub.3Fe, (HMTBA).sub.3Al, (methionine).sub.2Ca, (methionine).sub.2Mg, (methionine).sub.2Cu, (methionine).sub.3Fe, (methionine).sub.3Al, (aspartic acid).sub.2Ca, (aspartic acid).sub.2Mg, (aspartic acid).sub.2Fe, (aspartic acid).sub.2Mn, (aspartic acid).sub.2Zn, (aspartic acid).sub.2Cu, (aspartic acid).sub.3Fe, or (aspartic acid).sub.3Al.

4. The spray-dried particle according to claim 2, wherein the ratio is below 5%.

5. The spray-dried particle according to claim 1, wherein said complex has the following formula (Ia):
(Acid).sub.nM  (Ia) where M represents said metal, n being equal to 2 when said metal is divalent and to 3 when said metal is trivalent, said complex being a salt of formula (HMTBA).sub.2Ca, (HMTBA).sub.2Mg, (HMTBA).sub.2Fe, (HMTBA).sub.2Mn, (HMTBA).sub.2Zn, (HMTBA).sub.2Cu, (HMTBA).sub.3Fe, (HMTBA).sub.3A1, (methionine).sub.2Ca, (methionine).sub.2Mg, (methionine).sub.2Fe, (methionine).sub.2Mn, (methionine).sub.2Zn, (methionine).sub.2Cu, (methionine).sub.3Fe, (methionine).sub.3Al, (aspartic acid).sub.2Ca, (aspartic acid).sub.2Mg, (aspartic acid).sub.2Fe, (aspartic acid).sub.2Mn, (aspartic acid).sub.2Zn, (aspartic acid).sub.2Cu, (aspartic acid).sub.3Fe, or (aspartic acid).sub.3Al.

6. The spray-dried particle according to claim 1, wherein said metal or corresponding cation is selected from the group consisting of Mg, Be, Ca, Sr, Ba, Mn, Fe, Co, Ni, Cu, Zn, Pt, B, Al, Ga, and In.

7. The spray-dried particle according to claim 1, wherein said anion being 2-hydroxy-4-methyl-thiobutanoate and said cation being Ca.sup.2+, or said anion being methioninate or 2-hydroxy-4-methyl-thiobutanoate and said cation being selected from the group consisting of Mg.sup.2+, Ca.sup.2+, Fe.sup.2+, Fe.sup.2+, Zn.sup.2+, Mn.sup.2+ and Cu.sup.2.

8. A pulverulent composition of more than one spray-dried particle as defined in claim 1, wherein at least one of a granulometric size of said more than one spray-dried particle being in a range from 10 to 3000 μm in granulometric average [Dv(0.5)], or said composition having a flowability index that is in the range from 4 to 18 [Flodex index], or said composition being such that, for a substantial portion of said composition, a spray dried particle of said portion is agglomerated with at least one other spray-dried particle of said portion.

9. A method for preparing a pulverulent composition of more than one spray-dried particle according to claim 1, said method comprising: a contacting step, during which said acid is brought into contact with a mineral source of said metal or corresponding cation in a spray-drying tower in order to obtain said complex or said salt, and initiate precipitation, a spraying step, during which precipitation of said complex or said salt takes place and an ensemble of sprayed particles is formed, and a spray-drying step, during which precipitation of said complex or said salt of said ensemble of sprayed particles proceeds until there is complete solidification of the spray-dried particles, thereby forming a stable pulverulent composition of more than one spray-dried particle.

10. The method according to claim 9, wherein the contacting and spraying steps are carried out using a device comprising a rotating spraying element, contacting being followed immediately by spraying.

11. The method according to claim 9, further comprising: a recovering step, during which the stable pulverulent composition of more than one spray-dried particle is collected, wherein the contacting step and the spraying step are performed in a spray-drying tower using a spraying device comprising a rotating spraying element, and said spraying step immediately following said contacting step.

12. The method according to claim 9, wherein: said contacting step is carried out by at least one of: mixing an aqueous medium containing said acid, and an aqueous medium containing said metal or cation, and continuous contacting of said acid with the mineral source of said metal or corresponding cation, said continuous contacting being carried out in a device selected from the group consisting of static or dynamic mixers, kneaders, extruders, mixers without an internal component and ultrasonic mixers.

13. The method according to claim 9, wherein said complex is of the following formula (Ia):
(Acid).sub.nM  (Ia) where M represents said metal, said complex being a salt of formula (HMTBA).sub.2Ca, (HMTBA).sub.2Mg, (HMTBA).sub.2Fe, (HMTBA).sub.2Mn, (HMTBA).sub.2Zn, (HMTBA).sub.2Cu, (HMTBA).sub.3Fe, (HMTBA).sub.3Al, (methionine).sub.2Ca, (methionine).sub.2Mg, (methionine).sub.2Fe, (methionine).sub.2Mn, (methionine).sub.2Zn, (methionine).sub.2Cu, (methionine).sub.3Fe, (methionine).sub.3Al, (aspartic acid).sub.2Ca, (aspartic acid).sub.2Mg, (aspartic acid).sub.2Fe, (aspartic acid).sub.2Mn, (aspartic acid).sub.2Zn, (aspartic acid).sub.2Cu, (aspartic acid).sub.3Fe, or (aspartic acid).sub.3Al.

14. The method according to claim 9, wherein said metal or corresponding cation is selected from the group consisting of Mg, Be, Ca, Sr, Ba, Mn, Fe, Co, Ni, Cu, Zn, Pt, B, Al, Ga, and In.

15. The method according to claim 9, wherein said anion being 2-hydroxy-4-methyl-thiobutanoate and said cation being Ca.sup.2+, the source of Ca.sup.2+ being selected from the group consisting of lime, milk of lime, slaked lime, calcium hydrogen carbonate, calcium carbonate and Ca(OH).sub.2, or said anion being methioninate or 2-hydroxy-4-methyl-thiobutanoate and said cation being selected from the group consisting of Mg.sup.2+, Ca.sup.2+, Fe.sup.2+, Fe.sup.2+, Zn.sup.2+, Mn.sup.2+ and Cu.sup.2+, a source of said cation being selected from oxide, hydroxide, an aqueous solution of hydroxide or a carbonate of said cation.

16. The method according to claim 9, comprising an additional step of agglomeration in a spray-drying tower which is a multiple effect spray-drying tower, and reacting said acid with said mineral metal source including agglomeration.

17. The spray-dried particle according to claim 1, wherein the amorphous fraction mass is at least 70% of the total mass of said spray-dried particle.

18. The spray-dried particle according to claim 1, wherein the amorphous fraction mass is at least 90% of the total mass of said spray-dried particle.

Description

DESCRIPTION OF THE FIGURES

(1) FIG. 1 is a schematic diagram of a method according to the invention, carried out in a multiple effect tower.

(2) An aqueous medium containing an acid, represented by circle A, optionally passes through a heater 130 and feeds, by a pump 131, the contacting device 134. An aqueous medium containing a metal or metal cation represented by circle B optionally passes through a heater 132 and feeds, by a pump 133, the contacting device 134. The aqueous phase resulting from mixing aqueous medium A with aqueous medium B is sprayed in the spray tower via spraying device 104 intended for the production of monodisperse or polydisperse aerosols.

(3) Circle C represents an additional spraying device for anti-agglomerating agent via a powder metering device 136, if necessary.

(4) Circle D represents introduction of the hot carrier gas in the spray-drying version, via fan 124.

(5) Circle E represents introduction of the secondary carrier gas, for drying and/or final cooling of the stabilized final composition obtained, solid or undergoing solidification, via a fan 137.

(6) A cyclone 138 separates some or all of the end product F, i.e. the pulverulent composition, which is recovered, and the carrier gas G, which is discharged.

(7) An external vibrated fluidized bed 139 may also be provided for recovering some or all of the end product H, i.e. the pulverulent composition, from the bottom of the tower.

(8) Secondary air E is introduced through a permeable bottom 142 of tower 135 to bring the pulverulent material into the form of a fluidized bed. The used air is discharged via an orifice 143 provided, through the top wall of vessel 101. In this example, the used air then passes through cyclone 138, which produces on the one hand particles of product F and on the other hand air to be discharged G. Most of the particles are collected just above the permeable wall 142. FIG. 1 shows that the particles are collected either directly at F, or via the external fluidized bed 139 at H when one is provided.

(9) Moreover, it is also possible to provide the addition, represented by circle I, in the spraying zone, of a substance in powder form, in particular fine particles of the pulverulent composition recovered at the outlet of cyclone 138, product F, or from the installation, injected by means of device 141 mainly consisting of a powder metering device.

(10) FIG. 2 is a graph showing the precipitation time (in minutes) of a mixture of milk of lime and HMTBA, as a function of the total dry extract of said mixture (as a percentage).

(11) FIG. 3 is a graph relating to sample “R”, showing the heat flow as a function of temperature, measured by differential scanning calorimetry (DSC) in isothermal mode.

(12) A melting peak is noted at 103° C. when the temperature rises, and a crystallization peak at 92° C. (start of the peak at 102° C.) when the temperature falls.

(13) FIG. 4 is a graph relating to sample “T7”, representing heat flow as a function of temperature, measured by differential scanning calorimetry (DSC) in isothermal mode.

(14) An endothermic peak of very small amplitude is noted at 82° C. when the temperature rises, followed by an extended endothermic region that is not characteristic of fusion peaks. No thermal effect is observed when the temperature falls, therefore there is absence of recrystallization of the product.

(15) FIG. 5a shows the 2D diffraction pattern obtained for sample “T7”.

(16) FIG. 5b shows the powder pattern obtained for sample “T7”.

(17) FIG. 6a shows the 2D diffraction pattern obtained for sample “R”.

(18) FIG. 6b shows the powder pattern obtained for sample “R”.

(19) Samples T7 and R were analysed by X-ray diffraction using a Bruker APEX-II Quasar diffractometer equipped with a molybdenum microsource (λ=0.71073 {acute over (Å)}).

(20) Each sample was ground beforehand in a mortar for two minutes.

(21) Each of the powders thus obtained is then transferred to a capillary with diameter of 0.5 mm that is transparent to X-rays, and is then mounted on a goniometer.

(22) The recording characteristics are perfectly identical for each sample, namely:

(23) distance from the detector: 80 mm

(24) recording time: 999 s

(25) uniform rotation of the sample about the Phi axis of 359° during acquisition

(26) position of the angles Chi, Kappa and Omega=0°

(27) recording temperature 280 K

(28) The 2D diffraction patterns obtained for each of the samples correspond to FIGS. 5a and 6a.

(29) Angular grouping of these two-dimensional images was then performed using XRD2DScan 4.1.1 software, after subtracting from each image that of the background noise recorded under the same conditions, to obtain the curves shown in FIGS. 5b and 6b.

(30) The invention is illustrated by examples 1 to 9 given below.

EXAMPLES

Example 1: Preparation of the Salt (HMTBA)2Ca

(31) Milk of lime prepared at 30% dry matter is mixed continuously in a pipeline containing a static mixer with a solution of HMTBA at 88% dry matter in the ratio 22.2% of lime (calculation based on the dry matter used) and 77.8% of HMTBA (calculation based on the dry matter used).

(32) The contacting time is 7 seconds.

(33) The reaction medium is then sprayed using a nozzle according to the knowledge of a person skilled in the art, in a single effect spray tower with an inlet temperature of 140° C. and an outlet temperature of 79° C.

(34) The product is then processed in a fluidized air bed dryer to obtain an agglomerated powder to simulate a multiple effect spray tower.

(35) The product obtained has a content of HMTBA of 81.4%, of Ca.sup.2+ 11.8%, and a water content of 1.3%. The average granulometry is 240 μm and the density is 300 g/L.

Example 2: Another Preparation of the Salt (HMTBA)2Ca

(36) Milk of lime prepared at 30% dry matter is mixed continuously in a pipeline containing a static mixer at 138 kg/h with a solution of HMTBA at 88% dry matter at 154 kg/h to give a reaction medium of 60% dry matter.

(37) The contacting time is 15 seconds.

(38) The reaction medium is sprayed using a nozzle according to the knowledge of a person skilled in the art, in a single effect spray tower with an inlet temperature of 185° C. and an outlet temperature of 128° C.

(39) The product obtained contains 84.9% of HMTBA, 12.0% of Ca.sup.2+ and 0.5% of water.

(40) The average granulometry is 156 μm (Dv(0.5) in laser granulometry), and the density is 170 g/l.

Example 3: Preparation of a Mg Salt of HMTBA

(41) A suspension of magnesium hydroxide at 20% dry matter is mixed continuously in a pipeline containing a static mixer at 2.9 kg/h, with a solution of HMTBA at 70% dry matter at 4.3 kg/h.

(42) The contacting time during reactive spraying is 7 seconds.

(43) The reaction medium is then sprayed using a nozzle according to the knowledge of a person skilled in the art in a single effect spray tower with an inlet temperature of 140° C. and an outlet temperature of 76° C.

(44) The product obtained has a content of HMTBA of 91.2%, a content of Mg.sup.2+ of 7.4% and a water content of 1.4%.

(45) The average granulometry is 7 μm and the density is 310 g/L.

Example 4: Preparation of a Li Salt of HMTBA

(46) Milk of lithium hydroxide prepared at 10% dry matter is mixed continuously in a pipeline containing a static mixer at 3.6 kg/h with a solution of HMTBA at 70% dry matter at 4.0 kg/h.

(47) The contacting time is 7 seconds.

(48) The reaction medium is then sprayed using a nozzle according to the knowledge of a person skilled in the art in a spray tower with an inlet temperature of 160° C. and an outlet temperature of 70° C.

(49) The product obtained contains 89.2% of HMTBA, 4.2% of Li.sup.+ and 6.6% of water.

(50) The average granulometry is 5 μm, and the density is 360 g/L.

Example 5: Preparation of the Salt (HMTBA)2Ca Using an Atomizing Turbine

(51) Milk of lime prepared at 20% dry matter is mixed continuously in an atomizing turbine (of the NIRO Atomizer type) at 3.9 kg/h with a solution of HMTBA at 70% dry matter at 3.4 kg/h.

(52) The contacting time is 120 milliseconds.

(53) The product is then atomized in a single effect spray tower with an inlet temperature of 140° C. and an outlet temperature of 90° C.

(54) The product obtained has a content of HMTBA of 85.0%, of Ca.sup.2+ 10.7%, and a water content of 1.3%.

(55) The average granulometry is 43 μm and the density is 380 g/L.

Example 6: Preparation of a Methionine Salt

(56) Milk of lime prepared at 20% dry matter is mixed continuously in a pipeline containing a static mixer with a solution of methionine at 20% dry matter.

(57) The contacting time is 7 seconds. The flow rate of the milk of lime is 1.5 kg/h and that of the methionine solution is 6.0 kg/h.

(58) The reaction medium is then sprayed using a nozzle according to the knowledge of a person skilled in the art in a single effect spray tower with an inlet temperature of 160° C. and an outlet temperature of 75° C.

(59) The product obtained has a content of HMTBA of 86.9%, of Ca.sup.2+ 11.7%, and a water content of 1.3%.

(60) The average granulometry is 35 μm and the density is 300 g/L.

Example 7: Preparation of a Salt (HMTBA)2Ca by a Method Not According to the Present Invention, and Comparison of the Product Obtained with a Product According to the Invention

(61) An HMTBA salt is prepared by addition, in a vessel, of 100 g of HMTBA at 88% dry matter, and 88 g of milk of lime containing 25% dry matter.

(62) Mixing is carried out by stirring with a propeller mixer for 20 seconds.

(63) The mixture obtained is left to crystallize for 20 h at ambient temperature and then dried in a stove at 105° C. for 24 h.

(64) The product “R” thus obtained is ground in a mortar.

(65) The conditions for production of sample “R” make it possible to obtain a crystallized HMTBA salt.

(66) This product “R” as well as an HMTBA salt obtained under the conditions for carrying out example 2 called “T7” are analysed by X-ray diffraction and by differential scanning calorimetry (DSC) in isothermal mode.

(67) FIG. 3 obtained by DSC shows that sample R has a low-energy endothermic peak when the temperature rises as well as an exothermic peak when the temperature falls. These two peaks reflect respectively the melting of crystals and then the recrystallization of these crystals during cooling.

(68) A second temperature cycle gives the same endo- and exothermic effects, confirming that it is indeed a reversible phenomenon of melting and crystallization. No other thermal effects are seen during these temperature cycles.

(69) It is deduced from this that compound “R” is a 100% crystalline compound.

(70) For the compound of the invention analysed by DSC, FIG. 4 shows that an endothermic peak of very small amplitude is observed at 82.39° C., which might correspond to a glass transition phenomenon (typical of amorphous systems) followed by extended endothermic effects not characteristic of fusion peaks. No thermal effect is observed when the temperature falls, therefore there is no recrystallization of the product after the 1st temperature rise.

(71) It may be concluded that in contrast to sample “R”, the sample of the invention is in mainly amorphous form.

(72) These same samples were analysed by X-ray diffraction.

(73) FIGS. 5b and 6b show that the first peak is much wider for sample T7 than for sample “R”. This indicates that there is short-range order but not long-range order as suggested by the absence of subsequent peaks (in particular those at 5° and 9.2°). This indicates a completely amorphous sample, with only short-range order. The degree of crystallinity would then be close to 0%.

Example 8: Another Preparation of the Salt (HMTBA)2Ca

(74) Milk of lime prepared at 26.2% dry matter is mixed continuously by means of an ultrasonic mixing device at 126 kg/h with a solution of HMTBA at 88% dry matter at 143 kg/h to give a reaction medium with 59% dry matter.

(75) The contacting time is 20 seconds.

(76) The reaction medium is sprayed using a nozzle according to the knowledge of a person skilled in the art, in a single effect spray tower with an inlet temperature of 200° C. and an outlet temperature of 136° C.

(77) The product obtained contains 83.5% of HMTBA, 12.3% of Ca.sup.2+ and 2.7% of water.

Example 9: Another Preparation of the Salt (HMTBA)2Ca

(78) Milk of lime prepared at 45% dry matter is mixed continuously in a pipeline containing a static mixer with a solution of HMTBA at 88% dry matter in the ratio 20% of lime (calculation based on the dry matter used) and 80% of HMTBA (calculation based on the dry matter used).

(79) The contacting time is 7 seconds.

(80) The reaction medium is then sprayed using a nozzle according to the knowledge of a person skilled in the art, in a single effect spray tower with an inlet temperature of 160° C. and an outlet temperature of 90° C.

(81) The product obtained has a content of HMTBA of 85.3%, of Ca.sup.2+ 11.1%, and a water content of 1.7%. The average granulometry is 40 μm and the density is 380 g/L.

Example 10: Preparation of a Sodium Salt of Aspartic Acid

(82) A solution of sodium hydroxide at 50% concentration by weight is mixed continuously in a pipeline containing a static mixer at 1.4 kg/h with a suspension of aspartic acid at 20% concentration by weight at 11.6 kg/h.

(83) The contacting time is 15 seconds. The product is then atomized in a single effect spray tower with an inlet temperature of 180° C. and an outlet temperature of 95° C.

(84) The product obtained is a stable, flowable white powder, with good solubility in water. The average granulometry is 55 μm, the water content is 2.3% and the solution pH is 6.5.

Example 11: Preparation of a Calcium Salt of Aspartic Acid

(85) Milk of lime prepared at 30% dry matter is mixed continuously in a pipeline containing a static mixer at 1.9 kg/h with a suspension of aspartic acid at 20% concentration by weight at 10.4 kg/h.

(86) The contacting time is 15 seconds. The product is then atomized in a single effect spray tower with an inlet temperature of 180° C. and an outlet temperature of 90° C.

(87) The product obtained is a stable, flowable white powder, with good solubility in water. The average granulometry is 35 μm, the water content is 2.9% and the solution pH is 6.8.

Example 12: Preparation of a Salt of (HMTBA) of Type 4

(88) Milk of lime prepared at 30% dry matter is mixed continuously in a pipeline containing a static mixer at 70 kg/h with a solution of HMTBA at 88% dry matter at 193 kg/h.

(89) The contacting time is 15 seconds. The product is then atomized in a multiple effect spray tower with an inlet temperature of 180° C., an outlet temperature of 95° C., and recycling of fine particles to the spraying zone.

(90) The product obtained has a content of 91.6% HMTBA, 5.7% calcium, and a water content of 1.5%.

Example 13: Preparation of a Cu Salt of HMTBA

(91) A suspension of copper hydroxide at 35% dry matter is mixed continuously in a pipeline containing a static mixer at 2.8 kg/h, with a solution of HMTBA at 88% dry matter at 3.5 kg/h.

(92) The contacting time during reactive spraying is 8 seconds.

(93) The reaction medium is then sprayed using a nozzle according to the knowledge of a person skilled in the art in a single effect spray tower with an inlet temperature of 140° C. and an outlet temperature of 80° C.

(94) The product obtained has a content of HMTBA of 81.8%, a content of Cu.sup.2| of 15.4% and a water content of 1.2%.

(95) The average granulometry is 40 μm and the density is 420 g/L.

Example 14: Use of a (HMTBA)2Ca Salt According to the Invention for Feeding Laying Hens

(96) Summary

(97) Laying hens were fed either with DL-methionine (DLM), or with an HMTBA-Ca salt according to the invention, or with a combination (50/50) of the two for 6 weeks. The laying performance and the parameters relating to the eggs were measured throughout the 6 weeks.

(98) HMTBA-Ca is as effective as DLM for most of the parameters, but improves laying efficiency (consumption index or average weight of the eggs). HMTBA-Ca helps to obtain a higher weight of albumin than that obtained with DLM.

(99) The combination of HMTBA-Ca and DLM gives intermediate results for the performance parameters or the parameters relating to the eggs.

(100) Experimental Conditions

(101) Eighty laying hens aged 45 weeks were housed for 6 weeks and were distributed at random into three equal groups (20 per group). Each hen was kept in an individual cage at a temperature of (20±2° C.) with controlled lighting conditions. All the hens were offered a similar basic diet, with or without addition of DLM, of HMTBA-Ca or of a 50/50 mixture (HMTBA-Ca: DLM) (Tables 1 and 2) to give a supplement in methionine equivalent of 0.13% for all the food compositions. All the laying hens had free access to drinking water and were fed throughout the 6-week period of the experiment. The egg laying performance, including the components of the eggs, was measured throughout the 6-week period.

(102) TABLE-US-00001 TABLE 1 Composition of the feed (%) Group 1 Group 2 Group 3 Raw material % % % Maize 50 50 50 Wheat 16.1 16.1 16.1 Soya cake 48 22.07 22.07 22.07 Soya oil 0.95 0.95 0.95 DL-Methionine (NP99) 0.13 0 0.07 HMTBA-Ca 0 0.15 0.08 Limestone 8.12 8.12 8.12 Calcium hydrogen phosphate 1.48 1.48 1.48 Salt 0.35 0.35 0.35 Premix 0.8 0.8 0.8 Total 100 100 100 Nutrients Crude proteins (%) 16.5 16.5 16.5 Metabolizable energy (kcal/kg) 2730 2730 2730 Calcium (%) 3.508 3.508 3.508 Available phosphorus (%) 0.331 0.331 0.331 Dig. Methionine (%) 0.37 0.37 0.37 Dig. M + C (%) 0.603 0.603 0.603 Dig. Lysine (%) 0.722 0.722 0.722

(103) TABLE-US-00002 TABLE 2 Levels of methionine supplementation: expected and measured (%) Group 1 Group 2 Group 3 Total methionine (%) 0.35 0.24 0.28 Methionine added (%) 0.11 0.00 0.06 HMTBA added (%) 0.00 0.11 0.07 Total in methionine equivalent (%) 0.35 0.35 0.35
Laying Performance and Results Relating to the Characteristics of the Eggs

(104) Data relating to laying performance and the composition of the eggs (albumen and yolk) are presented in Table 3 below.

(105) The laying hens fed with the HMTBA-Ca salt produce a higher daily weight of eggs than those fed with DLM, as the average weight of the eggs with HMTBA-Ca is 2.3% higher relative to that obtained with DLM. The proportion of albumen and yolk is not significantly affected by the source of methionine, but the eggs of the hens fed with HMTBA-Ca contain more albumen (+ 3%) relative to the eggs of the hens fed with DLM.

(106) TABLE-US-00003 TABLE 3 Results relating to the different methionine supplements. Group 1 Group 2 Group 3 DLM HMTBA-Ca 50/50 mixture Standard Standard Standard ANOVA Mean error Mean error Mean error p value Initial body 1724.7 126.7 1738.6 135.6 1729.3 110.5 0.94 weight (g/hen) Daily food 112.4 8.1 112.7 5.9 113.0 5.9 0.97 intake (g/day) Laying 95% 5% 95% 4% 96% 4% 0.63 frequency (%) Average 63.4 4.0 64.9 3.6 64.1 3.1 0.47 weight of the eggs (g/egg) Weight of eggs 60.3 4.2 62.0 4.6 61.8 4.0 0.41 (g/day) Albumen 38.38 2.78 39.53 2.67 39.14 2.69 0.71 (g/egg) Yolk (g/egg) 16.38 1.08 16.47 0.95 16.18 1.07 0.74 Consumption 1.87 0.12 1.82 0.12 1.83 0.10 0.44 index (g feed/g egg) Final body 1834.9 98.0 1897.2 150.0 1850.2 112.8 0.28 weight (g/hen)

Example 15: Use of a (HMTBA)2Ca Salt According to the Invention for Feeding Growing Chickens

(107) Summary

(108) Growing chickens were supplemented (0.3%) either with DLM, or with HMTBA or with HMTBA-Ca salt according to the invention, for 46 days. HMTBA and more particularly HMTBA-Ca showed the best growth performance. Moreover, HMTBA-Ca showed far better digestibility of the nutrients than that obtained with the other two forms of methionine.

(109) Experimental Conditions

(110) One hundred and forty-seven commercial chickens (1 day old, 48 g) were housed from day 1 to day 46, including the starting phase (days 1-21) and the finishing phase (days 22-46). All the chickens were randomly distributed in seven equal groups (21 per group), and each group was made up of three subgroups of 7 birds each. Each subgroup was kept in an enclosure at a temperature of (28±2° C.), with controlled lighting conditions. All the chickens were offered a similar basic diet, with or without addition of DLM, HMTBA or HMTBA-Ca at levels of 0 (control) or 0.3% in the starting phase and 0 or 0.24% in the finishing phase (Table 4). All the chickens had free access to food and drinking water throughout the test period of 46 days. The weight of the chickens was measured every week and food intake was monitored throughout the experiment.

(111) The excrement of the chickens was collected for the 3 days following the 42.sup.nd day of the experiment, were frozen and stored (at −20° C.) for later chemical analyses.

(112) At the end of the experiment, the birds were weighed individually and sacrificed. The abdominal fat, the muscles of the thigh and of the breast were taken, lyophilized and weighed.

(113) TABLE-US-00004 TABLE 4 Composition of the feed Starting phase Finishing phase Composition (%) (days 0-21) (days 21-46) Maize 50.42 49.72 Soya cake 37.00 32.00 Wheat 4.00 8.00 NaCl 0.34 0.34 Calcium hydrogen phosphate 1.90 1.50 Limestone 1.00 1.10 Choline 0.04 0.04 Oil 5.00 7.00 Sources of methionine.sup.1 0-0.30 0-0.24 Premix, vitamins-minerals.sup.2 0.30 0.30 Composition of nutrients ME, Mcal/kg 3.04 3.18 CP, % 20.97 19.27 Lys, % 1.12 1.10 Met + cysteine, % 0.67 0.63 Met 0.33 0.31 P available, % 0.44 0.37 Ca, % 0.97 19.27 P total, % 0.69 0.61 .sup.1HMTBA, DLM or HMTBA-Ca .sup.2per kg of feed: vitamin A (retinol acetate), 1500 IU; cholecalciferol, 200 IU; vitamin E (DL-α-tocopherol), 10 IU; riboflavin, 3.5 mg, pantothenic acid, 10 mg; niacin, 30 mg; cobalamin, 10 g, choline chloride, 1000 mg; biotin, 0.15 mg, folic acid, 0.5 mg, thiamine, 1.5 mg; pyridoxine, 3.0 mg, Fe, 80 mg; Zn, 40 mg, Mn, 60 mg, I, 0.18 mg; Cu, 8 mg; Se, 0.15 mg.
Results
Performance Relating to Growth and Composition of the Carcasses

(114) Data relating to the growth performance and composition of the carcasses are summarized in Tables 5 and 6. The final body weight and the gain in body weight are significantly higher in the chickens fed with HMTBA 0.3% relative to the control group. There is no significant difference in food supply for the seven groups, but a lower consumption index was observed in the HMTBA 0.3% group. In the course of the experiment, the weight of the muscles of the thigh and breast of the chickens fed with HMTBA or HMTBA-Ca was significantly higher than those fed with DLM. No significant difference was observed for the weight of the abdominal fat as a function of the source of methionine, apart from an increase in the percentage of abdominal fat in the group supplemented with HMTBA-Ca (0.3%).

(115) TABLE-US-00005 TABLE 5 Results relating to supplementation with DLM, HMTBA or HMTBA-Ca for 46-day-old chickens*. Final body weight Gain in body weight Food intake Feeding:gain Group (kg/chicken) (g/chicken/day) (g/chicken/day) (g:g) Control 3.05 ± 0.10.sup.a  67.85 ± 2.26.sup.a  134.85 ± 3.72 1.99 ± 0.01 0.3% DLM 3.17 ± 0.15.sup.ab 70.47 ± 3.37.sup.ab 141.51 ± 0.24 2.01 ± 0.10 0.3% HMTBA 3.44 ± 0.02.sup.b  76.41 ± 0.40.sup.b  142.23 ± 8.46 1.86 ± 0.12 0.3% HMTBA-Ca 3.38 ± 0.28.sup.ab 75.08 ± 6.18.sup.ab  144.53 ± 20.93 1.91 ± 0.12 *The values are expressed as mean ± standard deviation. Each group represents 21 chickens at age 46 days. .sup.a,b,cWithin one and the same column, the values with different superscripts are significantly different (P < 0.05).

(116) TABLE-US-00006 TABLE 6 Effect of DLM, HMTBA or HMTBA-Ca on the composition of the carcass of the 46-day chickens*. DL PDL DB PDB PDAT Group (g) (%) (g) (%) (%) Control 549.42 ± 15.32.sup.a  .sup. 20.31 ± 0.16.sup.ab 521.69 ± 64.00.sup.a  20.88 ± 1.63.sup.ab 1.77 ± 0.62.sup.a 0.3% DLM 586.03 ± 23.43.sup.ab 20.12 ± 0.22.sup.a .sup. 596.88 ± 56.68.sup.abc 22.77 ± 1.44.sup.b 1.88 ± 0.43.sup.a 0.3% HMTBA 648.98 ± 27.92.sup.c  21.98 ± 0.97.sup.c 669.66 ± 50.16.sup.c 22.77 ± 1.44.sup.b .sup. 2.07 ± 0.63.sup.ab 0.3% HMTBA-Ca 588.64 ± 38.07.sup.ab 22.06 ± 1.64.sup.c .sup. 617.54 ± 45.21.sup.bc 22.98 ± 3.00.sup.b 2.49 ± 0.59.sup.b DL, weight of the muscles of the thigh DB, weight of the muscles of the breast PDL, ratio of the weight of the muscles of the thigh (without bone or skin) to that of the eviscerated chicken PDB, ratio of the weight of the muscles of the breast (without bone or skin) to that of the eviscerated chicken PDAT, ratio of the weight of the abdominal fat to that of the eviscerated chicken *The values are expressed as mean ± standard deviation. Each group represents 21 chickens at age 46 days. .sup.a,b,cWithin one and the same column, the values with different superscripts are significantly different (P < 0.05).
Apparent Digestibility

(117) As shown in Table 7, the diets supplemented with methionine equivalent led to a significant increase in apparent digestibility of the dry matter, of the crude proteins and crude fats in the chickens, in the order HMTBA-Ca>HMTBA>DLM. However, the apparent digestibility of ash was significantly lower than for the control groups. The diets containing HMTBA-Ca or HMTBA gave improvements in apparent digestibility relative to diets containing DLM, this being mainly due to the overall higher activity of the digestive enzymes in the duodenum and the jejunum.

(118) TABLE-US-00007 TABLE 7 Apparent digestibility (%) of dry matter, crude proteins, crude fats and ash, in 46-day chickens supplemented with DLM, HMTBA or HMTBA-Ca*. Group dry matter crude proteins crude fats Ash Control 68.39 ± 1.31.sup.a 44.23 ± 2.95.sup.a  81.93 ± 1.90.sup.a 86.03 ± 3.98.sup.d 0.3% DLM 78.22 ± 1.70.sup.c 63.70 ± 2.85.sup.cd 86.15 ± 0.93  56.02 ± 1.01.sup.b 0.3% HMTBA .sup. 79.02 ± 1.61.sup.cd 62.40 ± 2.89.sup.cd .sup. 87.80 ± 1.39.sup.bc 55.83 ± 0.16.sup.b 0.3% HMTBA-Ca 81.80 ± 0.32.sup.d 66.44 ± 0.37.sup.cd 90.28 ± 0.20.sup.c 44.62 ± 0.89.sup.a *The values are expressed as mean ± standard deviation for 10 chickens. .sup.a,b,cWithin one and the same column, the values with different superscripts are significantly different (P < 0.05).

CONCLUSION

(119) The present study shows that diets comprising HMTBA-Ca or HMTBA lead to improvement in growth and in the composition of the carcass relative to diets containing DLM. The diet supplemented with HMTBA-Ca (0.3%) led to the highest weight of muscles of the thigh and breast, relative to the other groups. Moreover, the diet supplemented with HMTBA-Ca led to a greater apparent digestibility relative to the group supplemented with DLM. The results show that supplementation with HMTBA or HMTBA-Ca led to an increase in the gain in body weight, and in the weight of the muscles of the thigh and breast in the absence of any reduction in food intake by induction of the activity of the digestive enzymes and by regulation of intestinal absorption of essential nutrients.