IE54869B1 - Products based on complexes of urea and of materials containing hydrolyzed lactose, their preparation and their use for feeding ruminants - Google Patents

Abstract

1. Products for feeding ruminants characterized in that they are formed by reaction of urea with a lactose-containing material the lactose of which has previously been at least partially hydrolyzed to glucose and galactose, and in that they contain less than 2% by weight of free urea. [EP0113288A1]

Description

-1a- The invention relates to products based on complexes of urea and of materials containing hydrolyzed lactose, their preparation and their use for feeding ruminants.

It is well known to incorporate urea in feeds for 5 ruminants; the quantity of urea which can be incorporated is, however, limited to a few percent because urea decomposes in the rumen of the animal, giving ammonia which is toxic to the latter.

To counteract this disadvantage, it has been proposed to 10 replace free urea with certain sugar-urea complexes, generally called glycosyl ureas, in order, in particular, to avoid appreciable decomposition of urea to ammonia in the rumen. Lactosyl ureas (complexes of lactose and urea) (see U.S. Patent No. 4,267,314), in particular, 15 have thus been proposed. These products have not, however, been employed in practice for economic reasons. FR-A-2,249,623 relates to feeds for ruminants by reacting a non-protein nitrogenous compounds such as urea with at least one carbohydrate, which may have been previously 20 hydrolyzed under acid conditions. Said feeds are mainly formed by the Maillard reaction.

US-A-2,612,497 describes a process for the preparation of ureides of hexoses by condensing the urea with a hexose or a polysaccharide forming hexoses under reaction 25 conditions by heating in the presence of water and dehydrating agent such as sulphuric or phosphoric acid.

Chemical Abstracts, vol 98,pp 718\9, abstract 54365 describes the synthesis of glycosylureas and galactosylureas -1b- by reacting lactose and urea, then acid hydrolysis of the resulting product.

None of the documents suggest using as the starting material a lactose-containing material previously hydrolyzed to glucose and galactose, or that the use of such a starting material could lead to an end product with a low free urea content.

The invention aims at providing new products based on complexes of urea, suitable for feeding ruminants, which offer the advantages of a high possible urea content and of allowing only a low proportion of free urea to remain.

The invention relates to new complex products formed from urea and a lactose-containing material wherein the lactose is at least partially hydrolyzed to glucose and galactose.

According to the invention there is provided a product for feeding ruminants which is formed by reaction of urea with a lactose-containing material the lactose of which has previously been at least partially hydrolyzed to glucose and galactose, and wherein the product contains less than 2% by weight of free urea.

As materials containing at least partially hydrolyzed lactose it is possible to employ permeates of lactoserums or lactose-containing liguors (obtained by deproteination of lactoserums) whose lactose has been at least partially hydrolyzed, as well as the lactoserums whose lactose has been at least partially hydrolyzed. At present, the permeates or the lactose-containing liquors with at least partially hydrolyzed lactose are preferred for economic reasons. The materials containing hydrolyzed lactose may or may not be demineralized. It is preferred nowadays to employ non-demineralized materials for economic reasons. Hydrolysis of the lactose is carried out, preferably, by an enzymatic route, known in itself, preferably with the aid of immobilized enzymes (lactase or jlrgalactosidase). This guarantees the quality of the sugars which are obtained and therefore reduces to a minimum the Mai Hard reactions and the formation of secondary products of reaction. Preferably, these new complexes contain 5 to 40 2 by weight of urea, particularly 15 to 30 2.

Preferably, the new products of the invention are employed in the form of concentrated liquid products. These products are homogeneous, stable (absence of crystallization) and easy to handle. The preferred liquid form makes it possible to save on drying and hence to minimize the costs. Nevertheless, if desired, the said products can be dried to complete dryness.

The products of the invention are easily prepared by dissolving urea in the lactose-containing material containing at least partially hydrolyzed lactose, preferably at a temperature of 5D-90°C, particularly of 60-80°C, with agitation; by adjusting, if necessary, the pH in the range from 2.5 to 4.5, preferably below 3, by adding acid to the solution obtained; and by heating the resultant acid solution at a temperature of 50-90°C, preferably 60-80°C for a time sufficient for the free urea content of the resulting product not to exceed 22 by weight, preferably 1.52 by weight. The ease of preparation appears to be attributable to an enhanced reactivity of glucose and of galactose.

According to a preferred embodiment, phosphoric acid, H3PO4, is employed to regulate the pH, the said H3PO4 being an advantageous adjuvant frequently incorporated in feeds for ruminants. The quantity of H3PO4 incorporated will usually be between 2 and 72 by weight relative to the total of the product according to the invention. The phosphoric acid can be incorporated in - 3 - the form of an equeous solution containing 85% by weight of h3po4.

The products according to the invention are feed additives which are useful for preparing feeds for ruminants, in particular in granular or liquid form. They enable, in fact, non-protein nitrogenous materials to be incorporated in the rations for ruminants.

In comparison to lactosyl-urea, they offer a higher possible content of urea, greater ease of preparation, the absence of any crystallization and, above all, an extremely reduced content of free urea.

The following non-limiting examples are given with a view to illustrating the invention.

Example 1 and comparative examples A, B and C; This example illustrates the preparation of a product according to the invention from 20% by weight of urea and a lactoserum permeate 88.52 of whose lactose has been hydrolyzed by means of immobilized β-galactosi-dase. The composition and the properties of this pei— eate containing partially hydrolyzed lactose were as fοllows: pH ............................... 3.86 color ............................ A90 IU dry extract content .............. 592 glucose .......................... 21.57% galactose ........................ 21.57% residual lactose ................. 5.62% total nitrogen matter ............ 2.00% (N x 6.38) residual true proteins ........... 0.18% ash (inorganic salts) ............ 5.10% 60 g of urea were dissolved in 300 g of hydrolyzed permeate heated at 80°C with agitation for 5 minutes. After cooling to ambient temperature, the pH was adjusted to 2.5 by adding 16.8 g of an aqueous solution containing 85% by weight H3PO4, and the whole was then heated at 80°C for 2 hours. The free urea content of the product was measured at the start, after 15 minutes and after 2 hours heating, by the urease enzyme A method.

By way of comparison, there were also prepared Ci) a product A (a urea-HjPO*, complex) by dissolving at 80°C, with agitation, ZA g of urea in 120 g of water, 5 and then adjusting the pH of the resulting solution to 2.5 by adding 1 A.5 g of a solution containing 852 HjPO^; (ii) a product B by dissolving at 80°C, with agitation, 40 g of urea in 239.5 g of an aqueous solution containing 602 by weight lactose, and then adjust-10 ino the pH of the resulting solution to 2.5 by adding 17 g of a solution containing 852 HjPO^; and liii) a product C by dissolving at 80°C, with agitation, 60 g of urea in 300 g of a non-hydrolyzed lactose liquor, then adjusting the pH to 2.5 by adding 39.1 g 15 of a solution containing 852 H3PO4.

The products A, B and C were next heated at 80°C for 2 hours, the free urea content being measured at the start, after 15 minutes and after 2 hours heating, as for the product of the invention.

The results obtained are collated in Table I be low : TABLE I A B C Example 1 Free urea t = 0 15.14 13.54 15.04 15.92 25 content, t = 15 min 9.03 10.76 10.37 1.37 2 by weight t = 2 h Free urea after 2 t/ 10.80 12.13 7.3 1.55 initial free urea, 2 Crystallization on 60-71 79-89 69-49 8.6-10 30 storage - ' abundant nil 2/3 by volume These results show the obvious superiority of the product of the invention from the points of view of the reduced free urea content and the absence of crys-35 tallization (compared to products B and C). It is also seen that the fixation of urea takes place rapidly, since less than 22 by weight of free urea remains after 15 minutes’ reaction.

Example 2: This example illustrates the preparation of products of the invention containing, respectively, 10, 20, 30 and 40 X by weight of urea. These products are prepared by an operating procedure which is similar to that followed in Example 1. The quantity of hydrolyzed permeate was 300 g. 30, 60, 90 and 120 g of urea, respectively, and 12.94, 16.80, 21.67 and 27.22 g of a solution containing 852 H3PO4, respectively, were employed.

The glucose and the free urea contents were measured at the start and after 15, 30, 45, 60 and 120 minutes' reaction at 80°C, pH: 2.5.

The results are summarized in Table II below.

It is seen that the proportion of residual free urea remains relatively constant while the proportion of incorporated urea changes from 10 to 40 2 by weight. In all the cases, it remains below 22 by weight, and even below 1.52 by weight.

Example 3: This example illustrates the influence of the pH on the solubility of sugars. Two products according to the invention are prepared, containing 202 by weight of urea, following the general operating procedure of Example 1, except for the reaction being carried out at 60°C and 16.8 g of a solution containing 852 H3PO4 being added to the first product and no H3PO4 being added to the second product. The initial pH values are 2.5 and 4.4 respectively.

The results are summarized in Table III below.

It is seen that the solubility of sugars depends on the pH. It increases with the degree of acidification. The operation will therefore be carried out, preferably, in the lower part of the pH range shown, that is to say below 3. 6 Λ si - ο 9 X o Y— O' o r- Qv O 0.91 0.93 O O' o ΙΟ UI CO ο X ιυ «) X -η. S ft) (0 L. ft) H- L rvj o • .37 in «*» ,43 07 55 UJ X 3 X m V— T— «- T“ • *» ' X Ο X CO Ό s. Ό N. 76 ...___________ CO Ν» o o o . O o o 4«» ο o ν— - V) tt) «ε Λ L· U2 4J S- X M o X 3 w Ο .16 ν έο *i- o Y·» T— v- 72 I o CO X 1 t> ft> X N- ro Ύί si si Κ» o - L·, H- ·· ftl 3 λ. t- ΚΙ c H- ΓΟ o ο 3 X .85 si CO Ό CO 87 88 4-) a X 11 ” - o o o o o • - o E 3 *P V) 10 O U1 V) ο c L. υ 3 X ft) UJ «; 0) O X *ν C ft) «ο *- o V- L. in fv- K> , 39 Ό r\j ΓΟ 09 w o o L H- 1 LU X 3 X co Y— V- 3 c o X O) c H- c c D) X o si CO si , 53 in m 57 o 4-) o 4-» X O o O o O o {_ o u ο a a o o «ε Cl. X ω X X 3 cc .90 «*· o .90 Ό CO in *λ ΚΪ t— "· ·· X CO O' O' CO CO G) CO X n X o m o in .c -c K1 si t— ru 7TABLE IX (Continued) fA O' in LA <5 O 3 O' O' O* X • • • ·· o O o o (O to o X UJ « X o in m ro LA N. L. CO fNJ f\J o < 3 • • • • UJ >0 *— *— r- cc X (V 3 w ro ΙΛ Ό d O' O' O' X • • • o o o O X O o to Φ V. A) Λ L. < 4-» H- ω CO o GC 1 3 3 3 CO LA oo *3· o t> _* «S’ Ο» Ό Ό CO 1 a> tx • • t • L·. o o O o H- X ·. e> 3 (- c H- O o N r 3 • ** sfr O 3 O' O' O' a Jl X E ·· • o o o o 3 (D V) CJ (0 c L. UJ o 3 (A ϋ O 0> X 0) 0» UJ K (Λ X Φ K) O' Ο *4- L. oo «4· «V m ο f < 3 » • • 9 3 c UJ T** «·» T*· Ψ— o cc X rsj σ> c 3 L/ Η- H- Ο o c c ο o r- in o •f- •r- cr. CO CO 00 4-» 4-» X • • u (- o o O o ο o X a a o 0 o K> u L. X X < UJ c: ·» · 3 3 CO o K) _/ h- o K) c • • • CD 3 LA rvj f\l (\J X X X .C: JZ ** o IA o LA tn T” rv 8 --- X % u o 0.91 0.91 T— O' o 0.91 0.91 c o 4-» CD c •r- E C. ID Φ *u = -° % .67 ,52 ro 'S 50 50 56 0» 3 Ό ΟΝ*. ,.,- 'S’ * Φ OK ΐ Ό - - *— rl Qj w 4-» • L * ID 4-> L· *-> c ID a 4-> •f- ID X o c a rg rv Ό ΚΪ O Φ U O) - *“ CM r\j a a X O O o O o O 3 re in o o 0» c* ^ «>.£ ®j> o .98 Ό O' 'S' ¢0 07 s CO •s Κ» c Φ -* 5 o 3 Pw Κ» -s V- tn T~ 13. 'S T“ ω u. a K T- 3 X · o O' o O' o Ov O O' o O' o K- *Z £x *Λ D) .92 ,39 o Ki Ό •s CM 'S -s *o •r- 3 ΙΛ £« 5~l 15. «r- V *· cr • .u 3 _/ cm l*_ (0 ·· 3 O X Φ a X Ki Ό Ό M c ft> D> ΌΪ Pw N- P- X o O o O o o O E O X Ό N 00 o OJ CM 63 k? Ό l~ s fw «S1 S NS Ki o 1! ΙΛ o m X K* 4-* T"· ro

Claims (8)

1. A product for feeding ruminants which is formed by reaction of urea with a lactose-containing material the lactose of which has previously been 5 at least partially hydrolyzed to glucose and galactose, and wherein the product contains less than 2% by weight of free urea.

2. A product as claimed in claim 1 which contains 5 to 40% by weight of urea.

3. 103. A product as claimed in claim 2, which contains 15 to 30% by weight of urea.

4. A product as claimed in any of claims 1 to 3 wherein the lactose-containing material is a lactoserum permeate or a lactose-containing 15 liquor, the lactose of which has been previously at least partially hydrolyzed to glucose and galactose.

5. A product as claimed in any of claims 1 to 4, wherein the lactose-containing material has been 20 at least partially hydrolyzed with the aid of immobilized lactase or |?-galactosidase.

6. A product as claimed in any of claims 1 to 5, which additionally contains phosphoric acid.

7. A product as claimed in claim 6, wherein the 25 proportion of H3PO4 is between 2 and 7% by weight relative to the total weight of the product. -10- A process for preparing a product for feeding ruminants as claimed in claim 1, which process comprises the following steps: dissolving urea in a lactose-containing material, the lactose of which has been at least partially hydrolyzed, at a temperature of 50-90°C, with agitation; adjusting the pH, if necessary, in the range from 2.5 to 4.5 by adding acid to the solution obtained; and heating the resultant acid solution at a temperature of 50-90°C for a time sufficient for the free urea content of the resulting product not to exceed 2% by weight. A process as claimed in claim 8, wherein the adjustment of the pH is produced by adding phosphoric acid. A product substantially as hereinbefore described with reference to the Examples. A process substantially as hereinbefore described with reference to the Examples. Dated the 22nd day of December 1983 Cruickshank & Co Agents for the Applicants

8. 1 Holies Street Dublin 2.