IE48245B1 - Dairy sanitisation - Google Patents

Description

The present invention relates to sanitisation.

More particularly it relates to sanitisation in the dairy industry, e.g. udder sanitisation, using compositions based on glutaraldehyde.

One of the best known and most efficient sterilizing agents is glutaraldehyde. However, glutaraldehyde suffers from certain disadvantages. Glutaraldehyde in acid solution is relatively stable but has very poor sporicidal activity. In alkaline solutions it is effect10 ive but not very stable. Attempts have been made to overcome these disadvantages by storing the glutaraldehyde under acid conditions and then, just prior to use, adjusting the pH of the aqueous solution of glutaraldehyde to alkaline. Such action however imposes an undesirable burden upon the user .

Very recently, various proposals have been made to obviate the alkalinization procedure. It has been proposed to incorporate various additives into the aqueous glutaraldehyde to produce stable but active solutions which do not require alkalination prior to use. In Patent Specification No. 47504 there is described and claimed a composition for sterilizing and disinfecting which comprises water or a mixture of water and a lower monohydric alcohol, glutaraldehyde and divalent and/or trivalent metal ions. The composition is preferably at a pH not above 7. 4-8 2 4 5 - 3 Such compositions may also include surfactants, either as separate compounds from the compounds providing the trivalent or divalent metal ions or as single compounds providing both the metal ions and the surfactant components. Such compounds will be further described hereinafter . However it has been found that use of such compositions in the treatment of animals can lead to problems. For example, prolonged use of the compositions as udder sanitising agents can cause widespread incidence of teat cracking. Cracks or fissures in the dermal tissue of the cow's teat act as a residence point for bacterial colonies and it is difficult to penetrate these points with any type of waterborne disinfectant. One factor which may produce the dermatological changes resulting in cracking is the denuding of the skin’s natural protective fats by a process of emulsification. The presence of some surfactants in the working formulations would assist this emulsification.

It has now been found possible to reduce the problem of teat cracking.

According to one embodiment of the present invention there is provided a method of sanitising in the dairy industry which comprises applying to a site on or in an animal to be treated a composition comprising water or a mixture of water and a monohydric alcohol having 1 to 3 carbon atoms, glutaraldehyde, a divalent and/or trivalent metal ion and a lipid soluble emollient.

The presence of a lipid soluble emollient in such compositions substantially overcomes the teat cracking.

It is believed that the emollient is adsorbed into the udder dermal tissues, producing an emollient action which succeeds in suppressing teat cracking. The 8 2 4 5 - 4 emollient conditions the skin of animals by replacing the natural oils which may be removed by other constituents in compositions such as those described and claimed in the copending Application identified hereinabove.

The lipid soluble emollient is preferably a polyalkylene oxide derivation of waxy esters and the like.

The waxy esters can be in the form of lanolin. Suitable emollients include the polyalkylene oxide derivatives of lanolin such as an ethoxylated lanolin, particularly when the degree of ethoxylation is within the range of 40 to 70 mols of ethylene oxide. However any other water soluble polyalkylene oxide derivative of lanolin may be employed. Other lipid soluble emollients can be employed. Examples are solubilized mixtures of alkyl branched fatty acid polyglycol esters such as Neo-PCL water soluble.

The amount of emollient can be as low as 0.5% weight/volume based on the composition. However it is preferred to use substantially 2% weight/volume of the composition. However, such concentrations are based on the solution as used in treatment. It is possible to provide the formulation in a concentrated form which may be diluted for example, ten times prior to use.

The compositions of the present invention may also contain a small quantity of an organic acid such as citric acid, propionic acid, tartaric acid or maleic acid. The presence of an organic acid ensures an acid pH for the formulation, this being normal for teat tissue and generally desirable for glutaraldehyde stability.

For the sake of convenience, the present invention will be particularly described with reference to the use 3+ 2+ of Al or Mg as the metal ion. However other trivalent and divalent metal ions may be used. In the Α8 2Λ5 - 5 case of divalent ions it is preferred to use alkaline earth inetal ions while in the case of trivalent ions, the preferred ions are those of Group Illb of the Periodic Table of Elements e.g. aluminium. The metal ions can be introduced in salt form such as sulphate or halide (Particularly chloride), for example aluminium chloride or magnesium chloride. Referring again to the investig3+ 2+ ations described above, the presence of Al or Mg in aqueous glutaraldehyde solutions was found to increase glutaraldehyde inactivation of cellular alkaline phosphatase by causing a drift of the enzyme towards the outer membrane. A still further increase in activity was demonstrated when a surfactant, preferably of the anionic type, was added to the aluminium-glutaraldehyde or magnesium-glutaraldehyde formulation and this effect was related to increased uptake of the disinfectant.

As mentioned above, acidic solutions of glutaraldehyde have very slow activity. However it has been found , that an aqueous acidic solution of glutaraldehyde contain- I 3+ 2+ ing Al or Mg has comparable activity to an aqueous solution of glutaraldehyde made alkaline by the presence of, for example, sodium bicarbonate.

Study of the effect of varying concentrations of 3+ 2+ A1 or Mg on the effectiveness of the glutaraldehyde solution has shown increasing effectiveness up to about 0.2 Molar but no significant increase for concentrations over 0.2 Molar. However concentrations as high as 0.5 Molar may be used. It is preferred to use a concen3+ 2+ tration for Al or Mg of at least 0.15 Molar.

Extrapolation of investigations on bacteria to spores has shown similar results. 8 2 1 5 - 6 The incorporation of a surfactant into the glutar3+ 2+ aldehyde-Al or glutaraldehyde-Mg solution potentiates the effect of the glutaraldehyde. Indeed it has been found that in some cases a synergistic effect is achieved 3+ when compared with aqueous glutaraldehyde containing Al 2+ or Mg or surfactant alone.

The preferred surfactants are anionic. Suitable anionic surfactants include detergents which are ionizable at the pH of acid solutions of glutaraldehyde. The pKa values would generally be less than 4, preferably less than 3.5. The anionic surfactants may be, for example, alkyl sulphates or alkylaryl sulphonates. The alkyl sulphates usually have 8 to 18 carbon atoms in the alkyl group, for example lauryl or dodecyl sulphate. The anionic surfactant is usually employed in an amount of less than 10% by weight, preferably less than 5% by weight when using an alkyl sulphate.

Non-ionic surfactants such as the ethoxylated fatty alcohols or ethoxylated alkylphenols may be used.

Preferably the fatty alcohol or alkyl phenol has been ethoxylated to a degree of greater than 9 moles of ethylene oxide. However, use of a non-ionic surfactant 3+ 2+ with Al or Mg has been found not to be as effective as use of an anionic surfactant (as sodium salt) with 3+ 2+ Al or Mg . The non-ionic surfactant is usually employed in an amount of less than 3% by weight, preferably 0.5 to 1.5% by weight. 3+ 2+ Use of fairly high concentrations of Al or Mg (or indeed other trivalent or divalent metal ions) salts and fairly high concentrations of surfactants can however lead, in some instances, to a salting out effect resulting in precipitation from the solution. This - 7 3-h problem can however be overcome by employing the Al or 2+ Mg and surfactant aa a single compound. When using such single compounds, the trivalent or divalent metal ions are cations of surfactants, preferably anionic surfactants. Examples of such compounds are aluminium dodecyl or lauryl sulphate, aluminium dodecyl or lauryl benzene sulphonate magnesium dodecyl or lauryl sulphate and magnesium dodecyl or lauryl benzene sulphonate.

Indeed if a single compound is used it is possible to produce effective formulations of glutaraldehyde containing less than the desired 0.15 Molar concentration of 3+ 2+ A1 or Mg , even as low as 0.001 Molar.

The concentration of glutaraldehyde in the aqueous solution affects the time required for sanitisation.

The concentration of glutaraldehyde is usually from 0.005 to 10%, but preferably less than 0.5% by weight of the solution.

As stated above, alkaline solutions of glutaraldehyde have greater activity than acid solutions. A 3+ similar difference occurs in solutions containing Al 2+ or Mg (alone or with surfactant). However, such alkaline solutions have reduced stability compared with acid solutions. If it is desired to use an alkaline pH any conventional alkalinating agent, for example, sodium bicarbonate, may be used.

The compositions of the present invention are temperature dependent in use. Increasing temperature (particularly with acid solutions) leads to increasing activity and indeed a synergistic effect may be observed. The compositions are usually employed at a temperature of at least ambient temperature. - 8 If a mixture of water and alcohol is used in the composition of the present invention, the alcohol may be, for example, isopropanol. The presence of an alcohol, or indeed another organic solvent, can be used to control the viscosity of the solution or produce a humectant effect.

The compositions of the present invention may be used in sanitisation in the presence of metallic, particularly ferrous, articles. However, at acid pH, many of the conventional additives for rust inhibition have been demonstrated to be ineffective for the formulations of the present invention. It has been further demonstrated that the sulphate or sulphonate derivatives of hydroxy carboxylic acids, such as those derived from ricinoleic and hydroxy-stearic acids, are effective corrosion inhibitors for the formulation of this invention. The aforementioned sulphate and sulphonated derivatives or hydroxy carboxylic acids are also anionic surfactants. It is further possible by the use of the said carboxylic acids, to present the preferred ion, anionic surfactant and corrosion or rust inhibitor in the form of a single compound. The amount of corrosion or rust inhibitor employed is usually 0.1 to 5% by weight, preferably substantially 1% by weight, of the composition. A particularly useful inhibitor is sulphated caster oil (marketed by Ellis Jones + Co.), preferably in the presence of an organic acid (e.g. citric acid) to ensure an acid pH.

While the compositions for use in the present invention have hereinabove been described with particular reference to the external treatment of animals, it is possible to use similar compositions for internal treatment. 8 2 4 5 - 9 According to another embodiment of the present invention there is provided a method of treating animals which comprises intermammary injection of a composition comprising water or a mixture of water and a monohydric alcohol having 1 to 3 carbon atoms, glutaraldehyde, a divalent and/or trivalent metal ion, a lipid soluble emollient and a gelling agent. The gelling agent is one which does not react with glutaraldehyde and generally has a non-protein base. The gelling agent may be a water-soluble cellulose derivative such as an ether, for example hydroxypropyl cellulose. The amount of gelling agent is generally 0.5 to 5%, preferably 1 to 2%, by weight. The composition for injection may also contain glycerine, usually in an amount of 5 to 20%, preferably substantially 15%, by weight.

The present invention will now be further described with reference to, but is in no manner limited to, the following Examples.

Example 1 0.1% by weight glutaraldehyde, 4.0% by weight magnesium chloride hexahydrate and 2.0% by weight ethoxylated lanolin were dispersed in water and successfully used as a sanitising formulation for dairy purposes.

Example 2 0.5% by weight glutaraldehyde, 4.0% by weight magnesium chloride hexahydrate, 2.0% by weight ethoxylated lanolin and 10.0% by weight isopropanol were dispersed in water. The resulting formulation was used in sanitising of cows' udders. - 10 Example 3. 0.5% by weight glutaraldehyde, 7.0% by weight magnesium lauryl sulphate, 3.0% by weight ethoxylated lanolin and 0.5% by weight citric acid were dispersed in water. The formulation so produced was effective in the sanitisation of cows' udders.

Example 4 0.1% by weight glutaraldehyde, 4.0% by weight magnesium chloride hexahydrate and 1.5% by weight Neo10 PCL water soluble were dispersed in water and successfully used as a sanitising agent for dairy purposes.

Claims (52)

1. A method of sanitising in the dairy industry which comprises applying to a site on or in an animal to be treated a composition comprising water or a mixture of water and a monohydric alcohol having 1 to 3 carbon atoms, glutaraldehyde, a divalent and/or trivalent metal ion and a lipid soluble emollient.

2. A method as claimed in claim 1 in which the trivalent metal ion is a cation of a surfactant.

3. A method as claimed in claim 2 in which the trivalent metal ion is a cation of an anionic surfactant.

4. A method as claimed in claim 3 in which the trivalent metal ion is present in the form of aluminium dodecyl or lauryl sulphate or aluminium dodecyl or lauryl benzene sulphonate.

5. A method as claimed in claim 1 in which the divalent metal ion is a cation of a surfactant.

6. A method as claimed in claim 5 in which the divalent metal ion is a cation of an anionic surfactant.

7. A method as claimed in claim 6 in which the divalent metal ion is present in the form of magnesium dodecyl or lauryl sulphate or magnesium dodecyl or lauryl benzene sulphonate.

8. A method as claimed in claim 1 in which the trivalent metal ion is a cation of Group 111(b) metals.

9. A method as claimed in claim 8 in which the trivalent metal ion is present in the form of a chloride or sulphate salt.

10. A method as claimed in claim 9 in which the trivalent metal ion is present in the form of aluminium chloride. - 12

11. A method as claimed in claim 1 in which the divalent metal ion is a cation of alkaline earth metals.

12. A method as claimed in claim 11 in which the divalent metal ion is present in the form of a chloride or sulphate salt.

13. A method as claimed in claim 12 in which the divalent metal ion is present in the form of magnesium chloride.

14. A method as claimed in any of claims 1 and 8 to 13 in which the divalent and/or trivalent metal ion is present in a concentration of at least 0.15 molar.

15. A method as claimed in any of claims 1 and 8 to 14 in which the divalent and/or trivalent metal ion is present in a concentration of not more than 0.5 molar.

16. A method as claimed in any of claims 2 to 7 in which the divalent and/or trivalent metal ion is present in a concentration of at least 0.001 molar.

17. A method as claimed in any of claims 2 to 7 and 16 in which the divalent and/or trivalent metal ion is present in a concentration of not more than 0.5 molar.

18. A method as claimed in any of claims 1 and 8 to 15 in which the composition also contains a surfactant

19. A method as claimed in claim 18 in which the surfactant is an anionic surfactant.

20. A method as claimed in claim 19 in which the anionic surfactant has a pKa of less than 4.

21. A method as claimed in claim 19 or 20 in which the anionic surfactant is an alkyl sulphate or alkylaryl sulphonate.

22. A method as claimed in claim 21 in which the alkyl sulphate is dodecyl or lauryl sulphate. 4 8 2 4 5 - 13

23. A method as claimed in claim 18 in which the surfactant is a non-ionic surfactant.

24. A method as claimed in claim 23 in which the non-ionic surfactant is an ethoxylated fatty alcohol or alkyl phenol which have been ethoxylated to a degree of greater than 9 moles of ethylene oxide.

25. A method as claimed in any of claims 1, 8 to 15 and 18 to 24 in which the divalent and/or trivalent metal ion is added to the composition in the form of a simple inorganic salt.

26. A method as claimed in claim 25 in which the salt is magnesium chloride or aluminium chloride.

27. A method as claimed in any of- claims 1 to 26 which also contains a corrosion inhibiting agent.

28. A method as claimed in claim 27 in which the corrosion inhibiting agent is a sulphated or sulphonated hydroxy carboxylic acid.

29. A method as claimed in claim 28 in which the corrosion inhibiting agent is a sulphate or sulphonate derivative of ricinoleic or hydroxy stearic acid.

30. A method as claimed in any of claims 2 to 7 in which the metal ion-containing surfactant is selected so that it has, in addition to surfactant properties, corrosion inhibiting properties.

31. A method as claimed in claim 30 in which the metal ion-containing surfactant is derived from a sulphated or sulphonated hydroxy carboxylic acid.

32. A method as claimed in claim 31 in which the metal ion-containing surfactant is derived from a sulphate or sulphonate derivative of ricinoleic or hydroxy stearic acid. - 14

33. A method as claimed in any of claims 27 to 32 in which the corrosion inhibiting agent is present in a concentration of 0.1 to 5% by weight of the composition.

34. A method as claimed in any of claims 1 to 33 in which the glutaraldehyde is present in a concentration of 0.005 to 10% by weight of the composition.

35. A method as claimed in claim 34 in which the glutaraldehyde is present in a concentration of less than 0.5% by weight of the composition. 36 . A method as claimed in any of claims 1 to 35 in which the composition has a pH not above 7. 37 . A method as claimed in any of claims 1 to 36 in which the emollient is present in an amount of at least 0.5% weight/volume of the composition.

36. 38. A method as claimed in claim 37 in which the emollient is present in an amount of substantially 2% weight/volume of the composition.

37. 39. A method as claimed in any of claims 1 to 38 in which the emollient is a polyalkylene oxide derivative of waxy esters.

38. 40. A method as claimed in claim 39 in which the emollient is a polyalkylene oxide derivative of lanolin.

39. 41. A method as claimed in claim 39 or 40 in which the emollient is a polyethylene oxide derivative.

40. 42. A method as claimed in claim 41 in which the emollient is an ethoxylated lanolin having a degree of ethoxylation of 40 to 70 mols ethylene oxide.

41. 43. A method as claimed in any of claims 1 to 38 in which the emollient is a solubilized mixture of alkyl branched fatty acid polyglycol esters.

42. 44. A method as claimed in claim 43 in which the emollient is Neo-PCL water soluble. 4-824-5 - 15

43. 45. A method as claimed in any of claims 1 to 44 in which an organic acid is present.

44. 46. A method of treating animals which comprises intermammary injection of a composition comprising water or a mixture of water and a monohydric alcohol having 1 to 3 carbon atoms, glutaraldehyde, a divalent and/or trivalent metal ion, a lipid soluble emollient and a gelling agent.

45. 47. A method as claimed in claim 46 in which the gelling agent is a water soluble cellulose derivative.

46. 48. A method as claimed in claim 47 in which the gelling agent is a water soluble cellulose ether.

47. 49. A method as claimed in claim 48 in which the gelling agent is hydroxypropyl cellulose.

48. 50. A method as claimed in any of claims 46 to 49 in which the gelling agent is present in an amount of 0.5 to 5% by weight of the composition.

49. 51. A method as claimed in claim 50 in which the gelling agent is present in an amount of 1 to 2% by weight of the composition.

50. 52. A method as claimed in any of claims 46 to 51 in which glycerine is also present.

51. 53. A method as claimed in claim 52 in which glycerine is present in an amount of 5 to 20% by weight of the composition.

52. 54. A method of sanitising or treating animals substantially as hereinbefore particularly described.