A solid propylene glycol derived material

Abstract

An energy efficient method of rapidly producing a solid metal-stabilised, propylene glycol-derived material, the method including a step of combining propylene glycol having a water content of up to about 50% by weight with a metal oxide and an accelerator, so that an exothermic reaction is created transforming the liquid propylene glycol starting material into a solid, metal-stabilised, propylene glycol- derived material. The invention also relates to a solid metal-stabilised propylene glycol derived material and to an animal feed composition comprising the solid metal-stabilised propylene glycol derived material.

Description

[0001] Title of the Invention

[0002] A Solid Propylene Glycol Derived Material

[0003] Field of the Invention

[0004] This invention relates to a method of producing a solid propylene glycol derived material and to a solid metal-stabilised propylene glycol derived material produced by the method. The invention also relates to an animal feed composition comprising the solid metal-stabilised propylene glycol derived material.

[0005] Background of the Invention

[0006] Propylene glycol (IIIPAC name: propane-1 ,2-diol) is a viscous, sticky, colourless liquid, which is nearly odourless with a faintly sweet taste and is soluble in water. Its chemical formula is CH3CH(OH)CH2OH.

[0007] Commercially, propylene glycol is mainly produced from propylene oxide for foodgrade use and manufacturers use either a non-catalytic high-temperature process at 200°C to 220°C or a catalytic method at 150°C to 180°C in the presence of ion exchange resin or a small amount of sulphuric acid or alkali to produce the colourless liquid.

[0008] Propylene glycol is often used as a supplemental energy source (glucose precursor) in ruminant nutrition and is also used as an oral treatment for ketosis in ruminants when the negative energy balance during the early stages of lactation can cause the animal's body to have lower glucose levels, inducing the liver to make up for this by the conversion of body fat, leading to several health conditions, for example displaced abomasum. It must generally be provided in its liquid form as a drench as large doses (>500 g / d) can have toxic and side effects on dairy cows due to the toxic compounds produced from propylene glycol during metabolic processes in the rumen and elsewhere. Clinical signs of propylene glycol in toxic doses include depression, ataxia, and excessive salivation as well as abnormal, malodorous, and foul breath and faeces in dairy cows. However, due to its sticky viscous nature, drenching with propylene glycol can also be problematical.

[0009] The toxicity and side effects of propylene glycol therefore limit the maximum dosage as a supplemental energy source in dairy cows and as an oral treatment to reduce the risk of ketosis. However, the side effects of propylene glycol are related to individual cow susceptibility, so it is important to consider the signs of toxicity in the administering of propylene glycol with the result that the maximum feeding level of propylene glycol is 500 g per cow per day.

[0010] When used as a supplemental energy source, the propylene glycol is believed to improve the molar proportion of ruminal propionate and hepatic gluconeogenesis in cows, which results in an elevation of serum glucose and decrease in serum non- esterified fatty acid (NEFA) and beta-hydroxy butyric acid (BHBA). Therefore, the drenching of propylene glycol during the transition period is beneficial for the dairy cows to alleviate NEB postpartum. However, as indicated above, the feeding level and method may affect the effects of propylene glycol administration.

[0011] As an alternative to liquid drenches, products in which the liquid propylene glycol is absorbed onto solid carriers for example cellulose or silica are also available as feed materials. For example, Chung et al. verified feeding propylene glycol as a dry product (65% propylene glycol and 35% silicon dioxide as the carrier) in total mixed rations (TMR) also reduced plasma BHBA concentration. (Chung Y.H., Brown N.E., Martinez C.M., Cassidy T.W., Varga G.A. Effects of rumen-protected choline and dry propylene glycol on feed intake and blood parameters for Holstein dairy cows in early lactation. J. Dairy Sci. 2009;92:2729-2736. doi: 10.3168 / jds.2008-1299).

[0012] However, the same amount of propylene glycol as a top dress (500 g / d of cookie meal, a dried bakery by-product, mixed with dry propylene glycol) was more efficient than incorporating it into the total mixed ration (TMR). The administration method therefore seems to be of importance for the metabolic response of propylene glycol in cows because the response of allocating propylene glycol as an oral drench or in a separately fed concentrate, is better than mixing into TMR (Bjerre-Harpoth V., Storm A.C., Eslamizad M., Kuhla B., Larsen M. Effect of propylene glycol on adipose tissue mobilization in postpartum over-conditioned Holstein cows. J. Dairy Sei. 2015;98:8581-8596. doi: 10.3168 / jds.2O14-8606).

[0013] However, liquid propylene glycol is not easily employed as a top dress due to its sticky, viscous properties and as it can also negatively impact the taste and texture of animal feeds while the silica required for the solid carrier with dry propylene glycol is costly and does not have any nutritional value. In addition, regular or daily drenching with liquid propylene glycol is not feasible or viable due to the labour required.

[0014] In addition, neither the liquid propylene glycol nor the propylene glycol on a silica carrier is protected from being fermented in the rumen. More particularly, both forms are also subject to fast rumen fermentation into large volumes of carbon dioxide gas (forming carbonic acid when dissolved in rumen fluid) and volatile fatty acids i.e. acetic acid, propionic acid and butyric in the rumen (of which only propionic acid / propionate is a glucose precursor). This means that a large proportion of the product being fed is not converted to glucose in the cow and also risks acidification of the rumen exacerbating sub-acute ruminal acidosis (SARA), reduced feed intakes and the risk of exacerbation of other metabolic disorders, etc.

[0015] US4,680,315 describes a mixture comprising propylene glycol and magnesium oxide and / or magnesium peroxide as a solid carrier(s). The mixture is described as for use as solid propylene glycol in dietetic products for calf, piglet and lamb and for use in other pharmaceutical compositions for veterinary use. A method of preparing the product is also described and involves spraying propylene glycol to the carrier.

[0016] GB2153669 discloses a fodder concentrate having propylene glycol which is bound to a solid carrier. A method of preparing the product is also described and involves spraying propylene glycol to the carrier.

[0017] An object of the invention is to overcome at least some of the problems of the prior art. Summary of the Invention

[0018] The Applicant has developed an energy efficient process to rapidly transform propylene glycol, a viscous liquid into solid, particulate metal-stabilised materials such as powders, flours, granules and the like with water released as steam as the only byproduct of the process. The Applicant has also developed novel solid propylene glycol derived materials.

[0019] In a first aspect, the invention relates to a method of producing a solid metal-stabilised propylene glycol derived material comprising: combining propylene glycol with a metal oxide and an accelerator, the propylene glycol having a water content of up to about 50% by weight, and creating an exothermic reaction to transform the liquid propylene glycol into a solid metal-stabilised propylene glycol derived material.

[0020] In any embodiment, the propylene glycol has a water content of up to about 30% by weight.

[0021] In any embodiment, the propylene glycol has a water content of up to about 25% by weight

[0022] In any embodiment, the propylene glycol has a water content of from about 5% to about 30% by weight.

[0023] In any embodiment, the propylene glycol has a water content of from about 10% to about 25% by weight.

[0024] In any embodiment, the metal oxide is selected from Group 1A metal oxides, Group 2A metal oxides, transition metal oxides and combinations thereof.

[0025] In any embodiment, the metal oxide is calcium oxide.

[0026] In any embodiment, the calcium oxide has a purity of at least about 75%. In any embodiment, the metal oxide optionally contains a metal hydroxide and / or a metal carbonate.

[0027] In any embodiment, the accelerator comprises a propylene glycol acidifier.

[0028] In any embodiment, the acidifier is selected from the group comprising an inorganic acid, and / or an organic acid, and / or a combination thereof.

[0029] In any embodiment, the inorganic acid is selected from phosphoric acid, sulphuric acid, hydrochloric acid and / or a combination thereof.

[0030] In any embodiment, the organic acid is selected from the group comprising amino acids for example methionine and / or lysine, amino acid analogues or amino acid derivatives for example methane hydroxy analogue (MHA), alkyl carboxylic acids, hydroxyalkyl carboxylic acids, lactic acid, propionic acid, fatty acids, salts thereof and / or a combination thereof.

[0031] In any embodiment, the fatty acid is a short-, medium or long-chain saturated or unsaturated fatty acid or a mixture thereof.

[0032] In any embodiment, the fatty acid is selected from the group comprising palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid and / or a combination thereof.

[0033] In any embodiment, the method further comprises the step of combining an inorganic salt with the propylene glycol, the metal oxide and the accelerator.

[0034] In any embodiment, the inorganic salt is selected from the group comprising calcium hydroxide, calcium carbonate, a calcium phosphate salt or salts, calcium sulphate, magnesium hydroxide, magnesium carbonate, a magnesium phosphate salt or salts, magnesium sulphate or a combination thereof.

[0035] In any embodiment, the method further comprises the step of combining an additional feed component with the propylene glycol, the metal oxide and the accelerator. In any embodiment, the additional feed component is selected from the group comprising vitamins, minerals, trace elements, proteins, carbohydrates, oils, choline and choline salts, betaine and betaine salts, phospholipids / lecithins, metal salts, yeasts, flavouring agents, colouring agents or mixtures thereof.

[0036] In any embodiment, the oils are selected from the group comprising plant-based oils rich in omega-3 and / or omega-6 fatty acids, olive oil, rapeseed oil, canola coil, palm oil, sunflower oil, linseed oil, flax seed oil, coconut oil, sunflower oil, soybean oil, fish oil and the like, or combinations thereof.

[0037] In any embodiment, the propylene glycol is partially substituted by glycerol.

[0038] If desired, the method of the invention can include heating of the reaction vessel and / or the reaction mixture and / or the starting materials and / or the reaction product.

[0039] The method of the invention can also include the steps of flavouring and / or colouring and / or drying and / or heating and / or steaming and / or pelletising and / or other steps of further processing or any combinations of these of the reaction product after the exothermic reaction is completed.

[0040] The starting materials with or without additional feed component(s) can be combined and mixed in any order or sequence and using any type of equipment. For example, the additional feed component(s) can be added to the starting materials, during the process or to the reaction product in any order or sequence and using any type of equipment.

[0041] The process employed in the method of the invention can be a batch process, continuous process, semi-batch process, semi-continuous process, manual, automated, semi-automated or any variation of these process types at any scale.

[0042] The invention therefore provides a method of producing a solid metal-stabilised propylene glycol derived material, the method including the step of combining acidic propylene glycol or propylene glycol-water mixtures with a metal oxide, for example calcium oxide, the propylene glycol having a water content of up to about 50% by weight so that an exothermic reaction is created in which the solid propylene glycol derived material is produced.

[0043] The invention therefore can relate to a method of producing a calcium salt of propylene glycol, the method including the steps of combining propylene glycol with calcium oxide and at least one acid, the propylene glycol having a water content of up to about 50%, and the combination of the propylene glycol and acid and the calcium oxide and the amount of the acid and calcium oxide being selected so that an exothermic reaction is created to provide a calcium salt of propylene glycol in the form of a solid, calcium-stabilised, propylene glycol-derived product.

[0044] The invention also relates to a novel solid propylene glycol derived material produced according to the method which can be used as an animal feedstuff.

[0045] The invention therefore also provides a method of rapidly producing an animal feed composition such as a feedstuff or a feedstuff supplement, the method including the steps of combining propylene glycol with calcium oxide and optionally a metal hydroxide and at least one accelerator, the propylene glycol having a water content of up to about 50% by weight, and the rate of combination of the propylene glycol and the calcium oxide and the amount of the calcium oxide being selected so that an exothermic reaction is created to produce the animal feedstuff or feedstuff supplement, the accelerator being selected from inorganic acids, organic acids and / or other components as described above and combinations thereof. The inorganic and organic acids may be as hereinbefore described.

[0046] The method of the invention thus provides a method of converting propylene glycol, a viscous, sticky liquid which is a glucose pre-cursor into an easy-to-use rumen- protected animal feedstuff or animal feed supplement by reacting propylene glycol with calcium oxide and an accelerator (e.g. an acid such as phosphoric acid or sulphuric acid) to rapidly and energy-efficiently produce the feedstuff or supplement. The invention also relates to a solid metal-stabilised propylene glycol derived material produced according to a method of the invention.

[0047] In a second aspect, the invention relates to a solid metal-stabilised propylene glycol derived material comprising propylene glycol and a metal salt to stabilise the propylene glycol.

[0048] Accordingly, there is provided a solid metal-stabilised propylene glycol derived material comprising: from about 20% to about 80% by weight propylene glycol, and from about 5% to about 40% by weight a metal or combination of metals.

[0049] In one embodiment, the solid metal-stabilised propylene glycol derived material product comprises from about 30% to about 70% by weight propylene glycol.

[0050] In any embodiment, the solid metal-stabilised propylene glycol derived material product comprises from about 5% to about 60% by weight propylene glycol.

[0051] In any embodiment, the solid metal-stabilised propylene glycol derived material product comprises from about 5% to about 40% by weight a metal or combination of metals.

[0052] In any embodiment, the metal is part of a metal salt which comprises an inorganic and / or an organic metal salt.

[0053] In any embodiment, the metal in the metal salt comprises a Group 1A, a Group 2A or a transition metal or a combination thereof.

[0054] In any embodiment, the inorganic salt comprises a phosphate, sulphate, or chloride salt or a combination thereof. In any embodiment, the inorganic salt comprises a phosphate salt such as, but not limited to, calcium phosphate [Cas(PO4)2] or dicalcium phosphate [CaHPO4] or a sulphate salt such as calcium sulphate [CaSO4] or combinations of such salts.

[0055] In any embodiment, the organic salt comprises a salt of an amino acid for example methionine and / or lysine, amino acid analogue / derivative for example methionine hydroxy analogue (MHA), alkyl carboxylic acid, hydroxyalkyl carboxylic acid, lactic acid, propionic acid, fatty acid, or a combination thereof.

[0056] In any embodiment, the fatty acid is a short-, medium or long-chain saturated or unsaturated fatty acid or mixtures thereof.

[0057] In any embodiment, the fatty acid is selected from the group comprising palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid or a combination thereof.

[0058] In any embodiment, the organic salt comprises a mono- and / or di-ester salt.

[0059] In any embodiment, the solid metal-stabilised propylene glycol derived material further comprises an inorganic salt.

[0060] In any embodiment, the inorganic salt is selected from the group comprising calcium hydroxide, calcium carbonate, a calcium phosphate salt or salts, calcium sulphate, magnesium hydroxide, magnesium carbonate, a magnesium phosphate salt or salts, magnesium sulphate or a combination thereof.

[0061] In any embodiment, the solid metal-stabilised propylene glycol derived material further comprises an additional feed component or components selectable from the group comprising vitamins, minerals, trace elements, proteins, carbohydrates, oils, choline and choline salts, betaine and betaine salts, phospholipids / lecithins, metal salts, yeasts, flavouring agents, colouring agents or a combination thereof.

[0062] In any embodiment, the oils are selected from the group comprising plant-based oils rich in omega-3 and / or omega-6 fatty acids, olive oil, rapeseed oil, canola coil, palm oil, sunflower oil, linseed oil, flax seed oil, coconut oil, sunflower oil, soybean oil, fish oil and the like, or a combination thereof.

[0063] In any embodiment, the propylene glycol is partially substituted with glycerol.

[0064] In any embodiment, up to 50% by weight of the propylene glycol is substituted by glycerol.

[0065] In another embodiment, the invention also extends to an animal feed composition comprising a solid propylene glycol derived material as hereinbefore defined.

[0066] In any embodiment, the animal feed composition is a particulate feed composition.

[0067] In any embodiment, the particulate feed composition comprises a powder, a flour or granules.

[0068] In any embodiment, the propylene glycol or propylene glycol and glycerol combination in the feed composition is at least partially protected from being fermented in a rumen.

[0069] By being metal-stabilised, the solid propylene glycol materials of the invention are largely protected against being fermented in the rumen. Feed compositions formed from the solid metal-stabilised propylene glycol materials mostly by-pass the rumen to the acidic abomasum where it is released as the powder dissolves in the acidic fluid of the abomasum. The propylene glycol is then transported to the liver where it is efficiently enzymatically converted to glucose. Feed compositions formed from the solid metal-stabilised propylene glycol materials therefore provide an efficient / economic method of providing energy to dairy cows. Accordingly, dairy cows can be more easily protected against metabolic disorders such as sub-clinical ketosis, sub-acute ruminal acidosis (SARA), etc. with beneficial effects in terms of general health and welfare through improved body condition, fertility, milk yields, etc. being possible. As indicated above, liquid propylene glycol products are typically fed to dairy cows through drenching or through a liquid dosing device. However the liquid, being viscous and “sticky”, is not easily or efficiently fed to the dairy cows. In contrast, the solid metal-stabilised propylene glycol glucose precursor materials of the invention can be easily and efficiently fed via a robotic system to dairy cows. Accordingly, propylene glycol based glucose precursors in the form of a powder, granules or the like can now be selectively fed as required to ruminants on farm. Appropriate dosages can therefore be fed to the animals and overdosages are more easily avoided.

[0070] The invention therefore provides superior targeted energy provision to ruminants as opposed to simply feeding freely fermentable, rumen-unprotected propylene glycol as either liquids or liquids on cellulose- or silica-based materials to the ruminants.

[0071] Definitions and General Preferences

[0072] All publications, patents, patent applications and other references mentioned herein are hereby incorporated by reference in their entireties for all purposes as if each individual publication, patent or patent application were specifically an individually indicated to be incorporated by reference and the content thereof recited in full.

[0073] Where used herein and unless specifically indicated otherwise, the following terms are intended to have the following meanings in addition to any broader (or narrower) meanings the terms might enjoy in the art:

[0074] Unless otherwise required by context, the use herein of the singular is to be read to include the plural and vice versa. The term "a" or "an" used in relation to an entity is to be read to refer to one or more of that entity. As such, the terms "a" (or "an"), "one or more," and "at least one" are used interchangeably herein.

[0075] As used herein, the term "comprise," or variations thereof such as "comprises" or "comprising," are to be read to indicate the inclusion of any recited integer (e.g., a feature, element, characteristic, property, method / process step or limitation) or group of integers (e.g., features, element, characteristics, properties, method / process steps or limitations) but not the exclusion of any other integer or group of integers. Thus, as used herein the term "comprising" is inclusive or open-ended and does not exclude additional, unrecited integers or method / process steps.

[0076] Detailed Description of the Invention

[0077] The "solid propylene glycol derived materials" of the invention include materials in the form of powders, flours, granules, flakes, particles, pieces, combinations of these and the like. Generally, the method of producing the solid propylene glycol derived material of the invention includes the step of combining acidic propylene glycol or propylene glycol-water mixtures with a metal oxide, for example calcium oxide, the propylene glycol having a water content of up to about 50% by weight so that an exothermic reaction is created in which the solid propylene glycol derived material is produced.

[0078] The propylene glycol employed in the method of the invention is a liquid propylene glycol produced by any method known in the art. The propylene glycol has a water content sufficient to generate an exothermic reaction which is generally up to about 50% by weight. Typically, the propylene glycol will have a water content of between about 10% and 25% (w / w). This amount of water may include the water present in an added acid or combination of acids, for example aqueous phosphoric acid and or sulphuric acid, that is added to the liquid propylene glycol in order to acidify the propylene glycol. If desired, the method may also include the prior step of adding the desired quantities of water to the propylene glycol to achieve the required exothermic reaction and desired physical properties of the reaction product.

[0079] In this specification, the term “metal oxide” generally refers to oxides of Group 1A metals, Group 2A metals, transition metals and combinations thereof. A preferred metal oxide is calcium oxide. The metal oxide is typically in powder form and has a purity of at least 75% (w / w) and may for example include one or more metal oxides and hydroxides or carbonates as impurities. Various factors will affect the amount of calcium oxide required. These may include, amongst others, the purity and particle size of the calcium oxide, the reactivity of the calcium oxide, the amounts of other oxides or salts present in the calcium oxide and the amount of water present in the propylene glycol. The reactivity of the calcium oxide will be determined by the state of division of the calcium oxide particles, the purer and the more finely-divided the material, the more reactive it will be. The calcium oxide used in the method of the invention will typically have a purity above about 75% (w / w).

[0080] Preferably, the calcium oxide will be a fine powder with purity between about 85% and 100% (w / w) and more preferably between about 90% and 100% (w / w).

[0081] In order to control the exotherm produced when the metal oxide reacts with the acidified liquid propylene glycol, the metal oxide such as the calcium oxide may be combined with a metal hydroxide salt such as calcium hydroxide or magnesium hydroxide or metal carbonate salt such as calcium carbonate or magnesium carbonate. For example, the metal oxide may be combined with a predetermined amount of calcium hydroxide and / or calcium carbonate or other metal hydroxide or carbonate salt(s) in order to control the rate and / or magnitude of the exothermic reaction. The terms calcium oxide or metal oxides in the context of this specification accordingly include within their scope oxides containing hydroxides and / or carbonates i.e. the metal oxide may (optionally) contain a metal hydroxide and / or a metal carbonate.

[0082] Various factors will affect the amount of calcium oxide required. These may include, amongst others, the purity and particle size of the calcium oxide, the reactivity of the calcium oxide, the amounts of other oxides or salts present in the calcium oxide and the amount of water and / or acid present in the propylene glycol.

[0083] The method of the invention employs an accelerator or accelerators to drive the exothermic reaction. More particularly, the accelerator(s) can be a material which will react exothermically with a metal oxide and / or a metal hydroxide (where present) combined with propylene glycol to provide the heat to transform the propylene glycol into a solid product, with the propylene glycol either present as a spectator supported on the solid product or forming part of the new solid product or chemical entity.

[0084] The accelerator can be selected as required and in one embodiment the accelerator is an acidif ier to acidify the propylene glycol in order to achieve an exothermic reaction of sufficient intensity to generate a solid material. In one embodiment the propylene glycol is acidified with an acid or a salt of an acid. The acid can be, for example, an inorganic or an organic acid or a combination of acids. The inorganic acids may be selected from phosphoric acid, sulphuric acid and hydrochloric acid. Inorganic salts such as calcium hydroxide, calcium carbonate, calcium phosphates, calcium sulphate, magnesium hydroxide, magnesium carbonate, magnesium phosphate(s), magnesium sulphate or combinations of these may be included. The organic acids may be selected from amino acids for example methionine and / or lysine, amino acid analogues or amino acid derivatives for example methane hydroxy analogue (MHA), alkyl carboxylic acids, hydroxyalkyl carboxylic acids, lactic acid, propionic acid, fatty acids, salts of any of these and combinations of these. The fatty acids may for example be selected from short-, medium or long-chain saturated or unsaturated fatty acids for example palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid and combinations of these. The organic acid may be selected from methionine, methionine hydroxy analogue (MHA), lysine, salts of these and mixtures of these. The amount of acid required is determined by quantities and purities of the other ingredients so that the combination of ingredients achieve the required exothermic reaction.

[0085] Where phosphoric acid is used as an acidif ier in the method of the invention with either calcium oxide or a mixture of metal oxide(s) and metal hydroxide(s) with water and propylene glycol, the exotherm is generated through the reaction of the calcium oxide with water, but additionally also through the reaction of the inorganic acid with the oxide and / or hydroxide. In this case, the additional reaction (depending on reagent ratios) results in the formation of an inorganic metal salt such as calcium phosphate and / or dicalcium phosphate. In this case, the propylene glycol may also be supported on the inorganic salt matrix being generated as a carrier.

[0086] If an organic acid, such as palmitic acid, is for example used as an accelerator, the additional reaction is the formation of an organic metal salt such as an amino acid, amino acid analogue / derivative, alkyl carboxylic acids, hydroxyalkyl carboxylic acid, lactic acid, propionic acid, fatty acid salt or a combination thereof. For example, where palmitic acid is employed, calcium palmitate can form the solid component in the product and the propylene glycol may be supported on this solid component as a carrier. The propylene glycol may be present as an unreacted spectator supported on the solid organic salt or it may react at least partially with the organic acid depending on reagent ratios to form a mono- and / or di-ester.

[0087] The addition of any suitable accelerator which reacts with the metal oxide / hydroxide and / or propylene glycol in an exothermic manner to give a solid product in which the propylene glycol is present as a spectator and / or part of a new chemical entity which is supported on the solid product, is accordingly included within the scope of the invention.

[0088] The accelerator may be added in various amounts at any stage of the reaction depending on the desired outcome and as indicated above may be a substance or substances which would be highly reactive towards the calcium oxide or calcium hydroxide (where present) which forms in the reaction of the starting calcium oxide with water in the water-propylene glycol mixture and may or may not be reactive towards starting propylene glycol.

[0089] The amount of acid and water present will, in turn, determine the amount which will react with the calcium oxide and the amount of water that will be evaporated as a result of the exothermic reaction between the calcium oxide, the acid and the water. The amount of water driven off during the exothermic reaction will also be affected by various factors such as impurities in the water, the altitude above sea level, ambient temperature, temperature of the mixing vessel, heat losses from the system and the like.

[0090] Other additional feed components may be included in the method and feed materials of the invention as required. Any material which is compatible with the reaction conditions of the invention and which would be, or would produce, a suitable animal feedstuff material may be used as additional feed component(s). Accordingly, the invention allows for the manipulation or adjustment of the chemistry by the addition of an additive or mixture of additives to provide products of which the respective components meet specific requirements for its intended use, such as regulatory approval of individual components and / or nutritional value in animal nutrition applications or desired chemical and / or physical properties for intended applications The additional feed component may be selected from vitamins, minerals, trace elements, proteins, carbohydrates, oils, choline and choline salts, betaine and betaine salts, phospholipids / lecithins, metal salts, yeasts, flavouring agents, colouring agents or mixtures of these. The oils may be selected from plant-based oils rich in omega-3 and / or omega-6 fatty acids, olive oil, rapeseed oil, canola coil, palm oil, sunflower oil, linseed oil, flax seed oil, coconut oil, sunflower oil, soybean oil, fish oil and the like or combinations of these.

[0091] If desired, the propylene glycol in the method of the invention can be replaced in part by an alternate glucose precursor such as glycerol e.g. up to 50% by weight of the propylene glycol can be substituted by glycerol.

[0092] The method of the invention may thus be conducted in the presence of an accelerator and / or other additional feed components which will provide, for example, a phosphate, sulphate or chloride in the propylene glycol derived material, or an organic component such as an organic acid or salt thereof. The propylene glycol derived material will be suitable for use as an animal feedstuff or in an animal feedstuff.

[0093] Optionally, the accelerator and / or the additional feed component(s) may be added in a separate stream or streams during or after the reaction or combined with the starting material propylene glycol.

[0094] The method of the invention can be implemented in various ways as required. For example, the starting materials can be combined and mixed in any order or sequence using any type of equipment. The method may also be implemented as a batch process, continuous process, semi-batch process, semi-continuous process, manual, automated, semi-automated or any variation of these process types at any scale.

[0095] A portion of the product may also be recycled back into the reaction vessel on a continuous basis. The reaction vessel and / or the reaction mixture or starting materials may also optionally be heated for example when the reaction vessel is cold and / or the starting material(s) have been stored at a low temperature.

[0096] The process may include a step of flavouring and / or drying and / or heating and / or steaming and / or pelletising and / or other steps of further processing of the reaction product after the exothermic reaction is completed.

[0097] The solid product produced in the invention is a particulate or powdery material and may be an animal feedstuff in its own right or, optionally, is combined with other animal feedstuff components to act as a fortifying component or nutritional material in the animal feedstuff.

[0098] The invention will now be described by way of example only with reference to the following non-limiting Examples:

[0099] Examples

[0100] General Method:

[0101] Propylene glycol (99.9%) liquid, water and either phosphoric acid (H3PO4, 85%, aq) or sulphuric acid (H2SO4, 98%) were placed into a 100 ml container, the liquids mixed with a metal temperature probe and the temperature of the respective liquid mixtures recorded. Reactivity-tested, pre-weighed calcium oxide (94%) powder was added quickly in a single lot to the liquid mixture in each experiment, the resultant mixtures mixed thoroughly and quickly and then left to react. The temperatures of the mixtures were recorded every 30 seconds and the maximum reaction temperature at each corresponding reaction time recorded. After the maximum temperature has been reached in each reaction, the temperature probe was used to mix the reaction products. In the cases where powdery products were formed, the powders were transferred to storage containers, the product weights recorded and the physical appearance of the respective products noted. It was found that the addition of an acid such as phosphoric acid (H3PO4, 85%, aq) or sulphuric acid (H2SO4, 98%) to propylene glycol-water mixture starting materials in suitable ratios provided fast and potent exothermic reactions with calcium oxide to enable the conversion of propylene glycol liquid into powdery materials in the case of the examples shown in Table 1 , which summarises the details and observations of the series of experiments with propylene glycol, which gave particulate products such as powders, flours, granules and the like.

[0102] Table 1 Experiments with propylene glycol-water mixtures, phosphoric acid and calcium oxide as starting materials.

[0103] * Calcium oxide (CaO): 94.0%, calcium carbonate (CaCOs): 3.9%, magnesium oxide (MgO): 0.5%, silicone oxide (SiCh): 0.8%, aluminium oxide (AI2O3): 0.8%, calcium sulphate (CaSO4): 0.05%.

[0104] Additional experiments were subsequently done with the addition of L-lysine powder and / or methionine hydroxy analogue (calcium salt) powder or DL-methionine powder to propylene glycol-water-phosphoric acid mixtures prior to the addition of calcium oxide powder. The same general procedure was followed as described for the PG PHOS experiments shown in Table 1 , except for the addition of the additional feed component powders to the propylene glycol-water-phosphoric acid liquid mixtures to form suspensions which were mixed before the addition of the calcium oxide powder in each experiment.

[0105] The results of the experiments wherein free-flowing powders or flours were obtained are summarised in Table 2. Table 2

[0106] Experiments with propylene glycol-water mixtures, phosphoric acid and L-lysine and / or methionine hydroxy analogue, calcium salt (Ca-MHA) or DL-methionine and calcium oxide as starting materials.

[0107] * Calcium oxide (CaO): 94.0%, calcium carbonate (CaCOs): 3.9%, magnesium oxide (MgO): 0.5%, silicone oxide (SiCh): 0.8%, aluminium oxide (AI2O3): 0.8%, calcium sulphate (CaSO4): 0.05%.

[0108] Additional small-scale experiments were done with the aim to identify optimal starting material ratio(s) as examples based on the selected starting materials shown in Table 3 which resulted in the formation of particulate propylene plus glycerol-based combination products.

[0109] The same general procedure was followed as described for the PG PHOS experiments summarised in Table 1 , with liquid mixtures of propylene glycol and animal feed grade glycerol (as opposed to propylene glycol alone) used as starting materials together with phosphoric acid and calcium oxide.

[0110] The results of the experiments in this group, wherein free-flowing powders or flours were obtained, are summarised in Table 3.

[0111] Table 3

[0112] Experiments with propylene glvcol-glvcerol-water mixtures, phosphoric acid and calcium oxide as starting materials. * Calcium oxide (CaO): 94.0%, calcium carbonate (CaCOs): 3.9%, magnesium oxide (MgO): 0.5%, silicone oxide (SiCh): 0.8%, aluminium oxide (AI2O3): 0.8%, calcium sulphate (CaSO4): 0.05%.

[0113] ** Technical / Animal feed grade glycerine, glycerol: 83.5%, water: 12.1 %, a dark yellow, viscous liquid.

[0114] Additional small-scale experiments were subsequently done with the addition of either lysine or methionine hydroxy analogue (calcium salt) or both powders to propylene glycol-glycerol-water-phosphoric acid mixtures prior to the addition of calcium oxide powder. The same general procedure was followed as described for the PG PHOS experiments shown in Table 1 , except for the addition of the additional feed component powders to the propylene glycol-glycerol-water-phosphoric acid liquid mixtures to form suspensions which were mixed before the addition of the calcium oxide powder in each experiment.

[0115] The results of the experiments wherein free-flowing powders or flours were obtained are summarised in Table 4.

[0116] Table 4

[0117] Experiments with propylene glvcol-glvcerol-water mixtures, phosphoric acid and L- lysine and / or methionine hydroxy analogue, calcium salt (Ca-MHA) and calcium oxide as starting materials.

[0118] * Calcium oxide (CaO): 94.0%, calcium carbonate (CaCOs): 3.9%, magnesium oxide (MgO): 0.5%, silicone oxide (SiCh): 0.8%, aluminium oxide (AI2O3): 0.8%, calcium sulphate (CaSO4): 0.05%. ** Technical / Animal feed grade glycerine, glycerol: 83.5%, water: 12.1 %, a dark yellow, viscous liquid.

[0119] As indicated above, acids (inorganic and / or organic) other than phosphoric acid or sulphuric acid can be used as acidifying agents to provide the corresponding calcium salts of these acids with or without additional feed components such as amino acids, etc. included in the formulations. Equivalents

[0120] The foregoing description details presently preferred embodiments of the present invention. Numerous modifications and variations in practice thereof are expected to occur to those skilled in the art upon consideration of these descriptions. Those modifications and variations are intended to be encompassed within the claims appended hereto.

Claims

Claims1. A method of producing a solid metal-stabilised propylene glycol derived material comprising: combining propylene glycol with a metal oxide, and an accelerator, the propylene glycol having a water content of up to about 50% by weight, and creating an exothermic reaction to transform the liquid propylene glycol into a solid propylene glycol derived material.

2. A method as claimed in Claim 1 , wherein the metal oxide is selected from Group 1A metal oxides, Group 2A metal oxides, transition metal oxides and combinations thereof.

3. A method as claimed in Claim 1 or Claim 2, wherein the metal oxide optionally contains a metal hydroxide and / or a metal carbonate.

4. A method as claimed in any one of the preceding claims, wherein the metal oxide is calcium oxide.

5. A method as claimed in Claim 4, wherein the calcium oxide has a purity of at least about 75%.

6. A method as claimed in any one of the preceding claims, wherein the accelerator comprises a propylene glycol acidifier.

7. A method as claimed in Claim 6, wherein the acidifier is selected from the group comprising an inorganic acid or salt, and / or an organic acid or salt, and / or a combination thereof.

8. A method as claimed in Claim 7, wherein the inorganic acid is selected from phosphoric acid, sulphuric acid, hydrochloric acid and / or a combination thereof and / or the organic acid is selected from the group comprising amino acids which can include methionine and / or lysine, amino acid analogues oramino acid derivatives which can include methionine hydroxy analogue (MHA), alkyl carboxylic acids, hydroxyalkyl carboxylic acids, lactic acid, propionic acid, fatty acids, salts thereof and / or a combination thereof.

9. A method as claimed in Claim 8, wherein the inorganic acid is a fatty acid and is a short, medium or long-chain saturated or unsaturated fatty acid or a mixture thereof.

10. A method as claimed in Claim 9, wherein the fatty acid is selected from the group comprising palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid and / or a combination thereof.

11. A method as claimed in any one of Claims 1 to 10, further comprising the step of combining an additional feed component selectable from the group comprising vitamins, minerals, trace elements, proteins, carbohydrates, oils, choline and choline salts, betaine and betaine salts, phospholipids / lecithins, metal salts, yeasts, flavouring agents, colouring agents or a combination thereof with the propylene glycol, the metal oxide and the accelerator.

12. A method as claimed in any one of Claims 1 to 11 , wherein the propylene glycol is partially substituted by glycerol.

13. A method of as claimed in Claim 12, wherein up to 50% by weight of propylene glycol is substituted by glycerol.

14. A method as claimed in any one of the preceding claims, wherein the acidifier is an acid and the metal oxide is calcium oxide and wherein the method produces a calcium salt of propylene glycol in the form of a solid, calcium-stabilised, propylene glycol-derived product.

15. A solid metal-stabilised propylene glycol derived material comprising: from about 20% to about 80% by weight propylene glycol, and from about 5% to about 40% by weight a metal or combination of metals.

16. A solid metal-stabilised propylene glycol derived material as claimed in Claim 15, wherein the metal is part of an inorganic and / or an organic metal salt.

17. A solid metal-stabilised propylene glycol derived material as claimed in Claim 15 or Claim 16, wherein the metal in the metal salt comprises a Group 1 A, a Group 2A or a transition metal or a combination thereof.

18. A solid metal-stabilised propylene glycol derived material as claimed in Claim 16 or Claim 17, wherein the inorganic metal salt comprises a phosphate, sulphate, or chloride metal salt or a combination thereof.

19. A solid metal-stabilised propylene glycol derived material as claimed in any one of Claims 15 to 18, wherein the organic metal salt comprises the metal salt or metal salts of an amino acid which can include methionine and / or lysine, an amino acid analogue / derivative which can include methionine hydroxy analogue (MHA), alkyl carboxylic acid, hydroxyalkyl carboxylic acid, lactic acid, propionic acid, fatty acid, or a combination thereof.

20. A solid metal-stabilised propylene glycol derived material as claimed in any one of Claims 15 to 19, further comprising an additional feed component selectable from the group comprising vitamins, minerals, trace elements, proteins, carbohydrates, oils, choline and choline salts, betaine and betaine salts, phospholipids / lecithins, metal salts, yeasts, flavouring agents, colouring agents or a combination thereof.21 . A solid metal-stabilised propylene glycol derived material as claimed in any one of Claims 15 to 20, wherein the propylene glycol is partially substituted with glycerol.

22. An animal feed composition comprising a metal-stabilised solid propylene glycol derived material as claimed in any one of Claims 15 to 21.

23. The animal feed composition of Claim 22, which is a particular feed composition.

24. The animal feed composition of Claim 23, which is a powder, a flour or granules.

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