WO1994028732A1

WO1994028732A1 - Reduction of moisture loss from plant and animal matter

Info

Publication number: WO1994028732A1
Application number: PCT/AU1994/000304
Authority: WO
Inventors: Frederick John Meeker
Original assignee: Ici Australia Operations Proprietary Limited
Priority date: 1993-06-07
Filing date: 1994-06-07
Publication date: 1994-12-22

Abstract

A composition and process for manufacture of a composition for the reduction of moisture loss from plant or animal matter comprising an oil-in-water emulsion comprising water, at least one emulsifier and an oil component comprising at least one fatty acid ester, fatty alcohol or their derivatives.

Description

REDUCTION OF MOISTURE LOSS FROM PLANT AND ANIMAL MATTER

The present invention relates to compositions and processes for improvement of the reduction of moisture loss from plant and animal matter such as agricultural produce and meat.

Agricultural produce such as flowers, fruit, nuts and vegetables have limited storage life following harvest - their rate of deterioration being greatly influenced by loss of moisture from cells and flesh or pulp. Similarly, the cells and flesh of animals are adversely affected by moisture loss. Moisture loss is a particular problem in the meat industry where it has deleterious effects on the weight, texture and appearance of the carcasses.

For many decades it has been a statutory requirement of the meat industry that carcasses be stored at low temperature to inhibit the growth of bacteria and micro-organisms on the meat. Freshly slaughtered cattle or sheep or the like are hung then cleaned and the carcass either stored whole or split into halves prior to storage in the chiller. Some animals such as pigs are not skinned and the carcass left whole during storage.

The carcasses may be transported in refrigerated vans from the abattoir to local customers such as meat distributors and butchers or alternatively broken down into primals prior to shipment to local domestic or export markets.

It is well known in the meat industry that while chilling of a carcass is mandatory, it causes deterioration of meat. Moisture loss in the dry atmosphere of a chiller is reflected in weight loss of the carcass and because meat is generally sold on a weight basis, loss of carcass weight can be equated to a decrease in its value.

The moisture loss promotes discolouration and hardening of meat and fat tissues and this deterioration in texture and appearance of a carcass tends to make it generally less attractive to potential purchasers. Loss of moisture from the carcass persists as long as it is chilled but is most acute in the first twenty-four hours of chilling even under the most carefully controlled chilling conditions. Weight losses have been recorded of up to 3% in beef sides, 2% in lambs and 2.5% in pigs.

It has now been found that a reduction in the amount of moisture lost from carcasses can be provided by the application of an oil-in-water emulsion that is capable of being quickly sprayed onto carcasses before they are passed into a chiller.

The present invention therefore provides a composition for the reduction of moisture loss from plant and animal matter comprising an oil-in-water emulsion comprising water, a component comprising at least one emulsifier and an oil component comprising at least one fatty acid ester, fatty alcohol or their derivatives, wherein the emulsifier: oil component ratio is between 0.001 :10 and 10:1.

Where used herein the term oil-in-water emulsion includes emulsions wherein the discontinuous phase comprises at least one oil or at least one wax or a mixture of oil and wax.

Where used herein the term fatty acid esters, fatty alcohols or their derivatives includes esters of fatty acids, esters of fatty acids with glycerol or with mixed glycerides and fatty acid esters with monohydric fatty alcohols and mixtures thereof. These include natural waxes such as esters of hydroxylated unsaturated fatty acids, wool-wax and beeswax which may include naturally occurring straight chain acid emulsifiers. In a preferred embodiment the oil component of the composition of the current invention is chosen from the group comprised of cetyl stearyl alcohol, glycerol monostearate, monoglycerides, oleic acid, palmitic acid and stearic acid and mixtures thereof. Said oil may additionally function as an emulsifier, and may be pH modified. Cetyl stearyl alcohol is sold commercially as a mixture of cetyl alcohols and stearyl alcohols in defined proportions. Any commercially available cetyl stearyl alcohol is suitable for the composition of the current invention including the mixtures sold under the Trade Mark "HYDRANOL" (Trade Mark of Henkel GmBh).

Emulsifiers suitable for use in the compositon of the current invention include those from the Australian Food Standards Code, Group 4 emulsifiers, and any other emulsifiers known to those skilled in the art including those suitable for use in the formation of oil-in-water emulsions such as sodium lauryl sulphate salts of fatty acids, sucrose esters, TWEEN series emulsifiers, and natural emuisifers. (TWEEN is a trade mark of ICI Americas).

In use the composition may be diluted to a solution of convenient concentration, preferably with water. The optimal amount of dilution will depend on the nature and proportion of active components in the concentrate but the preferred ratio of emulsion:diluent is between 1:1 and 1 :30. If the proportion of actives in the concentrate is too high, the meat on which it is sprayed tends to have a soapy, slippery feel and slimey appearance; while the composition will still be effective in preventing moisture loss from the meat, consumers tend to reject meat which has what they perceive to be unpleasant appearance or feel.

Without wishing to be bound by theory it is suggested that the microscopic structure of the oil-in-water emulsion is important to the prevention of moisture loss from meat to which the product is applied. Amongst other factors, the structure and viscosity of an oil-in-water emulsion is related to its formulation and production method, including the specific formulation used, the processing temperature, the dispersion rate and the degree of refinement imposed by shear and mixing. It has been found that if insufficient refinement is applied to components of the composition of the current invention, an emulsion will not form. Conversely, if excessive refinement is applied to an oil-in-water emulsion of the current invention once it has formed it starts to exhibit non-Newtonian behaviour and may either partially or fully invert to a water-in-oil type emulsion or simply break to form an oil, wax and water mixture.

Emulsions which exhibit non-Newtonian characteristics are often difficult to dilute with water. In a preferred embodiment the oil-in-water emulsion of the current invention exhibits Newtonian characteristics.

Excessive refinement of the oil-in-water emulsion of the current invention may cause the viscosity of the emulsion to increase to an extent that the composition cannot be poured and is thus difficult to handle and dilute. In a preferred embodiment the viscosity of the oil-in-water emulsion of the the current invention is between 0.002 and 0.060 Pascal. In a particularly preferred embodiment the viscosity is between 0.025 and 0.30 Pascal.

The microscopic structure of the oil-in-water emulsion of the current invention can be observed by use of a microscope or similar optical instrument. In a preferred embodiment, the oil-in-water emulsion of the current invention comprises oil droplets, of which greater than 75% are between 0.2 micron and 3.2 micron in diameter. In a particularly preferred embodiment greater than 80% or droplets are between 0.5 micron and 1.0 micron in diameter.

It has been found that certain types and degrees of refinement tend to cause the oil droplets to clump together. In a preferred embodiment the majority of oil droplets are not clumped with other droplets and those clumps which do form are less than 3.5 micron diameter.

As abattoirs routinely process numerous carcasses per day as quickly as possible, it is important that the composition of the current invention can be quickly and efficiently applied to the surface of meat. In many abattoirs fresh carcasses are often hung on a moving chain and it is necessary to be able to apply the composition in the time it takes for the chain to move the carcass from the cleaning room/area to the chiller.

As hand spraying or automatic spraying are the most convenient and most economical methods of applying material to carcasses it is preferable that the composition of the current invention can be applied to meat using ordinary industrial spraying equipment. It is preferable that the composition of the current invention is suitably fluid and dispersible to be diluted with water. Preferably the viscosity and rheology of the composition, after dilution, is suitable for application of the composition to meat by spraying.

The present invention further provides a process for making the composition of the current invention, the process comprising the steps of;

mixing together the component comprising at least one emulsifier and at least one fatty acid ester, fatty alcohol or their derivatives at a temperature between 50 and 150°C, - adding said mixture to an initial proportion of the water at elevated temperature, such that the average temperature of the mixture remains between 50 and 100°C, refining the diluted mixture at high shear to form an oil-in-water pre- emulsion - pumping the oil-in-water pre-emulsion into the remaining water shearing and mixing the pre-emulsion and water to form an oil-in-water emulsion.

The initial proportion of water may be between 10 and 100% of the total water to be added to form the oil-in-water emulsion. Where all of the water is added the process for making the composition of the current invention comprises the steps of; mixing together the component comprising at least one emulsifier and at least one fatty acid ester, fatty alcohol or their derivatives at a temperature between 50 and 150°C, adding said mixture to the water at elevated temperature, such that the average temperature of the mixture remains between 50 and 100°C, refining the diluted mixture at high shear to form an oil-in-water emulsion pumping the oil-in-water pre-emulsion through a heat exchanger to cool it to ambient temperature.

Where solid constituents exist in the component comprising at least one emulsifier and at least one fatty acid ester, fatty alcohol or their derivatives liquids the constituents should be mixed together at a temperature above the highest melting point of any solids. When this mixture is added to an initial proportion of water, the average temperature of the mixture should remain above the highest melting point of any constituent.

The oil-in-water emulsion thus formed may then be diluted by adding a diluent, preferably water.

In a particularly preferred embodiment the process for making the composition of the current invention comprises the steps of;

heating cetyl stearyl alcohol and emulsifier to between 90 and 150°C and mixing, pumping the mixture into an initial proportion of the water at a temperature between 70 and 100°C, refining the mixture in a colloid mill, homogeniser or other mixer capable of producing shear for between 1 and 30 mins to form an oil-in-water pre-emulsion, and adding said pre-emulsion to the remaining proportion of water at a temperature of between -2 and 30°C and continuting to mix with shear until a homogeneous emulsion is formed. Variations in the method of preparation of the composition of the current invention will be apparent to those skilled in the art, such as the addition of water to the pre-emulsion rather than adding pre-emulsion to water.

The present invention further provides a process for the treatment of plant or animal matter with the composition of the current invention comprising diluting the composition then applying the dilute solution to plant or animal matter. In a preferred embodiment the application is carried out by spraying or brushing, or alternatively dipping or soaking the plant or animal matter in the dilute solution.

While the invention has been demonstrated as effective in reducing moisture loss from the meat of pigs, cows and sheep it will readily apparent that the invention will have ready applicability to other meat types including rabbit, deer, birds, poultry, fish and soforth. It is also apparent that the invention has applicability to the mortuary industry where reduction of moisture loss from cadavers is important where the appearance of a corpse must be maintained for an extended period of time.

The invention has also proved effective in reducing moisture loss from vegetables, fruit, nuts such as chesnuts, pulses, cut flowers and plants.

While the invention has been explained in relation to its preferred embodiments it is to be understood that various modifications thereof will become apparent to those skilled in the art upon reading the specification. Therefore, it is to be understood that the invention disclosed herein is intended to cover such modifications as fall within the scope of the appended claims.

The invention is further described with reference to the following non-limiting examples. EXAMPLE 1

50 kilograms of solid Hydranol was added to 50 kilograms of TWEEN-60 emulsifier and heated to 120°C to melt the Hydranol-D so that the two components could be thoroughly mixed. (TWEEN is a trade mark of ICI Americas.) The mixture formed was kept at 120°C and pumped into an insulated tank holding 300 kilograms of water at a temperature of 78°C. On combination the mixture of Hydranol, TWEEN-60 had a temperature of around 87°C and was maintained at this temperature whilst refined in a colloid mill at high shear rates for 20 mins to form an oil-in-water pre-emulsion. The pre- emulsion at around 87°C was added to the remaining 600 kilograms of water at ambient temperature and mixed thoroughly.

For application to carcasses, the oil-in-water emulsion so formed was diluted by 10 times its volume with water.

EXAMPLE 2 Thirty carcasses of freshly slaughtered beef were skinned, cleaned and hung before being sprayed with the dilute composition of Example 1. The carcasses were then weighed and stored in a chiller for 24 hours at 3°C , then re- weighed.

COMPARATIVE EXAMPLE 1 Thirty carcasses of freshly slaughtered beef were skinned, cleaned and hung before being weighed and stored in a chiller for 24 hours at 3°C, then re- weighed. The weights of the untreated carcasses were compared with the weights of the treated carcasses of Example 2 and the results recorded in Table 1.

It can be seen that the treated beef carcasses lost on average 0.9% less weight than untreated carcasses of beef. Furthermore the treated beef retained much more of its red colour than the untreated beef. The untreated beef showed surface drying, darkening of the meat and yellowing of the fat.

EXAMPLE 3 Thirty freshly slaughtered pig carcasses were cleaned and hung before being sprayed with the composition of Example 1. The carcasses were then weighed and stored in a chiller for 24 hours at 3°C, then re-weighed.

COMPARATIVE EXAMPLE 2

Thirty freshly slaughtered pig carcasses were cleaned and hung before being weighed and stored in a chiller for 24 hours at 3°C, then re-weighed.

The weights of the untreated carcasses were compared with the weights of the treated carcasses of Example 3 and the results recorded in Table 1.

It can be seen that the treated pig carcasses sides lost on average 0.7% less weight than untreated carcasses.

TABLE 1

BEEF PORK Treated Untreated Treated Untreated

Average Carcass Weight

(before chilling) 200 kg 200 kg 65 kg 65 kg

Average Percentage Weight

Loss (after chilling) 1.5% 2.4% 0.7% 1.4%

Claims

The claims defining the invention are as follows;

1. An oil-in-water emulsion composition for the reduction of moisture loss from plant or animal matter comprising an oil-in-water emulsion comprising water, a component comprising at least one emulsifier and an oil component comprising at least one fatty acid ester, fatty alcohol or their derivatives, wherein the emulsifier: oil components ratio is between 0.001 :10 and 10:1.

2. An oil-in-water emulsion composition according to claim 1 which exhibits Newtonian characteristics.

3. An oil-in-water emulsion composition according to any of the preceeding claims wherein said oil-in-water emulsion comprises oil droplets of which greater than 75% of droplets are between 0.2 micron and 3.2 micron in diameter.

4. An oil-in-water emulsion composition according to any of the preceeding claims wherein the emulsion viscosity is between 0.002 and 0.060 Pascal.

5. An oil-in-water emulsion composition according to any of the preceding claims wherein said fatty acid ester, fatty alcohols or their derivatives are chosen from the group comprising esters of fatty acids, esters of fatty acids with glycerol or with mixed glycerides and fatty acid esters with monohydric fatty alcohols and any mixtures thereof.

6. An oil-in-water emulsion composition according to claim 5 wherein said fatty acid ester, fatty alcohol or their derivatives are chosen from the group comprising natural waxes, wool-wax and beeswax.

7. An oil-in-water emulsion composition according to any of the preceding claims wherein said oil component is chosen from the group comprising cetyl steryl alcohol, glycerol monostearate, monoglycerides, oleic acid, palmitic acid, stearic acid and mixtures thereof.

8. An oil-in-water emulsion composition according to claim 7 wherein said oil component additionally functions as an emulsifier.

9. An oil-in-water emulsion composition according to any of the preceding claims wherein said emulsifier is chosen from the group comprising sodium lauryl sulphate, salts of fatty acids, sucrose esters and natural emulsifiers.

10. A dilute solution comprising an oil-in-water emulsion composition according to any of the preceding claims said solution having an emulsion: diluent ratio of between 1 :1 and 1 :30.

11. A process for manufacture of the oil-in-water emulsion composition of claims 1 to 10 wherein said process comprising the steps of:

mixing together the component comprising at least one emulsifier and at least one fatty acid ester, fatty alcohol or their derivatives at a temperature between 50 and 150°C, adding said mixture to an initial proportion of the water at elevated temperature, such that the average temperature of the mixture remains between 50 and 100°C, refining the diluted mixture at high shear to form an oil-in-water pre- emulsion pumping the oil-in-water pre-emulsion into the remaining water and shearing and mixing the pre-emulsion and water to form an oil-in-water emulsion.

12. A process according to claim 11 wherein said initial proportion of water is between 10 and 100% of the total water added to form said oil-in-water emulsion composition.

13. A process for manufacture of the oil-in-water emulsion composition of Claims 1 to 10 comprising the steps of: mixing together the component comprising at least one emulsifier and at least one fatty acid ester, fatty alcohol or their derivatives at a temperature between 50 and 150°C, adding said mixture to water at elevated temperature, such that the average temperature of the mixture remains between 50 and 100°C, refining the diluted mixture at high shear to form an oil-in-water emulsion and pumping the oil-in-water pre-emulsion through a heat exchanger to cool it to ambient temperature.

14. A process for manufacture of an oil-in-water emulsion composition for the reduction of moisture loss from plant or animal matter comprising the steps of: heating cetyl stearyl alcohol and emulsifier to between 90 and 150°C and mixing, pumping the mixture into an initial proportion of the water at a temperature between 70 and 100°C, refining the mixture in a colloid mill, homogeniser or other mixer capable of producing shear for between 1 and 30 mins to form an oil-in-water pre-emulsion, and adding said pre-emulsion to the remaining proportion of water at a temperature of between -2 and 30°C and continuing to mix with shear until a homogeneous emulsion is formed.

15. A process for the treatment of plant or animal matter with the composition of the current invention comprising diluting said composition then applying it to said plant or animal matter.

16. A process for the treatment of plant and animal matter with a composition for reducing moisture loss substantially as described herein with reference to the examples.

17. A composition substantially as described herein with reference to the examples.

18. A process for the manufacture of an oil-in-water emulsion composition for the reduction of moisture loss substantially as described herein with reference to the examples.