AU2003283889B2 - Pet food flavouring agent containing fish processing waste - Google Patents

Description

WO 2004/047555 PCT/NZ2003/000258 1 PET FOOD FLAVOURING AGENT CONTAINING FISH PROCESSING WASTE FIELD OF THE INVENTION The invention relates to the field of commercial pet food manufacture. In particular it relates to a flavouring agent for commercial pet foods that is obtained from processing of wastewater from commercial fish canning operations.

BACKGROUND OF THE INVENTION A challenge to the manufacturers of commercial pet mammal foods continues to be to provide products that have superior palatability. There exists a particular challenge to provide highly palatable dry packeted pet foods that are based primarily on cereals. However, in many instances, raw materials that are known to enhance palatability of pet foods are too expensive to be commercially feasible inclusions in such pet foods. Therefore, the commercial pet food manufacturer must identify low-cost palatability enhancing materials that are suitable for inclusion in such products.

Pet mammals, particularly cats, are known to regard fish-based materials as highly palatable. However, many of the fish-based materials available from this industry which do possess these properties are too expensive for inclusion in commercial pet food recipes. In addition, those waste or reject materials which may feasibly be included in commercial pet foods due to their low cost, nevertheless tend not to contribute anything of value to the palatability of the foods, usually due to the harsh or uncontrolled conditions under which they are collected.

In the fish canning industry, large amounts of water are used in various stages of the fish processing operation. For example, in tuna processing, before the process of trimming, the whole tuna is steamed to enable easy separation of the red and white meat from the tuna frame. The water used in this steaming process tends to condense on the fish material and so tends to absorb many soluble chemicals that are associated with the fish meat. The condensate from the steaming process is collected and various processes may be used to remove the solids from the water, in order to reduce the BOD load in the water, thereby reducing the cost of further treatment of the wastewater.

WO 2004/047555 PCT/NZ2003/000258 2 Such waste water is commonly known in the art as 'cook water'. For ease of reference, where the phrase 'cook water' is used in this document, it refers to the waste water streams emanating from commercial fish canning operations as described above.

One such manner of treatment is disclosed in US Patent Document No.

4,282,256 by Evich et al ('Evich'). In that document, waste water solids from a tuna canning operation are concentrated by flotation of the oils and proteins in the water as sludge. The sludge is dewatered, blended with a solid carrier and dried.

While this document suggests the use of this material as an additive in animal foods, it will be clear to those skilled in the art that both the drying operation and the need to include such a material in the bulk of extruded material, if used in commercial packeted pet foods, would reduce the potential palatability benefits of such material.

Similar comments apply to the contents of US Patent Document No.

4,966,713, by Keys et al. This document discloses a similar water treatment process to that of Evich, and again suggests that the recovered solids that have been dried or cooked might be incorporated in animal feed. Generally speaking, both of these documents tend to suggest the use of recovered materials in animal feed as a more or less a convenient 'disposal' of the solids. They do not display an appreciation of the specialised nature of product flavour development that is undertaken for commercial pet foods. Therefore, these documents do not contribute to the skilled person's search for a commercially viable pet food palatability-enhancer.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a flavourenhancing agent for commercial packeted pet foods that is derived from fish material and is of relatively low cost.

According to one aspect of the invention, there is provided a sprayable flavour-enhancing agent for packeted pet mammal foods that incorporates cook water from commercial fish processing operations that has been concentrated by evaporation. It has surprisingly been found that this material is highly palatable to pet mammals and significantly enhances the overall palatability of commercial packeted pet foods.

WO 2004/047555 PCT/NZ2003/000258 3 The advantage of the evaporation process is that the flavoursome compounds in the water are not destroyed as they are likely to be in the prior art methods. Also, as these compounds are delivered in a liquid form, it is possible to apply them to the extruded pet food kibbles as a liquid spray, obviating the need for the flavour compounds to pass through the potentially harsh conditions of the extruder. Equally, avoidance of a drying step, as required in the prior art methods, reduces denaturation of the flavouring material prior to its application onto the pet food kibbles.

Preferably, the cook water emanates from tuna canning operations, as this material has been found to perform particularly well in achieving the flavour enhancing function. Notwithstanding this preference, similar wastewater streams from processing operations for other types of fish may, of course, be contemplated.

Advantageously, the cook water is evaporated to between 60% and solids on a mass basis. The preferred method of manufacture of the cook water is to evaporate the cook water from its initial solids content of approximately 5% by mass to approximately 65% by mass. It is preferably applied to the pet food kibble at a mass rate of between 2.5% 10% based on kibble mass.

The product may be added on its own or in conjunction with other flavour enhancing spray material. In a particularly preferred embodiment, a flavour enhancing spray for dry pet food is prepared by blending evaporated tuna cook water, having about 65% solids by mass, with water, phosphoric acid and optionally a reducing sugar. Other ingredients, such as commercial antioxidant blends, may optionally be included to improve the floor life of the spray.

In another aspect, the invention provides a palatable commercial packeted pet food product incorporating a flavour-enhancing spray coating that is at least partially derived from concentrated cook water from commercial fish canning operations.

In a further aspect, the invention provides a means for increasing the palatability of commercial packeted pet food products that includes incorporating in those products a flavour-enhancing spray that is at least partially derived from concentrated cook water from commercial fish canning operations.

WO 2004/047555 PCT/NZ2003/000258 4 In a further aspect, the invention provides a method of preparing a flavourenhancing spray for packeted pet mammal foods A method for preparing a flavour-enhancing spray coating for commercial packeted pet food products, said method including the steps of; concentrating cook water from commercial fish processing operations via evaporation to a solids content of between about and about 70% by mass, preferably about 65% by mass; and spraying said concentrated cook water on to the surface of said pet food products.

Preferably, the evaporation is carried out as a two-stage operation, and advantageously the first evaporation stage is carried out at a temperature of about 1000C and wherein the second evaporation stage is carried out in the temperature range of between about 60 0 C and about 800C. These relatively lowtemperature operations assist in preventing degradation of the desirable flavour compounds in the cook water.

The nature of the invention will be further explained using a specific, nonlimiting example of a palatable pet food product incorporating a flavour-enhancing agent according to the invention.

BRIEF DESCRIPTION OF THE FIGURE Figure 1 is a schematic flow diagram of a process for the preparation of concentrated tuna cannery cook water according to the invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT EXAMPLE 1 COMMERCIAL PACKETED FOOD FOR CATS A commercial packeted pet food for cats was prepared via ingredient blending and food extrusion processes well known in the art. Concentrated tuna cannery cook water, at approximately 65% solids by mass) was prepared and incorporated in the extruded kibble as part of a flavour-enhancing spray. The concentrated tuna cannery cook water was obtained from the International Seafood Associate Co. Ltd. in Thailand. A typical process for the preparation of concentrated tuna cannery cook water is shown in Figure 1.

The tuna cook water was blended to form a spray according to the formulation in Table 1.

WO 2004/047555 PCT/NZ2003/000258 Table 1.

Ingredient mass Concentrated Tuna Cook Water 43.3 (approx. 65% solids by mass) Water 43.3 Phosphoric Acid 12.0 Termox 1.10 (a commercially available antioxidant) Reducing sugar 0.9 Potassium Sorbate 0.28 This liquid spray was then applied to a commercial dry cat food kibble at a rate of 7% by mass. The formulation details of the product with the tuna cook water added and the standard product are indicated below in Table 2.

Table 2.

Ingredient Standard Product Product Incorporating (mass Tuna Cook Water (mass Cereal 73.7 68.5 Protein Meal 21.5 Fat 3.2 Vitamins Minerals 1.04 0.98 Stabilisers 0.56 0.52 Tuna Cook Water Spray NIL Both food products were offered to a panel of 179 cats. Each animal was offered 60g of product per day for 5 days. The cats' response to the offer was recorded. The overall percentage of each offering where the entire offering was actually consumed by the animal Ate All), and the cat owner's perception of how much the animal enjoyed consuming the food rated on a scale of 1 to 100 (Enjoyment), is presented below in Table 3.

WO 2004/047555 PCT/NZ2003/000258 6 Table 3.

Formulation Ate All Enjoyment Standard Product 38 69 Std Tuna Cook 44 73 Water Spray The results underwent statistical analysis via an ANOVA model with post hoc comparison. The above results indicate that the product containing tuna cook water was consumed at higher volumes than the standard product, and that the animals appeared to enjoy consuming the product containing tuna cook water significantly more than the standard product. This is a clear indication of the palatability enhancing effect of the flavour-enhancing spray based on the tuna cook water.

EXAMPLE 2 COMMERCIAL PACKETED FOOD FOR CATS The tuna cook water as described above was again blended to form a spray according to the formulation in Table 4.

Table 4.

Ingredient mass Concentrated Tuna Cook Water 43.3 (approx. 65% solids) Water 43.3 Phosphoric Acid 12.0 Termox 1.10 (commercially available antioxidant) Reducing sugar 0.9 Potassium Sorbate 0.28 This liquid spray was then applied to a commercial dry cat food kibble at a rate of 7% by mass. The formulation details of the product with the tuna cook water added and the standard product are indicated below in Table 5, along with the formulation of a commercial pet food having applied to it a flavouring spray prepared from a chicken viscera-based digest, of the kind well-known in the art as a flavouring agent for commercial pet foods.

WO 2004/047555 PCT/NZ2003/000258 Table Ingredient Standard Product Product Including Product Including (mass Chicken Based Tuna Cook Water Digest (mass (mass Cereal 73.7 68.5 68.5 Protein Meal 21.5 20 Fat 3.2 3.0 Vitamins Minerals 1.04 0.98 0.98 Stabilisers 0.56 0.52 0.52 Chicken Viscera NIL 7.0 NIL Digest Tuna Cook Water NIL NIL Spray All products were again offered to a panel of 179 cats. Each animal was offered 60g of product per day for 5 days. The cats' response to the offer was recorded. The overall percentage of each offering where the entire offering was actually consumed by the animal Ate All), the number of offerings where less than 5% was consumed Refusals), the percentage of the offering that was actually consumed Eaten) and the cat owner's perception of how much the animal enjoyed consuming the food rated on a scale of 1 to 100 (Enjoyment), is presented below in Table 6.

Table 6.

Formulation Ate All Refusals Eaten Enjoyment Standard Product 32 4 41 Std Chicken 40 1 46 72 Viscera Digest Std Tuna Cook 40 1 46 Water Spray The results underwent statistical analysis via an ANOVA model with post hoc comparison. The above results indicate that the product containing tuna cook water was consumed at higher volumes than the standard product, and that the animals appeared to enjoy consuming the product containing tuna cook water significantly more than the standard product. This is a clear indication of the WO 2004/047555 PCT/NZ2003/000258 8 palatability enhancing effect of the flavour-enhancing spray based on the tuna cook water. This also indicates that the positive effect on palatability of the tuna cook water is at least as strong as that for the more traditional chicken viscera based digest.

Claims (19)

1. A sprayable, flavour-enhancing agent for dry packeted pet mammal foods, said agent incorporating cook water from commercial fish processing operations that has been concentrated by evaporation.

2. The flavour-enhancing agent of claim 1, wherein the cook water emanates from tuna canning operations.

3. The flavour-enhancing agent of any preceding claim, wherein the cook water is evaporated to between about 60% and about 70% solids on a mass basis prior to incorporation in said agent.

4. The flavour-enhancing agent of claim, 3 wherein the cook water is evaporated to about 65% solids on a mass basis prior to incorporation in said spray.

The flavour-enhancing agent of any preceding claim wherein said evaporated cook water is blended with phosphoric acid and optionally a reducing sugar.

6. The flavour-enhancing agent of claim 5, further including one or more materials selected from the group comprising: water; potassium sorbate; anti- oxidising agents.

7. The flavour-enhancing agent of any preceding claim when applied to an extruded cereal-based kibble for pet mammals.

8. A method for preparing a flavour-enhancing spray for application to commercial dry packeted pet food products, said method including the steps of; I -JBWL PCT/NZ2003/000258 Received 05 August 2004 concentrating cook water from commercial fish processing operations via evaporation to a solids content of between about 60% and about 70% by mass, preferably about 65% by mass; and spraying said concentrated cook water on to the surface of said pet food products.

9. The method of claim 8, wherein the evaporation is carried out as a two- stage operation.

The method of claim 9, wherein the first evaporation stage is carried out at a temperature of about 100°C and wherein the second evaporation stage is carried out in the temperature range of between about 60°C and about

11. The method of any of claims 8 to 10, further including the step of blending the concentrated cook water with one or more materials selected from the group comprising: water; reducing sugar; potassium sorbate; anti-oxidising agents; phosphoric acid.

12. A palatable commercial dry packeted pet food product incorporating a sprayable, flavour-enhancing agent according to any one of claims 1 to 6.

13. The commercial dry packeted pet food product of claim 12, wherein said agent is incorporated in said pet food product at a mass rate of between about by mass and about 10% by mass, and preferably about 7% by mass.

14. The commercial dry packeted pet food product of claim 12 or claim 13, wherein said pet food product is an extruded cereal-based kibble.

A method of increasing the palatability of commercial dry packeted pet food products, said method including the step of spraying said pet food product with a flavour-enhancing agent according to any of claims 1 to 6. AMFNDED SHEET IP EAU k-' PCT/NZ2003/000258 Received 05 August 2004 11

16. A sprayable, flavour-enhancing agent for dry packeted pet mammal foods substantially as herein described with reference to the examples.

17. A method for preparing a sprayable, flavour-enhancing agent for dry packeted pet mammal foods substantially as herein described with reference to the examples.

18. A commercial dry packeted pet food product, said product incorporating a sprayable flavour-enhancing agent, substantially as herein described with reference to the examples.

19. A method of increasing the palatability of commercial dry packeted pet food products substantially as herein described with reference to the examples. AMENDED' SHEET IPEAfAU