Liquid food product on dairy basis for cats and a process for the preparation of these products.

The invention relates to a Liquid food product on dairy basis for cats and to concentrated Liquid products intended for dilution to such a Liquid food product, as well as processes for preparing these products.

It is common knowledge that cats like milk, but that this may give digestion problems due to the relatively high lactose content of cow's milk (approximately 4.6% by weight). These problems can be eliminated by diluting the milk with water prior to consumption, however, this has the disadvantage that also the positive food components, i.a. proteins, are being diluted and consequently that the cat will absorb these components to an inadequate extent.

A milk product for cats based on the dilution principle is known from Swiss patent specification 632 903. With the maximum indicated water-addition of 30% the Lactose content would be fairly acceptable; the protein content and the other food components content would, however, be too low. In a smaller dilution, however, the disadvantage of a too high Lactose content would remain.

A new Liquid food product for cats missing these drawbacks has been found, which product has in addition the advantage that by using it the animals' health and exterior are beneficiaLLy affected.

This new, Liquid food product according to the invention is characterized by the fact that this product comprises 1.5 - 3.5% by weight of Lactose and 3.5-5.0% by weight of protein, based on the total product, and fat. PreferabLy the Lactose content of this product ranges between 2.0 and 3.0% by weight.

The food product according to the invention comprises an amount of protein that is-at Least equal to that of cow's milk (approximately 3.5% by weight); a protein content higher than 5% by weight, however, is meaningLess. The protein may consist of milk protein originating from skimmed milk, or partiaLLy skimmed milk or skimmed or partially skimmed milk powder, combined or not combined with whey-protein (e.g. originating from delactosed, either or not desalted whey or a whey-protein concentrate obtained by ultrafiltration) and/or calcium- or sodium caseinate; preferably the protein consists of casein, caseinate and/or whey-protein.

For the cat's health care, and particularly to prevent skin diseases and to promote the gloss of the fur, it is recommended that the fat contains a high content of polyunsaturated fatty acids, preferably at Least 40% by weight. SuitabLe fats are for example corn oil, sun flower oil, soy bean oil, etc. The most benificial results are obtained in case the total fat content of the product ranges from 1-3% by weight.

It is common knowledge that cats are frequently troubled by skin diseases and that so-called complete dry foods cannot prevent these skin diseases to a sufficient extent, as the incorporation of fats having a high content of polyunsaturated fatty acids in these dry foods is not possible in connection with preservation problems (oxidative rancidity). The food product according to the invention is therefore not only a treat for the cat, but also contributes to the animal's health.

Furthermore it is recommended to incorporate in the food products according to the invention vitamins, minerals, flavours and fiLLers. The vitamins and minerals to be applied and the proportions thereof have to correspond with the cats' needs as known from Literature. The preferably applied fillers serve as calory source. PreferabLy a carbohydrate highly digestible for the cat is chosen therefore, such as hydrolyzed or not hydrolyzed or modified or not modified starch.

An appropriate hydrolyzed starch is for example dextrine maltose. An appropriate quantity of filler ranges between 2 and 6% by weight, preferably between 3 and 5% by weight.

PreferabLy a small amount of yeast extract is included in the food product. This does not only provide a flavour to the product that is pleasant for the cat, but moreover, it provides a real contribution to the vitamin content, particularly B-vitamins.

In addition synthetic flavours may be included such as meat- or fish-flavour.

The invention also covers Liquid products which are fermented by means of Lactic acid bacteria, e.g. strains of the types Lactobacillus bulgaricus, Streptococcus thermophilus or Streptococcus acidophilus or mixtures thereof up to a pH Lower than 5.

The invention also encompasses concentrated Liquid products providing one of the above described Liquid food products on dairy basis for cats after dilution with water.

The Liquid food products according to the invention can be brought on the market in a sterilized or pasteurized form. Therefore the products are either brought into the final container after pasteurisation, or brought into the final container after aseptical sterilisation, or after bringing into the final container the products are sterilized or pasteurized in said container.

The final container may be for example tins, bottles and cartons.

The Liquid food products according to the invention may be prepared in the following three ways:

Process 1

Skimmed milk or partially skimmed milk or a mixture thereof with delactosed, desalted or not desalted whey is diluted with water to the desired Lactose content. SubsequentLy by means of caseinate the protein percentage is brought at the required content. Thereafter the fat phase, vitamins, minerals, fillers and flavours can be added to the mixture. The total mixture is homogenized with a high-pressure homogeniser at a temperature of e.g. ₆₀^o_C.

After cooling the food product is filled up into a tin package, thereafter the filled and sealed tin is sterilized or pasteurized. Also the food product may be filled up into bottles, said filled-up bottles being sterilized or pasteurized.

After homogenisation and cooling the food product may also be UHT-sterilized by means of a flow steriliser under the time-temperature conditions known for dairy products. Thereafter or after buffering in a sterile tank it is filled up aseptically into carton packages.

If a Limited storage life is sufficient, pasteurisation of the food product prior to filling-up into the final package will suffice. For this the above mentioned packages can be used again.

Process 2

The required proportions of milk powder and/or delactosed, desalted or not desalted whey powder or whey-protein-concentrate obtained by ultrafiltration are added to water and subsequently dissolved therein, in order to adjust the required Lactose content.

Thereafter caseinate is added to this mixture, in order to obtain the predetermined protein content.

SubsequentLy the other ingredients, such as mentioned under Process 1, are added, thereafter the mixture is homogenized and cooled as described in Process 1.

The food product obtained according to this process can be packaged and preserved in the same ways as described in Process 1.

In the two processes the quantity of water can be chosen in such a manner that the obtained food product is either directly ready for consumption or must be diluted with a quantity of water before consumption.

Process_3

The Liquid product obtained according to Process 1 or 2 is homogenized in the manner as described in Process 1 and cooled to 30°-45°C, dependent on the available process time. The dairy product obtained in this manner is fermented with Lactic acid bacteria, e.g. Lactobacillus bulgaricus, Streptococcus thermophilus or Streptococcus acidophilus, up to a pH of 3.5-5.0 and preferably up to a pH of 4.2. After fermentation the obtained dairy product is stirred and filled-up in the manners as described in Process 1.

The food products and the said processes are elucidated in details in the following examples.

Example 1

A mixture is prepared of 6.2% by weight of concentrated skimmed milk (32% dm) and 2.9% by weight of concentrated partiaLLy delactosed whey (dm 32%) and this mixture is diluted with water up to 85% by weight.

Subsequently to this mixture 2.8% by weight of calcium caseinate, 2.0% by weight of corn oil, 5.0% by weight of maltodextrine (e.g. type Paselli SPG 20 of Avebe), 0.3% by weight of yeast extract (e.g. type Gistex of Gist-Brocades), 0.014% by weight of a mixture of vitamins and minerals (containing the vitamins A, B₁, B₂, ^B_6' C , D₃, E, niacine, choline and calcium panthotenate among others) and a flavour (e.g. type tuna fish 2 m 43403 of Naarden InternationaL) are added.

The whole mixture is completed with water up to 100% by weight, homogenized with a pressure of 2 x 300 bars at 50°C and cooled.

The obtained product is sterilized in a flow steriliser at 140°C for 5 seconds'and aseptically filled up into carton packages.

Example 2

A solution is made of 3.2% by weight of skimmed milk powder and 3.2% by weight of partially delactosed whey powder in 70% by weight of water. To the resulting solution 2.3% by weight of sodium caseinate, 2.0% by weight of corn oiL, 4.0% by weight of maltodextrine, 0.3% by weight of yeast extract, 0.014% by weight of a mixture of vitamins and minerals and a flavour (e.g. type beef 2 m 36174 of Naarden International) are added.

The whole mixture is completed with water up to 100% by weight, homogenized with a pressure of 2 x 250 bars at 60°C and after cooling the product is filled up into glass bottles which are subsequently sterilized in a continuous bottle-steriliser at 115°C for 15 minutes.

Example 3

The composition and preparation are as described in ExampLe 2, with the proviso that 5.0% by weight of whey protein concentrated powder (60% by weight of protein/ dry material) obtained by uLtrafiLtration, is applied instead of the milk powder and the deLactosed whey powder and that 2.2% by weight of sodium caseinate, 2.0% by weight of maltodextrine and 0.6% by weight of yeast extract is applied and that after pasteurisation in a flow pasteurizer (75⁰C for 10 seconds) the product is filled up into carton packages.

Example 4

Water is used for diluting 33% by weight of skimmed milk up to 70% by weight.

SubsequentLy 2.8% by weight of partiaLLy delactosed whey powder, 2.5% by weight of sodium caseinate, 2.0% by weight of corn oiL, 3.0% by weight of starch (e.g. Snowflake 12616 and 06309), 0.3% by weight of yeast extract, 0.014% by weight of a mixture of vitamins and minerals, and a flavour, are added thereto.

The obtained mixture is completed with water up to 100% by weight, homogenized with a pressure of 2 x 250 bars at 60°C, cooled and filled up into tins. The fiLLed tins are sterilized in a continuous tin-steriliser at 125°C for 10 minutes.

This product has a more viscous character than the products of examples 1 up to and including 3.

Example 5

A product is prepared according to example 4. After homogenisation the obtained product is inoculated with 0.025% by weight of a bacteria culture of Lactobacillus bulgaricus and Streptococcus thermophilus (1 : 1 ) at 42°C. After fermentation to pH 4.2 at 42⁰C, the product is cooled and then filled up and preserved as described in example 4.

On account of the fermentation the Lactose content in the final product is about 30% lower than in example 4.

Example 6

A solution is made of 4.1% by weight of skimmed milk powder and 4.1% by weight of whole milk powder (28% by weight of milk fat) in 70% by weight of water.

Thereafter 5.0% by weight of sodium caseinate, 3.0% by weight of sunflower oil, 5.2% by weight of maltodextrine 0.6% by weight of yeast extract, 0.028% by weight of a mixture of minerals and vitamins (vide example 1) and a flavour are added to this solution (vide example 2).

The whole mixture is completed with water up to 100% by weight.

The said product is further processed according to Process 2, with the proviso that the mixture is homogenized with a pressure of 2 x 250 bars at 50°C, after cooling the product is filled up into tins and sterilisation takes place as described in example 4. Prior to use, this product should be diluted by mixing 1 part of food product with 1 part of water.

The examples are summarized in the following table: <tables id="tabl0001" num="0001"><img file="EP0241097A1_D0001.tif" /></tables>