GB2105167A - A method for the production of cheese - Google Patents

Abstract

In a method for the production of cheese on the basis of milk which is concentrated by ultrafiltration optionally combined with diafiltration, texture and coherence of the cheese are obtained by making the surface of the cut and separated pieces of curd sticky be means of moistening with a solvent or adhesive before the pieces of curd are shaped into cheeses.

Description

SPECIFICATION A Method for the production of cheese In the traditional method for the production of cheese the milk is caused to curdle by the addition of rennet combined with a starter. The coagulum is then cut into cubes and the curd gives off some whey and forms cheese grains. The liberation of whey can be facilitated by stirring the mixture of whey and cheese grains, optionally while heating. Cheese grains and whey are then separated and the cheese grains are transferred to moulds. The whey is a waste produce wsacs as rsej for instance as fodder.

When cheese is formed in this manner froc cseese graaos which are first separated and subsequently compressed into an aggregate mass the cheese obtains a characteristic "structure" or "texture" which depends on the curdling techniques used for the individual types of cheese. It is to be understood that the so-called structure or texture appears when the cheese is cut through or cut into slices seeing that in the cut there will still be traces of the boundary surfaces of the cheese grains, and there will be a certain porosity.

It is well known that the yield of cheese production can be increased by 16-18% when the milk is concentrated by ultrafiltration and the retentate is used for the production of cheese (French patent No.

2,052,121).

In a known method for the production of cheese on the basis of the retentate from ultrafiltration of milk, the retentate is inoculated with a bacteria culture and rennet is added whereafter the retentate is curdled to individual cheeses each in its own mould. It has been possible in this way to produce feta cheese.

By this method one has succeeded in producing cheese which from a taste point of view was hardly distinguishable from cheese produced by the traditional method, but the cheese lacked structure ortexture because when cutting through or slicing the cheese the cut appeared as a homogeneous surface without porosity or pattern and for that reason the cheese was not always accepted by the consumers.

Attemps have been madeto produce cheese on the basis of retentate which cheese not only with regard to taste but also in texture was like traditionally pro duced cheese, viz. by dividing the curdled retentate into cubes, separating them and compressing them in moulds. However, itturned outto be impossibleto make the thus prepared cheese grains stick together, and the cheeses produced were inclined to break with fractured surfaces where sticking together had not taken place.

It is the object of the invention to provide a method to impart structure or texture to cheese when the cheese is produced on the basis of milk concentrated by ultrafiltration, curdled, cut up and collected, in such manner that coherent and stable cheeses are obtained which are identical to traditionally produced cheese not only with regard to taste but also with regard to appearance.

In the method according to the invention milk is concentrated by ultrafiltration, optionally combined with diafiltration, the retentate inoculated with lactic acid bacteria and curdled by the addition of rennet and/or acid, the curd cut up into small pieces which are separated and then shaped into cheeses, and the novel feature ofthe invention isthatthe surface ofthe cut and separated pieces of curd are made sticky by moistening with a solvent or adhesive before they are shaped into cheeses.

In accordance with the invention the moistening of the cheese grains can take place by spraying of a solvent or adhesive, or the cheese grains can be immersed in a bath of solvent or adhesive.

As the solvent or adhesive according to the invention can be used milk or a milk product like e.g. milk retentate or a caseinate solution. It is also within the invention to use other solvents or adhesives such as warm water, permeate from diafiltration or solutions thereof containing salt. The main thing is to use agents which can make the cheese grains stick together and that the solvent or adhesive is acceptable from a health point of view.

If the moistening takes place by immersion in a bath, the bath can suitably consist of water, permeate or salt solutions thereof having a temperature of 30-40"C. The mutual separation of the cheese grains can conveniently take place during the immersion in the bath by performing a lenient stirring of the mixture of liquid and cheese grains, optionally intermittently. The cheese grains are kept immersed in the bath for a period up to 30 minutes depending on the temperature of the cheese grains prior to immersion.

The cutting of the coagulum to form the cheese grains can take place in a well known manner by pulling cutter frames with wires or knives through the coagulum in such a way that it is divided into cubes.

The cutting can also be performed by pressing blocks of coagulum through a system of cutting wires or knives so that the coagulum is divided into strands of square cross section, and these strands are then cut into cubes or prisms. These cubical or prismatic cheese grains preferably have a side length of 5 to 15 mm depending on whether a fine or a coarse texture of the cheese is desired.

After cutting the cheese grains are separated and spread if the moistening is to take place by spraying.

No special measure is required to separatethe cheese grains seeing that the cut pieces of curd readily separate of themselves, e.g. when trasported on a conveyor.

The moistening by spraying can be carried out in different ways and so can the immersion in a bath and removal ofthe cheese grains from the bath. The techniques used for these purposes are irrelevant to the invention and do not require any detailed description.

When the cheese grains produced by the method according to the invention have been made sticky on the surface they can be transferred to individual mouldsto form the final cheeses orthey can be trans- ferred to relatively large moulds and after compression be divided into several smaller cheeses. Finally, the cheese grains can be transferred to relatively tall moulds in which they consolidate under gravity.

After the transfer of the cheese grains to moulds the cheeses are treated further essentially in the traditional manner including pressing and/orturning and salting.

When shaping has taken place at above 30"C the cheeses are slowly cooled to about 22"C so that an after-souring can take place. The cooling is preferably started 4-6 hours afterthe addition of bacteria culture and the cheeses are after-soured till the next day.

Salting is performed when it is suitable forthe cheese type in question.

The method according to the invention is explained in more detail with reference to the drawing which illustrates by way of a block diagram an example of producing feta cheese.

The starting material is 1000 kilos of full milk containing 3.4% protein,3.4% fat and 12.2% total solids.

Pasteurization and optional standardization is effected at 72"C for 15 seconds. The milk is then subjected to ultrafiltration which yields 708.5 kilos of permeate with 4.9% solids and 291.5 kilos of rententate with 30.05% solids. The ultrafiltration is performed with an average pressure of 4.0 bars using a DDS membrane type GR 61 P. The rententate is then pasteurized at 90"C for 1 minute and homogenized at 60"C with a pressure of 50 bars. At the inoculation step which takes place at 30 C 1-2% starter of the cheddar type is added and optionally youghurt culture. The initial souring then proceeds for 60 minutes at 30"C, and in the subsequent mixing stage there may optionally be an addition of bleaching agent ( < lml/kilo) and lipase composition ( < 0.15/kilo).For the curdling is used 0.7 mil/kilo of rennet, e.g. Chr.

Hansen's standard rennet. The curdling lasts 15 minutes whereafter the coagulum is cut into cubes.

Next, the cubes are immersed in a bath of permeate at 30 C for 30 minutes with intermittent stirring whereby their surfaces become sticky so that after transfer to moulds the curd will be shaped into a coherent mass of good texture. The shaped cheeses are then turned 5 times at intervals of 10-30 minutes at 30"C whereby some whey drains off. Thereafter the moulds are removed and the cheeses are placed in cans and 25 kilos of permeate are added.The cheeses are aftersoured at about 22"C for 20 hours whereby some more whey is given of resulting in 187.4 kilos of fresh unsalted feta cheese with 42% solids. 8.2 kilos of salt are then added to the fresh cheese which is cooled to 4"C for 14 days, and the final product is 200.2 kilos of salted feta cheese having 43% solids, 3.5% salt and about 40% fat in the solids.

The method according to the invention is especially suited forthe production of so-called "fished" cheese such as Tilsit, Feta, Blue Cheese and Camembert which are varieties of cheese that can be made from milk concentrated by ultrafiltration. However, the invention is not restricted to the production of these varieties of cheese since it is undoubtedly possible to produce othertypes of cheese on the basis of rentate using the technique according to the invention.

In the foregoing example of production of feta cheese the method has been described using full milk for concentration by ultrafiltration but it is equally possible to carry out the method according to the invention by ultrafiltration of skimmed milk and subsequent addition of fat (cream, milk fat or vegetable fat) to the retentate.

Claims (8)

1. A method for the production of cheese on the basis of milk which is concentrated by ultrafiltration, optionally combined with diafiltration, in which the retentate is inoculated with a starter and curdled by the addition of rennettand/oracid, the curd is cut into small pieces which are separated and then shaped into cheeses, characterised in that the surface of the cut and separated pieces of curd are made sticky by moistening with a solvent or adhesive before they are shaped into cheeses.

2. A method as claimed in claim 1, characterised in that the moistening takes place by spraying a solvent or adhesive.

3. A method as claimed in claim 1, characterised in that the moistening takes place by immersion in a bath of solvent or adhesive.

4. A method as claimed in claims 1 and 3, characterised in that the separation of the cheese grains is effected during immersion in a bath.

5. A method as claimed in claims 1, 2, and 3, characterised by the use as solvent or adhesive of milk or a milk product such as milk retentate or caseinate solution.

6. A method as claimed in claims 1, 2, and 3, characterised by the use as solvent or adhesive of water, permeate from ultrafiltration or salt containing solutions thereof.

7. A method as claimed in claim 1, characterised in that the cheese grains are at a temperature of 30-40"C when they are shaped into cheeses.

8. A process substantially as described above and disclosed in the specification.