The production of an 80 kilos wheel of Emmental cheese requires 1,000 litres of milk, representing the daily yield of approximately 80 dairy cows.
The milk is constantly stirred in a large cheese vat and heated to a temperature of 32 *C, which represent the melting point of milk fat. Rennet and bacterial flora are then added. Rennet is obtained from the stomach wall of calves and causes the milk to coagulate and to form a mass of curd within 30 minutes. The bacterial flora affects the fermentation and maturing processes of the cheese.
As soon as the curd has reached the desired consistency, depending on the type of cheese, it is cut by means of the cheese-harp into granules the size of wheat grains, the so-called "cheese grains". The watery by-product known as the "whey" separates from the cheese mass (the curd).
Cheese heating and Separation
The mixture of whey and cheese grains is then heated to about 53 *C whilst being continuously stirred by the stirring mechanism until the cheese grains have obtained the desired consistency.
(The more you cut or granule the curd and the more you heat up the milk, the harder will become the cheese, because more liquid or "whey" will be released from the curd).
Approximately 2-1/2 hours after adding the rennet the mass is lifted out of the cheese vat by slipping a large piece of cheese cloth under the clotted mass and pulling the corners together to make a sack. The dripping curds are then hauled by a pulled block. Industrially, this is done by machines through a pipe.
On the pressing table, the curd is placed in a circular wooden form and pressed. The moisture, or whey, is squeezed out and the cheese is then formed into its round shape. In the course of the day the cheese is turned several times, repacked in a fresh cheese cloth on each occasion and pressed again.
Brine Bath and Salt Cellar
The cheese is placed in the salt cellar to cool for one day. There the wooden form is removed and the cheese is put to float in vat brine for 1 or 2 days, where it gives off water and absorbs salt, gradually developing a rind. Thereafter, the cheese is stored in the salt cellar for about 10 days, where it is salted, washed and turned twice a day.
The next stage is the storage in the warm fermentation cellar at 20 to 23 *C and a relative humidity of 75 to 78 % during a period of 6 to 8 weeks. During the fermentation carbon dioxide gas develops, which account the holes in the cheese.
(The warmer the fermentation cellar is, the more carbon dioxide gas develops and the bigger will be the holes).
After four months, experts will grade of cheese as 1st, 2nd or 3rd choice, according to the quality of the product. Then the maturation will continue, since taste and flavour will continue to develop.
The length and the type of maturation play an important part. The maturing process of harder cheeses progresses slowly from the centre towards the rind, while mold cheeses mature from the rind to the centre of the cheese. In certain cheeses, herbs or even ashes will be added to increase the flavour.