CHEESE TECHNOLOGY

Module 8. Manufacture of different varieties of cheese

Lesson 17
CHEDDAR CHEESE

17.1 History

Cheddar cheese originated from the village of Cheddar in Somerset, South West England. Cheddar Gorge on the edge of the village contains a number of caves, which provided the ideal humidity and constant temperature for maturing the cheese.

Central to the modernization and standardization of Cheddar cheese was the nineteenth century Somerset dairyman Joseph Harding. Owing to the technical developments, promotion of dairy hygiene and unremunerated propagation of modern cheese-making techniques he suggested, he has been described as the father of Cheddar cheese. Harding introduced new equipment into the process of cheese making, including his ‘revolving breaker’ for curd cutting, saving much manual effort. The ‘Joseph Harding method’ was the first modern system for Cheddar production based on scientific principles. He and his wife were behind the introduction of the cheese into Scotland and North America. Joseph Harding's son, Henry Harding, was responsible for introducing Cheddar cheese production to Australia.

Cheddar is the most popular cheese in the United Kingdom, accounting for 51% of the country's £1.9 billion annual cheese market. In 2010, the UK produced 2,58,000 tons of Cheddar cheese. It is the second most popular cheese in the USA (behind Mozzarella), with an average annual consumption of 4.5 kg per capita.

17.2 Chemical Composition

Table 17.1 Composition of Cheddar cheese made from cow and buffalo milk

17.3 Method of Manufacture

The manufacturing of Cheddar cheese consist of (a) addition of starter culture to milk; (b) coagulating milk; (c) cutting the resultant coagulum into small cubes; (d) heating and stirring the cubes with the concomitant production of a required amount of acid; (e) whey removal; (f) fusing the cubes of curd into slabs by cheddaring; (g) milling the cheddared curd;(h) salting ; (i) pressing ; (j) packaging and ripening. The detailed method is shown in Fig. 17.1.

17.3.1 Cheddaring

Steps upto cutting, cooking and whey removal are similar to the other varieties of cheese but the step which separates Cheddar cheese from other varieties is cheddaring. It is a step which involves a series of operations consisting of packing, turning, piling and re-piling the slabs of matted curd. This process of piling and re-piling is repeated every 15 min. This process squashes the individual curd particles as well as releases more whey. In this process, the curd granules fuse under gravity into solid blocks. Rapid matting of the curd particles occurs under the combined effect of heat and acid. The original rubber-like texture gradually changes into a close-knit texture (‘chicken breast’ structure, typical of Cheddar cheese) with the matted curd particles becoming fibrous. When the acidity of whey reaches 0.45-0.50% and cheddaring is complete, the curd is milled. The milled curd is salted, pressed, packaged and kept for ripening in the manner followed for all cheese varieties.

Later research has suggested that cheddaring is not an essential step and serves no purpose other than to provide a holding period which is required for acidity development and whey removal. The major factors affecting the process of whey removal are acidity and temperature of the curd. Mechanical forces (pressure and flow) are important in the development of fibrous structure in the curd. Fibrous structure cannot be brought about by pressure and deformation unless the curd has reached a pH of 5.8 or less. This suggests that pressure and flow serve to knit, join, stretch and orient the network of casein fibres already formed in response to rising acidity. This structure formation is also influenced by temperature and moisture.

17.4 Texture of Cheddar Cheese

Cheddar cheese has a texture that is intermediate between those of high pH cheese (Gouda cheese), which flows readily when a force is applied and the low pH cheeses (Cheshire) which tend to deform, by shattering, only at their yield point. Much of the protein in Cheddar cheese is in the form of smaller particles than Gouda. As the pH decreases towards that of the isoelectric point of paracasein, the protein assumes an increasingly more compact conformation and the cheese becomes shorter in texture and fractures at a small deformation.

17.5 Flavor of Cheddar Cheese

Flavor of Cheddar cheese is affected by a number of factors like milk fat, proteolysis, starter and non-starter bacteria etc. It has been studied that when a series of batches of Cheddar cheese were made with fat content increasing from 0 to 4.5%, the flavor improved as the fat content increased but above a certain limit, there was no increase in flavor. This suggested that the water-fat interface is important and the flavor components are dissolved and retained in the fat. Thus, it is clear that fat plays an important role in flavor development of Cheddar cheese. As breakdown of casein is also involved in the production of Cheddar cheese flavor, proteolysis plays a major role in flavor development. Other than milk fat and proteolysis, the factors that affect flavor of Cheddar cheese are starter and non-starter bacteria.

Fig. 17.1 Flow diagram for cheddar cheese