**2. Cheese production**

### **2.1 World production of sheep's cheese**

Within the top 10 countries that produce sheep's cheese are mainly European countries: Greece (125,000 t) is the top producer of sheep's cheeses worldwide, followed by Spain (65,544 t) and Italy (57,595 t) at third and fifth place, respectively. There are also France (26,448 t) and Romania (24,000 t) in the eighth and ninth places, respectively (**Figure 4**). The Asian continent is the second highest producer of sheep's cheese; countries such as China (108,000 t), Syria (60,500 t), Turkey (39,600 t) and Iran (18,750 t) are positioned in the second, fourth, sixth and tenth place, respectively. In Africa, Niger is the seventh highest producer of sheep's cheese globally, with 27,927 t. The American continent has a minimal participation in the production of cheeses; the countries of interest for this chapter lack official records on the production of cheeses, so only the total production of the continent is considered (7843 t) [25].

**Figure 4.**  *World production of sheep cheeses in tons. FAO 2016 (adapted from [25]).* 

### **Figure 5.**

*Production trend in tons of sheep cheeses per continent in the years 1990, 2000 and 2014. FAO 2014 (adapted from [25]).* 

 In 1990, Asia, Africa and the Americas had lower production than the most recent data released by the FAO in 2014, evincing a tendency toward an increase in the production of sheep's cheeses on these continents. In Europe, in contrast, production has been declining since 1990 (**Figure 5**). From 1990 to 2014, it fell 12.74% and is the only continent showing this trend. Asia, on the other hand, has increased its production by 15.99%, and Africa has considerably expanded its production of sheep's cheese, doubling the amount produced in the last century, increasing production by more than 110%. America has increased its local production of sheep's cheese more modestly, from 1990 to 2014 by 21.92% [25].

### **2.2 National production**

PASO registered that during the January–May 2017 period, production in Chile was 33,300 t, with an increase of 5.4% compared to the same period of the previous year [26]. Despite this increase in national production, it continues to focus mainly on basic and mass-produced varieties, such as Gouda and Chanco, which in 2012 accounted for 90% of the total national production [27]. The remaining 10% corresponds to industrial Mozzarella cheeses (which are booming due to the growth of fast food chains that offer pizzas), melted cheeses, spreadable cheeses, Edam-type cheeses and, in smaller volumes, gourmet profile cheeses as well as craft companies engaged in the production of so-called "field cheeses" [26].

### **2.3 Sheep cheese: physicochemical characteristics**

Cheese is a product derived from milk that is obtained by the coagulation of the milk protein (casein) that is partially separated from the whey. Cheeses can be hard, semi-hard, soft ripened or unripened [28]. The differences in composition between sheep's milk and that produced by cattle and goats determine their milk coagulation properties (**Table 2**). Milk coagulation is the most important factor in cheese making, which is affected by the following properties of milk—pH, casein concentration, amount of calcium (Ca) per casein and concentration of other minerals—that define the differences in coagulation time, coagulation rate, firmness of the curd and amount of rennet used [29]. The high concentrations of protein, fat and total solids present in sheep's milk result in high yields in the production of dairy products; this species has the best cheese yield compared to goat and cow milk due to

*Production, Processing, Commercialization and Analysis of Costumer Preferences of Sheep… DOI: http://dx.doi.org/10.5772/intechopen.83806* 

its superior chemical composition [16]. Approximately 5.5 liters of milk are needed to make 1 kg of sheep's cheese, while twice as much milk is required to make 1 kg of cow's cheese [30]. Sheep's milk produces a hard curd, the result of higher levels of casein. In general, cheese products have a particular appearance and flavor: the pasta is white and the appearance of bitter flavors is difficult [31].

 The nutritional and organoleptic characteristics of the cheeses depend on the properties and nutritional qualities of the milk with which they were made, as well as the procedure in their preparation [32]. The cheese of sheep is a cheese of intense aroma, given by the volatile fatty acids present in the milk; its color is determined by the masking of the fat globules, responsible for the yellow pigmentation present in the milk of other species. For this reason, sheep cheeses are whiter and have slight grayish tones compared with cheeses made with milk from other species [30].
