Sheep milk Cheese
In Uruguay, sheep production is traditionally oriented to wool, meat being a by-product of the system. In 1987, due to the low international price of wool, the first attempts of sheep milking were started, mainly the Corriedale breed. The milk produced in those years has been mainly destined to the production of ripened (Manchego, Sardo, Pecorino type) and fresh cheese (Feta type).
In 1991, some practical experiences started to be implemented not only in obtaining products derived from sheep milk but also some goat milk with producers interested in a plant in the Rural Development Society of Durazno, and their intention was to continue with this line of work. In Uruguay, these kind of products had been a growing interest and there were two companies producing sheep’s milk cheeses for the foreign markets. One company had already been authorized to export sheep cheeses to Brazil. In 1992, with funding from INI A a sheep dairy was set up in the Experimental Field N° 1 (Migues, Canelones Department) of the Faculty of Veterinary, UdelaR. In the dairy, they performed activities intended to evaluate management, health, feeding, breeding and genetic alternatives to familiarise Uruguay in this non-traditional production system. First, it was by the milking of the Corriedale breed and, since 1993, it began the insemination with the dairy breed Milchschaf (Kremer 1995). Corriedale breed was developed in New Zealand, and was obtained by crossing Merinos with long-wool rams. It is well known for being a widespread breed, it is estimated that it ranks second in global stocks, after the Merinos, it is a dual-purpose animal (meat and wool), with a good body and robust development, and a milk production of 0.7 liters per day (Kremer 2005). From the milk of the flock of sheep, the Sardo cheese type which is a hard, fatty, prepared with whole milk, acidified by lactic bacteria culture and coagulated by rennet and/ or specific enzymes was developed. It has a minimum aging of 90 days, is cooked, molded, pressed, salted and matured curd cheese; it is hard, consistent, crisp and grainy. It has a characteristic spicy flavor, pleasant, clean, well-developed flavour and white yellowish colour (Fig. 4.3).
FIGURE 4.3 Proposed protocol for manufacturing the type Sardo sheep cheese.
Other cheeses produced and currently available in the Uruguayan market are acidic fresh cheeses (Feta and Ricotta) and ripened cheeses (Pecorino as an example).
Sheep milk has a number of advantages compared to cow milk, it has a greater cheese making ability, which is evidenced in its higher yield (1 kg of cheese per 5 liters of sheep milk, whereas 10 liters of bovine milk are needed for equal yield);
regarding technological parameters, sheep milk responds differently by coagulating faster, due to its higher protein content.
The two main components that affect cheese yield are casein and fat. Casein is the key component in the process of curd formation which traps fat globules; in the casein we pay attention to the relationship with the other components of the milk to predict the potential quality and cheese yield. The casein/fat (C/F) ratio is critical in controlling the final fat in dry matter (FDM) of the finished cheese. The specifications of FDM are defined for many cheeses with identity standards that already exist in several countries (Wendorff 2003).
Currently, the Uruguayan consumer has no habit of consumption of cheeses made from sheep’s milk, because the taste is “stronger” than cheeses made with cow’s milk. Moreover, domestic production of sheep cheeses does not reach volumes that allow exporting the product, so the production is oriented on a small segment of the population, preventing the sheep dairy from developing as a profitable activity. From the total volume, sheep cheeses represent about 0.4% of cheese production. It has been evidenced that increasing of production of this type of cheese is related to the demand behavior of the current consumer which presents an increment in demand. Among them are also included niche products, also known as “delicatessen”, whose market position is based on its sales margin and not in its sales volume. These products are derivatives made from sheep’s milk, among which there are a variety of highly valued, accepted and growing demand products (Kremer 2005). The sheep’s milk is an alternative category in Uruguay and the development of cheese of this species has been an interesting possibility in the domestic and other markets. Certainly the types for elaboration should be standardized to keep this cheese on the inside of the market.
On the other hand, Bermudez and Reginensi (2014) indicate that sheep’s milk is a productive alternative for small farms in Uruguay, because they normally require less investment for implementation. They also make reference to cheese making in particular; there are two main approaches, on one side imitation of products from other countries, mainly European and on the other, the development of authentic products (genuine) based on the re-engineering of specific biological aspects associated with the “territoriality”. This includes the specific regional product (Paxon, 2010, cited by Bermhdez and Reginensi, 2014). These authors have developed a culture for use in the manufacture of cheese with sheep milk, characterizing lactic acid native bacteria (Reginensi et al. 2013).