**4. Goat-derived products and nutritional value**

The use of goat products was first closely related to a number of medical problems namely food allergies involving cow milk proteins. Cow milk allergy is relatively common during the first 3 years of life. Several studies report that the use of goat milk resolves 30 and 40% of the cases [12].

There are a number of unique physiological and anatomical differences between goats and cows which translate into differences in composition of goat milk and its products [40].

Goat milk products are considered dairy products with greatest marketing potential. Therefore, several characteristics of goat milk are currently the focus of increased research interest [24].

Two glasses (0.5 l) of goat milk or the equivalent amount of cheese or yoghurt can provide up to 94% of the recommended adult daily dietary allowance (RDA) of essential amino acids, 83% of calcium, and 78% of riboflavin needs, while also being a dietary source of other minerals and vitamins, albeit to a lesser extent [40].

#### **4.1. Goat cheese**

As shown in**Table 4**, goat milk is characterized by its lower concentration ofiron, zinc, and copper. López-Aliaga et al. [36] reviewed the mineral bioavailability, apparent digestibility coefficients, and the balance of calcium, phosphorus, magnesium, iron, copper, and zinc after the consumption of a goat milk diet compared with bovine milk diet in resected rats. In their work [36], they concluded that based on the particular biological, nutritional, and metabolic characteristics, goat milk can be an excellent natural food in cases of malabsorption syndrome and present a dietary alternative to bovine milk. Although goat milk has a low iron concentration, it has a higher bioavailability than in cow milk due to the presence of higher amounts

As far as contaminant metals are concerned, concentrations differ between different studies and sampling (feeding, geographic areas, pollution…), and it is therefore difficult to compare species and breeds. According to Trancoso et al. [35], in goat milk from the main Portuguese indigenous breeds, the values for the potentially toxic elements such as Cd, Pb, Co, and Ni are well below the value stipulated by the Commission of the European Communities Directive EC n° 333 [37] for Pb in milk (0.02 mg/kg). Therefore, consumption of caprine milk does not

Goat milk is an adequate source of vitamin A, thiamine, riboflavin, and niacin [11, 36, 38]. However, it presents low levels of folates, as well as vitamin B12, vitamin E, vitamin C,

**Goat milk Cow milk**

of nucleotides that in turn increase absorption in the intestine [13].

**3.5. Vitamins**

196 Goat Science

**Fat soluble vitamins**

**Water soluble vitamins**

A

and vitamin D [11, 13] (**Table 5**).

constitute a risk for human exposure to toxic elements at present in Portugal.

Retinol (mg) 0.04 0.04 Beta-carotene (mg) 0.00 0.02 D (μg) 0.06 0.08 Tocopherol (mg) 0.04 0.11

B1 Thiamin (mg) 0.05 0.04 B2 Riboflavin (mg) 0.14 0.17 B3 Niacin (PP) (mg) 0.20 0.09 B5 Pantothenic acid (mg) 0.31 0.34 B6 Piridoxin (mg) 0.05 0.04 B8 Biotin (μg) 2.00 2.00 B9 Folic acid (μg) 1.00 5.30 B12 Cobalamin (μg) 0.06 0.35 C Ascorbic acid (mg) 1.30 1.00

**Table 5.** Vitamin content of goat and cow raw whole milk (per 100g) (adapted from Raynal-Ljutovac et al. [13]).

Literature is exiguous concerning the impact of technology (cheese-making) on every nutrient of cheese, other than fat and proteins. Most studies focus on the gross composition (fat, protein, and lactose contents) of Spanish, Italian, and Greek hard or semi-hard cheeses obtained from small ruminants. Gross composition is mostly dependent on the type of cheese and can be classified according to its dry weight. Although both caprine and ovine milk have been widely used in cheese-making, production of fermented caprine milk using probiotics has not yet been developed, despite the existence of studies showing the requirements for its production. Fermentation increases the nutritional value of caprine milk and improves its flavor, making it more tolerable to the average consumer than raw goat milk.

A review by Haenlein [41] focused on several aspects of yoghurt and cheese goat composition. The benefits for human digestion included proteins with different polymorphisms, forming a softer curd on digestion and cheese-making, and the high content in short chain, medium chain, and mono and polyunsaturated fatty acids.

Regarding cheese produced from goat milk, three categories can be distinguished: traditional cheeses (produced on farms) and prepared mainly for home consumption; cheese produced on farm scale under improved conditions (frequent, for instance, in France, which produces more than 90 varieties of goat cheese) and cheese produced with a mix of sheep and goat milks (produced in all Mediterranean countries, except France) [42].

decreased. The percentages of fatty acid composition of these cheeses were 31.73% of oleic

Nutritional and Health Profile of Goat Products: Focus on Health Benefits of Goat Milk

http://dx.doi.org/10.5772/intechopen.70321

199

El-Sheikh et al. [51] studied the effect of ripening conditions in blue cheese produced from cow's and goat's milk and concluded that blue cheese (Roquefort-style) had similar

Queiroga et al. [52] evaluated the nutritional, textural, and sensory characteristics of *coalho* cheese made from goat's (CGM) or cow's milk (CCM) and their mixture (CCGM) during cold storage for 28 days. The choice of milk only seemed to have influenced the moisture, fat, and salt contents of the cheeses. CGM and CCGM showed higher amounts of short and medium-chain fatty acids (such as C6, C8, C10, and C12), and long-chain polyunsaturated fatty acids C18:2n6c. They also showed lower C16 and C16:1 contents. Their properties

**1.** Fresh and soft cheese: Gibna Beida (Sudan), Feta (Greece), and Saint Mareá and Camembert (France). Fresh type is prepared by acid curdling with a small dose of rennet. It is consumed the day after being prepared, and it contains 60–80% moisture. It has a texture similar to Queso-Blanco (Latin America). Soft cheese is produced as fresh cheese, but it is ripened for 10–30 days, and it has 55–60% moisture. For instance, Saint Moreé is surfaceripened cheese prepared by a 24 h coagulation step at 17–20°C after addition of mesophilic lactic culture (20 ml/L) and a rennet solution (6 ml/100L) and has a specific goat cheese aroma and has seven acid compounds present: hexonoic, octanoic, nonenoic, decanoic, 3-methylbutanoic, 4-methyl octanoic, and 4-ethyl octanoic acids; some were already of val-

ue in 2 days-old cheese, whereas some others only reached this value after 31.

and piercing, the cheese is ripened for 1–4 months at 9–10°C and 90–95% RH.

**2.** Blue-veined cheese: Savoy (France), Roquefort (France), and Cabrale (Spain). Curd of this cheese is prepared with lactic acid culture and rennet. It has a greenish or bluish marbled appearance after 1–2 hours of curdling and inoculated with penicillium. After salting

**3.** Semi-hard cheese: Edam (the Netherlands). It contains 40–50% moisture and is prepared by using mesophilic started and rennet. After curdling, cutting the curd, scalting, molding, pressing, and salting, the curd is waxed and ripened for 1–5 months at 8–10°C and 90–

**4.** Hard cheese: Chevrotin (France), Kefalotili (Greece), Ras (Egypt), and Manchego (Spain). It contains 30–40% moisture and is produced in warm countries or in mountainous area. Regarding Chevrotin cheese, it is prepared by culture and rennet curdling. It is preserved

Hassan et al. [44] fortified goat cheese with caramel, cocoa, and cocoa with walnuts, and these cheeses were prepared in order to be directed to children feeding, given its protein content.

acid, 24.19% of palmitic acid, and 9.32% of myristic acid.

seem to have been maintained throughout storage time.

Main goat cheese types can be classified as follows [53]:

95% RH.

for 1–3 months submerged in olive oil.

The ω-6/ω-3 ratios were at levels 6.0, 7.7, and 4.7, respectively.

properties to the ones made from cow's milk.

The production of cheese from goat milk dates back to many centuries. In recent years, the production of cheese from goat milk has acquired commercial advantage in several Western European countries because legislation is not as restrictive for this kind of milk or its products as it is for cow milk products [42, 43]. In France, for example, the production of goat cheese increased approximately 13% (in the same year) while cow cheese increased only 1%. The consumption of goat cheese has been expanding at approximately 20% per year [44].

The composition and characteristics of cheese is highly affected by the characteristics of the milk used in its production. The substitution of sheep milk by goat milk in dairy products is a frequent problem because sheep milk has a higher price. The existence of mixed flocks of goats and sheep might result in accidental or fraudulent mix-ups, affecting profitability as well as the properties and quality of the resultant cheese [45].

Calf rennet was shown to hydrolyze goat casein forming characteristic breakdown of products from individual caseins: β-I to β-V derived from β-casein as well as other primary hydrolyzed products derived αs1-casein; para-K-casein formed from K-casein and other degradation products obtained from αs2-casein. Under the same conditions, both β-casein and αs1-casein present in goat milk seemed to be more sensitive to hydrolysis than their bovine counterparts [46].

Goats milk Gouda cheese is usually made in artisanal units by traditional technology passed on from generation to generation [47] and has a special taste and flavor [42]. However, cheese made under these conditions may not have the minimum hygiene and sanitary standards necessary to obtain a product with minimum quality [48]. In the Eastern Mediterranean, an area favorable to small ruminants, most of the cheese is also produced in small artisanal units, with high temperatures and a lack of refrigeration units. The majority of productions also do not include pasteurization leading to brucellosis, listeriosis, and food poisoning due to enterotoxin production by *Staphylococci*. Therefore, in these areas "white brined cheeses" (WBC), which are ripened and stored under brine until consumption, such as Feta, Domiati, and Beyaz-Peynir, are particularly common and constitute a large share of the cheese market (>50%). Whey cheeses (such as the Myzithra, Manouri, Lor, Anari, Urda, and Skuta) are also traditional products from the Eastern Mediterranean, as the whey obtained from producing sheep's and goat's milk cheese has a very high protein content. The addition of goat or sheep milk or cream to the whey improves the yield of this type of cheese [49].

Karagozlu et al. [50] studied the Cimi Tulum cheeses (made from goats' milk) during 90 days of ripening period. These cheeses contain 57.73% total solids; 30.01% fat; 3.51% salt; 22.27% protein; 2.92% water soluble nitrogen, and 1.75% lactic acid. During the ripening process, the amounts of total solids, fat, salt, protein, water soluble nitrogen, and free fatty acids have all been shown to increase, whereas the salt and fat ratios of the total solid content have decreased. The percentages of fatty acid composition of these cheeses were 31.73% of oleic acid, 24.19% of palmitic acid, and 9.32% of myristic acid.

El-Sheikh et al. [51] studied the effect of ripening conditions in blue cheese produced from cow's and goat's milk and concluded that blue cheese (Roquefort-style) had similar properties to the ones made from cow's milk.

Queiroga et al. [52] evaluated the nutritional, textural, and sensory characteristics of *coalho* cheese made from goat's (CGM) or cow's milk (CCM) and their mixture (CCGM) during cold storage for 28 days. The choice of milk only seemed to have influenced the moisture, fat, and salt contents of the cheeses. CGM and CCGM showed higher amounts of short and medium-chain fatty acids (such as C6, C8, C10, and C12), and long-chain polyunsaturated fatty acids C18:2n6c. They also showed lower C16 and C16:1 contents. Their properties seem to have been maintained throughout storage time.

Main goat cheese types can be classified as follows [53]:

Regarding cheese produced from goat milk, three categories can be distinguished: traditional cheeses (produced on farms) and prepared mainly for home consumption; cheese produced on farm scale under improved conditions (frequent, for instance, in France, which produces more than 90 varieties of goat cheese) and cheese produced with a mix of sheep and goat

The production of cheese from goat milk dates back to many centuries. In recent years, the production of cheese from goat milk has acquired commercial advantage in several Western European countries because legislation is not as restrictive for this kind of milk or its products as it is for cow milk products [42, 43]. In France, for example, the production of goat cheese increased approximately 13% (in the same year) while cow cheese increased only 1%. The consumption of goat cheese has been expanding at approximately 20% per year [44].

The composition and characteristics of cheese is highly affected by the characteristics of the milk used in its production. The substitution of sheep milk by goat milk in dairy products is a frequent problem because sheep milk has a higher price. The existence of mixed flocks of goats and sheep might result in accidental or fraudulent mix-ups, affecting profit-

Calf rennet was shown to hydrolyze goat casein forming characteristic breakdown of products from individual caseins: β-I to β-V derived from β-casein as well as other primary hydrolyzed products derived αs1-casein; para-K-casein formed from K-casein and other degradation products obtained from αs2-casein. Under the same conditions, both β-casein and αs1-casein present in goat milk seemed to be more sensitive to hydrolysis than their

Goats milk Gouda cheese is usually made in artisanal units by traditional technology passed on from generation to generation [47] and has a special taste and flavor [42]. However, cheese made under these conditions may not have the minimum hygiene and sanitary standards necessary to obtain a product with minimum quality [48]. In the Eastern Mediterranean, an area favorable to small ruminants, most of the cheese is also produced in small artisanal units, with high temperatures and a lack of refrigeration units. The majority of productions also do not include pasteurization leading to brucellosis, listeriosis, and food poisoning due to enterotoxin production by *Staphylococci*. Therefore, in these areas "white brined cheeses" (WBC), which are ripened and stored under brine until consumption, such as Feta, Domiati, and Beyaz-Peynir, are particularly common and constitute a large share of the cheese market (>50%). Whey cheeses (such as the Myzithra, Manouri, Lor, Anari, Urda, and Skuta) are also traditional products from the Eastern Mediterranean, as the whey obtained from producing sheep's and goat's milk cheese has a very high protein content. The addition of goat or

sheep milk or cream to the whey improves the yield of this type of cheese [49].

Karagozlu et al. [50] studied the Cimi Tulum cheeses (made from goats' milk) during 90 days of ripening period. These cheeses contain 57.73% total solids; 30.01% fat; 3.51% salt; 22.27% protein; 2.92% water soluble nitrogen, and 1.75% lactic acid. During the ripening process, the amounts of total solids, fat, salt, protein, water soluble nitrogen, and free fatty acids have all been shown to increase, whereas the salt and fat ratios of the total solid content have

milks (produced in all Mediterranean countries, except France) [42].

ability as well as the properties and quality of the resultant cheese [45].

bovine counterparts [46].

198 Goat Science


Hassan et al. [44] fortified goat cheese with caramel, cocoa, and cocoa with walnuts, and these cheeses were prepared in order to be directed to children feeding, given its protein content. The ω-6/ω-3 ratios were at levels 6.0, 7.7, and 4.7, respectively.

The study made during ripening by Niro et al. [54] compared the physicochemical, microbiological, and sensorial characteristics of Caciocavallo cheeses, made from cow milk and a mixture of cow with ewe or goat milk. Different percentages of goat milk added milk to cow milk influenced compositional and nutritional characteristics of these cheeses.

**4.3. Goat butter**

acid).

**4.4. Goat meat**

100 g of meat [65].

of water that will remain in the meat.

The production of butter from goat milk is not very common, and sometimes it is artificially colored in order to look similar to cow butter [61]. There is a difficulty in cream separation, a softer texture, and it presents high tendency to hydrolytic rancidity. Idoui et al. [62] studied a traditional butter from Eastern Algeria. The results showed the presence of lactic acid bacteria (3.51 × 105 + 2.44 cfu/g), psychotrophic bacteria (1.11 × 105 + 1.31 cfu/g), moulds and yeasts (39.08 × 102 cfu/g), lipolytic bacteria (4.41 × 103+5.91 cfu/g) and the absence of total coliforms except in one sample. An analysis of fatty acids was made by GC-MS that showed a prevalence of saturated fatty acids, namely palmitic acid with a low rate of unsaturated fatty (oleic

Nutritional and Health Profile of Goat Products: Focus on Health Benefits of Goat Milk

http://dx.doi.org/10.5772/intechopen.70321

201

Goats are animals with fairly low-fat content. Several authors have indicated that the fat content of goats is 47–54% lower than that of cattle and sheep. The introduction of goat meat in diet may become an important measure for the prevention of cardiovascular diseases

Banskalieva et al. [63] also pointed out that further experimentation is needed to characterize interactions between factors such as race, age, and nutritional status in the lipid profile of goat for a better understanding of their meat quality. Little is known about the lipid profile of goat meat, but some studies indicate that oleic, palmitic, stearic, and linoleic are the predominant acids in muscles. Rhee [64] reported that goats have higher concentrations of desirable fatty

Several factors such as race, gender, stress, environment, management, diet, weight, and health condition affect the chemical composition of goat meat. Studies have shown that the average composition of meat obtained from Serbian white goats to be estimated around 75.42% water, 3.55% fat, 19.95% protein, and 1.06% minerals, whereas meat obtained from Balkan goats had a similar composition, with a water content of 74.51%, 3.92% fat, 20.55% protein, and 1.04% minerals. The energetic value was similar in both breeds and is around 580 kJ per

The quality of goat meat is influenced by its water content. The muscles contain approximately 75% water, which is distributed within the myofibrils, between themselves, between the cell membrane (sarcolemma), and between the muscle bundles. The cooling or freezing mode after slaughter, especially during the rigor, is of great importance for the percentage

Adipose tissue of slaughtered animals contains 50–95% fat, 3–35% water, 2–15% protein, and 0.1–0.6% mineral matter. The composition of adipose tissue is highly variable and depends of nutritional status, breeding, age, and type of animal. In each cell, there are 40–50 types of fats, which represent about 5% of the organic matter present in cells. The amount of fat per cell varies from tissue to tissue, for instance, cells of the nervous system are extremely rich in fats. Diet influences the deposition of fat in the muscular tissue, as well as the saturated

acids than cattle and sheep, but at levels similar to lean meat of pigs.

(SFA) and polyunsaturated fatty acid (PUFA) concentrations in cattle.

#### **4.2. Goat yoghurt**

The preparation of goat yoghurt is made using similar processes to those used in the production of cow milk yoghurt, but it has different organoleptic properties as well as nutritional composition. It presents less viscosity, has softer consistency flavor and higher acidity, during storage [55]. Goat yoghurt has free caproic, caprylic, lauric, and myristic acids. While palmitic and stearic acids were approximately equal, oleic, linolenic, and palmitic acids were lower when compared with cow yoghurt [44]. Regarding amino acid content, goat yoghurt showed about 4 mg/100g of Gly and Pro; 2 mg/100g of Lys, Thr, Ser, Glu, and Ala; and 1–2 mg/100g His, Asp and Leu. Regarding Arg, Val, Meth, and Phe, their concentrations were inferior to 1mg/100g [56].

There are significant changes in gross nutrients between fresh goat milk and yoghurt. Eissa et al. [57] found a decrease in lactose content and pH of the yoghurt after fermentation. Cold storage also resulted in significant changes in gross composition of goat yoghurt. The number of total bacteria and yeast increased significantly within 10 days of storage, decreasing thereafter. Goat milk yoghurt showed in this study lower sensory scores than cow milk yoghurt.

Bano et al. [58] concluded that mixing 75% of goat milk and 25% sheep milk in manufacture of yoghurt improved color, flavor, and texture scores of the resultant yoghurt.

Uysal-Pala et al. [59] showed that drinkable yogurts made from different goat breeds' milk and made with normal and probiotic cultures were evaluated for their sensory characteristics. Yoghurt manufacture with cows and with goats' milk (100, 75, 50 and 25%) substitution blend with cow's milk revealed that goats milk yoghurt (100%) had the highest protein content (4.2%), fat (4.3%) and caproic (c6), caprylic (c8) capric (c10), and total solids (16.2%). Generally, goat's milk yoghurt samples (100, 75, and 50%) were mostly significantly preferred to 25% goat's milk yoghurt sample at (*P* > 0.05).

Al-Abdulkarim et al. [60] studied a sample of dried fermented goat's milk product (Oggtt) obtained from the local market of Riyadh (Saudi Arabia), which was stored for 6 months at 4°C and subjected to chemical composition analysis before and after storage. After storage, total ash decreased nonsignificantly (*P* < 0.05) from 8 to 7.6%, total carbohydrates decreased nonsignificantly (*P* < 0.05) from 35.5 to 33.8%, protein increased nonsignificantly (*P* < 0.05) from 16 to 16.1 g/1, fat content was found to have the same values in all samples before and after storage at 5%, lactose increased nonsignificantly from 28.4 to 29%, acidity decreased (*P* < 0.05) significantly from 0.45 to 0.39%, and pH decreased nonsignificantly from 4.3 to 4%. On the other hand, mineral composition showed (*P* < 0.05) nonsignificant results before and after storage. Ca concentration decreased from 118 to 114 mg/kg and K concentration increased from 185.8 to 188.8 mg/kg. This is a stable product and presents good nutritional value in comparison to daily requirements for healthy human life.

#### **4.3. Goat butter**

The study made during ripening by Niro et al. [54] compared the physicochemical, microbiological, and sensorial characteristics of Caciocavallo cheeses, made from cow milk and a mixture of cow with ewe or goat milk. Different percentages of goat milk added milk to cow milk

The preparation of goat yoghurt is made using similar processes to those used in the production of cow milk yoghurt, but it has different organoleptic properties as well as nutritional composition. It presents less viscosity, has softer consistency flavor and higher acidity, during storage [55]. Goat yoghurt has free caproic, caprylic, lauric, and myristic acids. While palmitic and stearic acids were approximately equal, oleic, linolenic, and palmitic acids were lower when compared with cow yoghurt [44]. Regarding amino acid content, goat yoghurt showed about 4 mg/100g of Gly and Pro; 2 mg/100g of Lys, Thr, Ser, Glu, and Ala; and 1–2 mg/100g His, Asp and Leu. Regarding Arg, Val, Meth, and Phe, their concentrations were

There are significant changes in gross nutrients between fresh goat milk and yoghurt. Eissa et al. [57] found a decrease in lactose content and pH of the yoghurt after fermentation. Cold storage also resulted in significant changes in gross composition of goat yoghurt. The number of total bacteria and yeast increased significantly within 10 days of storage, decreasing thereafter. Goat milk yoghurt showed in this study lower sensory scores than cow milk yoghurt. Bano et al. [58] concluded that mixing 75% of goat milk and 25% sheep milk in manufacture

Uysal-Pala et al. [59] showed that drinkable yogurts made from different goat breeds' milk and made with normal and probiotic cultures were evaluated for their sensory characteristics. Yoghurt manufacture with cows and with goats' milk (100, 75, 50 and 25%) substitution blend with cow's milk revealed that goats milk yoghurt (100%) had the highest protein content (4.2%), fat (4.3%) and caproic (c6), caprylic (c8) capric (c10), and total solids (16.2%). Generally, goat's milk yoghurt samples (100, 75, and 50%) were mostly significantly preferred

Al-Abdulkarim et al. [60] studied a sample of dried fermented goat's milk product (Oggtt) obtained from the local market of Riyadh (Saudi Arabia), which was stored for 6 months at 4°C and subjected to chemical composition analysis before and after storage. After storage, total ash decreased nonsignificantly (*P* < 0.05) from 8 to 7.6%, total carbohydrates decreased nonsignificantly (*P* < 0.05) from 35.5 to 33.8%, protein increased nonsignificantly (*P* < 0.05) from 16 to 16.1 g/1, fat content was found to have the same values in all samples before and after storage at 5%, lactose increased nonsignificantly from 28.4 to 29%, acidity decreased (*P* < 0.05) significantly from 0.45 to 0.39%, and pH decreased nonsignificantly from 4.3 to 4%. On the other hand, mineral composition showed (*P* < 0.05) nonsignificant results before and after storage. Ca concentration decreased from 118 to 114 mg/kg and K concentration increased from 185.8 to 188.8 mg/kg. This is a stable product and presents good nutritional value in comparison

of yoghurt improved color, flavor, and texture scores of the resultant yoghurt.

to 25% goat's milk yoghurt sample at (*P* > 0.05).

to daily requirements for healthy human life.

influenced compositional and nutritional characteristics of these cheeses.

**4.2. Goat yoghurt**

200 Goat Science

inferior to 1mg/100g [56].

The production of butter from goat milk is not very common, and sometimes it is artificially colored in order to look similar to cow butter [61]. There is a difficulty in cream separation, a softer texture, and it presents high tendency to hydrolytic rancidity. Idoui et al. [62] studied a traditional butter from Eastern Algeria. The results showed the presence of lactic acid bacteria (3.51 × 105 + 2.44 cfu/g), psychotrophic bacteria (1.11 × 105 + 1.31 cfu/g), moulds and yeasts (39.08 × 102 cfu/g), lipolytic bacteria (4.41 × 103+5.91 cfu/g) and the absence of total coliforms except in one sample. An analysis of fatty acids was made by GC-MS that showed a prevalence of saturated fatty acids, namely palmitic acid with a low rate of unsaturated fatty (oleic acid).

#### **4.4. Goat meat**

Goats are animals with fairly low-fat content. Several authors have indicated that the fat content of goats is 47–54% lower than that of cattle and sheep. The introduction of goat meat in diet may become an important measure for the prevention of cardiovascular diseases

Banskalieva et al. [63] also pointed out that further experimentation is needed to characterize interactions between factors such as race, age, and nutritional status in the lipid profile of goat for a better understanding of their meat quality. Little is known about the lipid profile of goat meat, but some studies indicate that oleic, palmitic, stearic, and linoleic are the predominant acids in muscles. Rhee [64] reported that goats have higher concentrations of desirable fatty acids than cattle and sheep, but at levels similar to lean meat of pigs.

Several factors such as race, gender, stress, environment, management, diet, weight, and health condition affect the chemical composition of goat meat. Studies have shown that the average composition of meat obtained from Serbian white goats to be estimated around 75.42% water, 3.55% fat, 19.95% protein, and 1.06% minerals, whereas meat obtained from Balkan goats had a similar composition, with a water content of 74.51%, 3.92% fat, 20.55% protein, and 1.04% minerals. The energetic value was similar in both breeds and is around 580 kJ per 100 g of meat [65].

The quality of goat meat is influenced by its water content. The muscles contain approximately 75% water, which is distributed within the myofibrils, between themselves, between the cell membrane (sarcolemma), and between the muscle bundles. The cooling or freezing mode after slaughter, especially during the rigor, is of great importance for the percentage of water that will remain in the meat.

Adipose tissue of slaughtered animals contains 50–95% fat, 3–35% water, 2–15% protein, and 0.1–0.6% mineral matter. The composition of adipose tissue is highly variable and depends of nutritional status, breeding, age, and type of animal. In each cell, there are 40–50 types of fats, which represent about 5% of the organic matter present in cells. The amount of fat per cell varies from tissue to tissue, for instance, cells of the nervous system are extremely rich in fats. Diet influences the deposition of fat in the muscular tissue, as well as the saturated (SFA) and polyunsaturated fatty acid (PUFA) concentrations in cattle.

In ruminants, lipids from meals suffer hydrolyzation and biohydrogenation processes in the rumen, resulting in absorption of saturated fatty acids in the digestive tract. This fact could help explain the higher percentage of saturated fats in meat products obtained from ruminants. Several studies have been conducted in an attempt to determine the fatty acid profile of goat meat [66]. However, the role of certain processes such as biohydrogenation, transition of unsaturated into saturated fatty acids, elongation of fatty acid chains, metabolism, and deposition rate are yet to be fully understood.

**5.1. Overview of immune system: low-grade systemic inflammation and gut-systemic** 

Inflammation is one of the main biological processes involved in response to potentially detrimental stimuli to the body and can be classified as acute or chronic with different processes involved in each of these types. Acute inflammation is an immediate and short-lasting response to irritation, injury, or infection which leads to the activation of mechanisms such as increased blood flow, greater blood vessel permeability, and movement of white blood cells to the affected site. These mechanisms are responsible for the classic signs of inflammation: redness, edema, heat, pain, and decreased function [76]. Chronic inflammation is a long-lasting response to factors such as poor nutrition, stress, environmental toxins, and processes related to aging [76]. These prolong the inflammatory response, leading to destructive reactions which, coupled with inappropriate repair processes, eventually lead to the clinical symptoms of disease [77]. The human immune system possesses innate or nonspecific and adaptive mechanisms that work synergistically to protect the body against injury and infection. Innate immunity constitutes the first line of defence, providing immediate response albeit unspecific response to localized injury or invasion by an infectious agent. Innate immunity is triggered when the inflammasome (a large sensor protein produced by bone marrow) detects a toxic substance and stimulates the production of macrophages to destroy harmful stimuli. Macrophages are able to recognize different types of pathogens and are able to react either by producing several mediators that activate other elements further downstream inflammatory cascade (these include, for instance, toll-like receptors, cytokines, or transcription factors); or by eliminating them directly through a process known as phagocytosis. Innate immunity, however, has a limited duration and is not able to stop all pathogenic stimuli. When overtaxed, the body's

Nutritional and Health Profile of Goat Products: Focus on Health Benefits of Goat Milk

http://dx.doi.org/10.5772/intechopen.70321

203

Adaptive immunity or acquired immunity is based in highly specialized responses directed at specific antigens [77]. It can be divided into two types: humoral immunity, in which the B lymphocytes, produced in the bone marrow, generate antibodies targeting specific antigens present in the pathogen in question; and cell-mediated immunity, in which T lymphocytes, matured in the spleen and lymph nodes, recognize antigens present on infected cells and lead to their destruction. Memory cells are also a part of the adaptive immunity response and rec-

When, in the human body, the mechanisms of innate and adaptive immunity are ineffective in eliminating a harmful stimulus, illness occurs. Normal function of the cells is disrupted by processes that include leukocyte proliferation, oxidative reactions, and fibrosis caused by repeated or uncontrolled inflammatory responses. A chronic low-grade inflammatory state as a pathological feature of a wide range of chronic conditions, such as metabolic syndrome (MetS), nonalcoholic fatty liver disease (NAFLD), type 2 diabetes mellitus (T2DM), atherosclerosis, cardiovascular diseases (CVD), cancer, neurological diseases, among others, has been recognized [79–81]. The numbers of illnesses, which are related to molecular mediators

Inflammation constitutes one of the basic mechanisms of the innate immune response. In general, inflammation is a local response to cellular injury that aims not only to eliminate the toxic

**inflammatory associations**

adaptive immunity mechanisms are activated [78].

of inflammation, are large and expanding.

agents but also to promote repair of damaged tissue [78].

ognize and react to repeated exposures to specific antigens [77].

The composition of the fat in goat meat and other ruminants differs from that of monogastric animals, having larger amounts of SFA and lower quantities of PUFA, with C18:1 and C18:2 *trans* and *cis* isomers of FA are also present in goat meat. In animals, the main PUFA (C18:2n-6 and C18:3n-3) are obtained from the diet. However, in ruminants, these products suffer biohydrogenation processes in the digestive tract, originating saturated fats as well as other intermediate products, which include *cis* and *trans* C18:1 isomers and C18:2 *trans* isomers, conjugated or unconjugated [67]. While grain feeds are a food source of C18:2n-6, green grass on pastures are richer in C18:3n-3 [68], which is more desirable as it could lead to higher contents of omega-3 fatty acids in meat products.

Meat products derived from ruminants are a dietary source of CLA. C18:2 *cis*-9, *trans*-11 is the most frequent isomer of CLA, and is also present in higher amounts in the meat of ruminants fed on pasture than in the meat of ruminants fed with grain. Despite the fact that a fraction of this fatty acid occurs in the rumen, about 70–80% of the acid present in the tissues results from endogenous transformation C18:1 *trans*-11 by the enzyme Δ9 desaturase [69]. Therefore, the difference in CLA concentration in the tissues results mainly from the amount of C18:1 *trans*-11 absorbed in the rumen.
