**2.2 Effect of starter cultures on camel milk cheese composition**

It has been stated that a higher cheese yield (13.44 %) was obtained for cheese made using R-707 culture [12]. Khan et al. [11], who reported a 13.2% yield from fresh SWC made from camel milk using a starter culture, discovered the same outcome. SWC manufactured using the CHN-22 culture, on the other hand, was


#### **Table 1.**

*Composition of commercial starter cultures; Blended = mixture of mesophilic and thermophilic cultures.*


*a–dMeans with different superscripts within the same row are significantly (P < 0.05) different.1 pH values in the table are mean ± SD of n = 2. STI-12 and RST-743 were inoculated at 37°C, whereas R-707, XPL-2, and CHN-22 cultures were inoculated at 30°C for manufacturing of soft white cheese from camel milk. \**

*P < 0.05. \*\*P < 0.01.*

*\*\*\*P < 0.001 [12].*

#### **Table 2.**

*Acidification rate of camel milk using different commercial starter cultures.*

noted to have poor cheese production and greater moisture content. It is possible that this is a result of the extremely fragile cheese curd produced by this slowly acidifying culture, which causes a larger loss of tiny curd particles through the pores of the cheesecloth during whey drainage. The study found that by employing starter cultures, fresh soft white cheese could be produced. The most palatable cheese was discovered to be fresh, soft, and white, made from camel milk and starter culture. Without starting cultures, camel milk cheese had a very high pH and high moisture content, which could encourage the growth of harmful bacteria and result in major health issues [11].

When compared to other cultures, cheese prepared with RST-743 was shown to contain more fat. The strength of gels' rheological and microstructural features, as well as the increased curd loss from the cheese vat, may all be contributing factors to these variances in cheese fat [13]. Additionally, it was discovered that the starter culture employed to make the cheese had a substantial impact on the protein, ash, and total solids contents of SWC [12]. The original milk composition and cheese-making processing conditions may be to blame for the fluctuation of TS seen in the cheese. Depending on how the cheese is processed and how the whey is drained, the majority of the TS constituents, such as protein and fat, are gradually concentrated into the cheese curd. Additionally, throughout the cheese-making process, the type, ash level, and salt addition can all have an impact on the minerals present in the cheese. The acidification process is crucial for the elimination of colloidal minerals from casein micelles, coagulant retention in the curd, syneresis of the gel, coagulum strength, and cheese yield, in addition to its effect on milk clotting.

#### **2.3 Effect of starter culture on cheese texture**

It was reported that compared to cheese made with the STI-12, R-707, XPL-2, or CHN-22 cultures, camel milk SWC made with the RST-743 culture had a stronger

#### *Innovative Approach of Cheese Making from Camel Milk: A Review DOI: http://dx.doi.org/10.5772/intechopen.108700*

resistance to deformation. However, compared to SWC prepared from camel milk using the STI-12, RST-743, and R-707 cultures, camel milk SWC made using the XPL-2 and CHN-22 cultures showed lower deformation values. The enhanced resistance to deformation compared to camel milk soft cheese made with cultures R-707, XPL-2, and CHN-22 may be due to the lower moisture and higher TS levels of camel milk SWC manufactured with cultures STI-12 and RST-743 [12].

This study has notified that the moisture content and protein content of camel milk SWC produced with the XPL-2 culture were comparable to those of cheese produced with the RST-743 and STI-12 cultures. The SWC produced with XPL-2 suffered considerable syneresis during storage, in contrast to other cheeses, which may account for its low resistance to deformation [12]. The features of a cheese's texture have been demonstrated to be influenced by its moisture content in the past [14, 15]. Cheese samples with lower moisture concentrations exhibit resistance to deformation. Acidification, which affects the cheese's pH, and casein matrix hydration, which results in an increase in the curd's stiffness with a pH decrease, both have an impact on the cheese-making process's curd formation (**Figure 1**).

The study on SWC prepared from camel milk using several cultures found that the cheese's textural attributes varied, see Ref. [12]. The report showed that compared to camel milk SWC prepared using other cultures, RST-743 SWC had significantly higher firmness and brittleness characteristics. A decrease in pH caused by the acidification of cheese milk during cheese production has an impact on the moisture content and, as a result, the mineral content of the cheese curd [16]. This has been explained by the degree of casein sub-micelle swelling brought on by the rise in the casein-to-moisture ratio. As a result, even minor changes in moisture content can have a big impact on how fresh cheese feels [17]. In addition to these, Ref. [18] examined how cheese's microstructure and texture are affected by its fat level. They explained that increase in fat content result in smoother and softer cheese, and increase in casein content result in firmer cheese. It was also revealed that higher fat and water contents tend to weaken the protein structure of the cheese, as well as its texture [19].

#### **Figure 1.**

*Compression curves of soft white cheese (SWC), made from camel milk, using different starter cultures: Compression values from a single replication are shown from the texture analyzer software. The STI-12 and RST-743 cultures were inoculated at 37°C, whereas R-707, XPL-2, and CHN-22 cultures were inoculated at 30°C.*

#### **2.4 Effect of starter cultures on sensory characteristics of camel milk cheese**

Cheese's sensory qualities are regarded as one of the key factors influencing consumer preference. The customer can detect a variety of cheese sensory qualities, which are commonly categorized under look, flavor, and texture. All of these characteristics influence cheeses' acceptability and eating quality. There are many different kinds of cheese around the globe, each having a different sensory character. It reflects the properties of the milk used to make the cheese, the cheese-making environment, and the physical and chemical alterations that take place during ripening [20]. Since cheese can come in a wide variety, numerous trials are required in order to offer consumers a wide range of products. Different cheeses based on the techniques for producing feta and halloumi [8], soft unripened [21], gruyere [22], and mozzarella [18, 23] were examined, but the finished product's texture, flavor, and taste did not match those of the bovine equivalent. In fact, when making cheese, the "proteiniclipidic matrix" of camels behaves differently from milk to cattle. To comprehend the changes that occur during the various steps of acidification, coagulation, draining, brining, and refining as well as the impact of different starters and thermal treatments, such discrepancies between milk from different dairy species require more fundamental investigations of rheological properties.

With the exception of color preferences, it was reported, using a different starter culture affects test results for consumer preferences. In comparison with camel milk SWC made using STI-12, RST-743, and R-707 cultures, camel milk soft cheese made using XPL-2 and CHN-22 cultures received higher scores for flavor (aroma and taste). The similar outcome was discovered, showing that starter culture-prepared cheese samples were preferred over cheeses made through direct acidification with citric acid in terms of look, flavor, and texture [24]. The starting cultures XPL-2 and CHN-22's natural abilities to produce aroma molecules like diacetyl may be the cause of the flavor variances. When citrate is co-fermented with lactose to make various kinds of cheese, lactic acid bacteria, particularly *Lactococcus lactis biovar diacetylactis*, naturally generate diacetyl [25]. The characteristics of the various commercial starter cultures utilized may be to blame for the variances in consumer preference test ratings in this study, particularly in appearance, scent, taste, and overall acceptability of the cheese samples. Additionally, substances including CO2, diacetyl, and acetaldehyde may have contributed to the cheese developing unique texture and flavor characteristics [25, 26].
