Table 1. A summary of studies to overcome the yogurt processing from camel milk (CM) by altering the milk composition and optimize the processing conditions

No. Objective of study CM fortification Optimization of processing conditions Key findings/results References
1 To assess the impact of added casein, whey protein, CaCl2, hydrocolloid gum, gelatin, sodium alginate and pectin on the quality characteristics of CM yogurt. CM supplemented with various additivesCN (1%–3%)WP (1%–3%)CaCl2 (0.1%–0.3%)GA (0.05%–0.15%GL (0.2%–0.4%)ALG (0.1%–0.3%)PC (0.1%–0.3%). Pasteurization at 85°C for 30 min.Add (0.05%) starter culture and incubate at 43°C for 12 h. CM yogurt obtained with the addition of whey protein and casein alone or in combination with pectin alginate showed better quality and consumer acceptability. (Sobti et al., 2020)
2 To evaluate the gelation and sensory attributes of CM yogurt by using food grade additive formulations. CM fortified by addition of sugar (5 g), gelatin (4 g), SMP (50 or 70 g) and starch (12 g) in 1 liter of milk. Pasteurization of mix at 85°C for 30 min and cooled at 45°C.Addition of chymosin (20 and 40 IMCU L–1) Addition of starter culture (3%) and incubate for fermentation. The sensory attributes of CM yogurt were improved by addition 7% SMP.The gelation properties of CM was improved with the addition of chymosin enzyme. (Benkerroum et al., 2022)
3 To analyze the impact of graded level of bovine milk supplementation on quality characteristics of CM yogurt. Fortification of CM with bovine milk at the level of (0%, 10%, 20%, 30%, 40%, 50% and 60%, v/v). Both milks were subjected to pasteurization at 85°C for 5 min, then cooled at 42°C.Adding (0.2%) commercial starter culture and incubate for fermentation up to 24 h. Results indicated that the addition of CM with BM (10%–60%, v/v) was negatively affect the coagulation behavior leading to weak gel formation. (Kamal-Eldin et al., 2020)
4 To examine the influence of graded level of monk fruit sweetener on the physicochemical properties and microbiological counts of drinking yogurt made from CM. CM fortified by 0, 0.42, 1.27, and 2.54 g/L of monk fruit sweetener. CM was reconstituted from powder.Pasteurization of yogurt mix at 82.2°C for 30 min and cooled at 40°C.Add 2.4 mL of fresh thawed starter culture and allowed for fermentation at 40°C. Results showed that the addition of monk fruit with CM effectively reduce the pH and enhance the viscosity of yogurt. The color and sensory quality were also improved. (Buchilina and Aryana, 2021)
5 To investigate the partial replacement of CM with oat milk on physicochemical, antioxidant, sensory and microbiological properties of CM yogurt. Milk used in this study was fortified with 2% dried whey protein concentrate (DWPC).Addition of CM with various level of oat milk (10%, 20%, 30%, and 40%). Yogurt mix was homogenized at 55°C–60°C for 2 min.Pasteurization of mix at 85°C for 30 min and cooled at 42°C.Add starter culture (5%) and allowed for fermentation at 42°C for 6–8 h. CM yogurt produce with the replacement of oat milk have superior rheological, sensory and antioxidant properties. (Atwaa et al., 2020)
6 To investigate the synergistic effect of trisodium citrate and microbial transglutaminase (mTGase) on the textural properties of CM gels. CM supplemented with various concentration of trisodium citrate and microbial transglutaminase. Prepared reconstituted CM and fat was removed by centrifugation.Add trisodium citrate (0, 10, 20, 30, and 40 mmol/L).Add mTGase (0, 10, 20, 30, and 40) to the yogurt mix.Incubate the samples at 43°C for 4 h. Adding trisodium citrate (30 mmol/L) to CM significantly improved the textural properties of the gel.Moreover, trisodium citrate induce chelating effect and dissociated the casein micelles leading to produce stable gel. (Chen et al., 2019)
7 To evaluate the effect of various level of passion fruit juice on fermentation, physicochemical and functional properties of CM set type yogurt. Reconstituted CM fortified by supplementing various levels of passion fruit juice (0%–10%) along with table sugar. Reconstituted CM were mixed with 6 g of sugar and subsequently subjected to homogenization.Pasteurization of yogurt mix at 90°C for 10 min and cooled at 42°C.Add starter culture (0.1%) followed by incubation to complete the fermentation process. Results indicated that passion fruit juice improves the gel strength and enhance fermentation process at early stage.The sensory quality of yogurt (aroma and flavor) were also improved.Moreover, the antioxidant capacity of yogurt was improved owing to the production phenolic compounds. (Ning et al., 2021)
8 To study the impact of mixed starter culture with supplementation of pectin (0.1%–0.3%) or sodium alginate (0.1%–0.5%) on sensory, structural and rheological properties of CM yogurt. CM supplemented by two hydrocolloids including pectin (0.1%–0.3%) and sodium alginate (0.1%–0.5%). Pasteurization of yogurt mix at 85°C for 30 min.Add (0.05%) mix starter culture and incubate at 43°C for 12 h. Yogurt supplemented with intermediate level of pectin or sodium alginate have better consistency and palatability. (Sobti et al., 2021)
9 To evaluate the impact of different level of plant seed gum (0%, 0.1%, and 0.2%) as the stabilizer on flow behavior, textural and sensory quality of CM frozen yoghurt. Standardization of camel and cow milks using skim milk powder and addition of different levels of plant seed gums. Milk was heated at 85°C for 30 min and cooled to 42°C, then inoculated the commercial yoghurt culture and allowed for fermentation up to 4 h, than store at refrigerated temperature. Supplementing plant seed gum significantly influenced the viscosity, melting rate textural and sensory quality of frozen yoghurt obtained from camel and cow milk. (Azari‐Anpar et al., 2021)
10 To study the impact of xanthan gum supplementation on quality attributes of CM yoghurt. CM supplemented with biosynthesize xanthan (0.25%, 0.50%, and 0.75%) as the stabilizing agent. Yoghurt mix was subject to pasteurization at 60°C for 30 min, then cooled at 40°C.Addition of 10% pasteurized date past in all treatment and mix the blend.Add 0.002% freeze dried culture and allowed for incubation at 43°C for 6–8 h. Results indicated that yogurt supplemented with biosynthesized xanthan at the level of 0.75% produce stronger gel.Additionally, 0.75% xanthan supplementation along with 10% date past improved the sensory quality of yogurt. (Mohsin et al., 2019)