Effect of Gum Arabic on Enzymatic Coagulation of Camel Milk

Abstract

This study was carried out to determine the effect of Gum Arabic on enzymatic coagulation of camel milk with addition of each of calcium chloride and calcium phosphate separately .Camel milk was collected from ALAAS Farms at Khartoum North (Sudan). Gum Arabic was added at six concentrations 0.1 ,0.2 , 0.4 , 0.6 , 0.8, and 1.0% to whole fat fresh camel milk. Rennet was added at 0.4% (v/v). Calcium chloride and calcium phosphate were added at 0.3% (w/v). Results of chemical analysis of camel milk was as follow: protein 3.2%, fat 3.7%, lactose 3.28%, moisture content 88.77%, total solids, 11.3%, ash 0.65%, mineral contents mg/100g was, sodium 85, potassium 115, calcium 116 ,magnesium 19.6, iron 35.5, whereas phosphorus content was 24.5. Milk pH 6.5-6.7 and acidity 0.16-0.2%. When gum Arabic was added with calcium chloride to camel milk, milk coagulation time was 104.33, 70.67, 64.67, 60.67, 58.00, 50.67 and 40.67 minutes for control, 0.1, 0.2, 0.4, 0.6, 0.8, and 1.0% gum Arabic treated samples, respectively. There was a significant difference (P≤ 0.05) in milk coagulation time between control and gum Arabic treated samples and among gum Arabic samples, whereas 0.4 and 0.6 % gum Arabic treated samples were not significantly different. On the other hand when gum Arabic was added with calcium phosphate to camel milk, milk coagulation time was 72.33, 67.67, 61.00, 52.33, 48.00, 41.33, and 33.33 minutes for control, 0.1, 0.2, 0.4, 0.6, 0.8, and 1.0% gum Arabic treated samples, respectively. There was a significant difference (P≤0.05) in milk coagulation time between control and gum Arabic treated samples, and among gum Arabic treated samples. xiii Whole fresh cow milk was treated with gum Arabic at the same percentages as camel milk, with addition of calcium chloride and calcium phosphate for comparison. When gum Arabic was added with calcium chloride to cow milk, milk coagulation time was 10.33, 10.67, 7.67, 6.00, 5.33, 4.00, and 3.33 minutes for control, 0.1, 0.2, 0.4, 0.6, 0.8, and 1.0% gum Arabic treated samples, respectively. There was a significant difference (P≤0.05) in milk coagulation time between control and gum Arabic treated samples, and among gum Arabic treated samples, whereas control and 0.1% gum Arabic samples were not significantly different. When gum Arabic was added with calcium phosphate to cow milk, milk coagulation time was 19.00, 20.00, 18.33, 15.00, 7.67, 7.67 and 6.00 minutes for control , 0.1, 0.2, 0.4, 0.6, 0.8, and 1.0% gum treated samples, respectively. There was a significant difference (P≤0.05) in milk coagulation time between control and gum Arabic treated samples, and among gum Arabic treated samples , whereas 0.6 and 0.8% gum Arabic treated samples was not significantly different. Whey volume separated from camel and cow milk increases with increasing in gum Arabic concentration in case of calcium chloride and calcium phosphate addition.