Evaluation of Heat Stability of Camel Milk (Sterilized and Nonevaporated)

Abstract

The study evaluated the thermal stability of sterilized camel milk. The sterilized product was obtained from raw milk containing 9.11 ± 0.57% nonfat solids and 2.83 ± 0.45% fat. Disodium/dipotassium hydrogen phosphate (Na₂HPO₄ or K₂HPO₄), sodium citrate (SC), ethylenediaminetetraacetic acid (EDTA, disodium), sodium chloride (NaCl), and gum arabic (GA) were evaluated for their effects as thermal stabilizers of camel milk (CAM). Stabilizers were separately added to pasteurized camel milk (pH 6.67) followed by the in-container sterilization (115°C, 20 min). Phosphate salts afforded thermal stability (sediment test) when added to camel milk at 13 mM final concentration. During storage for four weeks at 21°C, the pH values of stabilized camel milk were 6.40−5.67, depending on the type and concentration of stabilizers. While nonstabilized (control) CAM showed substantial sediments during storage periods at ambient conditions (21°C), stabilized and sterilized CAM had no sediments reflecting one of the good quality characteristics (no sediments) of CAM. Color changes (ΔE^∗) in stored sterilized camel milk were below 2.3. It could be concluded that nonevaporated CAM could be made from CAM stabilized with Na₂HPO₄ or K₂HPO₄. This is the first study on the thermal stability of nonevaporated camel milk.