The acid-base buffering properties of Alxa bactrian camel milk

- The buffering of milk influenced many of its physico-chemical properties, by controlling pH during processing.
- There were many reports on the buffering of milk and of cheese, calculated from titration curves.
- However, the titration curves obtained depends on the methodology used, the forward and back titration curves of milk did not coincide.
- The buffering properties of camel milk was investigated by the forward and back titration.
- The results had shown that the forward and back titration curves were not identical, the camel milk had stronger buffering capacity than that of bovine milk.

The buffering properties of Alxa bactrian camel whole milk was investigated by titrating with base or acid. A “loop” was observed in the pH range 6.6-4.3 when sample was firstly titrated with acid and then back titrated with base. A “loop” was not observed when sample was firstly titrated with base and then back titrated with acid. When the milk sample was titrated from initial pH to 2.0 with HCl, camel milk exhibited a pronounced maximum buffering at approximately pH4.4 and the value of dB/dpH was about 0.073. When acidified camel milk sample was back titrated from pH 2.0 to 11.0 with NaOH, there was low buffering index at approximately pH 4.9 (0.024), and maximum buffering index occurred at approximately pH 6.1 (0.051). The sample was firstly titrated from initial pH to 11.0 with NaOH, camel milk exhibited a weaker buffering peak at approximately pH 7.1 and the value of dB/dpH was about 0.018, when the alkalized milk sample was back titrated from pH 11.0 to 2.0 with HCl, the maximum buffering index occurred at approximately pH 5.1 and the value of dB/dpH was about 0.047.