Gelling test during acidification

This test measures the capacity of a protein to form a gel when it is gradually acidified. A weak acid (glucono-δ-lactone) is added to the protein solution. The evolution of pH is measured during 3h and in parallel the evolution of the « solid » and « liquid » behaviour of the solution is measured (elastic and loss modulus). Protein gelling with acidification are used for dairy alternatives such as chess and yoghurts.