I want to measure the fat destabilization rate in ice cream with a spectrophotometer. For the absorbance of the mix, should I measure it soon after preparing the mix, or after pasteurization, or after ageing?

Method:

Diluting: 1 g ice cream 1/500

Centrifuging: 1000 rpm 5 min

Measurement: 10 min later, at 540 nm

Fat destabilization rate %= [(Amix-Aicecrem)/A mix]x100

Amix: The absorbance of the mix

Aice cream: The absorbance of the ice cream