For each sample, both the impact energy and the energy that
passed through the sample were measured. For this purpose, an
ED-500 pyroelectric UV detector (Gentec Electro-Optic Inc., Quebec,
Canada) connected to an energy meter (Gentec DUO-dual
Channel laser power meter, Gentec Electro-Optic Inc.) was used.
To calculate the percentage of penetration of the light transmitted
into the cell, the amount of energy that passed through a cell containing
milk was compared with the amount of energy transmitted
through an empty cell using the following equation