The apparent opacity (Yap) of the films was determined using a
colorimeter (BYK Gardner, USA) and was calculated based on the
ratio between the luminosity (L*) of the system (CIELab), which was
measured with a black background (LB) and a white background
(LW), and the thickness of the film (4). The results were expressed
on an arbitrary scale (0e100% mm1) according to Equation
The opacity of the films intercalated with fresh pasta was
determined after 2 and 37 days of storage at 10 C