2.4. Water solubility (WS)
WS was defined as the percentage of film dry matter that was
solubilized after 24 h of immersion in distilled water (Gontard
et al., 1994). The initial dry matter (%) was determined gravimetrically
by drying 2 2 cm2 film samples (about .16 g) at 103 ± 2 C
for 24 h. The same films (2 2 cm2) were then immersed in