Water solubility of the films was determined following the method of Romero-Bastida et al. (2005). Briefly, pieces of films
from each formulation were cut uniformly (2 3 cm) and were conditioned in a desiccators containing silica gel (0% RH) for 7 days. Prior to the test, samples were weighed to a nearest weight of 0.0001 g. Followed by this, samples were dispersed into test beakers containing deionized water (80 ml). The samples were tested at room temperature (25 C) and maintained under constant agitation for 1 h. After soaking, the remaining pieces of films were filtered through filter paper (Whatman No. 1). Next, the samples were dried in an oven at 60 C until constant weight was achieved. All the samples were measured in triplicates with the percentage of total soluble matter (% solubility) being calculated using the formula: