Abstract:
The effects of pH of film-forming solutions from unwashed silver catfish mince on
film formation, thickness, mechanical properties, water vapour permeability, colour,
light transmission, transparency, film solubility and biodegradability were
investigated. It was found that film from silver catfish mince had been successfully
formed at pH 1-4 and pH 9-12. The thickness, tensile strength, elongation at break,
water vapour permeability and film solubility were significantly different for films
obtained (p > 0.05). Higher thickness was obtained for the film prepared at pH 11
and pH 12. The study showed the resulting films had improved water vapour
barriers than other fish mince films. Tensile strength was found to be higher for the
films prepared at extreme pH region (pH 1, 2, 3, 11 and 12). The films formed gave
high value of elongation at break owing to the presence of weaker bond which
stabilized the film matrix. Higher pH of film-forming solutions with enhanced
dispersion capacity in water favoured higher film solubility. The biodegradability of
film showed the similar trend with film solubility. Nevertheless, pH of the film
forming solutions had no impact on colour of the silver catfish mince films. All
resulting films had excellent UV barrier properties at the wavelength of 200-280 nm
regardless of pH of the film-forming solutions. These films also showed low light
transmission at visible range (400-800 nm).
