Abstract:

Headspace gas chromatography was used to investigate the effect of cooking temperature and simulants on
toluene migration and barrier properties of biaxially oriented polyamide/cast polypropylene (BOPA/CPP) retort laminated
films. The results showed that the migration rate of residual toluene to four different stimulants was in the order: 5 g/100 mL
sodium chloride > 0.2 g/100 mL sodium glutamate > 10 g/100 mL sucrose > distilled water. With the increase in cooking
temperature and treatment time, the migration rate of residual toluene was gradually increased for all these stimulants.
High temperature and condiment simulant treatments led to an increase in the water vapor and oxygen permeability of the retort
laminated films. Infrared spectroscopic, differential scanning calorimetric, and scanning electron microscopic analyses showed that
high temperature, distilled water and sodium chloride treatment destroyed the internal structure of the membrane and decreased the
crystallinity and inter-molecular force, resulting in the loose structure, uneven membrane surface and distortion.

Key words: laminated films, cooking temperature, condiment simulants, toluene migration, barrier properties