Effect of different new packaging materials on biscuit quality during accelerated storage

BACKGROUND: The effect of innovative multilayer packaging materials versus a standard one on biscuit quality was studied during accelerated storage at 25, 35, 45°C and 50% relative humidity for 92 days. Three different packaging materials were used: metalized orientated polypropylene (OPP)/paper (control); metalized poly-lactic acid (PLA)/paper; metalized OPP with ethylene vinyl acetate pro-oxidant additive (EVA-POA)/paper. EVA-POA additive is used to make the plastic layer biodegradable. Various quality sample parameters (moisture, water activity (aw), texture, peroxide value (PV), hexanal) were analysed during storage. Rate constants (k) and activation energies (Ea) of hydration reactions and hexanal formation were calculated. RESULTS: No remarkable differences in the evolution of primary and secondary lipid oxidation were observed among differently packed biscuits during storage. All samples maintained PV levels between 4 and 14meq O2 kg-1 oil. The product in flexible packaging with PLA reached the highest moisture and aw levels, but they did not significantly and adversely affect the other quality characteristics. CONCLUSION: The obtained results demonstrate that the new tested packaging materials were suitable for commercial biscuit storage, having similar performance and preservation effects on the overall product quality to those of the standard one. Furthermore, these results could make a contribution to the food industry, encouraging the use of packaging materials with a negligible environmental impact as an alternative to petroleum-based ones.