4. Conclusions
Active packaging systems, OS/EE/high barrier packaging, successfully prolonged shelf life of sponge cake to at least 42 days without direct addition of chemical additives into the batter. The initial O2-scavenging rate, ability to maintain low O2 concentration through storage, and the presence of ethanol, play important roles in delaying microbial growth. OS retarded lipid oxidation and color change while EE delayed hardening of the cake. The established data will also be useful as a model for extending shelf life of other perishable products with a similar complex nature. Nevertheless, the future study on the mechanism underlying anti-firming effect of EE should be investigated.