Shelf life extension of sponge cake by active packaging as an alternative to direct addition of chemical preservatives

• O2 scavenger (OS) and ethanol emitter (EE) extended sponge cake shelf life from 1 to > 42 days at 30 °C.
• Initial headspace O2 reduction rate greatly impacted microbial control of perishable cake.
• “Pink” O2 indicator could not be used to confirm good microbial control.
• For prolonged storage, OS minimize oxidation and EE retard staling of sponge cake.
• Adequate O2-scavenging capacity and high O2 barrier packaging maintained critical low O2.

To extend the shelf life of sponge cake by an O2 scavenger (OS) and an ethanol emitter (EE) as alternatives to chemical preservatives, sponge cake samples were packaged with an active packaging system and a high barrier pouch, polyvinylidene chloride (PVDC)-coated nylon or nylon. Effects studied included the initial rate of O2 reduction, total O2-scavenging capacity to maintain critically low O2 concentration through storage, and effects of ethanol on microbial growth and evolution of headspace CO2 and O2. Active packaging system effectively extended mold-free shelf life of preservative-free cake from ∼1 day (control) to more than 42 days. By significantly retarding microbial growth and activities, active packaging shifts the critical shelf life determination reaction to physicochemical deteriorations. OS retarded lipid oxidation and enhanced color stability of the cake. EE delayed staling. PVDC-coated nylon enhanced the efficiency of active packaging better than nylon. The combination of OS and EE synergistically delayed microbial spoilage as well as physical and chemical deteriorations. Application of active packaging systems is an effective alternative preservation technology for prolonging the shelf life of highly perishable sponge cake without the direct addition of chemical preservatives into the bakery formula.