Shelf-life extension of cottage cheese by modified atmosphere packaging

The effectiveness of flushing headspace of commercial packages of cottage cheese with pure carbon dioxide on shelf-life extension was evaluated. An optimum headspace of about 25% (v/v) in 250 mL packages, flushed with pure CO₂, extended shelf-life of cottage cheese at 8 °C by about 150% without altering sensory properties or causing any other negative effect. Flushing of headspace with pure CO₂ caused dissolution of about 8 mmol/kg CO₂ which gave additional protection, besides good sanitation, against spoilage bacteria, yeasts and moulds. In order to maintain the proper CO₂ level in headspace and cause its dissolution into the product the use of high barrier packaging materials is essential.