Oxygen absorbers in the packaging of bakery products

Bakery products are subject to deterioration, the shelf life often being limited to only a few days at room temperature. Mould spoilage is the largest microbial problem in high and intermediate moisture bakery products, its growth being influenced by water activity. Losses due to mould spoilage vary between 1-5% of products depending on season, type of product and method of processing. In summer, for example, warm and humid storage conditions are conducive to mould growth. Similarly, condensation in packaging, caused by wrapping before the product has been appropriately cooled, provides a perfect environment for spoilage.

Mould spores in the air mean that a product is easily contaminated, as well as being affected by equipment and through handling, one solution to preventing mould growth is to use preservatives or additives. Consumer trends towards natural foods have meant that other methods to extend a product shelf life are now being adopted.

Modified atmosphere packaging (MAP), despite being costly to set up, is widely used to try and restrict spoilage. With this technique it is still difficult to remove all oxygen (O₂) completely and to obtain gas tight seals. Carbon dioxide (CO₂) and nitrogen (N₂) are the most commonly used gases in gas packaging of bakery products. Carbon dioxide is soluble in water and fat, producing carbonic acid and lowering the pH of the product, resulting in changes in the flavour. Nitrogen is also very effective but only if the residual oxygen percentage is low, the antimicrobial effect may be lost if the headspace oxygen concentration increases by as little as 0.5 - 1 %.

Oxygen absorbers, however, naturally remove oxygen from the headspace in packaging and are widely used in Japan to restrain the microbiological deterioration of bakery products. The method has extended to other countries and many studies have been made and published illustrating its benefits. The mould free shelf life of a product can be dramatically extended using oxygen absorbers, white bread, for example, can last for up to 45 days with this method. Other examples include an extension of 3 to 14 days for pizza crust; 1 year storage for gluten-free bread and a shelf life extension of three times on gas packaged crusty rolls. Oxygen absorbers can be applied to many disciplines and are already used in the army, extending the mould free life of their ready-to-eat bread to up to 13 months! The sachets can also be used in conjunction with MAP to increase their efficiency, maintaining an oxygen free environment during the whole shelf life of the product.

Bioka Ltd. produces sachet-type oxygen absorbers based on the latest biotechnology. Consisting only of natural food grade components, they differ from the current iron-based absorbers, which are subject to customer misuse. Bioka sachets generate carbon dioxide, replacing the removed oxygen so maintaining package dimensions. Biokas absorbers allow natural and safe preservation of food's original taste and freshness, resulting in extended shelf life without preservatives or additives.

• Bioka oxygen absorbers
• Oxygen and food quality
• Benefits
• Applications
• Easy to use
• Safe