Extending the shelf-life of asparagus spears with a compressed mix of argon and xenon gases

Noble gases that form clathrate hydrates when dissolved into water and restrict water molecule activity can prolong the shelf life of fruits and vegetables. Physiological and physical aspects of asparagus spears treated with mixtures of compressed (1.1 MPa absolute) argon (Ar) and xenon (Xe) (2:9 in partial pressure) were compared with controls under normal preservation in modified atmosphere packaging (5% O-2 and 5% CO2) and cold storage (4 degrees C). The bract opening and respiration rates of asparagus spears were reduced slightly after the Ar-Xe treatment. A clear reduction between the compressed air and compressed mixture of Ar and Xe was only observed on the 6th and 15th days of storage for the bract opening rate and the 15th day of storage for the respiration rate. The climacteric peak was comparatively inconspicuous. The increase of crude fiber was reduced and both vitamin C and chlorophyll preserved. Based on comprehensive evaluation, asparagus spears treated for 24h with mixtures of Ar and Xe could be kept in good quality for 12 days at 4 degrees C. (C) 2007 Published by Elsevier Ltd. on behalf of Swiss Society of Food Science and Technology.