Respiratory and colour characteristics of alfalfa chops at 14 and 20% moisture contents and 8 and 23degreesC storage temperatures under modified atmosphere packaging (MAP) and non-MAP conditions in sealed polyethylene packages with and without specific gas mixture (1% O-2, 5% CO2 and 94% N-2) were studied. The study indicated that an increase in storage period caused a proportional decrease in percent oxygen in the packages, thereby reducing the respiration rate of alfalfa chops under the MAP environment. Further, the samples stored at 23degreesC and without the MAP environment had a fungal growth and the colour of the samples was not as green as those kept at a temperature of 8degreesC. (C) 2002 Silsoe Research Institute. Published by Elsevier Science Ltd. All rights reserved.