Quality of alfalfa cubes during shipping and storage

Deterioration of alfalfa cubes during shipment to markets in the Far East i s an important problem for alfalfa exporters in North America. This study w as initiated to examine the conditions that lend to quality losses in trans it. Commercially produced alfalfa cubes were exposed to constant temperatur e and relative humidity (rh.) conditions in sealed containers in two trials , one lasting 66 d and the other for 90 d. Temperatures examined ranged fro m 8 to 39 degrees C, and r.h. from 60 to 85%. Visible molding, color hardne ss, and density of cubes were monitored at regular intervals. The durabilit y of cubes was measured before and after storage. Changes in the physical c onditions of the cubes were modeled mathematically. The model predicting th e onset of visible molding was validated using temperature and rh. data fro m actual cube shipments to a Far East destination. The model correctly pred icted molding in 11 of 12 containers. Cubes stored at or below 16 degrees C and 70% r.h. remained free of visible mold for at least 90 d which was max imum test duration. Storage conditions in transit should not exceed these v alues, in order to ensure a high quality product for consumers in the Far E ast.