24-6

Broccoli is a major fresh market vegetable with good nutritional value that is difficult to store due to post-harvest defects including yellowing, loss of green color, mold growth, and loss of cell turgor.  Improvement in shelf life would benefit both military and civilian populations.

 

The objectives of this work were to develop post-harvest treatments that will prolong the shelf life of this crop.  Treatments tested included various modified atmosphere packaging films, temperature, absorbents, and growth hormones.  The growth hormone treatments included, gibberellic acid 4,7 (GA), benzyl adenine (BA), aminoethyoxyvinylglycine (AVG) and 1-methyl cyclopropene (MCP) as well as controls. Broccoli was evaluated for color, defects, firmness, edibility, total plate counts, and mechanical firmness. Oxygen, carbon dioxide and ethylene levels in packages were also monitored.

 

Broccoli stored in modified atmosphere packages exhibited less yellowing and mold growth resulting in a greater shelf life at all temperatures tested. Storing as close to 0° C as possible without ice formation leads to the longest shelf life. Both BA and GA delaying yellowing whereas AVG and MCP had no measurable effect.  The latter suggests that ethylene is not involved in the yellowing process with broccoli.

 

By using optimum conditions identified in this study, it would be possible to store broccoli for a month or more with good product outturn.