METHYL JASMONATE EXTENDS SHELF-LIFE AND REDUCES MICROBIAL-CONTAMINATION OF FRESH-CUT CELERY AND PEPPERS

During a study of the ameliorative effects of methyl jasmonate (MJ) on chilling injury to vegetables, a decrease in the rate of deterioratio n of treated fresh-cut segments was noticed, along with an apparent de crease in microbial growth. This study showed that MJ vapor from a 10( -4) or 10(-5) mol source in a 1 L container retarded deterioration of celery sticks for 2 weeks at 10 degrees C. The number of bacterial col onies was reduced to 1/1000 of control after 1 week of storage. A MJ e mulsion applied as a dip at 10(-4) or 10(-5) mol/L retarded deteriorat ion of green pepper strips for 2 weeks at 10 degrees C. The number of bacterial colonies was reduced to 1/1000 of control also after 1 week of storage and, in particular, the appearance of son rot was retarded by the jasmonate treatment. Measurement of the amount of MJ vaporized during storage was done by use of a [H-3]jasmonate internal standard. Less than 1 x 10(-6) mol of MJ vapor was necessary to cause the bioche mical changes in the stored vegetables resulting in prolonged storage life and decreased microbial growth.