Senescence of Broccoli Buds Is Related to Changes in Lipid Peroxidation

Chlorophyll (Chl), total soluble protein, lipoxygenase (LOX) activity, C₁₈ polyunsaturated fatty acid (PUFA), C₁₈ PUFA hydroperoxides, and total fatty acid declined and thiobarbituric acid-reactive substances (TBA-RS) increased in senescing broccoli flower buds during postharvest storage of broccoli florets at 5 °C over 96 h. The nonpackaged storage treatment resulted in a significant decrease in moisture, Chl, soluble protein, PUFA, and LOX activity and an increase in TBA-RS. Modified atmosphere packaging (MAP) and automatic misting (AM) treatments maintained Chl and soluble protein. MAP and AM storage reduced losses in PUFA and LOX activity and also reduced increases in TBA-RS for up to 96 h of storage. Further analysis of the data showed that a correlation existed between deterioration indices and lipid peroxidation (LP) parameters and the changes in LP indices preceded Chl losses in senescing broccoli buds. These results indicate a relationship between changes in LP and broccoli bud senescence.