Effect of visible light treatments on postharvest senescence of broccoli (Brassica oleracea L.).
BACKGROUND
Broccoli (Brassica oleracea L.) is a rapidly perishable vegetable crop. Several postharvest treatments have been applied in order to delay de-greening. Since light has been shown to have an effect on pigment accumulation during development and darkness is known to induce senescence, the effect of continuous and periodic exposure to low-intensity white light at 22 °C on postharvest senescence of broccoli heads was assayed.


RESULTS
Exposure to a constant dose of 12 micromol m(-2) s(-1) was selected as the most suitable treatment and was employed for subsequent experiments. During the course of the treatments, hue and L* values as well as chlorophyll content and visual observation of florets indicated an evident delay in yellowing in treated samples compared with controls. No statistically significant differences in total protein content were found, but soluble protein content was higher in treated samples. Total and reducing sugar as well as starch levels decreased during postharvest senescence, with lower values in control samples.


CONCLUSIONS
The results of this study indicate that storage under continuous low-intensity light is an efficient and low-cost treatment that delays postharvest senescence while maintaining the quality of harvested broccoli florets.
Instituto de Investigaciones Biotecnológicas, Instituto Tecnológico de Chascomús (IIB-INTECH), UNSAM-CONICET, Camino Circunvalación Laguna Km 6, (B7130IWA) Chascomús, Buenos Aires, Argentina.
Agustin M
AM
Büchert
Maria E
ME
Gómez Lobato
Natalia M
NM
Villarreal
Pedro M
PM
Civello
Gustavo A
GA
Martínez
D001937:Brassica / Q000737:chemistry*; D016922:Cellular Senescence; D002734:Chlorophyll / Q000032:analysis*; D003116:Color; D004040:Dietary Carbohydrates / Q000032:analysis*; D004044:Dietary Proteins / Q000032:analysis*; D035264:Flowers / Q000737:chemistry; D005511:Food Handling; D008027:Light
D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D002734:Chlorophyll