2019 ASHS Annual Conference

Broccoli (Brassica oleracea L.) is a cool season vegetable that originated in Mediterranean Europe. A member of the Brassicaceae family, per capita consumption of broccoli has dramatically increased in the United States from 1.4 pounds in 1980 to 7.1 pounds in 2017, totaling approximately 2 billion pounds for the latter year. Broccoli is highly perishable due to its high respiration rate and rapidly loses quality under inappropriate handling temperatures. The purpose of this study was to evaluate the effect of commercial hydrocooling (HY), forced-air cooling (FA) or slushed-ice cooling (SI) on the quality and shelf-life of two commercial broccoli cultivars (‘Marathon’ and ‘Eastern Crown’) grown in northeast Florida during the early spring season. Following HY and FA, the crowns were wrapped in plastic film bags; all treatments were stored in waxed, corrugated cartons at 1°C for 7 d (simulating commercial storage), then transferred to 5°C for 8 d (simulating retail handling). Comparing the compactness of the two cultivars using a subjective rating scale (1= most compact and 5=loose florets), ‘Eastern Crown’ was firmer during storage (1.3) compared to ‘Marathon’ (1.7) but using a texture analyzer there was no significant force difference between them (51.65 N and 50.86 N respectively). Furthermore, ascorbic acid and carotenoid contents were higher in ‘Eastern Crown’ (148.5 and 21.2 mg/100 g FW) than ‘Marathon’ (131.6 and 17.1 mg/100 g FW). ‘Marathon’ had less chlorophyll breakdown during storage, as shown by higher a* (green color), and higher moisture content and lower dry matter content than ‘Eastern Crown’. During storage (0, 7, 11, 15 days), there was a decrease in crown firmness, texture, overall quality, and color values (L*, a*, b*, h*) of the broccoli heads. There was a reduction in the ascorbic acid and chlorophyll contents, but carotenoid content varied over the time. Dry matter and moisture contents were not significantly different.The cooling treatment significantly affected head compactness during storage, where HY and FA wrapped crowns had less crown softening compared to SI, but no effect in nutritional composition or head color. HY or FA broccoli and wrapping can help growers reduce cooling costs and provide a more favorable product for retailers while eliminating the problem of melting ice during transport of SI broccoli to the market.