Color Changes of Fresh-cut Swiss Chard Leaves Stored at Different Light Intensity
In this study, the effect of continuous and periodic-light treatments on colour retention of freshly cut chard was investigated. Light sources were day light-fluorescent lamps of 1300 lux. The lamps were placed 70 cm above the samples in a cold room set-at 5°C temperature and 85-90% Relative Humidity (RH). One experimental group (L) was constantly exposed to light, another group (PL) was exposed to light for 15 min per hour. Control group (D) of samples was not exposed to light and was stored in the dark. All experimental groups were stored for 14 days. Leaf yellowing, measured by both hue angle and b values, was greater in the continuous light treatment (Group L) compared with the PL and D treatments at the end of the storage. Also, chlorophyll content of samples in L treatment was lower than PL and D treatments at the day 14. The chard leaves in the L and PL groups showed greater weight-loss when compared with the control group (D) both 7th and 14th d of storage so, the continuous light treatment increased weight-loss. The brightness (L* value) of the samples, increased in both the L and PL treatments compared with the D treatment at the end of the storage.