Effect of blue and UV-C irradiation on antioxidant compounds during storage of Hawthorn (Crataegus mexicana)

Abstract

The aim of this research was to evaluate the effect alone or combined of blue and UV-C irradiation on bioactive compounds and antioxidant capacity of hawthorn during storage. Hawthorn was irradiated with blue light or UV-C light to determine treatment conditions for storage. Increase in total flavonoids (27 and 49%), phenolic compounds (17 and 10%), vitamin C (17 and 15%), and antioxidant capacity (4 and 16%) were obtained in hawthorn treated with blue and UV-C light, respectively, at irradiation lower doses. Under these conditions, individuals and combined treatments of blue and UV-C light was performed in hawthorn to evaluate the effect in color parameters, bioactive compounds and antioxidant capacity of hawthorn during 30days of storage. In all treatments with blue light it was observed a significant (p<0.05) reduction in Hue values, indicating an orange-red color development which may be associated to carotenoids and flavonoids synthesis in hawthorn peel. Bioactive compounds and antioxidant capacity increases during storage, however, irradiation effect decreases during the first five days. Total flavonoids treated with UV-C light plus blue light maintain the increase during the storage, although this increase did not present any significant effect on antioxidant capacity.