TOTAL ANTHOCYANIN CONTENT AND ANTIOXIDANT ACTIVITY IN FRUITS OF RASPBERRY (Rubus idaeus L.) AT DIFFERENT DEGREES OF RIPENESS

Abstract

The degree of ripeness of berries is associated to their anthocyanin content. The objectives of this study were to determine the effect of location and degree of ripeness on the anthocyanin content and antioxidant activity of raspberry fruits. We used the variety ‘Autumn Bliss,’ grown in Tlamimilolpa, Hidalgo and in San Mateo Acatitlan, Mexico. The degree of fruit ripeness was established by their pink (GM1), red (GM2) and red (GM3) coloration. The variables evaluated were: moisture (by difference in weight), color (Hunter-Lab), total anthocyanin content (CTA) using a colorimetric conventional method, and antioxidant activity (AA) by the DPPH radical method. The degree of fruit ripeness affected their color, total anthocyanin content and antioxidant activity. Location influenced anthocyanin content in degrees of ripeness GM1 and GM2, but not in fruits from GM3. Antioxidant activity of fruits with GM1 and GM2 degrees of ripeness was lower than that observed in GM3 ones. According to these results, to optimize the beneficial effect of raspberry consumption, fruits should be consumed when they show an intense red coloration (GM3).