The effect of temperatures (0, 2, 5, 7 and 10°C) for 14 days of storage on antioxidant constituents such as vitamin C and phenolic compounds of artichoke c.v. ‘Blanca de Tudela’ was studied. Three groups of phenolics were identified and quantified as: chlorogenic acid; 1,5-dicaffeoylquinic acid (1,5 di-CQA)+3,5-dicaffeoylquinic acid (3,5 di-CQA); and 1,4-dicaffeoylquinic acid (1,4-di-CQA)+4,5-dicaffeoylquinic acid (4,5 di-CQA). The content of vitamin C was higher in the internal bracts compared with the external ones (144 and 193 mg kg−1 fresh wt., respectively) and decreased after 14 days of storage under the assayed temperatures. Each individual group of phenolics was 10-fold higher in the internal bracts than in the external ones. At harvest, total phenolics (618 mg kg−1), chlorogenic acid (143 mg kg−1) and 1,4 di-CQA+4,5 di-CQA (207 mg kg−1), increased in internal bracts after storage, particularly at 2, 5 and 7°C. On the other hand, 1,5-di-CQA+3,5-di-CQA decreased from 260 to 150 mg kg−1 after storage. Consumption of the edible artichoke fraction could be an important source of natural antioxidants and provide significant nutritional value to the diet.

The authors are grateful to the Spanish CICYT for their financial support of this work ŽALI98-0843, 95-0297-OP. AGI thanks the Spanish MEC for their pre-doctoral grant.

4 pages, 3 figures.

Peer reviewed