Effect of cooking on polyphenols and antioxidant activity of Araucaria angustifolia seed coat and evaluation of phytochemical and microbiological stability over storage

The objective of this work was to evaluate the effect of cooking on total phenolic content and antioxidant activity of the coat of pinhAo. Moreover, the dried powder, obtained after seed coat cooking and drying, was stored for 90days at 25 degrees C, and stability of polyphenols and antioxidant activity, as well as, growth of viable bacteria and fungi were evaluated. Results showed that polyphenol content was increased in the residue submitted to cooking from 25 to 51mgGAEg(-1). DPPH radical scavenging capability decreased from 93% to 88% after the heat treatment, and 2,2'-azino-bis(3-ethylbenzothiazoline)- 6-sulfonic acid radical scavenging was not affected. PinhAo seed coat did not present iron-chelating capacity. The coat from cooked seeds presented low growth of viable bacteria, but was suitable to yeast multiplication during storage period under ambient conditions. No degradation of phenolics and compounds with antioxidant activity was observed during the storage conditions.