Texture and antioxidant evolution of naturally green table olives as affected by different sodium chloride brine concentrations

The results on the evolution of the texture and antioxidant activity during the processing of naturally fermented green olives are reported in the present study. The olives were brined with two different NaCl concentrations, 4 and 7%. A puncture test and a texture profile analysis (TPA) test were carried out to evaluate texture, while the antioxidant activity was assessed in consideration of the loss of absorbance of a stable radical upon reaction with a polyphenolic olive extract. The puncture test revealed both an increase and decrease in peel and flesh hardness, respectively. The olives processed with 7% NaCl concentration showed higher peel hardness than olives brined with 4% salt. The texture profile analysis did not reveal any difference between the two salt concentrations used, but showed a decrease in the value of all parameters after 30 days of brining. The antioxidant activity of the polyphenolic extract decreased significantly during processing, with a major loss after the first 30 days of processing and was higher in the 7% brined olives, than the sample treated with 4% NaCl.