• Calcium chloride;
  • firmness;
  • optimization;
  • pectins;
  • puncture force

Diced green bell pepper was blanched twice, once at 51–79 °C for 19–61 min, and once at 95 °C for 3 min, and dried. The firmness of rehydrated samples was measured by puncture, and optimum conditions assessed by response surface methodology. The optimized model showed that, blanching at 65 °C for 49 min gave a 64% increase in puncture force over the control. The optimum temperature was used to evaluate the effect of adding CaCl2. The dices were blanched twice, once at 65 °C for 3 min in either 0 or 4% CaCl2, secondly in either 0 or 2% CaCl2 solution at 95 °C for 3 min. In the second case the dices had been held at room temperature for 0–30 min before treatment. Adding CaCl2 increased puncture force significantly (P ≤ 0.05). The best results, those which gave greatest firmness, were obtained by blanching at 65 °C for 3 min in 4% CaCl2, holding for 16 min after blanching, followed by a secondary blanching at 95 °C in 2% CaCl2.