Thermal kinetics of pungency loss in relation to the quality of pickled garlic

The kinetics of the loss of pungency (enzymatically formed pyruvate) from garlic slices during heating was investigated at selected temperatures (60, 65, 70 and 75 °C) with the aim of optimizing the water blanching treatment in the processing of pickled garlic. For each temperature, after a lag period, pungency appeared to decrease in two phases as heating progressed. The first and more important phase, which was used for the calculation of the kinetic parameters, followed first‐order kinetics. The calculated z‐value (9.4 °C) was significantly lower than z‐values generally reported for degradation of quality factors in foods. The effectiveness of thermal treatment to eliminate pungent flavour and inhibit green discolouration increased with increasing temperatures. Optimum blanch treatment was reached at 80 °C for 1.1 min. Pyruvate determination was shown to be a better indicator of pungency than allicin determination in blanched garlic slices.