ABSTRACTThermal degradation of chlorophylls and chlorophyllides in spinach puree was studied from 100 to 145°C (2–25 min) for chlorophylls and from 80 to 115°C (2.5–39 min) for chlorophyllides. The derivatives formed were: pheophorbides, pyropheophorbides, pheophytins and pyropheophytins. Degradation kinetics of chlorophylls and chlorophyllides followed a first‐order kinetic model. Reaction rate data showed that theaform of both chlorophylls and chlorophyllides degraded more rapidly than thebform. Chlorophyllides were less stable than chlorophylls. Activation energies ranged from 15.0 to 22.8 Kcal/mol. A kinetic compensation effect was observed for both chlorophylls and chlorophyllides with an isokinetic temperature of 160.8°C. The relative stability of these compounds suggests that methods to maximize chlorophyllides would not be effective for improving green color s
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