CHLOROPHYLL STABILITY DURING CONTINUOUS ASEPTIC PROCESSING AND STORAGE

Spinach puree was aseptically processed and packaged at four time-temperature treatments (19.2 and 5.3 sec @ 142-degrees-C; 19.2 and 12.2 sec @ 137-degrees-C). Samples processed at 142-degrees-C for 5.3 sec retained 68% of total chlorophyll compared to blanched samples while all chlorophylls were degraded in retorted product. The rate of chlorophyll b degradation and pheophytin b formation during storage in flexible containers at 4, 25, and 40-degrees-C fit a first order kinetic model. Apparent activation energies during storage for each time-temperature treatment ranged between 11.1 and 14.3 kcal/mol. Analyses of degradation products indicated oxidation during storage was not a dominant factor in chlorophyll conversion and color loss.