Total phenolic content increased between 60 and 180 d of
storage and then after 360 d decreased to a similar value obtained
the beginning of storage (Fig. 3B). However, during all the storage
period no significant differences were detected between samples
pasteurized and unpasteurized (Table 1). Asami et al. (2003) found
a 30% increase in the total phenolics of clingstone peaches after 3
months storage at 12 C. Freezing process may result in disruption
of the cellular matrix and more facilitated extraction of the phenolics.
Puupponen-Pimi€a et al. (2003) studied the effects of freezing
on phenolic compounds of peas, carrots, cauliflower, cabbage and
potatoes and they reported an average loss of 20e30% of total
phenolics in most vegetables, although no change was observed in
most carrot samples and a 26% increasewas observed in cabbage. In
the process of freeze-drying higher extraction efficiency of the total
phenolics can be obtained because it can lead to the development
of ice crystals within the plant matrix. Ice crystals can result in a
greater rupturing of plant cell structure, allowing better solvent
access and extraction