In this research paper we studied the effect of some thermal treatments on chlorophyll, carotenes and xanthophylls content from spinach and savoy cabbage leaves. Were analysed fresh samples and samples blanched (approx. 98 °C for 5 min), boiled (20 min) and frozen after blancing prior (at approx. 18 °C for 2 months). The concentrations of chlorophyll and carotenoids were determined spectrophotometrically. Of the two analyzed vegetables, spinach had the highest concentration of chlorophyll (total chlorophyll 515.47 mg/g- for fresh spinach, respectively 289.07 mg/g- for fresh savoy cabbage. The more aggressive thermal treatment, in terms of the reduction of the chlorophyll concentration in both vegetables was boiled, followed by freezing. Blanching resulted in the lowest losses of chlorophylls. After the thermal treatments applied, the most significant losses for both the spinach and savoy cabbage, have been recorded for the chlorophyll "b". From experimental data it was observed that spinach is richer in carotenoid compounds than savoy cabbage (total carotenoids in fresh spinach: 98.17 µg/g, fresh savoy cabbage - 72.46 µg/g). The most important loss of carotenoids, both in the case of spinach and savoy cabbage leaves, occur after boiling, and the lowest losses recorded after blanching. Boiling led to the loss of carotenoids higher for cabbage (34.45%) than for spinach (24.78%). Blanching and freezing after preliminary blanching caused higher losses of carotenoids in spinach than in cabbage.
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