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Résumé :
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Two types of parsley were frozen and stored at temperatures of -20 and -30°C for 9 months. One half of the material was blanched before freezing and the other half was non-blanched. In 100g fresh leaves of Hamburg parsley there were 20.0g of dry matter, 310 mg of vitamin C, 7.5 mg of beta-carotene, 203 mg of chlorophyll, 30.8 mg N-NO3 and 0.078 mg N-NO2. For the leafy type the corresponding values were 17.3 g, 257 mg, 9.4 mg, 68.5 mg, and 0.077 mg. The material blanched before freezing showed significant losses in the contents of vitamin C (47-51%), nitrates (22-33%), and nitrites (43-55%) and distinctly smaller ones but also significant in the case of dry matter. During freezing and storage of frozen products there were losses in vitamin C, beta-carotene, and chlorophyll while the levels of nitrates and nitrites were variable. Particularly great losses of vitamin C and beta-carotene were observed in the non-blanched frozen leaves stored at -20 °C. After 9 months' storage, frozen products preserved 10-44% of vitamin C, 37-91% of beta-carotene, 78-95% of chlorophyll, and 78-153% of nitrates.
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