ศูนย์นวัตกรรมเทคโนโลยีหลังการเก็บเกี่ยว

Effect of pretreatment and conditions and period of storage on some quality indices of frozen chive (Allium schoenoprasum L.).

Kmiecik, W. and Lisiewska, Z.

Food Chemistry. Volume 67, Number 1, Oct 1999. Pages 61-66 .

1999

บทคัดย่อ

Chive leaves for freezing contained 13.9 g dry matter, 133 mg vitamin C, 4.7 mg beta carotene, 121 mg chlorophylls (a + b), 40.4 mg nitrates, and 0.19 mg nitrites in 100 g of edible parts. Blanching of the raw material before freezing reduced the level of dry matter by 22%, vitamin C 29%, beta carotene 20%, chlorophylls 21%, and nitrates 26%, while that of nitrites increased three times. Freezing and 12-month storage of frozen material caused further losses in the analysed constituents except dry matter. Losses were distinctly higher on freezing non-blanched chive, a further enhancement of losses being observed with a storage temperature at -20 degrees C. After a 12-month storage of frozen chive, the preserved content of vitamin C ranged from 11 to 66%, beta carotene 37 to 65%, chlorophylls 65 to 75%, and nitrates 58 to 81%. If the blanching is omitted and the storage temperature is -20 degrees C, a good preservation of vitamin C is not possible even for a period of 3 months. In contrast, the pretreatment of blanching ensures its good preservation at -20 degrees C and at -30 degrees C, and also yields a very good conservation of all the constituents analysed.