Effect of blanching, dehydration and storage on selected nutrients of carrot (Daucus carota L.) slices

Abstract

Ten kilograms (10 kg) of fresh carrot samples were purchased from fruits and  vegetable garden, D-line Area, Port-Harcourt city. The samples were cleaned, cut into slices, divided into 3 lots and treated as follows; blanched and dehydrated (BLD), unblanched dehydrated (UBD) and fresh carrot slices (control). All the treatments were packaged in thick gauge transparent polythene bag (0.02 mm) and stored on laboratory shelf for 120 days under ambient conditions (26.3oC, 77.4%). Proximate tests (moisture, crude protein, crude fat, ash, fibre and carbohydrates), vitamin A and selected minerals tests were done on fresh, blanched and unblanched dehydrated carrot slices. These same parameters were evaluated monthly except vitamin A and mineral contents that were tested initially and at the end of the storage period (120 days). Results showed that crude protein, ether extract, crude fibre and ash contents continued to decline significantly (p = 0.05) with storage time. Blanching, dehydration as well as storage affected the vitamin A content of dried carrot slices significantly (p = 0.05). Drying caused significant (p = 0.05) increase in mineral contents of carrot slices except phosphorus content which had no significant difference (p = 0.05). The mineral contents of stored carrot slices reduced significantly (p = 0.05), with the exception of phosphorus which  accumulated significantly (p = 0.05). The study showed that nutrients may still be available to the consumers of dried carrot slices especially when they are not stored for extended period as observed in the study.

Keywords: Carrot, storage, blanching, vitamin A, mineral.