Changes in ascorbic acid, beta‐carotene and sensory properties in Sundried and stored Amaranthus hybridus vegetables

Abstract

maranthus hybridus was grown as a leafy vegetable in Dar‐Es‐Salaam, Tanzania. Freshly harvested leaves were analyzed for moisture content, beta‐carotene and reduced ascorbic acid. The leaves from the four sites were bulked, blanched and sundried with shade provision drier. The dried samples were stored in polythene bags at 22°C, 28°C and room temperature (30°C to 32°C). At the beginning and thereafter every month during storage, the vegetables were analyzed for beta‐carotene and ascorbic acid and subjected to sensory evaluation in comparison with fresh cooked leaves.

Sundrying of the amaranth leaves resulted in significant reductions (P < 0.05) in the levels of ascorbic acid and beta‐carotene, of 87.4% and 16.3% respectively. After storage of the dried vegetables for three months, the retention at 22 ° C, 28 ° C and room temperature of ascorbic acid and beta‐carotene were 42, 40 and 36 mg/100g and 32.4, 29.5 and 27.4 mg/100 g dwb respectively. Sensoric quality evaluation of amaranth leaves showed that significant differences (P < 0.05) existed in appearance and colour, flavour, texture and overall acceptability, although the dried vegetables were still acceptable in all the sensory characteristics tested. The study established that the vegetables could be dried to produce an acceptable product which maintained its eating quality for up to three months in storage.