Effect of dehydration methods on retention of carotenoids, tocopherols, ascorbic acid and antioxidant activity in Moringa oleifera leaves and preparation of a RTE product.

Fresh leaves of M. oleifera plants were analysed for
nutritionally important phytoconstituents and feasible commercially
used dehydration method were evaluated to preserve
these in dehydrated leaves. Trans-lutein, trans-β-carotene
and trans-zeaxanthin were found as the major carotenoids
in fresh leaves, accounting for 36.9, 18.2 and 5.5 mg/100 g
FW, respectively. Similarly, high amounts of ascorbic acid, α-
tocopherol and total phenolic content (271.0, 36.9 and
512.0 mg/100 g FW), respectively were recorded in leaves.
α-tocopherol was the most stable vitamin under all drying
conditions (86.4 % retention during oven drying), compare
to other studied phytoconstituents. Cabinet tray drying was
found as efficient as lyophilisation to retain maximum content
of total carotenoids (60.1 %), trans-β-carotene (90.1 %), 13-
cis-lutein (93.2 %), and DPPH activity, however, lutein
(51.3 %) and ascorbic acid (97.8 %) was best preserved by
lyophilisation. During dehydration, significant trans to cis
isomerization of β-carotene and lutein was also recorded. A
ready to eat (RTE) chutney powder (adjunct) was developed
from dehydrated leaves. The product was evaluated using
Quantitative Descriptive Analysis and was accepted with a
high overall quality score. The present investigation explores
the nutritional potential of M. oleifera leaves and suitable
methods of drying that could be useful for processed food
formulation.