บทคัดย่อ | : | This research aimed to study the
influence of cultivars and drying conditions on color, total phenolic compounds
and %DPPH of lotus leaves. Four
cultivars of lotus leaves: East Indian lotus, Hindu
lotus, Roseum
Plenum and Magnolia lotus were studied. The
lotus leaves were cut into 1*1 cm2 and dried in
hot air oven at 60, 80 and 100 oC
until the samples had 3% moisture content.
To reach 3% moisture content, the lotus leaves were dried at 60, 80 and
100 oC for 4 hr, 3 hr and 40 min, respectively. It was found that cultivars and drying
conditions had significantly
effect on color and antioxidant capacity of lotus leaves. Drying lotus leaves at 60 oC yielded highest L*, a* and b* value in
all cultivars. L* and b* value of Roseum Plenum, Magnolia
lotus and
Hindu lotus leaves were not significantly different and were higher than East
Indian lotus leaves. East Indian lotus
leaves had highest green a* value.
Drying lotus leaves of 100 oC
yielded highest total phenolic compounds but lower %DPPH radical scavenging
capacity in all cultivars. At 60 oC, cultivars had no effect on total
phenolic compounds but had significantly effect on %DPPH radical
scavenging capacity.
East
Indian lotus leaves had the highest %DPPH
radical scavenging capacity and Hindu lotus leaves had the lower value. The result of color and antioxidant capacity
showed that drying East Indian lotus leaves at
60 oC was the best
condition. |