Abstract
The current study evaluated the potential of chitosan-based
melatonin (CH-MT)
composite coating to maintain quality and delay senescence of minimally processed
pomegranate aril-sacs
during refrigerated storage. Mature pomegranate fruit (cv.
Wonderful) without physical defects were processed into aril-sacs.
Subsequently, the
following treatments were applied; distilled water (control), CH 0.5% (w/v), CH+0.1 mM
MT, CH+0.4 mM MT, CH+0.8 mM MT, and CH+1 mM MT. Each treatment was applied
by immersing the aril-sacs
in the coating solution for 3 min and allowed to dry at room
temperature. Aril-sacs
were then packed in polyethene terephthalate punnets (three
to four aril-sacs/
punnet) and stored at 5°C and 85% RH for 21 days. Aril color, weight
loss, respiration rate, ascorbic acid content, total anthocyanins, browning index, and
antioxidant capacity were monitored during storage at 3 days intervals. The study results
showed that the CH-MT
coating treatments significantly (p < 0.05) delayed the
increase in aril-sacs
weight loss and respiration rate. These treatments also retained
higher aril chroma, ascorbic acid, anthocyanin content, DPPH-radical
scavenging activity,
and aril-sacs
antioxidant power (FRAP). In addition, surface browning development
was significantly suppressed in the coated aril-sacs
compared with control sacs.
However, the effectiveness of CH-MT
treatments in maintaining the quality of aril-sacs
was concentration-dependent,
with CH+0.8–1
mM MT treatments showing the
best results. Therefore, CH+0.8–1
mM MT treatments are recommended to suppress
the development of physiological disorders and maintain the quality of minimally processed
pomegranate aril-sacs.