The Quality Enhancement Of Agar Extracted From Gracilaria Verrucosa Cultured In Various Conditions Of Postharvest Periods

This study was aimed to evaluate the quality of agar extracted from the red seaweed, Gracilaria verrucosa upon postharvest culture treatments. After harvesting from the culture medium (0d), the seaweed were subjected to postharvest culture in the dark in salinity of 20 % (ambient) and 30% (salinity increased) for 3, 8 and 12 days respectively. Each treatment was in triplicate. Results indicated that 8d (20 %) and 3d (30 %) treatments had improved the agar content and reached approximately 40% more than harvested algae before postharvest treatments (0d). The gel strength had a significant increase in 3d and 8d of both 20% and 30%. The sulphate and ash content of the agar was lower in 3d (20%) and 8d (30 %) than others in each group and all treatments carried out in dark with salinity of 30% produced agar with lower water content when compare to dark with salinity of 20%. It indicates that postharvest treatments in general may perform good agar properties. Hence, the application of postharvest culture in the dark, either in ambient or increased salinity may reasonable to enhance the quality of G. verrucosa.

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