Modification of the Physical Properties of Alginate with the Addition of Polymannuronate and Polyguluronate

Research Centre for Marine and Fisheries Product Processing and Biotechnology, Jakarta, Indonesia

^* Corresponding author: yono_ipn@yahoo.co.id

Abstract

Modification the physical properties of alginate using polymannuronate and polyfuluronate has been conducted. Polimannuronate and poliguluronate isolated from alginate with hidrochloric acid heating methods and precipitation based on pH, and the resulting product was characterized its viscosity. Polymannuronate and polyguluronate used to modify the functional properties of alginate from Sargassum crassifolium. Polymannuronate and polyguluronate were added and mixed into the alginate powder with a proportion of 0, 10, 20 and 30% (w/w). The results were then characterized the nature of the gel formulations which include gel strength, modulus of rigidity and syneresis. The results showed that the viscosity of the alginate used as a source polymanuronate and polguluronate of 162.89 + 3.66 cP. Polymannuronate and polyguluronate product has a viscosity respectively 85.00 + 5.90 cP and 100.44 + 2.27 cP. The addition of polymannuronate and polyguluronate into alginate produced the characteristic changes of the gel. The addition of polyguluronat tended to improve gel strength and modulus of rigidity, while the addition of polymannuronate tended to lower the gel strength with the same modulus of rigidity of alginate gel.