Oscillatory rheological studies of two different sodium alginates. The studies were conducted on two different alginates (F
g = 0.7 with M
= 219 kDa, F
g = 0.44 with M
= 222 kDa) gelled using calcium (upper) and strontium (lower) alginate particles. All data points are shown as the mean with standard error of at least three independent runs and curves were fitted to the data by eq. 1. Storage (G’) and loss (G”) moduli, as well as phase angle (tan (G”/G’)) as a function of time after mixing are shown for gels made of sodium alginate containing ~45% and 70% guluronic acid mixed with calcium alginate. The total alginate salt concentration was 2.0% (w/w) i.e. 1.0% from each of the two components (upper panel), 2.1%, consisting of 1.0% from sodium alginate and 1.1% from strontium alginate (lower panel). Calculated maximum elasticity (A) and half time (t
1/2) for the gels are shown.