Alginate gels were formed by varying the concentrations of sodium alginate (0-3%), calcium chloride (0-2%), pH (2-5), and temperature (0-40 degrees C) employing a second order central composite rotatable design. These gels were characterised with particular reference to texture parameters (linear limit, firmness and rupture characteristics like rupture force/strain/energy). Multiple correlation coefficients between 0.840 and 0.925 (significant at p <= 0.01) indicate the suitability of the second order polynomial in terms of these four variables. The concentration of sodium alginate mostly provides a negative effect on the rupture characteristics (significant at p <= 0.05) while calcium chloride has a positive (p <= 0.01) effect on the linear limit of gels. The hierarchical cluster analysis involving the response functions shows a strong similarity between these three rupture characteristics. The principle component analysis (PCA) can segregate the conditions like 'no gel formation' and 'strong gel' zones.(c) 2008 Elsevier Ltd. All rights reserved