ties should be analyzed simultaneously (Altenhofen da Silva et al.,
2009).
Table 1 shows tensile strength and elongation at break of sodium
alginate/pectin films. Values of tensile strength ranged significantly
(p < 0.001) from 22.5 to 42.3 MPa with the lowest value for
pectin film and the highest for 1:1 alginate to pectin film (Film C).
Elongation at break ranged from 5.9% to 14.9% with the highest values
for mixed films. Values of pure pectin film are different compared
to those obtained by Kang et al. (2005) who demonstrated
tensile strength of 193 MPa and elongation at break of 2.6%. Similarly,
values for pure alginate film were also different from those
presented by Rhim (2004) and Olivas and Barbosa-Canovas
(2008). Combination of sodium alginate and pectin gave films with
higher tensile strength and elongation at break due to compatibility
and chemical synergetic interaction between components (Table
1). The mechanical profiles of pectin and sodium alginate
composite films could indicate the structure development. This
phenomenon was presented in literature. Pascalau et al. (in press)
showed significant increase in elongation at break for composite
films from alginate and k-carrageenan. Similar results were presented
by Wang et al. (2010) for gelatin–sodium alginate composite
films and by Xu et al. (2005) for chitosan–starch composite
films.