Mechanical properties of the RBP/gelatin blend film
To prepare the RBP blend films having better physical
property than the RBP/RA blend films, various
concentrations of gelatin were incorporated into the filmforming
solution to improve the physical properties of the
RBP film (Table 4). The thickness of the RBP/gelatin
blend film increased with increasing amounts of gelatin,
although the same amount of film-forming solution was
used. The TS of the RBP/gelatin blend film increased
when the gelatin content increased. The RBP film
containing 2.0% gelatin had a TS of 11.10 MPa, while the
film containing 4.0% gelatin had a TS of 23.90 MPa. Cao
et al. (24) reported that the TS increased as the gelatin
content increased. Li et al. (25) and Xiao et al. (26) also
reported an increase in the TS when gelatin was blended
with konjac glucomannan film, and they suggested that the
increase in TS could be due to the increase in hydrogen
bonding between gelatin and the film base materials. The
E of the film reflects the film’s stretch capability. Our
results showed that the E of the 4% RBP/4% gelatin blend
film had the greatest E (141.02%), while the 4% RBP/3%
gelatin blend film had the lowest (93.61%). In addition, the
Table 2. Mechanical properties of the rice bran protein (RBP)/1% red algae (RA) blend film containing various amounts of RBP
RBP content
(%)
Thickness
(μm)
Tensile strength
(MPa)
Elongation
(%)
Water vapor permeability
(ng·m/m2·s·Pa)
3.0 68.40±1.14c1) 1.41±0.11b 51.35±14.00a 2.69±0.21a
4.0 74.00±3.39b 1.44±0.17b 51.04±12.33a 2.69±0.24a
5.0 85.20±3.11a 3.63±0.20a 32.04±4.78b 1.77±0.01b
1)Each value was the mean±SD (n=5); Any means in the same column followed by different letters are significantly different at p