Gelatin/cassava starch films: effects of polymer ratio, citric acid crosslinking, and turmeric extract incorporation
Year: 2026
Type: article
Abstract: In this study, we have used gelatin (G) and starch (S) to develop biobased films with different gelatin and cassava starch ratios (G:S 100:0, 90:10, 70:30, 50:50, 30:70, 10:90, or 0:100) with or without turmeric extract (T) at 1% or 10% (G:S 1 T, G:S 10 T, and G:S respectively). We have also prepared G:S films crosslinked with citric acid (C) with or without T at 1% or 10% (G:S C, G:S C1T, and G:S C10 T, respectively) in an attempt to obtain films with active properties and good mechanical and functional properties. The G:S 50:50 film presented phase separation and performed poorly from the mechanical and functional standpoints, so G:S 50:50 was a critical ratio. Increasing G content provided improved mechanical performance and tensile strength as high as 18.19 MPa, whereas increasing S content reduced water solubility (from ~95% to ~48%) and water vapor permeability (from 8 × 10 −9 to 3 × 10 −9 g·m·min −1 ·m −2 ·Pa −1 ). Adding 10% T enhanced the antioxidant activity up to ~87–88% and imparted antimicrobial activity against Streptococcus agalactiae and Streptococcus uberis . Despite evidence of some crosslinking, adding C apparently elicited a plasticizing effect, which resulted in more elongable films, mainly in the case of G:S C10 T films. Among the tested formulations, G:S 10:90 C10 T and G:S 30:70 C10 T showed the best overall balance of water resistance and barrier properties, while G:S 90:10 1 T exhibited the most balanced mechanical performance. These results demonstrate that tuning the polymer ratio and additive combination is an effective strategy when designing active biobased films.
Institution: Universidade de São Paulo
Language: English
Subfield: Biomaterials
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,390
Awards: G3191498954, G3690646728, G4135613835
OpenAlex ID: W7159830908