Gum arabic improves the mechanical properties of wild almond protein film.

In this study, different films were manufactured using protein isolate extracted from wild almond (WAPI) in combination with different ratios of gum arabic (GA). Based on the mechanical properties of films including tensile strength (TS), elongation (E), and water vapor permeability (WVP), WAPI-GA with the ratio of 9:1 was selected. Accordingly, the mixture was incubated (T = 60 °C, RH = 79%) for 3, 6 and 9 days in order to conjugate WAPI with GA. Analysis of the films showed that after 6 day incubation, TS and E value were increased, while WVP was significantly reduced. Longer reaction presented adverse effects. SEM analysis of the films revealed the enhancement of compactness, and reducing of porosities after glycation. Differential scanning calorimetry showed that WAPI-GA incubated for 6 days have higher onset (Tonset) and endset (Tendpoint) temperatures than the control sample. The shifts in FTIR spectra after conjugation the confirmed occurrence of interaction between WAPIs and GA.