Properties Evaluation of pH-sensitive films based on starch/tragacanth and common mallow (Malva sylvestris) anthocyanins

The effect of addition of Malva sylvestris extract on the structural (FT-IR, XRD, SEM), physical (moisture, water solubility, WVP), mechanical (TS and elongation at break) properties, color, sensitivity to pH and ammonia of starch/tragacanth films were investigated. Results showed that the moisture content and water solubility were significantly lower in the films containing anthocyanins than control starch/tragacanth film. WVP of films were decreased with increasing the anthocyanins concentration. The TS of films were decreased with addition of anthocyanins and lowest TS were observed in the films containing 2% anthocyanins. The extracted anthocyanins were sensitive to the pH changes and lower 5 s the color change was observed. The color of films were pink, purple and green at acidic, neutral and alkaline, respectively. Furthermore, the films containing 0.5 and 1% anthocyanin extract were sensitive to the 0.8 and 1.4 M ammonia and after 20 min the color change were observed. The effect of addition of Malva sylvestris extract on the structural (FT-IR, XRD, SEM), physical (moisture, water solubility, WVP), mechanical (TS and elongation at break) properties, color, sensitivity to pH and ammonia of starch/tragacanth films were investigated. Results showed that the moisture content and water solubility were significantly lower in the films containing anthocyanins than control starch/tragacanth film. WVP of films were decreased with increasing the anthocyanins concentration. The TS of films were decreased with addition of anthocyanins and lowest TS were observed in the films containing 2% anthocyanins. The extracted The effect of addition of Malva sylvestris extract on the structural (FT-IR, XRD, SEM), physical (moisture, water solubility, WVP), mechanical (TS and elongation at break) properties, color, sensitivity to pH and ammonia of starch/tragacanth films were investigated. Results showed that the moisture content and water solubility were significantly lower in the films containing anthocyanins than control starch/tragacanth film. WVP of films were decreased with increasing the anthocyanins concentration. The TS of films were decreased with addition of anthocyanins and lowest TS were observed in the films containing 2% anthocyanins. The extracted anthocyanins were sensitive to the pH changes and lower 5 s the color change was observed. The color of films were pink, purple and green at acidic, neutral and alkaline, respectively. Furthermore, the films containing 0.5 and 1% anthocyanin extract were sensitive to the 0.8 and 1.4 M ammonia and after 20 min the color change were observed. The effect of addition of Malva sylvestris extract on the structural (FT-IR, XRD, SEM), physical (moisture, water solubility, WVP), mechanical (TS and elongation at break) properties, color, sensitivity to pH and ammonia of starch/tragacanth films were investigated. Results showed that the moisture content and water solubility were significantly lower in the films containing anthocyanins than control starch/tragacanth film. WVP of films were decreased with increasing the anthocyanins concentration. The TS of films were decreased with addition of anthocyanins and lowest TS were observed in the films containing 2% anthocyanins. The extracted The effect of addition of Malva sylvestris extract on the structural (FT-IR, XRD, SEM), physical (moisture, water solubility, WVP), mechanical (TS and elongation at break) properties, color, sensitivity to pH and ammonia of starch/tragacanth films were investigated. Results showed that the moisture content and water solubility were significantly lower in the films containing anthocyanins than control starch/tragacanth film. WVP of films were decreased with increasing the anthocyanins concentration. The TS of films were decreased with addition of anthocyanins and lowest TS were observed in the films containing 2% anthocyanins. The extracted anthocyanins were sensitive to the pH changes and lower 5 s the color change was observed. The color of films were pink, purple and green at acidic, neutral and alkaline, respectively. Furthermore, the films containing 0.5 and 1% anthocyanin extract were sensitive to the 0.8 and 1.4 M ammonia and after 20 min the color change were observed. The effect of addition of Malva sylvestris extract on the structural (FT-IR, XRD, SEM), physical (moisture, water solubility, WVP), mechanical (TS and elongation at break) properties, color, sensitivity to pH and ammonia of starch/tragacanth films were investigated. Results showed that the moisture content and water solubility were significantly lower in the films containing anthocyanins than control starch/tragacanth film. WVP of films were decreased with increasing the anthocyanins concentration. The TS of films were decreased with addition of anthocyanins and lowest TS were observed in the films containing 2% anthocyanins. The extracted The effect of addition of Malva sylvestris extract on the structural (FT-IR, XRD, SEM), physical (moisture, water solubility, WVP), mechanical (TS and elongation at break) properties, color, sensitivity to pH and ammonia of starch/tragacanth films were investigated. Results showed that the moisture content and water solubility were significantly lower in the films containing anthocyanins than control starch/tragacanth film. WVP of films were decreased with increasing the anthocyanins concentration. The TS of films were decreased with addition of anthocyanins and lowest TS were observed in the films containing 2% anthocyanins. The extracted anthocyanins were sensitive to the pH changes and lower 5 s the color change was observed. The color of films were pink, purple and green at acidic, neutral and alkaline, respectively. Furthermore, the films containing 0.5 and 1% anthocyanin extract were sensitive to the 0.8 and 1.4 M ammonia and after 20 min the color change were observed. The effect of addition of Malva sylvestris extract on the structural (FT-IR, XRD, SEM), physical (moisture, water solubility, WVP), mechanical (TS and elongation at break) properties, color, sensitivity to pH and ammonia of starch/tragacanth films were investigated. Results showed that the moisture content and water solubility were significantly lower in the films containing anthocyanins than control starch/tragacanth film. WVP of films were decreased with increasing the anthocyanins concentration. The TS of films were decreased with addition of anthocyanins and lowest TS were observed in the films containing 2% anthocyanins. The extracted