Table 5.
Thermal degradation temperature (Td, °C) and weight loss (Δw, %) of films incorporated with GTE at different concentrations of green tea extract (GTE) at pH 3 and pH 11. Δ1, Δ2, Δ3, and Δ4 represent first, second, third, and fourth stages, respectively, of weight loss of films during the heating scan.
| Samples | (w/w of Protein) | Δ1 | Δ2 | Δ3 | Δ4 | Residue (%) | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Td1 | Δw1 | Td2 | Δw2 | Td3 | Δw3 | Td4 | Δw4 | |||
| pH 3 | Control | 127.7 | 4.9 | 187.6 | 20.7 | 312.7 | 18.5 | 455.2 | 18.3 | 35.6 |
| 2% | 144.7 | 4.5 | 209.7 | 25.2 | 319.1 | 16.6 | 445.1 | 17.1 | 36.6 | |
| 4% | 147.2 | 4.9 | 205.2 | 18.3 | 304.7 | 13.9 | 427.2 | 19.4 | 43.5 | |
| 6% | 148.5 | 3.8 | 221.1 | 21.5 | 309.5 | 10.1 | 423.6 | 20.1 | 44.5 | |
| pH 11 | Control | 160.4 | 11.3 | 235.3 | 24.5 | 397.6 | 30.2 | 487.6 | 4.1 | 29.9 |
| 2% | 177.6 | 11.9 | 251.9 | 25.3 | 392.6 | 27.4 | 495.1 | 5.6 | 29.8 | |
| 4% | 167.1 | 10.0 | 263.6 | 25.5 | 391.1 | 23.8 | 467.6 | 6.8 | 33.9 | |
| 6% | 176.3 | 11.7 | 275.4 | 26.5 | 337.5 | 13.4 | 440.6 | 14.3 | 34.1 | |