Cassava flour (CF) was used as a raw material to replace wheat flour (WF) at levels of 0% (control), 10%, 20%, 30%, 40%, and 50% to prepare wheat–cassava composite flour (W-CF) and dough. The effects of different CF substituting levels on the functional properties of the W-CF and dough were investigated. The results show that an increase in CF led to a decrease in the moisture, protein, fat, and b* values of W-CF. The crude fiber, ash, starch, L*, a* values, iodine blue value (IBV), and swelling power (SP) of the composite flour increased gradually. It was found that the water absorption, hardness, and chewiness of the W-CF dough increased with an increase in the CF substitution level. A different trend could be observed with the springiness and cohesiveness of the W-CF dough. The resistance to extension, extensibility, and the extended area of the W-CF dough at all substitution levels was significantly lower than that of the WF dough. The elasticity and cohesiveness of the dough tended to increase for CF content from 10% to 30%, followed by a decrease at a higher replacement. Pearson correlation analysis indicated that the substitution levels of CF had a significant influence on the proximate analysis and functional properties of the W-CF and dough. This study will provide important information on choosing CF substitution levels for different products.

Laponite^® (LRD) was modified with ethyl lauroyl arginate (LAE) to form complexes, which were subsequently incorporated into solutions of silk peptide (SP) and chitosan (CS) to prepare SP–CS biopolymer composite films by the casting method. Compared with LRD, the LRD/LAE complex demonstrated superior dispersibility within the SP–CS film, thereby improving the compatibility between SP and CS. The mechanical, thermal and antimicrobial properties of the SP–CS film increased while the water vapor permeability (WVP) decreased with the incorporation of the LRD/LAE complex. Remarkably, the SP–CS film containing 2% LRD and 1% LAE complex (SP–CS–C) exhibited the lowest WVP (0.35 g·mm·m⁻²·h⁻¹·kPa⁻¹) resulted in the highest tensile strength (27.99 MPa) and elongation at break (81.62%). When an edible bananas coating was applied, the weight loss of the SP–CS–C film decreased to 13.92%, and the hardness (176.94 g), titratable acidity (0.15%), and total soluble solids (19.20%) improved. The microbial counts decreased to 3.80 log CFU/g for the colonies and 3.30 log CFU/g for the molds on day 7, whereas they decreased to 5.78 and 4.65 log CFU/g, respectively, in the control group. These results show that the SP–CS–C film extends the banana shelf life during storage at 25 °C and approximately 50% RH for 7 days.