LAUSR

Abstract Visual pH-sensing cellulose acetate (CA)-based films was incorporated with different concentrations of red cabbage extract (RCE). The films were characterized by color, barrier and thermal properties, microscopic and topographic characteristics, mechanical performance, detection capacity of volatile ammonia, and time-dependent color stability and lighting. The RCE incorporation into CA-based films promoted a color-changing capacity with an increased light barrier and exhibited a plasticizer effect on the mechanical properties of the films. Moreover, the surface patterns of films were heterogeneous and irregular due to the presence of RCE aggregates, which increased as the extract concentration enhanced. The intelligent films showed excellent performance to detect volatile ammonia after 15 min of contact time, despite lower thermal stability and oxygen barrier. The detection of volatile ammonia was fitted well to a statistical model (p