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Colourimetric TTIs are based on chemical, physical and enzymatic processes\cite{Arias_Mendez_2014} and have wide application in smart packaging, with applications to chilled or frozen foods. In smart packaging, this kind of sensors change their colour due to a change in a critical state, for example, the growth of micro-organisms fires changes in pH of the food, which in turn induces a colour change in a indicator dye, allowing the packaging to provide visual information about the product.\par  These films are basically prepared by the casting technique, which has low cost and high efficency for film preparation. Briefly, composite hydrocolloid films are prepared by suspending an amount of biopolymer in distilled or deionized water. The suspension is poured in acrylic or glass plates and dried until constant weight in order to obtain the films. Among the most diverse biopolymers that have been applied to smart and active packaging, biopolymers such as starches, gums, pectin, gelatin and chitosan are the polymers that have greater stability, due to their ability to form networks structured and thermally stable copolymers. Moreover, these polymers can form stable hydrocolloid suspensions and the casting of hydrocolloid suspension films has been successfully applied in the development of smart films prepared with polyaniline\cite{GARCIA_2004}, Cassava Starch/Glycerol\cite{Golasz_2013}\cite{Kuswandi_2012}, Chitosan\cite{Yoshida_2014} ,Chitosan/PVA\cite{Silva_Pereira_2015}\cite{Pereira_2015} and Chitosan/Starch films\cite{V_sconez_2009}. Hence, casting is a versatile, unexpensive, rapid and simple technique of film peparation that is well established in the literature. Although other techniques such as nancomposites\cite{Qureshi2012}, Layer-by-Layer\cite{Brasil_2012} and polymeric matrix \cite{Marek_2013} are also used to develop smart polymer films, the simplicity of casting technique, which does not requires complicated laboratorial instruments makes the casting technique the choice for the development of new and improved smart polymer films. Another advantage of the casting technique is that it allows the easy incorporation of micromolecules into the polymeric film by justing adding molecule such as natural pigments that act as sensors, into the film-forming solution. \par  There are several pigments, both natural\cite{Chigurupati_2002}\cite{Zhang_2014}\cite{Silva_Pereira_2015}\cite{Pereira_2015} and artificial\cite{Kim_2012}\cite{Salinas_2012}, that are used for the purpose of sensing dyes and there are many research focusing the application of such pigments as sensors in alternative thin films on smart packaging. packaging~\cite{VeigaSantosP;DitchfieldC;Tadini2011}.