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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. 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 these molecules, such as natural pigments that act as sensors, into the film-forming solution. \par  There are several pigments 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 sensors sensing dyes  and very there are many  research in focusing  the development application  of these such pigments as  sensors in alternative thin films on packaging from oil. smart packaging.  Among the most diverse natural products that have been studied, biopolymers such as starches, gums, pectin, gelatin and chitosan are the ones that have stability, because they form networks structured copolymers. In addition to biopolymers, various natural pigments are also being investigated with regard to application in sensors in thin films.