Desenvolvimento de embalagens alimentícias ativas e inteligentes com extratos de plantas medicinais

Abstract

Plants from the Asteraceae family are known for their antimicrobial and antioxidant properties, which is why they can be used in developing chitosan-based films as a more sustainable alternative. Incorporating natural extracts with bioactive properties into sustainable films is known as active packaging, aiming to extend the shelf life of foods. Furthermore, intelligent packaging has attracted significant attention due to its ability to monitor and communicate information about food conditions by changing the film's color according to pH changes. In this context, this study aimed to develop chitosan films for active and intelligent food packaging by incorporating extracts from plants from the Asteraceae family and grape pomace. Ethanolic extracts of carqueja, macela, and ground grape pomace were produced in an ultrasonic tip sonicator. The guaco ethanol extract was provided by Sustentec. These extracts were subsequently characterized for antioxidant activity, total phenolic compounds, and flavonoids. According to preliminary studies, films were then prepared using the adapted casting technique, incorporating these extracts into the films at concentrations of 10 % and 20 %. They were then characterized according to visual appearance, thickness, moisture content, water solubility, swelling index, water vapor permeability (WVP), light barrier, in vitro release test, and pH sensitivity. The extracts showed high antioxidant activity and phenolic compound content, particularly guaco and macela. The extract-incorporated films were uniform and malleable, with no difference in thickness. However, they showed higher moisture content, water solubility, and WVP content than the control films. In contrast, the swelling index and light barrier properties demonstrated desirable characteristics for the films as potential food packaging. In vitro phenolic compound release tests showed that the film incorporated with guaco and grape pomace presented greater release of the acidic food simulant compared to all films, thus reinforcing the film's functional potential as an active food packaging rather than simply as a physical barrier. In the pH sensitivity test, the films showed a color change similar to the grape pomace extract only at pH 2.2 and 4.0. At the other pHs, the color remained close to the control film's. It is concluded that chitosan-based films incorporated with extracts from plants of the Asteraceae family and grape pomace presented promising alternatives for food packaging. However, further studies are needed to improve the moisture barrier and maximize functional properties.