Due to the interest in extending the shelf life of food to reduce waste. In addition to the growing interest in developing environmentally friendly packaging, a review of the polymers of natural origin used in food packaging with applications in intelligent and active packaging was carried out. Given the extension of the topic, the search focused on the two most reported materials: alginate and chitosan. Both have been used in the development of smart and active packaging due to their specific properties. Alginate is obtained from various marine products, which makes it a renewable resource. Its application in food packaging ranges from films modified with bioactive compounds and the inclusion of nanoparticles, to blending with other polymers. These blends and synthesis can improve its mechanical properties, while remaining a degradable material. Chitosan is obtained mainly from the exoskeleton of marine products. This material is obtained from agro-industrial waste, which gives it added value. Chitosan has been used to develop smart and active packaging. Its characteristics as a film are improved by including particles, combining it with other materials and adding indicators that give it a real-time sensor function. Finally, a comparison was made between the two polymers of natural origin, in order to facilitate the orientation of future research. Given the results of the review, the recommendation would be to evaluate the advantages and disadvantages of each polymer to choose the indicated one according to the need for food preservation. It is concluded that despite all the work reported to achieve better food packaging and waste reduction, there is a clear need to bring each research to a practical application. It would be recommended to implement production technologies so that these materials can be used, since their nature is suitable for use in cleaner industrial production chains.
Keywords: Biopolymers, Food packaging, Food safety, Smart polymers.