the study of freshness and temperature – time indicators in food active packagingthe study of freshness and temperature – time indicators in food active packaging

today the usage of some compounds as indicator, can be checked changes of the food quality without opening the package. the most important indicators are indicates that show the level of product quality and freshness. freshness and temperature - time reagents reflect on extension of the product quality. indicators show the quality of the product, by physical and chemical changes which will be led to a visual change this article tries to review new freshness and temperature - time indicators according to recent research in this field.