Edible sensor and barcode: for food packaging
Bas Cramwinckel · Research Repository (Delft University of Technology) · 2019
To reduce food spillage and the counterfeiting of products an indicator is needed, which can indicate if a product is still suited for consumption. In this study a new indicator, made from a caseinate glycerol film, has been tested. The film breaks after exposure to humid air after a certain time. The indicator can indicate if a food product is still safe to eat or not and could indicate if a product packaging has been opened when transported. Three different compositions of the caseinate glycerol film were tested for their capacity to absorb water and for their strength. The highest water absorption in percentage of water per polymer was at the higher humidity level. The different compositions showed an increase in absorption depending on its thickness and glycerol content. The film which best absorbed the water was the thinnest film. This is explained by its relatively large surface area versus volume in comparison to the other two tested films. The difference in water absorption was ten times higher at 85% humidity as compared to the water absorption at 60%. From the strength test it appeared that the film with the lowest glycerol content was the film which broke the easiest after being exposed to humidity. The other samples did not break due to the limits of the equipment used. The sample who did break with lowest glycerol content for its volume shows the most potential to be used as an indicator because of the relatively low strain required to break the film.