Antifungals like natamycin are added to prolong the shelf life of foods. Since microorganisms tend to develop resistance to antifungals when they remain in contact with them, the effect of the antifungals slowly diminishes. This means that it is necessary to control their release rate to have an additional advantage over the microorganisms.
There are some sensitive systems that in some cases respond to more than one stimulus: for example, temperature and pH. This type of stimulus is primarily known as thermo-effective material and is made up of a material that consists of two types of groups: hydrophilic and hydrophobic.
The hydrophilic group is able to create a cover around the hydrophobic group, with natamycin acting as a release material thanks to its antifungal properties. This is, in turn, able to raise or lower the temperature depending on the group.
This leads to the conclusion that both parameters – temperature and pH – are fundamental in food packaging and storage processes.