Development of novel, UV-activated, intelligent inks for food packaging

大多数食品都是在改良的气氛下包装的，以排除氧气，而氧气是导致大多数包装食品变质的原因。这种气调包装的问题是，没有廉价的方法来识别包装密封是否完好无损；因此，MAP中的质量控制是100%的。该项目旨在利用离子配对技术和大带隙半导体光敏剂，开发一系列用于MAP的可溶于溶剂、UV-B激活的氧敏油墨。还原气体乙烯是一种生长激素，大多数新鲜农产品，特别是西番莲果、桃子和梨在成熟过程中会释放出乙烯；含量约为1ppm的乙烯可以启动其他新鲜农产品的成熟过程。包装中累积的乙烯水平提供了包装新鲜农产品所经历的成熟程度的衡量标准。乙烯和智能墨水的商业指标很少，如果有的话。因此，利用与氧气指示剂相同的基本原理，该项目还将为新鲜农产品包装行业开发一系列溶剂型、UV-B激活的乙烯敏感油墨。这些指标可能会对食品包装中存在的其他还原气体做出反应，如醛和酮，这些气体也与成熟过程有关。但是，将特别注意乙烯敏感指标的开发。该项目将为指定的博士生提供一个极好的培训，他将使用广泛的分析技术，与一家主要的油墨制造商密切合作，并将该技术推广到食品包装行业。

Most food is packaged under a modified atmosphere in order to exclude oxygen, which is responsible for most packaged food spoilage. The problem with such modified atmosphere packaging, MAP, is that there is no inexpensive way to identify if the package seal is intact; as a consequence QC in MAP is << 100%. This project aims to develop a range of solvent-soluble, UV-B activated, oxygen sensitive inks for MAP, using ion-pairing techniques and large-bandgap semiconductor photosensitisers. The reducing gas, ethylene, is a growth hormone, emitted by most fresh produce, especially passion fruit, peaches and pears, as part of the ripening process; levels of ca. 1 ppm can initiate the ripening process in other fresh produce. The level of accumulated ethylene in a package provides a measure of the degree of ripening undergone by the packaged fresh produce. There are few, if any commercial indicators for ethylene and no intelligent inks. As a result, and using the same basic principles as that for the oxygen indicators, this project will also develop a range of solvent-soluble, UV-B activated, ethylene sensitive inks for the fresh produce packaging industry. These indicators may respond to other reducing gases present in the food package, such as aldehydes and ketones, which are also associated with the ripening process. However, particular attention will be given to the development of ethylene sensitive indicators. The project will provide an excellent training for the named PhD student, who will use a wide range of analytical techniques, work closely with a major ink manufacturer and promote the technology to the food packaging industry.