News about nanotechnology is reported almost every day. Nanotechnology in agriculture, not so much. Nanotechnology made from agricultural products, we hear about that even less. So this story concerning research done at Purdue University (Indiana, USA), which uses nanoparticles manufactured from corn to extend the shelf life of certain oils demonstrates the radiation of nanotech into so many fields (pardon the pun).
Yuan Yao, an assistant professor of food science, has successfully modified the phytoglycogen nanoparticle, a starchlike substance that makes up nearly 30 percent of the dry mass of some sweet corn. The modification allows the nanoparticle to attach to oils and emulsify them while also acting as a barrier to oxidation, which causes food to become rancid. His findings were published in the early online version of the Journal of Agricultural and Food Chemistry.
Yao was able to modify the surface of phytoglycogen nanoparticle to make it behave like an emulsifier, creating phytoglycogen octenyl succinate, or PG-OS. PG-OS is thicker and denser than commonly used emulsifiers, creating a better defense from oxygen, free radical and metal ions, which cause lipid oxidation.
Yao’s findings also showed that ?-polylysine, a food-grade polypeptide, can be added to the oil droplets to aid in the protection from oxidation. Polylysine is much smaller than the PG-OS nanoparticles, allowing it to fill in the gaps between PG-OS nanoparticles.
According to Yao’s study, PG-OS nanoparticles with ?-polylysine significantly increased the amount of time it took for oxidation to ruin the oil droplets, in some cases doubling the shelf life of the model product. Shelf life was tested by warming the emulsifiers and checking for chemical reactions that signal oxidation has occurred.
[Source: Purdue University]
A patent is already pending for this use of corn-derived nanoparticles, which is an indicator of how viable the approach may be in terms of commercial application. It seems that the ability of nanoscale materials to make novel and useful surfaces (coatings) is one of the most lucrative and therefore powerful drivers in nanotechnology research.