Nanoparticle Protects Oil in Foods from Oxidation, Spoilage

WEST LAFAYETTE, Ind.—Using a nanoparticle from corn, a Purdue University scientist has found a way to lengthen the shelf life of many food products and sustain their health benefits.

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.

Oxidation destabilizes oil droplets in emulsified food, degrading and changing the chemical structure of the oil and causing it to go bad. This oxidation happens in a wide range of products, shortening their shelf lives. Yao said that the nanoparticle can be widely used in the food industry, cosmetics and nutritional supplements, any system in which the oxidation of lipids is a concern.

Yao was able to modify the surface of phytoglycogen nanoparticle to make it behave like an emulsifier, creating phytoglycogen octenyl succinate, or PG-OS. Yao's findings also showed that e-polylysine, a food-grade polypeptide, can be added to the oil droplets to aid in the protection from oxidation, and that PG-OS nanoparticles with e-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.

Read the full story at Purdue.edu.