A food scientist and analytical chemist, Lili He, at the University of Massachusetts Amherst has received a three-year, $473,628 grant from the USDA National Institute for Food and Agriculture to study mechanisms of how chemical pesticides, applied both systemically and to the surface, penetrate fresh produce and move into plant tissues, and how this may affect food safety for consumers.
Lili He has developed an innovative surface enhanced Raman spectroscopy (SERS) method for studying pesticides on and in fresh intact produce. Her research will focus on apples, grapes and leaf spinach as representatives of three different skin structures in fruits and vegetables: apples have a thick skin that can be peeled, grapes have an ultra-thin skin that is usually not peeled and spinach has no skin.
“One thing we want to know is whether pesticides applied to these different skin surfaces penetrate the skin and how far, and if they can be easily washed off”, He said. “From some preliminary experiments, we know that non-systemic pesticides applied to the surface of fruits and vegetables can penetrate the skin by several microns which would be very hard to wash it away, but it has not been studied thoroughly”, she adds.