Summary of Awards to Date

Non invasive imaging approaches to evaluate potential infusion of pathogens during vacuum cooling of lettuce leaves and real time dynamics of microbes on leaf tissues as a function of moisture content.


Jan. 1, 2011 - Jan. 31, 2012

Award Number


Funding Agency

Center for Produce Safety

Amount Awarded



Nitin Nitin, Ph.D.
University of California, Davis


The proposed research is aimed at developing non-invasive imaging methods to
characterize interactions of pathogens with leafy green vegetables and evaluate the potential
risk of infiltration/infusion upon vacuum cooling of leafy greens. The proposed study uses
lettuce as a model system to demonstrate the potential of non-invasive imaging methods to
detect changes in structure of pathogens both on surface and in side of leafy green vegetables
as a function of moisture content. With vacuum processing, effect of different varieties of
lettuce, role of process conditions (spray water, vacuum pressure and release rate of vacuum)
and differences in laboratory and field inoculated lettuce on localization will be compared using
non-invasive imaging methods.
Results of this study will provide a comprehensive assessment of potential risks of
infiltration during a vacuum cooling process and practical approaches to address the risk