Degree Type


Date of Award


Degree Name

Master of Science


Agricultural and Biosystems Engineering


Agricultural and Biosystems Engineering

First Advisor

Chenxu Yu


Food safety has always been an essential topic in our lives; about 30 foodborne disease outbreaks occurred each year for the last decade. People paid more attention and were more cautious about the food safety issue than ever before. Food manufacturers also aim to provide more healthy and safer food products to customers. In the past, low moisture foods (LMFs) have not drawn too much attention and concern as being with a high risk of contamination with foodborne pathogens. More and more cases of outbreaks related to LMFs changed that perception, and now LMFs are no longer assumed safe automatically.Conventional detection methods such as ELISA (Enzyme-linked immunosorbent assay) and PCR (Polymerase chain reaction) used to test the foodborne disease pathogens nowadays often require a flow-based system that relies on multiple washing steps to collect the pathogens from foods for analysis. These systems cannot provide a rapid and convenient test for LMFs, which, by definition, do not flow. In this thesis, A Dual Immunological Raman-Enabled Crosschecking Test (DIRECT) scheme was developed to provide direct and rapid detection of foodborne disease pathogens in LMFs. Surface-Enhanced Raman Scattering (SERS) technique was applied in this detection method to achieve a low limit of detection threshold (at 10^2 CFU/g in model LMF systems). We demonstrated the feasibility of this approach with two MRAs (molecular recognition agents). With the help of tape-based sampling and Raman mapping, the method has the potential to become a powerful tool for the detection of pathogens in LMFs to address this critical need for the food industry.


Copyright Owner

Cheng Pan



File Format


File Size

72 pages