March 18, 2025 - Rory Wang, Ph.D. Candidate (Worobo Lab), Cornell University

Rory Wang is a fourth-year PhD candidate in Dr. Randy Worobo's research group. He attended Iowa State University for his B.S. in food science and attended Washington State University for his M.S. in food microbiology. His current research focuses on advancing microbial aspects of high pressure processing applications in juices. He also enjoys working on extension and outreach projects, and he serves as the current chair for the Community Outreach Committee in the department.

High-pressure processing (HPP) is a non-thermal food processing technology that has been quickly adapted by the juice industry in the past decade. HPP can preserve nutrients and flavor compounds otherwise lost during conventional thermal processing of juice products. However, there are two caveats that require more research input to better advance this technology: 1) the efficacy of HPP against protozoan parasites remains unclear and 2) HPP is not effective against bacterial spores.

Cryptosporidium parvum is a pertinent parasitic pathogen in apple juice and Juice HACCP requires that juice processing must be able to achieve a 5-log reduction against it. Gold standard validation of parasite inactivation in juices relies on animal models, which can be costly and difficult to perform. My research explores validity and practicality of animal-free models, particularly focusing on the human cell line-based infectivity models and the mRNA-based viability model.

Alicyclobacillus acidoterrestris is a spore-forming bacterium that causes spoilage in shelf-stable juices and juice products. HPP is not effective against spores of A. acidoterrestris and other spore-formers. Therefore, all pressure-treated products must be refrigerated to extend their shelf life, adding to the existing high costs of HPP products. My research explores the possibility of utilizing a natural antimicrobial glycolipid extracted from edible fungi to achieve shelf stability of HPP-treated apple juice. We are also attempting to elucidate the antimicrobial mechanism of this natural glycolipid via RNA sequencing.