The researchers are in the middle of the in-person and online survey that asks growers about their production scales, harvesting methods, and cleaning and sanitation practices for harvest containers and mechanical harvesters. They’ve enlisted local extension specialists and county agents in different states of the U.S. to collect survey responses. The researchers set a goal of 100 completed responses for a representative sample size. So far, 68 growers and packers from 12 states have completed the survey, and Chen said they are working to reach the target this winter.
Berry growers use different methods and frequencies to clean and sanitize harvest containers and machine harvesters. Based on the survey results, the researchers will collaborate with the advisory board — comprising selected berry growers, packers, extension specialists, and other industry experts — to identify promising cleaning and sanitation practices for further evaluation.
In a field study, the researchers plan to swab the surface of harvest containers and machine harvesters before and after they are cleaned and/or sanitized. They will screen for indicator microorganisms in the samples. By comparing the microbial load in the before- and after-sanitation samples, they can validate the efficacy of the selected hygiene practices.
Drawing from survey results and advisory board input, Chen said they also plan to mimic the key cleaning and sanitation practices in the laboratory and determine the efficacy of these practices in removing microbial buildup and biofilm on materials used to manufacture harvest containers and mechanical harvesters.