NOVEMBER-DECEMBER 2021 FPT food protection trends Vol. 41, No. 6 | ISSN: 1541-9576 | Periodicals 2900 100th Street, Suite 309, Des Moines, Iowa 50322-3855, USA Root Cause Analysis Can be Used to Identify and Reduce a Highly Diverse Listeria Population in an Apple Packinghouse: A Case Study SCIENCE AND NEWS from the International Association for Food Protection