Feasibility of Sanitizing Apple Field Bins to Eliminate Postharvest Pathogens

Abstract

New York State produces approximately 26 million bushels of apples each year. Apples harvested in autumn are held in low-oxygen storage for up to 10 months to allow orderly marketing of the crop and to provide consumers with a year-round supply of high-quality fruit. However, several fungal pathogens can cause apples to decay during storage and shipping. In a survey during winter/spring of 2000 and 2001, decayed Empire apples were evident in bagged apple displays in nearly 40% of retail stores surveyed. Fungal spores can be carried from season to season on the large bins that are used to hold fruit during storage. Sanitizing bins after they are emptied might break the disease cycle, thereby reducing both losses in apple storages and the incidence of decays in bagged apples at the retail level. Commercial sanitizers (sodium hypochlorite and quaternary ammonia compounds) were compared for effectiveness using small, uniformly-contaminated pieces of wood and plastic bin materials. None of the sanitizers were effective for killing spores of Penicillium expansum that were grown on wooden blocks soaked in apple juice. Results of this work suggest that steam cleaning may be necessary to remove inoculum from apple bins.