ARS | Publication request: A REVIEW OF SANITIZING METHODS USED IN FLORIDA ON PACKINGLINES

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2006
Publication Date: N/A

Technical Abstract: Sanitation literally means "to promote health" and is usually associated with applications to reduce disease-causing microorganisms on foods or food contact surfaces. In packinghouses, this includes reducing the number of fungal spores on fruit contact surfaces (e.g. brushes and belts) as well as on fruit surfaces that can cause postharvest decay. To be most effective, fruit and packinghouse sanitation should begin with Good Agricultural Practices in the grove. The goal is to harvest fruit with minimum peel damage (e.g. wounds, scab) and without infection from latent disease. This is partially accomplished with prudent tree pruning as well as the application of a preharvest spray. At the packinghouse, sanitation practices continue with cleaning and sanitizing the line and the fruit. Split or decayed fruit should be culled from the line, as removing these diseased fruits from any proximity to the packingline will avoid re-contamination. There are a variety of ways to sanitize the fruit and/or fruit contact surfaces. The effectiveness of sanitizers depends on such factors as pH, concentration, contact time, and the general condition and type of the commodity. Commonly used sanitizers in Florida include chlorine based dips or drenches, hot water under pressure and peroxyacetic acid. Growing in use, ozone (used often in re-circulating water systems) reduces microorganisms on produce surfaces and has been found to be successful in reducing decay caused by some fungi. Ozone will not prevent growth of fungi once they are in wounds and peel abrasions. Chlorine dioxide is an anti-fungal sanitizer that can be used over a wide pH range, but may be expensive to use and, if the packinghouse is not adequately ventilated, and can cause respiratory problems in packinghouse workers. Sanitizers should be a part of an integrated program of processes and possibly other chemicals to maintain fruit quality. It is important to remember that sanitizers have several limitations, one being that they have no residual effect. To make sanitizers more effective, increasing exposure time rather than concentration may reduce numbers of viable spores on fruit surfaces without causing problems for workers or equipment. Regular cleaning of brushes (especially in non-recovery systems) is necessary as spores can accumulate on them; sanitizers would be well used here. Non-recovery systems are found to have a higher incidence of microorganisms throughout the packingline and these should be carefully maintained and sanitized so clean fruit is not re-inoculated at the end of the packinghouse process.