Evaluation and optimization of postharvest intervention strategies for the reduction of bacterial contamination on tomatoes

Evaluation and optimization of postharvest intervention strategies for the reduction of bacterial contamination on tomatoes

Oct. 1, 2009 - Oct. 31, 2011

2009-51

$293,240.00

Keith Schneider, Ph.D.
University of Florida

Renee Goodrich-Schneider, Ph.D., Yaguang Luo, Ph.D., Steven A. Sargent, Ph.D.

Final Report

Publication

Publication

Publication

Publication

Tomatoes are a nutritious food and an important crop for the state of Florida and the US economy. Yet, foodborne illness outbreaks associated with tomatoes have negatively impacted public health, consumer confidence in tomatoes, and the industry’s economic well-being. The Florida tomato industry has taken an active role in establishing tomato-handling standards to prevent pathogen contamination and infiltration. However, due to lack of scientific data
applicable to commercial handling conditions, some of the standards rely upon recommendations previously developed for tomato quality maintenance. Therefore, scientific studies to evaluate pathogen contamination and infiltration under realistic commercial handling conditions are critical for developing handling practices to effectively reduce pathogen contamination. Proposed research will focus on evaluating current tomato post-harvest handling practices on
Salmonella contamination and infiltration, and providing answers to the queries raised by the industry. Goals include defining operational limits for dump tank water management, identifying cost-effective dump tank water quality monitoring parameters, and developing/optimizing an overhead spray sanitation system to minimize tomato surface contamination while reducing water and chemical use. Project outcome will provide data for developing science-based guidelines to reduce food safety risks, and avoiding setting up costly regulations that may not necessarily advance food safety.

Technical Abstract

Tomatoes are a nutritious and valuable food crop that is important to Florida's economy as well as that of the US. About 71% of fresh tomatoes are grown in Florida and California, of which Florida's share amounted to $630 million (AMRC, 2009). Unfortunately, the tomato industry has been troubled with several foodborne illness outbreaks associated with consumption of tomatoes contaminated with Salmonella spp. in recent years. The overall goal of this project is to provide tomato growers and packers specific information that will allow the improved food safety of fresh tomatoes. Information gained will allow “functional limits” to be set, which “an operator can use to ensure that effective sanitizer concentrations are present in the dump tank,” and provide an answer as to when “the addition of additional chlorine is ill‐advised or ineffective and the water needs to be partially or fully changed?” Other impacts of this work will include reduced water use by utilizing fine mist sprayers as opposed to large-volume flume tanks that require daily filling, draining and cleaning. Additionally, since the water used in the overhead spray system is not recirculated, less chemicals could be used, reducing the overall cost of operation and lowering the environmental impact of a packing operation. The overall outcome of this work will be to answer fundamental questions. Information gained will provide answers to set “functional limits an operator can use to ensure that effective sanitizer concentrations are present in the dump tank,” and answer the question as to when “the addition of additional chlorine is ill‐advised or ineffective and the water needs to be partially or fully changed?” Other impacts of this work included reduced water use utilizing fine mist sprayers as opposed to large-volume flume tanks that require daily filling, draining and cleaning. Additionally, since the water used in the overhead spray system is not recirculated, less chemistry could be used, reducing the overall cost of operation while lower the environmental impact of a packing operation.