T2-06 Tracing Temperature Patterns of Cut Leafy Greens during Transportation

Monday, July 29, 2013: 9:45 AM
213D (Charlotte Convention Center)
Ellen Thomas, North Carolina State University, Raleigh, NC
Benjamin Chapman, North Carolina State University, Raleigh, NC
Christopher Gunter, North Carolina State University, Raleigh, NC
Lee-Ann Jaykus, North Carolina State University, Raleigh, NC
Trevor Phister, University of Nottingham, Nottingham, United Kingdom
Introduction: Cut leafy greens (fresh greens that have been chopped, shredded, sliced or torn) have been linked to over 40 outbreaks of foodborne illness since 1990; temperature abuse has been cited as a factor in many of these outbreaks. The 2009 U.S. FDA Model Food Code states that fresh-cut leafy greens be recognized as a time/temperature control for safety (TCS) food and are to be received at food service establishments at or below 5°C.

Purpose: This study determined whether a cost-effective method using commonly available coolers was suitable for transporting cut leafy greens to meet Food Code requirements. Evaluating effectiveness of these transport methods is important for small-scale farmers and processors attempting to meet the transport/delivery requirements.

Methods: Cut leafy greens with a starting temperature of 4°C were held in three different types and sizes of coolers with either ice or ice packs over four hours in simulated transport system to mimic delivery conditions. Temperatures of cut leafy greens were recorded using data loggers. The experiment was replicated in triplicate for each cooler/cooling method. Costs of systems were also evaluated.

Results: All coolers containing ice remained under 5°C for the four hours. Styrofoam coolers with ice packs reached above 5°C after 40 minutes of simulated transport. Cut leafy greens in small coolers with ice packs reached above 5°C after 90 minutes. Cut leafy greens in large coolers with ice packs reached above 5°C after 220 minutes.

Significance: Transporting leafy greens with ice in any of the tested coolers is an effective method to meet Food Code requirements. Transporting using ice packs is suitable if destinations are within 40 minutes of origin. This information is crucial for small farmers as a cost-effective measure to transport fresh-cut leafy greens. Farmers can use this information to make the best decision about transportation method based on their own amount of product and transportation time.