Comparative Evaluation of Egg Quality in Response to Temperature Variability: From Farm to Table Exposure Scenarios.

This study aimed to develop appropriate temperature management practices and provide scientific evidence to support the development of sell-by-date guidance for eggs. Washed and unwashed eggs were subjected to storage under six different scenarios, and both types of eggs were stored at temperatures up to 35°C to evaluate the sell-by-date. Despite temperature fluctuations or continuous storage at 30°C for 5 days, subsequent storage at 10°C resulted in significantly higher Haugh unit and yolk index on day 15. These results indicate that refrigerating eggs from retail sales until consumption is effective for egg quality management, despite the exposure of up to 35°C during distribution. In terms of sell-by-date evaluation, washed eggs retained class B quality for an additional 37 days beyond the recommended sell-by-date at 15°C, which is above the regulated storage temperature. However, unwashed eggs maintained class B quality for approximately 20 days at 30°C-35°C, emphasizing the need for sell-by-date guidelines for unwashed eggs. This study is the first to provide appropriate egg-handling practices based on the actual distribution environment in Korea.

Simulation of contamination and elimination of Escherichia coli, Listeria monocytogenes, and Murine norovirus 1 (MNV-1) from the washing process when handling of potatoes.

Root vegetables, which are in close contact with soil, are particularly vulnerable to soil contamination or decay as they can be contaminated from multiple sources, including primary production and processing. This study investigated effective washing conditions to reduce the microbial contamination of potatoes by using soaking and shaking in the washing process. The reduction of Escherichia coli, Listeria monocytogenes, and Murine norovirus 1 (MNV-1) in four washing processes (soaking only, shaking only, combined soaking-shaking I, and combined soaking-shaking I-shaking II) were compared. The numbers of E. coli and L. monocytogenes decreased by 0.55 and 0.49 log CFU/g after shaking only, 1.96 and 1.80 log CFU/g after soaking, 2.07 and 1.67 log CFU/g after soaking-shaking I, and 2.42 and 1.90 log CFU/g after soaking-shaking I-shaking II, respectively. The combined process reduced the microbial contamination more efficiently than shaking only. The reduction of E. coli in the washing process was higher than that of L. monocytogenes by approximately 0.5 logs. MNV-1 showed a reduction in the soaking and shaking steps by 1.34 and 1.98 log GC/100 g, with no significant reduction observed after the combination process. A combined process of soaking-shaking I-shaking II was effective to eliminate E. coli, L. monocytogenes, and MNV-1 from potatoes during the handling and washing process.