Detection of Spoiled Eggs Using a New-Type Black Light Egg Inspection Unit

Abstract

An automatic black light egg inspection unit was examined to evaluate its performance in combination with an automatic candler-type egg inspection unit using fresh and stored eggs. The combined assessment of the black light unit with the candler-type unit rejected 86.2% of heavily contaminated eggs. The sensory tests carried out at the same time rejected 61.5% of heavily contaminated eggs. Rejection by the sensory testing for eggs contaminated with Pseudomonas, which often occurred when stored at 23 and at 13 C, was not so effective as that by the combined assessment. The combined assessment did not reject eggs contaminated with certain Enterobacteriaceae that were frequently found in the eggs stored at 23 C. No methods used in this study could detect the eggs contaminated with Alcaligenes, the growth of which produced no change in the appearance or odor of the egg contents.In heavily contaminated eggs, the number of Pseudomonas-contaminated eggs (63) was larger than that of Enterobacteriaceae-contaminated eggs (28). For this reason, combined assessment was superior to the sensory tests.