Abstract
Etching the required information on fruit and vegetables is an alternative means to label produce. A low energy CO2 laser beam etches the surface with alphanumerical characters showing the contrasting underlying layer. These etched surfaces can promote water loss and potentially allow pathogen entry. Studies were conducted to measure water loss, peel appearance, and potential decay in laser labeled tangerine (Citrus reticulata) during storage. Laser labeled fruit stored at 10 °C and two different relative humidities (RH) (95% and 65%) for 5 weeks showed no increase in decay compared to control non-etched fruit, suggesting that laser labeling does not facilitate decay. These observations were confirmed by experiments where a suspension of Penicillium digitatum spores was applied on fruit surfaces before and after etching. No decay was observed in either case. Laser etching of agar plates covered in Penicillium digitatum spores reduced germination at the lasered areas. Water loss from etched areas and label appearance were determined during storage. Water loss leveled off after one day in storage and appearance deteriorated proportional to laser exposure times and ambient relative humidity.
