Skip to main content
ARS Home » Research » Publications at this Location » Publication #260554
Title: Improved hairline crack detector and poor shell-quality eggs

Author
item Lawrence, Kurt
item Jones, Deana
item Yoon, Seung-Chul
item Heitschmidt, Gerald - Jerry
item ANDERSON, KEN - North Carolina State University

Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/23/2011
Publication Date: 11/23/2011
Citation: Lawrence, K.C., Jones, D.R., Yoon, S.C., Heitschmidt, G.W., Anderson, K.E. 2011. Improved hairline crack detector and poor shell-quality eggs. Applied Engineering in Agriculture. 28:153-158.

Interpretive Summary: Cracks frequently occur throughout various points of egg collection and processing and there are numerous high-speed online commercial crack detectors in use. The accuracy of crack detectors is validated by USDA human graders to ensure that they are in compliance with voluntary grade standards USDA, 2005. However, to validate the high-speed systems, the human graders still rely on hand candling techniques with somewhat antiquated candling lights. In recent years, especially at integrated egg processors with fresh eggs, USDA graders are having difficulty detecting small hairline cracks and microcracks. Lawrence et al. have developed and patented an imaging system to assist the graders in detecting these fresh cracks in table eggs. The system was designed for white table eggs and took about 60 s. to process a set of 15 eggs. In a 1000-egg study with approximately 350 fresh hairline-cracked eggs, the system was 99.6% accurate with only a 0.2% false rejection rate (intact eggs incorrectly classified as cracked). The system had a higher accuracy than any other crack detectors currently in use. The imaging-based system used a high-resolution digital camera to capture an image of 15 eggs in a transparent enclosure. Then a small, quick negative pressure was applied to the enclosure, which opens any eggshell cracks, while a second image was taken. The ratio of the two images was then used to detect any change in the image intensity which was associated with a crack. Jones et al. (2010) showed that the system did not affect egg quality, including Haugh units, albumen height, egg weight, shell strength, vitelline membrane strength and elasticity, and whole-egg total solids, during cold storage. Recently, additional modifications to the system have been made, including enlarging the enclosure to hold 20 eggs, hinging the lid, automating the rollers, adding a case light for external shell quality, and implementing a touch screen with data management software. Additionally, the system was evaluated with intact poor shell-quality eggs to determine if the negative pressure system caused cracks in intact eggs. The purpose of this paper is to report the improvements to the system and the system’s effect on poor shell-quality eggs.

Technical Abstract: Cracks frequently occur throughout various points of egg collection and processing and there are numerous high-speed online commercial crack detectors in use. The accuracy of crack detectors is validated by USDA human graders to ensure that they are in compliance with voluntary grade standards USDA, 2005. However, to validate the high-speed systems, the human graders still rely on hand candling techniques with somewhat antiquated candling lights. In recent years, especially at integrated egg processors with fresh eggs, USDA graders are having difficulty detecting small hairline cracks and microcracks. Lawrence et al. have developed and patented an imaging system to assist the graders in detecting these fresh cracks in table eggs. The system was designed for white table eggs and took about 60 s. to process a set of 15 eggs. In a 1000-egg study with approximately 350 fresh hairline-cracked eggs, the system was 99.6% accurate with only a 0.2% false rejection rate (intact eggs incorrectly classified as cracked). The system had a higher accuracy than any other crack detectors currently in use. The imaging-based system used a high-resolution digital camera to capture an image of 15 eggs in a transparent enclosure. Then a small, quick negative pressure was applied to the enclosure, which opens any eggshell cracks, while a second image was taken. The ratio of the two images was then used to detect any change in the image intensity which was associated with a crack. Jones et al. (2010) showed that the system did not affect egg quality, including Haugh units, albumen height, egg weight, shell strength, vitelline membrane strength and elasticity, and whole-egg total solids, during cold storage. Recently, additional modifications to the system have been made, including enlarging the enclosure to hold 20 eggs, hinging the lid, automating the rollers, adding a case light for external shell quality, and implementing a touch screen with data management software. Additionally, the system was evaluated with intact poor shell-quality eggs to determine if the negative pressure system caused cracks in intact eggs. The purpose of this paper is to report the improvements to the system and the system’s effect on poor shell-quality eggs.