Explainer · Defects and grading
What is a fissured egg, and why can it be Class A?
A fissured egg, also called body-checked, has internal cracks formed inside the hen's uterus that show only on candling. Because the inside of the egg is not exposed, Brazil's agriculture ministry (MAPA) says it can be sold as Class A, even after washing. A surface camera does not see these cracks.
Updated · 3 min read
What is a fissured egg?
A fissured egg has internal cracks, formed inside the hen's uterus, that show only when the egg is examined on candling. MAPA answers this case directly: because the inside of the egg is not exposed, the egg can be sold as Class A (MAPA, question 3).
This comes from MAPA's questions and answers on Ordinance 612. It is official guidance, not the wording of a law, and it describes this case without replacing RIISPOA, which still governs the other grading rules.
Why can a fissured egg be Class A?
What matters in this case is exposure of the inside. MAPA says a fissured egg may be marketed as Class A even after washing, because the inside of the egg is not exposed (MAPA, question 3).
The rule for a broken shell is different. Class A requires a shell and cuticle that are intact (RIISPOA, art. 225), so an egg with a broken shell does not fall in that class. The table shows where each case goes.
| Situation | Destination | Basis |
|---|---|---|
| Internal crack, visible only on candling, inside not exposed | Can be sold as Class A, even after washing | MAPA, question 3 |
| Clean shell, cracked, membrane intact | Industrial processing, as quickly as possible | RIISPOA, art. 227 |
| Dirty and cracked | Discarded immediately | MAPA, question 5 |
How do you identify a fissured egg on the line?
Candling is the method that reveals these cracks. The egg is held against a strong light, and the internal crack shows through the shell. Candling is mandatory in registered Brazilian establishments (RIISPOA, art. 223).
A camera that looks at the surface does not see this defect, because the crack is inside the egg and does not show under normal light. For the difference between the two methods, see candling or computer vision. Hairline cracks and fissured eggs are not the same thing: see hairline cracks in eggs.
Does Vigiovo detect fissured eggs?
No. Vigiovo only detects cracks that are visible in the image, and a fissured crack is not visible to the camera. These eggs still depend on candling.
Vigiovo's role is to complement candling by removing dirty eggs and visibly cracked eggs before it, so candling works on a cleaner batch. Details in how it works.
Frequently asked questions
Is a fissured egg the same as a cracked egg?
- No. A cracked egg has a broken shell, and Class A requires an intact shell (RIISPOA, art. 225). A fissured egg has internal cracks that do not expose the inside, and MAPA says it can be sold as Class A (MAPA, question 3).
Can a fissured egg be sold as Class A?
- According to MAPA, yes, if the cracks are internal, formed in the uterus, visible only on candling and do not expose the inside of the egg. Question 3 of MAPA's guidance on Ordinance 612 says washing does not change this. It is official guidance, not the wording of the law.
Can a camera see a fissured egg?
- No. The cracks sit inside the egg and show only on candling, with light behind the egg. A camera that looks at the shell does not see them, so candling is still required in registered establishments (RIISPOA, art. 223).
Sources
- Perguntas e respostas sobre a Portaria MAPA nº 612/2022 (versão de 05/06/2023), Ministério da Agricultura e Pecuária (MAPA)
- Decreto nº 9.013/2017 (RIISPOA), Presidência da República (Brasil)
How Vigiovo helps
Vigiovo grades eggs on the conveyor as clean, dirty, cracked or unverified, in real time, with deterministic computer vision: every decision comes with the measurements behind it, on an ordinary CPU.