Egg inspection and grading resources
Practical guides and references on shell-egg grading: how to identify cracked and dirty eggs, what Brazil's RIISPOA, MAPA Ordinance 612 and the EU rules say, and how candling and computer vision complement each other on the line. Every article cites its official sources and shows when it was last updated.
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Defects and grading
- The egg air cell: the 6 mm limit explainedThe Class A air cell limit of 6 mm and stationary under RIISPOA art. 225 and EU Regulation 2023/2465, why only candling measures it and a camera cannot.
- Blood on eggshells: dirt or an internal defect?How to tell blood stuck to the shell from blood spots inside the egg, what RIISPOA says about each case, and why a surface camera only sees the outside.
- Blood spots in eggs: Class B or unfit?How a blood spot inside the egg decides between Class B and unfit under Brazil's RIISPOA, and why only candling can detect it.
- Calcium deposits on eggshells: how to grade themCalcium deposits are raised pale spots that take an egg out of Class A, which requires a smooth shell. Learn how a camera can mistake them for dirt.
- Egg white quality: what Class A requiresWhat RIISPOA requires of the white for Class A, when a cloudy or stained white takes an egg out of Class A and why only candling checks it.
- Check, broken or leaker: what's the difference?Check, broken and leaker eggs compared: shell, membranes and what Brazil's RIISPOA and 7 CFR 57.1 say about each one, and where each one goes.
- How to identify cracked eggs: types, methods and rulesWhat a cracked egg (check) is, how it differs from a leaker, which methods detect each kind of crack and where cracked eggs must go under the regulations.
- Cracked vs body-checked (fissured) eggsThe difference between a cracked egg and a body-checked (fissured) egg, why only the fissured one can be Class A, who sees each defect and where each goes.
- Dirty eggs: what counts as dirty and how to grade themWhen an egg counts as dirty, whether it can be washed, where it goes under Brazilian and EU rules, and how to measure shell dirt with a camera.
- Dirty vs stained eggs: how to tell them apartHow to tell adhering dirt from a colour stain on the eggshell, what the rules say and how a camera measures each case.
- Double-yolk eggs: how grading detects themHow a double-yolk egg shows up on candling, what RIISPOA says about the yolk, and why a surface camera cannot confirm this defect.
- The eggshell cuticle: what it is and why washing mattersWhat the egg cuticle is, why it matters for Class A and why the washing rule differs between Brazil and the European Union.
- Faecal contamination on eggs: risks and correct destinationWhy faecal dirt makes an egg unfit as it is, when washing is mandatory in Brazil, and what to do with dirty eggs that are also cracked.
- Feathers stuck to eggshells: dirty egg or not?A feather stuck to the shell counts as adhering material under the US dirty egg rule. Loose feathers are a separate case. Here is how to grade each.
- Body-checked ('fissured') eggs: why they can be Class AWhat a body-checked (fissured) egg is, why internal cracks that only show on candling can be sold as Class A, and why cameras miss them.
- Hairline cracks in eggs: why cameras miss themWhat a hairline crack in an egg is, why it does not show under normal light, how candling and acoustic testing reveal it and what Vigiovo detects.
- Leaker eggs: definition, risks and destinationWhat a leaker egg is under 7 CFR 57.1, why RIISPOA makes it unfit for consumption, what a camera can see and how to handle it on the line.
- Misshapen eggs: how to identify an abnormal shapeWhat Brazil's RIISPOA and the EU rule say about normal egg shape, how a camera measures solidity, ellipse fit and proportion, and why off-shape eggs go to review.
- Eggs with off-odours: what the rules sayWhat the RIISPOA and the EU regulation say about eggs with off-odours, why a camera cannot detect smell and how to reduce the risk.
- Rough-shelled eggs: defect or just appearance?Rough shells take an egg out of Brazil's Class A, which requires smooth shells. Learn how to tell roughness from dirt and cracks on the grading line.
- Shell colour variation isn't dirt: how to tell them apartHow to separate natural shell colour and speckling from adhering dirt in egg grading, and why comparing each egg with its own shading avoids false dirty grades.
- Marks and scuffs on eggshells: when they become a defectWhen a cage or belt mark, or a scuff, stops being acceptable in grading, what RIISPOA says about a clean, intact shell, and how lighting changes how the mark looks.
- Soft-shelled and shell-less eggs in gradingHow to recognise soft-shelled or shell-less eggs, why Brazil's RIISPOA takes them out of Class A and what to do with them on the grading line.
- Star cracks: recognising impact damage on the shellHow to recognise a star crack, when it counts as a check rather than a leaker, and why short branching lines are hard to measure from an image.
- Thin-shelled eggs: can they still be Class A?Under MAPA's answer to question 31, a thin-shelled egg can still be Class A in Brazil if the shell has no crack, and why cameras cannot measure thickness.
- The yolk on candling: what a normal yolk looks likeWhat a normal yolk looks like on candling, when yolk position becomes a defect under RIISPOA, and why only candling confirms the yolk.
- Yolk-smeared eggs: how it happens and how to prevent itHow yolk from a broken egg smears its neighbours on the conveyor, why the stain takes an egg out of Class A and how to prevent it.
Standards and regulation
- The self-control programme (Autocontrole) in egg gradingWhat MAPA's answers say the Autocontrole self-control programme must describe in egg grading: flows, downgrading and electronic candling checks.
- Egg grading rules compared: Brazil, EU and USA side-by-side comparison of egg grading rules in Brazil (RIISPOA), the EU (Regulation 2023/2465) and the US (7 CFR 57.1), with a table of terms and classes.
- Brazil's Category A vs the EU's Class ASide-by-side comparison of Brazil's Category A requirements (RIISPOA) and the EU's Class A (Regulation 2023/2465), with wording differences and EU-only rules.
- Brazil's Category A eggs: the five requirementsThe five requirements RIISPOA sets for a Category A egg, explained one by one, with the check that verifies each: surface inspection or candling.
- Class A vs Class B eggs: the practical differencesThe differences between Class A and Class B eggs under Brazil's RIISPOA and the EU standard: criteria side by side, where each class goes and what changes on the line.
- Brazil's Category B eggs: what they are and where they goWhat a Category B egg is under RIISPOA, which defects place an egg in this class, why it goes only to industrial processing and how a downgrade is recorded.
- Disposing of dirty cracked eggs: doing it rightWhat to do with dirty cracked eggs under MAPA and RIISPOA: immediate disposal, breaking into a labelled container, and what can never go into egg products.
- Egg grading in Brazil: the mandatory stepsThe four mandatory egg grading steps in Brazil under RIISPOA (art. 223): shell check, candling, Class A and B grading and packaging hygiene.
- Egg washing rules in Brazil (MAPA Ordinance 612)When washing eggs is mandatory in Brazil, which eggs must not be washed, and how MAPA Ordinance 612 requires the washing to be done.
- Electronic candling: what Brazil's Ordinance 612 allowsAccording to MAPA, Ordinance 612 accepts electronic equipment with results equivalent to traditional candling, provided a validated sampling check is done by hand.
- EU Class A and Class B eggs explainedHow Delegated Regulation (EU) 2023/2465 defines Class A and Class B eggs, when an egg is downgraded and what the 10-day marking deadline is.
- Why the EU bans washing Class A eggsArticle 4(1) of Delegated Regulation (EU) 2023/2465 bars washing or cleaning Class A eggs, with an exception in paragraph 3. The rule and how it compares with Brazil.
- EU egg weight grades: XL, L, M and SThe weight limits for each EU egg grade (XL, L, M and S), how to grade an egg that sits exactly on a limit, and what weight does not decide.
- Poultry farm vs egg processing unit under RIISPOAUnder Brazil's RIISPOA, a poultry farm and an egg processing unit differ in where their eggs come from and what they do with them. See the art. 20 table.
- Mandatory candling in Brazil: what RIISPOA requiresCandling is mandatory under RIISPOA (art. 223, II), with a narrow exception for clean cracked eggs sent to breaking. Read the rules and their limits.
- Egg pre-selection: when the step is mandatoryWhen the egg pre-selection step is mandatory under MAPA's rules, what it separates (clean and dirty cracked eggs) and when it is not required.
- Brazil egg grading rules checklistChecklist for grading eggs in Brazil: each item gives the RIISPOA article or the MAPA answer behind it, so you can check your own line against the rules.
- RIISPOA egg rules: what Brazil's decree requiresPlain-language summary of the RIISPOA articles on eggs: establishment types, grading steps, Class A and B, cracked and unfit eggs, with a link to the guide for each.
- Traceability: separate flows for each type of eggMAPA's answer 27 says each type of egg needs its own production flow. See where to describe those flows and how per-egg records help.
- Eggs unfit for consumption: the 7 cases in art. 500The seven cases in RIISPOA art. 500 that make an egg unfit for human consumption, which are visible from outside and which need candling or breaking.
- Check, leaker, dirty: the US egg definitionsThe 7 CFR 57.1 definitions of check, leaker, dirty and clean and sound shell egg, with plain explanations and Portuguese equivalents for each term.
- To wash or not to wash eggs: Brazil vs the EUWhen washing is mandatory in Brazil, when the EU bans it, and how each rule applies to dirty, clean and cracked eggs.
Inspection technology
- Acoustic crack testing: how the method worksHow acoustic testing finds hairline cracks by tapping the shell and listening for a change in response, what it cannot detect and how to pair it with a camera.
- Crack detection with black-hat and top-hat filtersHow black-hat and top-hat filters bring out fine cracks in the shell, and how Vigiovo turns those lines into a cracked egg grade.
- Egg grader calibration checklistChecklist for calibrating an egg classifier with labelled eggs: setup, labels, limits, a separate test set and a record of the final configuration.
- Calibrating with labelled eggs, step by stepA step-by-step guide to calibrating Vigiovo with a few hundred labelled eggs: what to label, which limits to tune and how close each decision sits to its threshold.
- Candling vs computer vision: what each one detectsCandling compared with camera inspection in egg grading: which defects each detects, speed, record keeping and why the two methods work best together.
- How to choose a camera for egg inspectionHow to choose a camera for egg inspection on the conveyor: fixed position, resolution, frame rate and light, what matters most and what matters less.
- Tracking eggs on a conveyor in real timeHow Vigiovo follows each egg from frame to frame on the conveyor, using nearest-neighbour matching and speed prediction, and why measurement runs only at three checks.
- CPU or GPU for camera egg inspection?CPU or GPU for camera egg inspection: when each processor makes a difference, what usually weighs on cost, and why classical vision runs on an ordinary CPU.
- Deterministic vision vs neural networks for egg gradingDeterministic vision and neural networks compared for egg grading: repeatability, explaining decisions, data needs, hardware and the limits of each method.
- Lighting for camera-based egg inspectionHow to light the conveyor so a camera grades eggs well: diffuse, even light, control of glare, the main cause of false dirty grades, and how to test the setup.
- The distance transform explained with eggsWhat the distance transform is, why the centre of an egg becomes a peak on the map, and how that map helps split touching eggs on a conveyor.
- False positives and false negatives in egg gradingWhat false positives and false negatives mean in egg inspection, why cutting one usually raises the other, and how Vigiovo balances the two.
- Glare and false 'dirty' grades: how to avoid themWhy glare causes false dirty grades, how Vigiovo excludes glare and votes across three measurements, and what to do when a dirty grade turns out to be glare.
- HSV colour segmentation to find eggs on a conveyorHow HSV colour segmentation separates the shell from the conveyor rollers, why HSV separates colour from brightness, and why white shells need other thresholds.
- Human vs camera inspection in egg gradingHuman and camera inspection compared for egg grading: consistency, records, speed, what each one sees and where a person is still needed.
- What image resolution is enough to grade eggs?What camera resolution is enough to grade eggs: why pixels per egg matter, how the egg radius works as a ruler and how to choose a camera for your line.
- Integrating egg grading data with your systemsHow to use an egg grader's per-egg records (class, scores, reasons, measurements) in dashboards and integrations, and what the data cannot tell you.
- Lab colour space for detecting shell stainsHow the Lab colour space separates lightness from colour to find stains of a different colour on the shell, and why Vigiovo excludes glare from that measurement.
- Camera lighting setup checklistChecklist to set up and test the lighting of a camera above the egg conveyor: diffuse light, no glare, stable exposure and a test with clean eggs.
- Mathematical morphology in visual inspectionWhat mathematical morphology is, how erosion, dilation, opening and closing clean an egg mask, and how Vigiovo uses these operations in inspection.
- Per-egg records for grading auditsHow a per-egg record, with class, scores, reasons and measurements, supports grading audits and the equipment verification that MAPA asks for.
- Reproducibility: same image, same resultWhy reproducibility matters for audits and disputes in egg grading, what makes it possible in Vigiovo and what it does not guarantee.
- Tuning rules vs retraining an AI modelA comparison of maintaining an egg grader: tuning rules and thresholds or retraining an AI model, covering cost, explanation, change control and validation.
- Shading surfaces: measuring dirt against the egg itselfWhat a shading surface is, how Vigiovo fits one to each egg by least squares, and how a stain is measured as the residual below it.
- Synthetic data with ground truth: how we measured accuracyHow Vigiovo measures accuracy on generated egg scenes with known ground truth, what the 98.7% and about 95% figures mean and what they do not prove.
- Latency and throughput: how many frames per second you needLatency and throughput in video egg inspection: how long one frame takes in Vigiovo, how many frames per second it processes and how to work out what your line needs.
- Two-of-three voting: why measure each egg three timesHow Vigiovo measures each egg in three checks as it passes on the conveyor and rejects it only when the defect shows up in two, which filters out isolated glare.
- Unverified eggs: when the system shouldn't gradeWhat an unverified egg is in Vigiovo, which shape and area rules mark one, and why the system sends it to manual review instead of guessing a class.
- Visual vs acoustic crack detectionA comparison of visual camera inspection and acoustic testing: what each one detects, why hairline cracks call for the second, and how to combine the two.
- Watershed: separating touching eggs in an imageHow the watershed algorithm separates touching eggs in an image, using the distance transform, one seed per egg and the boundary between each pair, as Vigiovo does.
- White vs brown eggs: what changes for camera inspectionWhy Vigiovo's default thresholds were set for brown and cream shells, what a white or bluish shell changes in the colour mask, and how to recalibrate.
Running the line
- Camera before or after candling?A comparison of placing the camera before or after candling on the grading line: what each position removes first and how pre-selection fits in.
- Camera inspection pilot readiness checklistChecklist for preparing an egg inspection pilot with a camera: camera, light, labelled eggs, computer, manual review and success criteria.
- Where to place the camera on the grading lineHow to place a camera on an egg grading conveyor: a field of view that shows each egg whole, glare-free light and the camera's position relative to candling.
- Clean cracked eggs: sending them to breakingHow to send clean cracked eggs to breaking: what RIISPOA requires, when candling can be optional and why these eggs must never be washed.
- Collection belt maintenance to reduce cracksHow maintaining the egg collection belt reduces cracks: transfer points, signs of wear, handling broken eggs and the role of inspection.
- Egg collection frequency and dirty eggsHow egg collection frequency affects shell dirt, what good practice recommends in general terms and what the regulations require for dirty eggs.
- Checklist to reduce cracked eggsA checklist of actions to reduce cracked eggs in handling, on the belt, in packaging and in monitoring, with the RIISPOA basis and each egg's destination.
- Dirty and cracked egg KPIs per houseHow to calculate dirty and cracked egg rates per house, per batch and per day from per-egg records, and how to use the trend to find the cause.
- Checklist to prevent dirty eggs on the farmA checklist to reduce dirty eggs on the farm: nests and litter, collection, belt and recording, with washing as a last resort and the legal basis for each item.
- Downgrading eggs from Class A to Class BWhen a Class A egg can be downgraded to Class B in Brazil, what MAPA requires to record the decision, and how the European rule differs.
- Inspecting every egg vs samplingA comparison of checking every egg with a camera and checking a sample by hand, what each one guarantees, and why the Brazilian rules ask for both.
- Egg grading line audit checklistA checklist for auditing an egg grading line, with every item tied to the RIISPOA article or MAPA answer that supports it.
- Egg grading line layout: the order of the stepsThe order of steps on an egg grading line: shell assessment, pre-selection, washing, candling, grading and where each type of egg goes.
- How to label eggs to calibrate a graderHow to write labelling rules for eggs, handle borderline cases, use two people to label and set aside a test set before you calibrate.
- Fatigue in manual egg inspectionHow fatigue reduces the consistency of manual egg inspection over the day, how to measure the drop and where the camera and the team complement each other.
- Manual sampling checks for grading equipmentHow to design a manual sampling check for candling equipment: frequency, evaluation and record, and what a surface camera can cover.
- Manual vs automatic grading recordsSpreadsheet or paper log compared with per-egg records: what a grading audit needs to find and what each type of record can prove.
- Training egg grading operatorsWhat an egg grading operator needs to know: the RIISPOA steps, Classes A and B, disposal of dirty and cracked eggs and the review of unverified eggs.
- Reviewing unverified eggs by handWhy some eggs stay unverified, how to find the cause of each one, how to set up a review point and how to use the counts to adjust the line.
- How to run a camera inspection pilotHow to run an egg inspection pilot with a camera on your farm or grading station: setup, labels, comparison with the system's decisions and the report.
- A per-shift quality report for egg gradingThe fields a per-shift egg grading quality report should include: counts per class, the unverified rate, top reasons and the review rhythm.
- Egg grading on small farmsWhat a small poultry farm must do when grading eggs under RIISPOA, which steps are mandatory, and how to start with a camera.
- Washing eggs for industrial processing: good practiceWhich eggs must be washed for industrial processing, how to separate cracked eggs before the washer, and how to keep washing mechanical and traceable.
Egg inspection and grading glossary
Short definitions of egg grading and computer-vision terms: candling, hairline crack, leaker, cuticle, watershed, Lab colour space and more.