Guide for Inspecting Crayfish: Simple Inspection and Certification Methods Based on Smell and Appearance

2026年4月29日

In the golden autumn of October, it is the time when the crabs are at their fattest. However, in recent years, food safety issues have occurred frequently. How to select high-quality crabs through simple inspection methods and avoid quality risks has become a topic of concern for consumers. This article will introduce practical inspection and verification techniques for crabs in a home environment to help everyone eat with peace of mind. At the same time, for crab farming enterprises, it is recommended to further enhance product quality assurance through factory inspection and certification systems (such as HACCP, organic certification, etc.).
I. Optimal Consumption Period for Male and Female Crabs (Understanding the Product Cycle)
Female Crabs: The meat is at its fattest from mid-October to mid-November. After that, the crab roe becomes harder and the taste deteriorates.
Male crabs: The best time to eat them is from mid-November to mid-December. Those available in late December can still be eaten but should be carefully selected.
Understanding the product cycle helps in determining whether the product is at its best quality period during the inspection process.
II. Five-step Method for Inspecting Crabs (Simple Inspection)
① Smell the Odor - Sensory Inspection
Crabs that grow in good water conditions, feed on live prey, and have not been overused with antibiotics will have a pungent and sweet smell; if they have been fed excessive antibiotics, the sweet smell will disappear and even turn bitter. This is an intuitive inspection indicator.
② Inspecting the belly - Visual inspection
Crabs with a snow-white and clean belly are usually "young crabs" that have just shed their shells. We should try to choose "old crabs" with dark green stains on their bellies, as their meat is usually more plump. This is the key point for visual inspection.
③ Weighing - Weight Inspection
The heavier and more solid the crab feels, the more plump the crab meat is. Even if the crab meat is still somewhat firm, if it feels light and flimsy, it may already have lost much of its flesh. It is recommended to weigh each crab individually or compare the feel to determine, which is a physical inspection.
④ Check the tail - Fatness assessment
Observe the distance between the edge of the crab shell and the umbilicus. The greater the distance, the fuller the crab meat. This feature can assist in determining the maturity level.
⑤ Observe the crab's umbilicus - color inspection
If the apex of the triangular shape of the crab's umbilicus shows a reddish-yellow color, it indicates that the crab's yolk is abundant and the quality is good.
The above five steps can be regarded as the "simple inspection process" for consumers, helping to select high-quality crabs.
III. Factory Inspection and Certification Recommendations (For Aquaculture Enterprises)
To ensure the quality of the Yangtze River crabs from the source, aquaculture enterprises should actively undergo factory inspection audits by third parties, including:
Aquaculture Water Quality Monitoring Record
Control of Feed and Drug Usage
Fishing, temporary holding, and packaging hygiene conditions
And through certification systems (such as MSC, BAP, organic agricultural product certification, etc.) to enhance the credibility of the products.
For purchasers or large catering enterprises, before making bulk purchases, they should entrust professional institutions to conduct inspection and testing, including laboratory tests for microorganisms, veterinary drug residues, heavy metals, etc., to ensure that the products meet food safety standards.
Conclusion
Mastering the above methods for inspecting crabs, combined with understanding the factory inspection and product certification of the breeding enterprises, consumers and purchasers can make more scientific choices of high-quality crabs. We hope this simple inspection guide can help everyone enjoy safe and delicious crabs. For more inspection tips on daily items, please keep following this column.