How much meat is in that mud crab?

Dr Eric Wang demonstrating the Near-infrared spectrometer

Currently, the common practice for measuring the meat in live mud crabs is for the fisher to apply thumb pressure to the carapace of the mud crab.  The subjective nature of this method of assessment can result in disputes at the boundaries of the grades.

Dr Eric Wang, JCU Senior Lecturer, Electronic Systems and IoT Engineering, together with the Department of Agriculture Fisheries and Forestry (DAFF) are developing a near-infrared spectrometer (NIRS).

Initial studies have proven the NIRS to be an objective science-based technology to determine the meat content of the live mud crab.  The handheld instrument is designed to be taken on fishing boats and be able to quickly grade live crabs, allowing fishers to optimise their catch and return low-grade crabs to the water.

How much meat is in that mud crab? This is most commonly assessed by using thumb pressure applied to the carapace of the mud crab. The subjective nature of this assessment will always result in disputes at the boundaries of the grades. Initial studies by the Department of Agriculture and Fisheries (DAF) has proven the near-infrared spectrometer (NIRS) to be an objective science-based technology to determine the meat content of live mud crabs. This project will develop a handheld instrument designed to be taken on the fishing boat that can quickly grade live crabs, allowing fishers to optimise their catch and return low-grade crabs to the water.

Mud crab claw grades

JCU collaborators at the Department of Agriculture and Fisheries (DAF) were the first in the world to apply non-invasive near-infrared spectroscopy (NIRS) technology to determine the meat content of live mud crabs. Initial studies by DAF and the Fisheries Research and Development Corporation on mud crabs demonstrated the technique was very effective and could help tackle the problem of predicting the meat fullness of mud crabs.

This project will develop a cost-effective, fisherman-friendly, and harsh environment proof handheld near-infrared spectrometer to predict the grade (meat fullness) of mud crabs. It will be specifically designed to be easy to use in the challenging environment of a fishing boat.

The technology will allow the industry to guarantee premium quality mud crab based on meat fullness, increasing profitability and returns along the entire supply chain by ensuring consumer satisfaction and increasing repeat sales.

Near-infrared spectrometer (NIRS) in use

Developing a science-supported assessment technique would standardise grading and allow for a seasonal and/or regional anomalies to be addressed. Ultimately, there is a need for a cost-effective, robust and practical, onboard objective tool to provide consistent and assured grading standards. The developed device could increase profitability and returns along the entire supply chain by ensuring consumer satisfaction and increasing repeat sales.

Project timeline

2020-2022

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