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Inter-laboratory Trial of the Improved HADH Method to detect Previously Frozen Poultry - FA0114

The EC Poultrymeat Marketing Standards Regulation (1906/90)1, which is now incorporated into Council Regulation 1234/20072, requires that poultrymeat (whole birds and portions) is only marketed in certain conditions – ‘fresh’, ‘frozen’ or ‘quick frozen’ and defines the temperature conditions for each category. It is therefore not permitted to sell previously frozen poultrymeat as fresh/chilled

A method which measures the activity of an enzyme (HADH) in meat and poultry has previously been used to distinguish between chilled poultry and that which has been frozen and then thawed. [HADH is a muscle mitochondrial enzyme, ß-hydroxyacyl-CoA-dehydrogenase which is released when the mitochondrial membranes are damaged during freezing and thawing]. In a previous study, the HADH method was applied to chilled and frozen chicken and turkey using the new refrigeration technologies, to assess the extent to which the method can distinguish between these and poultry which has been conventionally chilled or frozen. The study showed that the HADH assay was able to distinguish between poultry that had been frozen, either conventionally or using a new rapid-freezing technique, and fresh or chilled poultry.

In a recent project, procedural changes were made to this method to make the method more reliable and demonstrated that changes in some of the limit values were required. The improved HADH method was validated at LGC but was not collaboratively trialled. In order to assess the robustness of the improved HADH method, this project proposes that it should be validated by undertaking an inter-laboratory trial.

Consumers are defrauded by mislabelling occurring where previously frozen meat is sold as fresh. This will in turn undermine consumer choice and their confidence in food supply chain. Exact figures cannot be determined, as the extent of the problem is not known, however the economic impact on EU retail and industry could be huge, because of the differences in standards and premiums of the affected products on the imported and domestic markets. The outcome of this trial would ensure controls are in place across Europe, to enforce marketing products regulations, and in the long term will ensure a level playing field in the industry and trade.

The consistent application of the improved HADH method will offer protection to consumers and legitimate traders in the EU against the illegal practise of selling previously frozen poultry as ‘fresh’.
Objective 1: Study Design
Previous work at LGC has already shown that the improved HADH method can detect previously frozen (both conventionally and using the Arkansas (Supachill) method) poultry4. Therefore it proposed that only conventional frozen and ‘fresh’ (chilled) chicken samples need to be included in the inter-laboratory trial. As chicken breasts are the most commonly consumed part and the part that is the most difficult to press juice out of, it is proposed that only chicken breasts samples will be used in the CT.

Objective 2: Manufacture of Presses

Objective 3: Practise Analysis by Laboratories

Objective 4: Sample Collection

Objective 5: Sample Transport
Project Documents
• EVID4 - Final project report : FA0114 - Inter-laboratory validation of a method for detecting previously frozen poultrymeat by determination of HADH activity   (1603k)
Time-Scale and Cost
From: 2012

To: 2012

Cost: £89,364
Contractor / Funded Organisations
L G C Limited
Food and Drink              
Food Chain