The new SRM will also help the food industry comply with nutritional labelling requirements and help other researchers conduct risk assessments regarding the consumption of commercial fish.
The reference material consists of five bottles of frozen, homogenised trout from Lake Superior. Each has carefully measured values for about 100 chemical constituents.
Food laboratories can validate their analytical methods and instrument performance by using them to analyse the SRM and comparing their results to the NIST values.
This is the first NIST SRM with certified values for three of the more toxic varieties of polychlorinated biphenyls (PCBs). SRM 1946 also has a certified concentration for methylmercury, a neurotoxin that tends to accumulate in fish and has been the subject of federal advisories warning pregnant women to avoid eating certain fish.
The level in the SRM is near the US Environmental Protection Agency's maximum advisable concentration in freshwater/estuarine fish tissue.
This also is the first NIST food-matrix SRM with values for omega-3 fatty acids, which have been shown to reduce the risk of cardiovascular disease. Other components included on the SRM's certificate include nutritionally significant mono-, poly- and unsaturated fatty acids.
More than 40 federal, state, academic, industrial and foreign labs performed measurements that contributed to the assigned values for the SRM.
A similar research project was recently carried out in the UK, with the objective of developing multi-sensor techniques for monitoring the quality of fish. Scientists wanted to find out how sensory instruments that mimic human senses to take rapid measurements of freshness could be created.
The team claimed that the instrumental measurements they developed could be calibrated to be as good as those of a trained sensory panel.
In order to develop the sensory instruments, the research team had to develop a quality index that characterises the freshness of the fish by combining the measurements taken by the sensors. The team used instruments to take readings in four main areas and these readings were then combined to give an overall measurement of the freshness of the fish.
The four areas were, firstly, texture, where instruments compress the body of the fish to measure its firmness and elasticity. This varies over a number of days in chilled storage and over several months in frozen storage.
Partners from seven different countries - the United Kingdom, Iceland, Norway, Spain, Germany, Italy and Denmark - carried out the MUSTEC project. The initiative received a grant of €730,000 from the Information Society Technology (IST) Programme of the European Union's Framework Programme towards the overall cost of just over €1 million.
"The results of the project will benefit all of us who eat fish as well as the thousands of people who work in the fish processing industry," said Peter Walters, UK National Contact Point for IST within the EU's 6th Framework Programme.
The EU's Framework Programmes are the world's largest, publicly funded, research and technological development programmes. The Sixth Framework Programme (FP6) covers the period 2002-2006 and is the European Union's main instrument for the funding of collaborative research and innovation.
It is open to public and private entities of all sizes in the EU and a number of non-EU countries. It has an overall budget of €19 billion.