Why Asparagine Concentrations in Crop Products Are Important

Martin Perkins

2nd February 2017

Acrylamide, Agri-food, Amino Acid, Asparagine, Biological, Biomedical, Crop, FSA, Go for Gold, Maillard, Nigel Halford, Physiological, Protein Hydrolysates, Rothamsted Research,

Nigel Halford of Rothamsted Research has been working with Anatune to develop a fully automated solution for amino acid analysis for both protein hydrolysates and physiological (free) amino acids.

The result is a solution that is rapid, reliable and, with a common sample preparation for a wide range of samples, is highly tolerant of matrix variability.  It is ideally suited to amino acid analysis in both the agri-food sector and biomedical & biological sciences.

This automated approach is of value to R&D and routine food testing laboratories, as the GC-MS system can be used for the analysis of most physiological amino acids.

Nigel explains why this work is so important…

‘The FSA’s Go for Gold campaign has just been launched (23rd January), urging consumers to roast potatoes or toast bread to a golden rather than dark brown colour in order to reduce their exposure to acrylamide.  Acrylamide is a processing contaminant, in other words it is produced in a food when it is cooked or processed, it is not present in the raw, unprocessed food, and is undesirable, in the case of acrylamide because it is potentially harmful.

Acrylamide forms within the Maillard reaction during the frying, baking, roasting or high-temperature processing of cereals, potatoes, coffee and other plant-derived raw materials with all major cereal products, including bread, crispbread, breakfast cereals, cakes and biscuits, being affected, as well as roast potatoes, crisps and chips.  It causes cancer in rodents and is classed as a probable (Group 2a) carcinogen in humans.  Clearly, an undesirable chemical to find in food.

EFSA’s Expert Panel on Contaminants in the Food Chain (CONTAM) has expressed ‘concern’ that dietary acrylamide could have tumour-inducing effects.  As a result, the European Commission is reviewing its risk management measures, which since 2011 have been based on non-mandatory ‘indicative’ levels for the presence of acrylamide in foods.  So the issue is likely to become an even more difficult one for the food industry.

Acrylamide forms predominantly from free (i.e. soluble, non-protein) asparagine within the Maillard reaction.  The reaction also involves reducing sugars, such as glucose, fructose and maltose, and other free amino acids, but in wheat and rye, and probably other cereals, free asparagine concentration is the major determinant of acrylamide-forming potential.  Consequently, the ‘Acrylamide Toolbox’, published by Food Drink Europe, recommends the use of grain with low free asparagine content.  The relationship is more complicated in potato, but asparagine concentration does affect acrylamide formation in some varieties, and biotech approaches to reduce acrylamide formation in potato products in the US have targeted asparagine synthesis.

The current key process for measuring free asparagine and other free amino acids in flour involves gas chromatography-mass spectrometry (GC-MS).  However, the free amino acids in the sample have to be manually prepared with SCX purification and two-step derivatisation.  The manual procedure is a time-consuming and highly operator-dependent process.  A more rapid and reliable method is for immediate, routine, applications in the wheat and other cereal supply chains, from breeders to intake laboratories’.

With Nigel’s expert advice and assistance, we now have a fully automated solution for amino acid analysis that works for both protein hydrolysates and physiological (free) amino acids.

The procedure is both rapid, reliable and with a common sample preparation for a wide range of samples, it is highly matrix tolerant.  It is ideally suited to amino acid analysis in both the Agri-food sector and the biomedical & biological sciences.

The system will be suitable for R&D purposes and also for routine food testing laboratories as this GC-MS based system can be used for the analysis  of most physiological amino acids.

We will be demonstrating the system in a Workshop during the Agilent Environmental and Food Mass Spectrometry User Meeting taking place next week (7th-9th February), at the Hilton Deansgate Hotel in Manchester, UK.   We hope to see you there!!

If you are unable to attend and would like more information on this solution, please contact us on +44 (0)1223 279210 or email: enquiries@anatune.co.uk.