Food scientists working in the dairy industry are set to benefit from the development of a powerful new technique for analysing the aroma profile of cheese.

The innovative method, which uses technology developed by Markes International to analyse vapours emitted by a sample, will enable analysts to identify the specific chemical compounds released by different cheeses, even when they are present at trace levels and have low odour thresholds.

With the ability to detect odour and flavour compounds at far lower, and previously undetectable, levels than techniques currently used in the food industry, the method also uses state-of-the-art software to target and identify specific compounds even at the lowest of levels.

"Aroma is an important part of the consumer experience of cheese, and investigations have shown that a range of compounds combine to create their distinctive odours," said Gareth Roberts, Applications Specialist, Markes International.

"Identifying these key aroma components has always been a major challenge for analysts, but we have proven that this technique, coupled with Markes' cutting-edge technology, offers a straightforward and yet powerful assessment of the many chemical compounds that make up the aroma profile of cheese.

"This process can also be used to identify changes in the chemical composition of cheese over time, providing useful data relating to shelf-life and product safety," he added.

In testing the method, analysts at Markes examined the different aroma profiles of full-fat Cheddar, low-fat Cheddar, Comte, Emmental and Brie.

Taking the example of full-fat Cheddar, more than 60 chemical compounds were detected, including: acetic acid, which would be expected to provide a vinegary character to the aroma; butanoic acid, which imparts a more rancid note; and acetoin, which generally has a pleasant buttery odour. 

Also present at significant levels in the Cheddar sample were pentan-2-one, with its fruity contribution, and nonan-2-one, which provides aromas of Gorgonzola and hot milk. Among the trace level compounds found in the Cheddar sample was phenylethyl alcohol, which can provide a pleasant floral odour to cheese.

For further information on the results of this experiment, please see Application Note TDTS 101 at www.bit.ly/Markesapps. Copies are also available by contacting the company on +44 (0)1443 230935 or via enquiries@markes.com 

Markes International is the world leader in thermal desorption technology and innovation, specialising in the manufacture and supply of thermal desorption instrumentation, sampling accessories and consumables for monitoring volatile organic chemicals (VOCs). Markes' global customer base includes major industry, government agencies, academia and the service laboratory sector.