Scientists develop natural food colour from algae

Scientists have developed a method of extracting a natural red colorant from the micro-algae Porphyridium cruentum.

A research team from the Universities of Granada has devised the process to obtain the colour, which could prove useful in a number of food and beverage applications.

Many marine algae are rich in proteins with fluorescent properties. They contain a kind of molecules chromophores - that pick up and emit light.

In the case of the species Porphyridium cruentum, the protein known as ficoerithrin confers the micro-algae a reddish colour.

Colorants are used extensively in the food industry to make them more attractive to consumers. B-ficoerithrin is described as "very fluorescent" and its colour "looks like strawberries milkshake's", according to researchers.

The colorant could therefore eventually be used as a natural replacement of existing colorants. Confronted by growing consumer demand for natural and healthy foodstuffs, food makers have increasingly been looking for alternatives to artificial food colours such as Sunset Yellow, Tartrazine and Quinoline Yellow.

Scientists Bermejo Ruperto, of the Universidad de Jaen, Jose Alvarez Pez, of the UGR and Francisco G. Acien Fernandez, Emilio Molina Grima and Jose Ibanez Gonzalez of the Universidad de Almera, have now found a new way of obtaining the B-ficoeritrina protein from this microalgae.

The scientists claim that this method is highly effective. According to Alvarez, the researcher responsible for 'Photochemistry and Photobiology' at the Universidad de Granada, this process is "twice as effective as obtained with the chromatographic method".

The team has already separated and purified amounts of the colour on an "almost industrial preparatory scale".However, the use of a compound as a colorant must be authorised by the regulations currently in force.

The Colours in Food Regulations 1995 have been amended three times (in 2000, 2001 and 2005) to implement Commission Directives 1999/75/EC, 2001/50/EC and 2004/47/EC.

Member States are required to implement the provisions of Directive 2006/33/EC into national legislation by 10 April 2007 and to prohibit products that do not comply with the Directive by this date.

The team of scientists are therefore now dealing with the spectroscopic features of B-ficoerithrin. This will provide vital information about the possible structural changes of the protein when it is subjected to extreme conditions during the production process of foodstuffs.

The researchers has also set in motion an R&D project with a technological innovation company that works on the treatment and commercialisation of microalgae aimed at the sector of aquiculture and the preparation of functional food. A number of commercialised products already use pigments produced from microalgae.

The results of this research work have been included in an article published in the Journal of Chromatography.