Knowledge Based Bio-Economy


New Sources of Natural, Gastric Stable, Food Additives, Colourants and Novel Functional Foods (Food Processing)

Project acronym: Colorspore

Title of project: New sources of natural, gastric stable, food additives, colourants and novel functional foods

Research area: Food Processing

Contract No: 207948

EU contribution: €2 999 101

Start date: June 2008

Duration: 42 months

Status: finalised

The term functional food is used to describe nutritional ingredients in foodstuffs that contribute to improving consumers’ health and well-being. In recent years, such ingredients have seen considerable growth in the food market. Top of the functional ingredients list are carotenoids, used both as colourants and food additives (vitamins, antioxidants, etc.). One problem with these products is their instability, both on the shelf and during digestion. Recently, gastric-stable bacterial-derived carotenoids have been identified by members of the Colorspore consortium leading to second-generation preparations. These carotenoids, arising from marine organisms, are now the subject of a detailed investigation, as are the bacteria that produce them. The longer-term aim is to develop new, natural, functional additives and ingredients that can replace those manufactured chemically.

The initial aim of the project was to gain a clearer understanding of the recently-discovered carotenoids, to characterise their antioxidant activity and bio-availability, and to assess their potential value as food additives or colourants. This requires the optimisation of efficacy, stability, production processes and formulation. Existing prototypes have been developed as potential food additives and an extensive screening made for new second-generation prototypes made from marine environment sources.

Colorspore directly impacts the food industry by developing new, natural and novel food additives and ingredients that can replace synthetic ones.

It has been widely demonstrated that carotenoids, found in most fruit and vegetables, provide health benefits for the immune system, the eyes and heart, and play a part in the prevention of some cancers.

This has been promoted in some countries by slogans such as ‘five a day’, encouraging consumption from natural sources. However, where diets are restricted by financial or other constraints, supplementation may be beneficial. Carotenoids may also be added to pre-prepared foods, as colourants, or to enable a product to be marketed as having health benefits. Such an approach would appeal to consumers as many people respond to products which are promoted as being natural, rather than synthetic. The use of biological routes should also improve efficacy since they result in structures that are more compatible with ‘life’ as compared to synthetic synthesis where the products may comprise a simple mixture of related molecules.

Variations in carotenoid structure may reduce their metabolic impact or possibly have some deleterious effects. For example, it has been shown in studies of people using synthetic beta-carotene supplements that there is an increased risk of lung cancer, suggesting that the benefits are lost when using synthetic products. Widespread adoption of these routes will also affect the food-ingredient manufacturing industry as in many instances the fermentation or ‘white biotechnology’ industry is distinct from the chemical industry.

Adoption of a natural and sustainable biosynthetic route to produce carotenoids, based on bacterial fermentation, is expected to decrease the amount of pollution caused by current synthetic systems as well as reducing the use of considerable quantities of organic solvents. However, fermentation processes can generate aqueous pollution streams, so the actual impact will depend on the scale of manufacture and the detailed process flow charts.

Investigations based on the inhibition of lipid peroxidation (a process causing cell damage) by these carotenoids using in vitro conditions that mimic gastrointestinal behaviour have established their stability and antioxidant activity. The results include the effects of various metals on these properties, and cover the absorption of bacterial carotenoids by intestinal cells, determined both in vitro using a human intestinal cell line and in vivo in the rat. The results have determined the products’ bio-availability. The nutritional value of these bacteria products has been reported and a risk-benefit assessment made using modern metabolomic technologies as well as traditional toxicology.

Main Results:

The most important result is that of the stability, antioxidant potential, bioavailability and bioaccessibility using the carotenoids found in the HU36 and GB1 bacteria. The consortium showed that the bacterial carotenoids were more stable than other dietary carotenoids (e.g., #-carotene, lycopene, astaxanthin).

The research showed that bacterial carotenoids are better antioxidants against lipid peroxidation than other dietary carotenoids. Regarding bioaccessibility, Colorspore found that absorption of HU36 carotenoids is similar to that of the other dietary carotenoids, while GB1 carotenoids are superior; and that bacterial carotenoids are readily absorbed into the blood, adipose tissue and liver, the latter two being the main storage tissues for carotenoids.

A number of strains from the consortium have been licensed to industrial partners where they will be used as probiotic functional foods or as feeds for aquaculture. This is an important development and demonstrates that the project has produced results transferable to industry.

Website of project:

Coordinator: Simon Cutting,

Organisation: Royal Holloway and Bedford New College, UK,