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E 406 407 substance agar main function thickener, vegetable gum, stabilizer, gelling agent carrageenan 407a processed eucheuma seaweed thickener, vegetable gum, stabilizer, gelling agent, emulsifier thickener, vegetable gum, stabilizer, gelling agent, emulsifier Landscape of marine biotechnology infrastructures and technologies in the food sector Various methods utilised to extract the relevant compound to be used in functional foods, food ingredients, and feeds. Some specific examples are given below:  Fucoidan must be extracted from its source of brown seaweed using an acid such as hydrochloric acid, acetic acid or (as with the organic method) citric acid. Filtration and salt removal also need to be carried out164;  For Fucoxanthin the seaweed is cultured in a controlled environment so that the quantities of extra nitrogen and light can be monitored. Nitrogen and light determine the levels of Fucoxanthin that emerges as the seaweed grows. Fucoxanthin is then extracted and then purified through silica gel column chromatography and preparation high performance liquid chromatography (prep-HPLC)165. Extraction efficiency is something that still needs to be improved in order to increase the viability of mass production of Fucoxanthin;  For alginates seaweed is collected, washed dried and crushed. It is then swelled in acidic water. Extraction of sodium alginate then takes place through the addition of caustic soda. The alginate in seaweed is extracted first by conversion to water-soluble Sodium alginate. The aqueous alginate solution is then isolated first through a clarification procedure. This solution is diluted since it is highly viscous, by adding a large amount of water. To separate the Sodium alginate from the fibrous seaweed residue such as cellulose, the seaweed extract is filtrated. The ‘acid precipitation method’ of the ‘calcium method’ are used to extract alginic acid, which is then dehydrated and pulverised. Several different chemical processes, such as ion-exchange and esterification, may also be used to arrive at the final alginate product. The extraction technologies used in the current producing countries are basic. More effective production process based on the use of a twin screw extruder is proposed by INFRIMER and others166;  For agar there are several methods of production. However, the main method involves dissolving the agar from the seaweed using hot water. After this, the agar itself is separated from the cell wall by filtration and isolating the agar from the dilute solution. This isolation may be done by cutting the gel into strips and allowing it to freeze overnight and thaw out the next day in the sun. Freezing and cooling continues until a dry strip is formed. ‘Gel pressing’ and ‘roller drying’ are more large-scale techniques that are used at the industrial scale to achieve similar effects. Additionally, alkali treatment can make pressing easier. Agar is then sold in strip or block format167;  The four basic processes involved in Carrageenan extraction are: alcohol precipitation, KCl (Potassium chloride) precipitation (or gel press), danisco process, and semi refined process. The traditional method of Carrageenan extraction is alcohol precipitation168. Chitosan is produced form waste of several types of crustaceans by crushing, decalcification, deproteination and deacetylation. 164 http://www.zenmony.com/fucoidan-manufacturing-process-a22/ 165 http://www.mdpi.com/1660-3397/11/7/2667 166 Vauchel et al. (IFREMER): A New Process for Extracting Alginates from Laminaria digitata : Reactive Extrusion (2008) 167 http://www.cybercolloids.net/information/technical-articles/introduction-agar-production 168 http://www.cybercolloids.net/information/technical-articles/introduction-carrageenan-production Study in support of Impact Assessment work on Blue Biotechnology 135

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