Refined and Filtered Carrageenan-Production Method
There are two basic and different production methods of carrageenan, which is based on completely different principles. The first method which was used until the 1970s to 1980s wherein the carrageenan was extracted from seaweed into a watery solution, the residue of seawood is eliminated with the help of the filtration process and then it is extracted from the solution.
In the second method, everything is washed out of the seaweed, which dissolves in water and alkali, leaving insoluble matter and carrageenan behind.
Refined and Filtered Carrageenan
The refined form is actually the original form of the ingredient (carrageenan) until the early 1970s-1980s and was called as carrageenan. Now, it is sometimes called filtered carrageenan. Initially it was made out of Chondrus crispus, but now the same process is used to all types of algae.
The seaweed is first washed thoroughly to remove the salts, and foreign matter. Then, it is heated with alkali water, like sodium hydroxide for hours together, for a certain period of time depending upon by setting small scale tests or experience.
Alkali is applied because it results in a chemical change that causes improved gel strength in the end product. It eliminates some amount of sulphate groups from the existing molecules and enhances 3, 6-AG formation.
The centrifugation process is used to remove the seaweed that doesn’t get dissolve or through a filtration or a coarse or a combination of both. The solution is filtered again, using a filter aid in a pressure filter, which stops the filter cloth getting blocked due to gelatinous particles.
At this stage, the solution that is extracted contains only 1-2% of carrageenan and is normally concentrated to2%-3% by ultra filtration and vacuum distillation. The processor will now get a clear solution of the ingredient (carrageenan) and again there are two basic methods of obtaining it.