Tannic acid (Gallotannins)


Today Ajinomoto OmniChem NaturalSpecialities has become one of the leading suppliers of hydrolysable tannins worldwide, and has acquired significant expertise in the tannic acid chemistry and the industrial application of hydrolysable tannins.
Ajinomoto OmniChem is the only company in the world covering almost the entire range of raw materials available to industry, allowing us to market a very broad product portfolio. Not only does our range include tannins originating from a single plant source but also blended products are available. This allows us to offer the best technical solution for any given application.

Our tannins are 100 % natural materials extracted from renewable plant materials using full c-GMP production facilities.


Seguin introduced the word "tannin" in 1796 indicating materials suitable for converting animal hides into leather. Nowadays the words tannin or tannic acid cover a wide variety of products usually classified 3 families: proanthocyanidins (or catechins)
ellagi-tannins and gallo-tannins.
Proanthocyanidins are also called condensed tannins, while the so-called gallo-tannins and ellagi-tannins also known as hydrolysable tannins.
In nature condensed tannins are the most abundant and can be found - usually at low concentrations - in a large number of plant genera. Although condensed tannins represent more than 95 % of total world production they are usually applied as crude low quality extracts in applications such as leather production and the production of adhesives for plywood. Due to their dark colour, lower molecular weight and high level of impurities, they are not suitable for higher quality application (ie food and pharma).
Hydrolysable tannins (ie gallotannins) are far less abundant and only a limited number of plants contain sufficient amounts of these product to be of commercial value.
Where high degree of activity, high purity and a low influence on colour are important, hydrolysable tannins are the products of choice.
Depending upon the application choosing the right tannic acid with an appropriate molecular weight distribution has a major influence on final performance.
Furthermore the unique tannic acid chemistry provides a number of unusual properties combined in one molecule:

  • Strong metal complexing
  • Complex formation with proteins, alkaloids and certain polysaccharides
  • Strong affinity towards polyamides
  • Strong anti-oxidizing properties

Raw materials

Only a limited number of plant materials are of commercial interest for hydrolysable tannin production. Major re-strictions are availability of the plant material and the amount of tannin present. A content of at least 20 % is the strict minimum for commercial extraction of tannins having technical or food applications.
Exceptions are grape seed tannins having abundance in the raw material of less than 5 %. The sales price of these products is however significantly higher allowing the use of a raw material having a low active ingredient content.
Typical raw materials include: Chinese gallnuts, alepo nuts, sumac leaves and tara pods.


A high amount of flexibility in our production facility allows us to adapt our post purification of the crude tannin extract to the requirements of the end user. This allows us to offer the best technical solution for any given application.
For the production of its hydrolysable tannins OmniChem uses a continuous solid/liquid extraction line. Thus a crude extract is obtained that is further purified using liquid/liquid extraction. By careful selection of the extraction solvents a variety of impurities can be removed. If necessary further purification steps involving the use of ion exchange resins, active carbons and filtration can be used. The purified extract is spray-dried and a granular product is obtained using fluidised bed technology.
In a world where environmentally sound solutions are becoming more and more important there is a very bright future for products like the OmniChem tannins. Our tannins are 100 % natural materials extracted from renewable plant sources using
full c-GMP production facilities.