Birch Cell Cultures (IMAGE) VTT Technical Research Centre of Finland Caption The birch cell culture grown by VTT produces high levels of anthocyanins, which give the cell mass a red colour. VTT grew three different cell lines in its experiments: two red and one green. Credit VTT Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.