The IRI activity of the carrageenan samples was determined in a 49 % (w/w) sucrose solution to which 1 mg/mL carrageenan was added. For sample preparation, sucrose, carrageenan and Milli-Q water were weighed and mixed. The solution was treated in a water bath at a temperature of 60 °C until complete dissolution of the samples (1-2 h). As a control, 49 % (w/w) sucrose solution without the addition of carrageenan was used. 10 µL of the sample solution were placed on a microscopic slide between two cover slips that had been previously glued to the slide at a distance of 8 -10 mm. The sample was covered with a third cover slip and the edges were then sealed with silicone to prevent the solution from evaporating. After drying of the silicone, the microscopic slides were rapidly frozen in liquid nitrogen to ensure that the sample solution reached a glassy state. The samples were stored for 72 h in three small cooling chambers at a temperature of -12.0 °C ± 0.1 °C. The temperature of the cooling chambers was controlled by an external cryostat (FP50, Julabo, Germany). The three cooling chambers were placed inside a glove box, which maintained a temperature of -12.0 °C ± 1.0 °C.