Influence of Temperature on the Water Retting Process of Hemp (Cannabis sativa L.) Cultivated Under Swedish Climate Conditions

ABSTRACT Hemp has recently received increased interest as a sustainable crop for a multitude of possible uses. This paper focuses on the retting process, which is an important part in the processing of high quality fibre for, e.g., textile products. Water retting process trials were performed on stem plant material from Futura 75 grown at the Lönnstorp Farm research station in the south of Sweden in 2004. Three retting treatments at water temperature 30, 37.5 and 45°C were performed on dried hemp material. Hemp samples were taken from each of the three treatments at 48, 96, 144 and 196 hours. The retting process was investigated and documented by using the change in pectin content and the change in pH value as measures of the rettability. It was not possible to determine an optimal temperature for the retting process by these trials. However it could be concluded that 45°C was too high a water temperature.