[Methanol formation in vitro and in vivo (methanol formation after pectin administration)]

1. In the course of 34 days the detectable methanol concentration in freshly squeezed grapefruit and organ juices as well as in grapefruit and orange juice mixes increased to a maximum level of approximately 600 mg/kg. This increase could already be detected at the beginning of the examination i.e. as early as 1 or 2 days after squeezing the fruit juices. At the beginning of the experiments the methanol concentrations were between 10 and 270 mg/kg. 2. After the consumption of pectin (40 g on one day and 2 x 40 g on two days) blood or serum-methanol values respectively were observed which were clearly above the level of chronic alcohol abuse (10 mg/kg). After the ingestion of ethanol (0.5 g/kg bodyweight) the serum-methanol concentration increased even further.