A preliminary study to determine possible treatments that might be used to eliminate or limit value reducing stain in soft maple suggests that rapid processing and treatment with sulfur dioxide gas decreases discoloration, high-temperature drying increases discoloration, and freezing in dry ice prior to processing has no effect.
Wiemann, Michael C.; Knaebe, Mark. 2008. Factors affecting oxidative stain in soft maple (Acer rubrum L.). Research Note FPL-RN-0311. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 3 pages.