I don't know where 159° came from above. Scald temperature ranges from 142° f to about 165°f. Hotter temperatures within this range scald a lot faster but leave the skin more brittle, and it will tear more easily. If you are good at hand plucking, that's not a terribly big problem. If you are using a plucker, the skin will look like you dropped it in a shredder if scalded at hotter temperatures. When I was using a plucker, I always tightly controlled my scalding temperature between 145 and 147° f.