I bought some russets at Sam's the first week of this year and they look different from the ones I've purchased before. The new ones are more round than cylindrical plus when I peel them they are firmer and white. Even after grating them and leaving them for a few minutes, they don't change color. Additionally, when putting them through a ricer, the juice comes out clear rather than red as typical for with the previously purchased spuds. Why?
There are lots of Idaho russet varieties; some have a whiter interior or different colored skin. Sometimes the red is due to oxidation, exposure to air. I have found that if I put the shredded potatoes in a mixture of one gallon of water with one teaspoon of concentrated lemon juice, then drain and dry they don't change as quick.