how to keep cut yams from turning brown

[phoebe]

I know that you can hold cut potatoes in water, but would a coating of oil do the same thing?  I'm going to make oven baked yam "fries" at a friend's house, but want to do the prep beforehand.  Will tossing them in olive oil keep them from turning brown?

 

[dc sunshine]

I think you really need to do same as potatoes, in acidulated water - either lemon juice or vinegar.  Not sure that oil would work, and may only serve to make them soggy.  Yams and sweet potatoes are notoriously hard to do as fries anyhow.  Go the acid in water IMHO.

 

[amazingrace]

Learn something new every day.  Been cooking for 46 years,  and never knew that yams would turn brown!  I guess I must have been doing something right all these years.  LOL

 

[kirstens]

Using some sort of acidity like lemon, might alter the taste. I use ascorbic acid, a crushed vitamin C powder, when I make a hash brown dish. Once I grate my potatoes, I sprinkle a little of the powder over and they don't turn. You can find this acid at Whole Foods.