Q: I was given a dessert recipe that included raw egg whites and ¼ cup lemon juice. I remember being told that lemon juice "cooks" raw eggs, but I'm still reluctant to use it. What do you think?
A: I think that's taking a pretty big risk. It's impossible to predict the acidity in a fresh lemon, so you really don't know what the effect would be.
To double-check, I asked Benjamin Chapman, a food safety expert with N.C. State University and the North Carolina Cooperative Extension. He agreed that the acidity in the lemon juice might not affect salmonella if it is already present in the egg. More important, though, salmonella is only one pathogen that can be present in raw egg. Others, such as E.coli O157, are acid-tolerant. So if E.coli was introduced while you were making the dish, it could grow despite the lemon juice.