Question: how many lemons for 3 tablespoons of zest?
Answer: 1 medium-size lemon = approximately 1 tablespoon of lemon zest = 2 to 3 tablespoons of lemon juice. One (1) cup of lemon juice has only 61 calories (that's less than 4 calories per tablespoon) and no fat. The juice is 5 to 6 percent citric acid.