lemon has more acid.
Vinegar has a pH range of about 2.4 - 3.4. Apple juice: 2.9 - 3.3 Grapefruit juice: 3 - 3.3 Lemon juice: 2.3 Orange juice: 3 - 4
Lemon Juice especially freshly squeezed; Lime Juice, Grapefruit Juice; Most Vinaigrette dressings; vinegar to name but a few
Lemon has a higher concentration of Citric acid that is why it is more sour.
Oranges are orange and grapefruits are a lighter color. Grapefruits have a more sour taste, while the orange has a fruitier taste.
Haven't tried lemon juice, but a vinegar rinse works like magic - and vinegar's cheaper than lemon juice.
apple juice
You can use lemon juice as a replacement for vinegar in a recipe by using the same amount of lemon juice as the amount of vinegar called for in the recipe. Lemon juice can provide a similar level of acidity and flavor to vinegar in most recipes.
Lemonade, Limeade, Orange juice and Grapefruit juice.
You can substitute vinegar or lime juice for lemon juice in a recipe.
A substitute for lemon juice in recipes can be vinegar or lime juice.
Because of the acids
A suitable alternative for a port substitute in a recipe is grape juice or cranberry juice mixed with a small amount of vinegar or lemon juice to mimic the acidity of port.