are roughly 6 percent acid. The acidity of lemons is almost pure citric acid, while the acidity of lime juice is roughly 4 percent citric and 2 percent malic with a tiny bit of succinic acid. Succinic acid tastes terrible on its own—bitter, metallic, bloody. But in tiny amounts it really improves the flavor of lime juice. It is hard to get; you have to pay exorbitant rates for it at chemical supply houses. Because lemon and lime juices are similar in acidity, they are roughly interchangeable in a recipe from a quantity standpoint, though lime’s malic acid content means acidity lingers longer than lemon’s. Unlike juices from grapefruit, orange, and apple, which can be kept for a couple days or even longer, lemon and lime juices must be used the day they are made. Lime is the most fragile, starting to change the moment it is juiced. I like lime juice best after it has rested for a couple hours. The manner in which you juice a lemon or lime makes a difference. See the Juicers for Limes and Lemons section, here. At 6 percent acidity, lemon and lime juice are fairly concentrated—a good thing for cocktails. Typical sour cocktails will require only ¾ ounce (22.5 ml) of lemon or lime juice to tart them up. Most other juices are not acidic enough, so I often make acid blends that mimic the strength of lime juice to augment my cocktail work. Some examples:
Lime Acid Lime acid is what it says it is: a stand-in for lime juice. I would never use it instead of fruit, but it can be used to bolster fruit with a bit of acidity. For real authenticity, add the succinic, though it can be omitted. INGREDIENTS 94 grams filtered water 4 grams citric acid 2 grams malic acid 0.04 gram succinic acid PROCEDURE Combine all the ingredients. Stir until dissolved.
Lime Acid Orange Orange juice is typically 0.8 percent citric acid—not acidic enough to use in a proper
