Substitute for Lime Juice

Lime juice does two jobs at once. Its acid balances fish sauce, chile and sugar in Southeast Asian dressings, sets key lime pie, firms raw fish and keeps guacamole green for a while. Its slightly bitter, floral aroma is what makes a dish taste of lime rather than just sour. Decide which of the two the recipe depends on before choosing a swap.

Mexican and Latin American dishes

In guacamole, pico de gallo, ceviche and elote, lemon juice is the practical swap at the same amount. Taste the salt again afterward, since lemon reads milder and the dish can seem underseasoned. For marinades for carne asada or pollo asado, bottled lime juice or white wine vinegar at half volume work because garlic, chile and the grill dominate.

Thai and Vietnamese cooking

Nuoc cham, larb, som tam and Thai beef salad rely on a balance of sour, salty and sweet. Rice vinegar keeps that balance better than sharper vinegars. Marukan lists its plain rice vinegar at 4.3% acidity, at the low end for vinegar, which is why it takes about two-thirds the volume of lime instead of the half-measure extension charts give for vinegar in general. Lemon juice also works, at the same amount. Rebalance with sugar and fish sauce after swapping, a little at a time.

Baking and desserts

Key lime pie, lime bars and lime curd depend on acid to thicken condensed milk or eggs, and lemon juice or bottled lime juice provide it in equal measure. Lime-flavored cakes get most of their flavor from zest; if only juice is missing, a little citric acid solution adds the tartness without thinning a glaze.

When not to substitute

Margaritas, mojitos, a squeeze of fresh lime over tacos or pho, and Indian lime pickle are about fresh lime aroma; lemon makes a recognizably different version and vinegar does not belong. For home-canned salsa and tomatoes, only bottled juice is acceptable, as fresh limes have unpredictable acidity.

Common mistakes

• Replacing lime with distilled white vinegar in nuoc cham. The harsh edge overwhelms the fish sauce; rice vinegar is the milder choice.
• Not re-tasting after the swap. Lemon tastes rounder, so dressings often need an extra squeeze or pinch of salt.
• Using sweetened lime cordial. The added sugar throws off marinades and dressings.
• Expecting acid to make raw fish safe. Ceviche texture changes, but the fish must still be raw-quality.