Taste

• Chili sauce gets its piquant flavor from the interplay between the sweetness of the sugar, peppers and tomatoes and the acidity of the vinegar. Lemon juice adds a tart, acidic taste, but it lacks the punch of vinegar. Besides the difference in flavor, substituting lemon juice for vinegar is rarely economically practical. A typical canning recipe that makes 6 quarts of chili sauce calls for 2-1/2 cups vinegar. You'd need more than a dozen lemons to get that much juice or two or three containers of bottled juice. In most cases, vinegar costs much less.

Safety

• If you're refrigerating and using fresh chili sauce immediately, you can safely substitute lemon juice for vinegar. If, on the other hand, you plan to can the chili sauce, you're better off using vinegar. Chili sauce contains low-acid foods, such as tomatoes, peppers and onions. When canned, these alkaline foods create an environment in which the bacteria that causes botulism can grow. Botulism is a serious and potentially fatal food-borne illness. Previously, tomatoes were thought to be a high-acid food that could safely be preserved in a boiling water canner without the addition of acid. In August, 2012, the U.S. Department of Agriculture announced that some tomato varieties, as well as overripe tomatoes or tomatoes harvested after a frost contain less acid, potentially causing illness. The USDA urges consumers to add vinegar, citric acid or lemon juice to any product containing tomatoes. Because chili sauce also contains peppers and onions, it's best to follow any recipe exactly. Do not substitute lemon juice for vinegar unless a recipe explicitly says to.

Type

• Although you shouldn't substitute lemon juice for vinegar, you can choose from several types of vinegar. Avoid using homemade vinegars for canning chili sauce because it's impossible to know how acidic the vinegar is. For safe canning, you need a vinegar that contains 5 percent acidity. Most commercial vinegars fit the bill. White distilled vinegar has a sharp, pungent flavor. It helps preserve the bright flavors of the vegetables. Apple cider has a mellower flavor, but it might cause the vegetables to darken slightly. Buy vinegar by the gallon for the best price.

Considerations

• If you're considering substituting lemon juice for vinegar in chili sauce because you don't like vinegar's sharp flavor, try adding more sugar instead. Added sugar tempers the acidity and tartness of the vinegar. Don't reduce the amount of vinegar called for in the recipe if you are canning it. Doing so will destroy the preservative power of the vinegar, potentially increasing the chances of food-borne illness.