If you have too many tomatoes and not enough ways to use them, make some tomato juice. It’s a moderately labor-intensive process, which may require an investment in a food mill or food press. But the benefits of fresh juice outweigh the minor obstacles. Homemade tomato juice stays fresh in the fridge for about six days, so if you have a lot, can the bulk of it.
Choosing the Tomatoes - Select firm, fresh, vine-ripe ripe tomatoes for your juice. Fleshy tomatoes, such as Roma and plum tomatoes, make thicker juice. Early Girl, Big Boy and Celebrity varieties are juicier, so if you’re making a big batch, it's OK to combine different varieties. Avoid tomatoes from vines that have been killed by frost or those affected by blight since they may contain harmful microorganisms. Wash the tomatoes and cut off the stem and any bruised portions when you’re ready to make juice.
Preparation and Techniques - Dice the tomatoes into less than 1-inch chunks and add them to a stockpot on the stove. Bring the tomatoes to medium-low heat and simmer them until they fall apart. Stir every once in a while so the bottom doesn’t burn. When the tomatoes are very tender, run them through a food mill or food press to remove the solids. A food mill has a crank that, when rotated, presses the tomatoes through a sieve. A food press is a cone-shaped funnel with a stand. The cook uses a wooden pestle to press the tomatoes through the holes in the funnel. If you’re canning any of the juice, return it to the stove and gently boil it for about 10 minutes, stirring frequently.
Keep Some for Later - Tomatoes are low in acid, so you’ll need to add acid to prevent spoilage if you plan to can your juice. The easiest way to do this is to add a teaspoon of lemon juice or citric acid to each of the canning jars. Wash and sterilize your jars, rings and lids. Leave headroom when you fill the jars with juice, and wipe the lips of the jars before you put on the lids. Whether you use a water bath canner or a pressure canner for processing, it’s essential to follow the manufacturer’s directions carefully to avoid spoilage. Because of the variety of ingredients, don't can vegetable juice unless you’re certain you have the right acidity.