Lillian Smith is ready for a bountiful crop of summer tomatoes.

Right now, her harvest looks a long way off, with only some pale green globes forming on the vines. But she has 25 tomato plants growing in her Rio Linda backyard, enough to keep her family in canned tomatoes through the winter. Plus her homegrown tomatoes will go into sauces, juices, soups and chutneys. Smith may dehydrate some tomatoes, too.

Smith has the answer for any gardener/cook looking for ways to tackle that familiar dilemma: too many tomatoes.

Almost a lost art, canning has come back in style as more people get into vegetable gardening. The interest in farmers markets and pick-your-own farms also fuels this trend as consumers want to preserve their own food.

"Starting two years ago, we saw many more people coming to our classes," said Smith, a UC Cooperative Extension Master Food Preserver, who teaches canning and other preservation techniques. "We saw attendance double, even triple or more. When we used to get 10 people, now we get 30 or 40 in a class."

Tonight, Smith will teach a two-hour class in tomato and pepper preservation at the Cooperative Extension's Sacramento office. The menu includes taco sauce, tomato and apple chutney, fresh vegetable salsa, green pepper jelly and dehydrated tomatoes. Attendees will get recipes and confidence.

"The food safety issue and economics; that's driving the interest in canning," she said. "People want to know how to do it themselves."

Smith experiments with different ways to keep her crop. Last summer, she tried pressure canning. She also made tomato leather. She's always perfecting her techniques.

"I grew up watching my mom do it," Smith said. "I took some food classes in college and bought the 1970s version of the USDA guide. I did a little canning on my own."

A dozen years ago, Smith became a Master Food Preserver, passing the rigorous certification needed to earn that title.

Since her days as mother's helper, Smith discovered a lot has changed in the approach to processing tomatoes, she said.

"Acidity; there's a lot more emphasis on how important that is to food safety," she explained. "Food needs to be processed a lot longer, too. That's why it's important to use up-to-date, reliable recipes."

The Master Food Preservers handle all sorts of fruit and vegetables, but processing tomatoes is always the No. 1 request.

"Tomatoes are the biggest canned item," Smith said. "People have an abundance of tomatoes and they wonder: What do I do now?"

As an alternative to canning, freezing works well, too, with tomatoes and tomato-based products such as pasta sauce.

But, as Smith added, "You only have so much freezer space."

Tomato canning class

What: "Tomatoes and Peppers: Separate and Combined," a guide to canning.

When: 6:30 p.m. today

Where: UC Cooperative Extension auditorium, 4145 Branch Center Road, Sacramento

Admission: $3 for class materials (recipes, etc.); no reservations necessary.

Details: cesacramento.ucdavis.edu or (916) 875-6913.

TOMATO TIPS

In preparation for the harvest to come, here are some basics to remember about processing tomatoes:

• Picking the right tomato: Choose tomatoes that are ripe but still firm with good color and preferably with unblemished skin. They should feel heavy for their size. Round, uniform tomatoes are easier to process than crinkled varieties.

• Average yield: Three pounds of fresh tomatoes are enough to produce one quart of canned tomatoes. A bushel (53 pounds) will yield 15 to 20 quarts of crushed tomatoes or 10 quarts of tomato juice.

• Nutrition: Tomatoes retain most of their vitamins when canned. One cup of raw diced tomatoes has about 32 calories. Tomatoes are high in vitamins A and C as well as antioxidants. In particular, tomatoes are very high in lycopene, which helps repair cell damage and protect the body against cancer.

• How to peel a tomato: The easiest method uses boiling water. First, score the tomato with an "X" opposite the stem end. Immerse the fruit in boiling water for 15 seconds or until the skin begins to crack. Lift out with a slotted spoon, then plunge the tomato into ice water. The skin will then slip right off in your hand.

Master Food Preserver Lillian Smith suggests freezing small tomatoes, up to 2 inches in diameter. When ready to use, remove the frozen tomato from the freezer and run under warm water. The skin will crack and slip off.

• Acidity: Many modern, heirloom and yellow tomatoes have very low acid. That makes them sweeter, but also creates potential for bacteria growth in processing. For food safety, tomatoes needed to be acidified during canning. It also preserves the tomatoes' red color.

Add 1 tablespoon bottled (not fresh) lemon juice per pint. Bottled lemon juice is used because its acidity is consistent.

Citric acid, available in supermarket baking sections, can be used instead. Use 1/4 teaspoon per pint, 1/2 teaspoon per quart.

• No aluminum: Because the acidity in tomatoes reacts with aluminum, use stainless steel or enamel cookware when working with tomatoes.

• How long to process: Canned tomatoes are usually processed in a hot-water bath, which means the jars are boiled with the food inside. (That creates a vacuum that "seals" the jar and keeps bacteria out.) But the processing time varies depending on several factors. Were the tomatoes packed into the jars raw or hot? Were the jars topped off with water or tomato juice?

"That's why it's so important to follow a reliable recipe," Smith said. "I always go back and re-read the directions."

Tomatoes raw-packed with juice take 85 minutes for pints or quarts. Hot-packed crushed tomatoes with no added liquid take 35 minutes to process.

To hot pack: Use a large kettle on medium heat. Start with a few tomatoes and keep adding more fruit as the pot heats up. Once all the tomatoes are in the pot, bring to a boil for five minutes. Then fill the jars, leaving 1/2-inch head space (room for the tomatoes to expand during processing).

To raw pack: Sterilize jars. In the bottom of each jar, put bottled lemon juice (1 tablespoon for pint jars, 2 tablespoons for quarts). Then add tomatoes. They can be crushed, diced or whole. If packing whole, squeeze the peeled tomatoes into the jar. Use a spoon to squeeze out air bubbles. Add more juice from the tomatoes or water to cover the fruit and fill the jars, leaving a 1/2-inch head space.

Tomato juice: Wash and core 6 pounds very ripe tomatoes. Simmer in a large kettle for 20 minutes until very soft. Put through a food mill or sieve. Let stand in a bowl until the light watery liquid rises to the top; discard that top layer and save the rest. Makes about 1 quart juice.

Resources

• www.pickyourown.org: Besides offering locations of pick-your-own tomato farms, this website has a wealth of tomato recipes and tips.

• Master Food Preservers: Part of the UC Cooperative Extension, these local experts are here to help and answer questions. Click on http://cesacramento.ucdavis.edu or call (916) 875-6913.

• National Center for Home Food Preservation: Based at the University of Georgia, this center sets the standards, backed by the USDA. Find many recipes and tips at www.uga.edu/nchfp.

• Ball Canning: With 125 years of experience, the canning experts have put many recipes and tips online at www.freshpreserving.com.

– Debbie Arrington

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Call The Bee's Debbie Arrington, (916) 321-1075.

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