Introduction: How to Preserve a Bushel of Tomatoes in a Day

I ordered a bushel of tomatoes since a cool, rainy summer was giving me less than I wanted for the winter from the 22 plants I had in my garden. The catch: they were to arrive on Thursday morning and I was going away for a week on Saturday (and I had to pack too!).

But, hey, I had the tools, the space, and the experience from past tomato sessions to draw on. I'd pick up the tomatoes and start. Hopefully I'd be done sometime on Friday.

I got them done in six hours and step-by-step, here is how I did it.

Step 1: Tools and Materials

These are tools I had on hand. Only one was a "new to me" purchase this year: a giant colander for 25 cents from a yard sale.

1. Grill - fire-roasting is so much nicer than scalding/skinning, and I love the flavor imparted to the final product.
2. Table(s) - if you don't have "wings" on your grill, you'll need an additional table.
3. Colander - this year's was huge; I've used a smaller one in the past.
4. Bowl to hold the colander (and drained tomato stock)
5. Slicing knife - to break up the roasted tomatoes to release juice
6. Masher - to crush the roasted tomatoes to further release the juice
7. Spoon - for transferring crushed tomatoes to the tomato mill
8. Tongs - for turning the tomatoes (doing so with fingers not recommended) and transferring them from the grill to the colander.
9. Tomato mill - this is a high capacity one that I got last year for about $40 from Lee Valley. This is much easier to use than the round metal ones you often see in thrift stores. While plastic, it is high quality and I expect to use it the rest of my life.
10. Tomato debris catcher - for my set-up something rectangular worked best.
11. Kitchen compost bin - for the debris after the pulp extraction
12. Pots - one for collecting the tomato pulp and one for collecting the tomato stock
13. Water boil canner - a tall stock pot with a cake rack in the bottom of it works fine
14. Jar lifter - indispensable to safely move hot jars in and out of the canner
15. Tongs - for taking jar lids out of hot water
16. Blender (or food processer) - to puree the sauce and stock enhancements.

1 A bushel of tomatoes
2. Sauce ingredients: I used garlic, hot peppers, red wine vinegar, fresh oregano, fresh basil, salt
3. Stock enhancing ingredients: I used parsley, lemon thyme, fresh yellow oregano, salt, lemon juice.

Step 2: Roasting the Tomatoes

Tomato season is usually still the heat of summer. It certainly was the Thursday I got my tomatoes. I hefted the bushel box from my car trunk to a stool on my kitchen deck -- thankfully only a few steps. I had a tarp roof on the deck and an umbrella over the deck table, so there was some shade. Then I set up everything to do as much as possible outside.

I really hate scalding and skinning tomatoes. I like opening a jar of sauce and just using it in the winter, so I make sauce. I really like the taste of fire-roasted tomatoes. I've also found that if you let them sit, a wonderful tomato stock drains from them -- and there is that much less liquid to boil off  your sauce!

This year I set up an assembly line: roast, extract stock, extract pulp, dump debris. Through the door to the right of the grill is the kitchen stove and I have a movable island that I use for my jar-filling station. The deck table held the pots for pulp and stock.

We have an Australian barbeque that has a grill on one side and a griddle on the other. I put a marble tile on the griddle to hold the bowl and colander for the stock extraction station. Another marble tile went on the wooden side rack to hold the tomato mill, which has a suction grip that worked fine on the glossy tile surface. The domed cover for our grill is a repurposed large stainless steel bowl with an attached knob. With a conventional grill, you'll need another small table to hold your extraction stations. You will probably, however, be able to roast twice as many tomatoes at a time as I could.

The Romas I got were about the size of tennis balls. These take longer to roast than paste tomatoes the size of plums, which is what I usually get from my garden. Once I got going, I used the roasting time to extract the stock, mill the pulp, gather the other sauce ingredients and prepare them.

Use a high setting on your grill. You want the skins slightly blackened and the insides soft. The first side takes longer. Once you turn your tomatoes, the second side browns quickly and splits. If you have mixed sizes, try to sort by size when loading the grill. Then you can toss them all into the colander at the same time.

Step 3: Extracting the Tomato Stock

Tomato stock is the liquid from the tomatoes. In conventional sauce making, the water in this is boiled away (into the air of your house -- great stuff on an already hot, humid day!). You might argue that the "essences" of tomato are kept in the sauce. I'd argue that I like a "fresher" taste to my sauce even though it is canned.

To extract the stock:
1. Roast your tomatoes.
2. Put them in the colander and cut through them to start liquid release. Cutting is optional with small tomatoes, but recommended for those tennis ball size or beyond.
3. Mash while still hot and let them sit to drip and cool before putting them through the tomato mill. You can stir them a little to encourage the liquid to go to the sides and bottom of the colander, but not so much that you put a lot of pulp into the stock.
4. When the level of stock reaches the bottom of the colander, pour the bowl's contents into a pot (if you are processing that day) or into large containers to store in the fridge or freezer for later processing. I elected to process that day since I was planning to freeze pulp for some meat sauces later in September.

Whatever do you use it for?
1. Soup
2. Cooking rice
3. Anywhere else you would use a vegetable stock.

I usually add whatever green herbs I have on hand, starting with parsley (I now grow parsley to have it on hand for tomato stock and also a salted vegetable stock I put up). I know I'll be adding lemon juice to assure acidity, so lemon thyme combines nicely with that. Garlic chives are rampant in my kitchen garden, so I also add those. They have a more delicate flavor than garlic itself. I like to add celery if I have it at hand. You can also go Italian and use basil and oregano. Use combos you like for soups.

When I've accumulated enough for 5 or 6 jars, I take a cup of the stock and blend up the herbs with it. I add that to the pot of stock with some salt to taste. I simmer it about 5 minutes before putting it into pint jars (with a tablespoon of lemon juice in the bottom of each jar). I process those in a water bath for 35 minutes.

Step 4: Extracting the Pulp

The tomato mill I use is an Italian design. It has a high capacity and is very efficient. The thing can be operated one handedly (I had to last fall when I broke my left wrist). It is also easy to clean -- once you figure out how to get the milling piece apart. If you want one (assuming tomatoes are a large and vital part of your harvesting life), lots of options come up in Google. I got mine from Lee Valley, a Canadian firm that also ships to the States.

You can also use the "crush and cook" method to prepare tomatoes for a tomato mill. Cut up a few tomatoes to start and put them into a pan over medium-high heat. Crush them with a masher and continue to add tomatoes (small ones can be incorporated whole; you'll probably want to cut up large ones unless you are tall with good arm strength) as the first ones juice and soften.

Spoon the cooked tomatoes into the mill's hopper. Have the bowl in place to catch the pulp and something in place to catch the debris. I found that a silicon bread pan works great for this: it fits under the debris spout nicely, has a good capacity, and is easy to empty into the hopper for a second run and into the compost bin when you're done. With my mill, there is still some pulp in the debris after the first run. I put it back into the hopper and usually get another half cup of pulp from the full hopper load.

I periodically empty the pulp collected to the pot in which I cook the sauce.

Step 5: Cooking the Sauce

I started to cook down the sauce once I had half of a 5 qt pot. This meant I had to have another pot out on the deck to collect more pulp as I continued to roast and mill. I used a spatter screen to cover the pot so that steam could escape but sauce would not pop out all over the stove and me as the sauce thickened and the level of sauce in the pot rose as I added more pulp.

Between roasting and milling more tomatoes, I prepped the rest of the sauce ingredients. We like a zesty sauce so I added a cut up cayenne pepper to the usual garlic, basil, and oregano. I put a cup of pulp in the blender and pureed the herbs and pepper with it. I put in a half-cup of red wine vinegar for acidity and flavor contribution and salted to taste. During the final simmer (with all the pulp I was going to add), I put clean jars in the water bath canner with water to fill and cover and set that to heat to nearly a boil. I put the jar lids in a small metal bowl to cover with hot water from the canner once I got the jars out.

I use a ladle and jar funnel (another find from Lee Valley, but I've also seen them in stores that have canning supplies) to fill the jars, a small clean sponge to assure there's nothing on the jar lip, and my jar lifter to put the jars in the canner once the jar rings are on. I made and processed 6 pints of sauce at a time. Tomato sauce requires thirty five minutes of processing. I have a hand-wound timer that I use when I'm canning. I set it once the canner is boiling and can carry it with me.

I washed the pot and brought it back out to accumulate more pulp. When the sauce was processed, I had enough stock accumulated to make up 6 pints. The clean jars for that quickly heated in the water that the sauce jars came out of and were ready to fill by the time the stock had simmered.

I had lunch while beginning the simmer of my second batch of sauce. I was able to do another quick turnaround of jars once the stock was processed and the tomato sauce was finishing up.

I made 12 pints of tomato sauce in all.

Step 6: Finishing Up

After the second batch of sauce was done, so was all the tomato roasting. The box was empty! I decided to go ahead and process a second batch of stock so I wouldn't have to store it in the freezer. I did have six quarts of pulp to freeze. I was planning to use those for canned chili meat and spaghetti meat sauce once I got some grass-fed beef later in September.

Once I got the stock jars in the canner, I began serious cleanup: four pots, a large colander, a large bowl, a blender, spoons, a ladle, a masher, knives, and the tomato mill. The counter beside the double sink was holding the day's results, one half of the double sink held a loaded drainer, and the overflow went out onto the deck rails in the sunshine.

From the bushel of Roma tomatoes I got:
- 12 pints of tomato sauce
- 12 pints of tomato stock
- 6 quarts of tomato pulp (for the freezer)
- a jar of extra sauce (for immediate use)
- a jar of extra pulp (for the fridge and later use)

Even with trimmings from the celery and herbs I used in the stock, I didn't fill my two quart kitchen compost bin.

I started processing a little after 9:30 in the morning and was finished at 3:30 in the afternoon.