Attention all canjammers! The focus of the February Tigress Can Jam is CARROTS.

Got that?

Yes, carrots.

The Tigress and I made this choice with both excitement and trepidation. The excitement because vegetables are new territory for many water-bath canners; the trepidation because carrots are a low-acid food, and therefore come with certain [...]]]> (Photo from Chris Campbell’s Flickr photostream)

Attention all canjammers! The focus of the February Tigress Can Jam is CARROTS.

Got that?

Yes, carrots.

The Tigress and I made this choice with both excitement and trepidation. The excitement because vegetables are new territory for many water-bath canners; the trepidation because carrots are a low-acid food, and therefore come with certain rules. So. Let’s be clear. No matter what you find on the internets, you absolutely have to add acid to carrots to make them safe to can. In fact, a lot of acid. So much acid, in fact, that the Tigress and I strongly encourage you—nay, insist!—that you start off with a published recipe, and tweak from there. (If you have a home pH meter and/or are a master food preserver, you get a free pass.) Think pickles, relishes, and chutneys. Once you’ve found a recipe you like, feel free to tinker with the spices, the balance of salt and sugar, the exact combination of vegetables, etc. HOWEVER, be sure that you are not reducing the proportion of acid to the food.

Let’s give an entirely hypothetical (as in, don’t try this at home) example. Say you have a recipe that includes 5 cups of carrots, 2 cups of cauliflower, a handful of herbs, 1 T of salt, 1/4 c. of sugar, and 3 cups of vinegar. It would be fine to reduce the cauliflower to 1 cup and add 1 cup of peppers, throw in some mustard seeds, and add more sugar. It would not be OK, though, to just add a cup of peppers without adding more vinegar, because then you’ve lowered the acid content (that is, raised the pH).

Um, if this is at all confusing, that means you should stick with the recipe.

Have fun, be careful, and remember to post your fabulous creations between Sunday, February 14 and midnight, Friday, February 19.

Happy canjamming!

Herewith begins my contribution to the Tigress Can Jam! If you’ve missed it, the canjam is a yearlong canning challenge. Each month, canjammers will be asked to create a water-bath friendly recipe based on a seasonal ingredient. Tigress started us off gently, with citrus. I assumed—rightly as it turns out!—that this would turn into a [...]]]>

Herewith begins my contribution to the Tigress Can Jam! If you’ve missed it, the canjam is a yearlong canning challenge. Each month, canjammers will be asked to create a water-bath friendly recipe based on a seasonal ingredient. Tigress started us off gently, with citrus. I assumed—rightly as it turns out!—that this would turn into a giant marmalade fest, so I was looking for something just a little bit off-center. I found my inspiration in the freezer: a bag of sugared strawberries I put away last May. Technically, I guess that means I’m in violation of the seasonality rule, but given that these were local berries that I picked and stored myself, I hope you’ll agree that it’s in the spirit of the game.

I *love* the way this turned out. I started with a recipe in the Ball Blue Book, but reduced the sugar (I wanted it tarter), added more lemons, kept the peels, and eliminated the pectin…which makes it not really a Blue Book recipe at all. It’s more in the spirit of the tangerine marmalade I made last month, but with lemons and strawberries instead. Now, if you do the Twitter Thing, you’ll know that sugar has recently been a subject of much controversy. I tell you, people: yes, you can reduce the sugar in a marmalade. The safety question in water-bath canning is about acid. Lemons and strawberries have plenty of acid. As both the National Center for Home Food Preservation and the Ball Corporation’s Fresh Preserving Guide make clear, it is not a safety issue to reduce the amount of sugar in fruit preserves. Now, this is not to say that sugar isn’t a preservative—it is, my friends, it is!—but preservation is fundamentally a different question than safety. Sugar preserves taste and helps you get to the gelling point faster. It also prevents mold, which is why jams and preserves that are high in sugar will last longer once you’ve opened them. Sometimes low-sugar preserves aren’t as pretty as high-sugar preserves, and they often have a softer set. Some people, such as the USDA, say that you need to process low-sugar foods longer than high-sugar foods. (But keep in mind that the French don’t process their canned jams at all, and they’re still here.) In this case, though, there’s so much pectin in the lemons that I achieved an excellent set, without pectin and with less sugar than the recipe called for. And since the product is mostly lemons, it’s plenty acidic.

Tweaking canning recipes is a topic that gets plenty of food educators exercised. Those who object are, quite rightly, concerned about your safety. There is a growing consensus among some in the “new” canning community, however, that some of these rules are a tad too rigid. The spirit of the canjam is to improvise within the limits of safety. Part of the challenge of this exercise is to figure out what you can change (spices, fruit combinations, sweeteners) and what you can’t. If you change the recipe, there is, in fact, a chance that something will go wrong. Maybe your jam won’t set. Maybe it will grow mold in 3 months. But you know what? If you see mold, throw it out. Live and learn. And if you’re worried about botulism, don’t, so long as you’re working in a high-acid (i.e., fruit-filled) environment. My personal opinion is that the USDA rules should be taken as a guideline, not as hard and fast rules. Keep in mind that the USDA also recommends that you not eat raw fish or raw eggs, and that meat should be cooked through. Nevertheless, for the record, when you change a recipe, you are doing so at your own risk.

Now that that’s out of the way, let’s get down to business!

Strawberry Lemon Marmalade

1 qt frozen strawberries, in sugar
4 medium lemons, chopped
3 c. sugar
about 3 c. water

1) Wash your lemons. Slice them as thinly as possible, then chop them into pieces. Put them into your jam pot, cover with water, bring to a boil, and simmer 5 minutes. Turn off the heat and let the pan cool. Put a lid on the pan and walk away. Meanwhile, take your berries out of the freezer.

2) The next day, mash the berries and their juices (I use a potato masher). Toss them into the pot along with the sugar. Bring to a boil. Boil it until you’re just at the gelling point. Be careful: there at the end, it gets quite thick rather quickly, and my last jar is a bit thicker than I might like. There’s *lots* of pectin in the pith.

3) Meanwhile, sterilize 4 or 5 half-pint jars and bring your water bath to a boil. Heat new lids. Transfer the hot jam to the hot jars and adjust the two-piece lids. Process in a boiling-water bath canner for 10 minutes.

My version made 4 half pints and 1 4-oz jar, which I’m giving away! Leave a comment by Monday at 8 AM and I’ll select a winner by random number generator. Happy canning!

Sorbets are basically a frozen purée of fruit [...]]]>
My husband—a native New Englander—insists that the time to eat ice cream is winter, not summer. So, now that there’s a chill in the air, he’s craving frozen treats. Since this is an excuse to pull out yet another gadget from the pantry, I am happy to oblige.

Sorbets are basically a frozen purée of fruit in simple syrup, with optional flavors added. The catch is that, since they’re fat free, they tend to freeze into a solid mass of fruit ice. Commerical sorbets contain stabilizers and emulsifiers to solve this problem, but the home cook has a simpler solution: booze. Adding just a single tablespoon of alcohol to a quart of sorbet before you freeze it will keep the texture scoopable by lowering the freezing point. If alcohol is a problem for you, I encourage you to experiment with adding egg whites instead—I’ve never tried it myself, but I’ve seen the technique described in Italian cookbooks.

This recipe is basically the one in David Lebovitz’s The Perfect Scoop, only re-written in a way that makes sense to me. It’s a great book for flavors, but for reasons that aren’t clear to me, I find his directions confusing (too much information, I think). Here’s a streamlined version:

Raspberry Plum Sorbet

1 pound plums
1 c. water
2/3 c. sugar (more or less, to taste)
3/4 c. raspberries (fresh or frozen; if frozen in sugar, add less sugar)
1 T agreeable alcohol (he recommends 1 t. kirsch; I used rum. Something flavorless, like vodka, will always work.)

1) Pit the plums, cut them in large pieces, and cook them in the water until tender. Add the sugar and raspberries; stir to dissolve the sugar.

2) Purée, then strain if the raspberry seeds or plum skims bother you.

3) Chill thoroughly, then freeze it in your ice cream maker.

Tomatoes are an interesting case because they straddle the [...]]]>
As you might have guessed given my giant pile of tomatoes, my next few posts will be all about things you can do with them: roasted tomatoes, roasted tomato salsa, tomato sauce, and mixed pepper sales. But first, let’s do the basics. How do you can tomatoes?

Tomatoes are an interesting case because they straddle the line of low-acid/high-acid food. Technically a fruit, we typically think of them as vegetables. Like most other fruits, however, they are sufficiently acidic that you can can them in a water-bath…but this is where it gets tricky. The USDA recommends that you add 1 tablespoon of lemon juice per pint, just to make sure that the acid levels are high enough. They also recommend that you process them for 40 minutes, which is much longer than I like to cook my tomatoes. The 40-minute recommendation actually came as a shock to me because for years I’ve been working with instructions that say that you only need 15 minutes for a hot pack (more on that below). Apparently, the USDA updated its guidelines in 1989 to reflect growing concerns about food-borne illness. In the case of tomatoes, the biggest concern is salmonella, not botulism.

Personally, I think this is ridiculous. I have been eating 15-minute processed tomatoes my whole life, to no dire effects. Of course, the canned tomatoes that I eat were usually either grown by someone I know or purchased at a local farmer’s market—not conditions likely to breed salmonella. If you decide to go the 15-minute route, you are doing so at your own risk (I assume no liability for your canning choices). I’m just saying that you should use common sense. Wash your hands, wash your food, remove tomato skins, and don’t purchase industrial produce. If you want to be extra-cautious, you can boil your canned tomatoes for 10 minutes when you open the jars. Or you could just follow the USDA’s advice and process them for 40 minutes.

Now: my flip attitude toward the 40-minute rule is only for hot-packed tomatoes. When you can tomatoes, as when you can most fruit, you have a choice. In a cold or raw pack, you put raw fruit in jars and cover them with some sort of boiling liquid. In a hot pack, you bring the fruit to a boil with the liquid, then transfer them to the jars. If you’re using a raw pack, you need to process your tomatoes for 40 minutes. Period. I find that I get better results with a hot pack when I process in a water-bath canner. Fruit shrinks when you heat it. If you’re doing a raw pack, it shrinks in the jars, meaning that you’ll end up with a lot less fruit than you anticipated. When you hot pack, the fruit shrinks before you put it in the jars, which means that you can use fewer jars for the same amount of produce. And, of course, if you’re worried about salmonella, boiling the tomatoes before you can them should help with that.

The alternative is to process your tomatoes in a pressure cooker. This has been my choice lately, both because it uses less energy and because the heat of the pressure cooker will kill just about anything. You can also skip the lemon juice. The catch is that some people feel that the texture of the tomatoes suffer from the heat of the process. I haven’t found that to be the case, but there is an aesthetic issue. Pressure canning usually results in a significant loss of liquid. That’s what’s going on the photos pictured at the top of this post. The jars were full, with only 1/2″ headspace when I put them in the canner, but a week later, they’ve shrunk. Cold vs. hot pack doesn’t seem to make much of a difference, so I don’t bother with heating up the tomatoes first. This is a perfectly normal side-effect of pressure canning and doesn’t affect the safety of the contents, but it freaks some people out. I wouldn’t necessarily give them as gifts. If you’re comfortable with a pressure cooker, though, this is by far the easiest and fasted method.

Long story short: You’ve got 3 basic options for canning tomatoes in water:

Water-bath raw pack: 40 minutes for pints, 45 minutes for quarts, be sure to add lemon juice
Water-bath hot pack: USDA recommends same time as for raw pack. Older instructions say 15 minutes for pints, 20 minutes for quarts. Use lemon juice.
Pressure-canned, hot or raw: USDA recommends 10 minutes at 10 pounds pressure for pints or quarts. Older instructions (use at your own risk) say 0 minutes for pints, 5 minutes for quarts (“0 minutes” simply means bring it to pressure, then turn off the heat).

You’ll need to process them longer if you’re canning in tomato juice. You can find more details and instructions at the National Center for Home Food Preservation. And if all else fails and you have a big freezer, you can just toss peeled tomatoes in freezer bags and call it a day. If you have strong opinions about tomato processing times, please leave your comments below.

When you first asked me this, I thought it was an easy question. So easy, in fact, that I planned on conducting a little kitchen experiment to document both the reaction and its counter-reaction. But things didn’t work out that way, [...]]]> Sometimes garlic turns blue when I cook it. Why? Is it safe to eat?

(Andrew, Philadelphia)

When you first asked me this, I thought it was an easy question. So easy, in fact, that I planned on conducting a little kitchen experiment to document both the reaction and its counter-reaction. But things didn’t work out that way, as I’ll explain below. But first, let’s answer your question. The simplest answer is that garlic contains a set of pigments known as anthocyanins. Under certain conditions, the anthocyanins appear blue-green. They are harmless to eat, and may even go away depending on what you do to the dish next. Harold McGee explained his take on this in his inaugural “Curious Cook” column in the New York Times:

I hear every year from cooks who have been alarmed at seeing normally pale garlic turn bright green and even blue, sometimes when the cloves are pickled whole, sometimes when they’re chopped and cooked with other ingredients. I’d often been puzzled by little blue-green specks when I made garlic bread with loaves of sourdough, but I was really rattled the first time I puréed raw garlic, onion and ginger together in a blender to make chicken in yogurt from Madhur Jaffrey’s “Invitation to Indian Cooking.” When I fried the purée the entire mass turned turquoise blue.

I asked a couple of Indian friends who happen to be plant biologists whether they knew what was going on. They said they had never seen the blue purée, because Indian cooks don’t grind onions and garlic together. They grind or chop them separately and usually fry the onions first. . . .

According to chemists at the China Agricultural University in Beijing, aging the garlic gives it a chance to accumulate large quantities of one of the chemicals that generate the color; fresh garlic doesn’t green much at all. And a strong green color develops in Laba garlic only with acetic acid, the main acid in vinegar (also found in sourdough), because it’s especially effective at breaching internal membranes and mixing the cell chemicals that react together to create the green pigment. The pigment itself turns out to be a close chemical relative of chlorophyll, which gives all green leaves their color.

Two recent reports from the House Foods Corporation in Japan detail exactly how the garlic and garlic-onion pigments develop. Their creators are the same handful of sulfur compounds and enzymes that give the allium family its unique pungent flavors. Under the right conditions these chemicals react with each other and with common amino acids to make pyrroles, clusters of carbon-nitrogen rings. These rings can be linked together into multipyrrole molecules.

The ring structures absorb particular wavelengths of light, and thus appear colored. The two-pyrrole molecule looks red, the three-pyrrole molecule looks blue and the four-pyrrole molecule looks green, as does its cousin tetrapyrrole, the chlorophyll molecule. Like chlorophyll, all the pyrrole pigments are perfectly safe to eat.

Now, I was familiar with the explanation that says that the blue-green apparance is more likely to take place in acid environments. In my own experience I noted that garlic only tends to turn blue when cooked in lemon juice, usually in a metal pan. In fact, the anthocyanin/acid relationship is so strong that you can actually use some vegetables—the classic is red cabbage—as a home pH meter. (You can learn more about the chemistry of red cabbage color changes in this episode of Distillations, a chemistry podcast.)

It was with all of this in mind that I had what I thought was a brilliant idea. If acid turns garlic blue, shouldn’t baking soda, a base, turn it back? So for you, dear readers, I attempted to conduct a scientific experiment.

First I added lemon juice to minced garlic in a glass bowl. Nothing happened.
I transferred the contents to a metal pan. Nothing happened.
I heated it up, thinking maybe the reaction needed a jump start. Still nothing happened.
I added white vinegar, thinking maybe my lemons weren’t strong enough. Nothing happened.
We ate dinner, giving the garlic and acid time to get to know each other. Still no blue.

At this point, I did some additional research and learned that garlic actually turns blue for two reasons. Certainly the anthocyanins are the main culprit. But garlic also contains a lot of sulfate that, when combined with copper, creates copper sulfate, an insoluble, bright turquoise compound. (Again: still fine to eat.) Apparently the trace amounts of copper in water and other foods can be enough to trigger the reaction.

So, I added water. Still no blue.

More research: what food stuffs have high proportions of copper, I wondered? Leafy green vegetables, like kale, chard, and spinach, and certain nuts, like sesame seeds.

I dumped a big pile of sesame seeds into the pot and kept cooking. At this point the kitchen smelled terrible. But still no blue.
Table salt, perhaps, with its iodine content? No go.

This went on and on for about an hour before I finally gave up. So while I can certainly tell you what turns garlic blue, I cannot tell you whether you can turn it back by adding baking soda. If it happens to you, give it a try, and let me know.

Inspired by Mark Bittman’s dictum to eat whole grains, everyday, I mixed this with bulgar for a hearty, healthy, meal. You’ll note that I didn’t say “attractive.” While tasty and nutritious, the look of the final product can only be described as Moosewood circa 1982:

Nevertheless, since it’s an interesting [...]]]> More gems from the garden: turnip greens!

Inspired by Mark Bittman’s dictum to eat whole grains, everyday, I mixed this with bulgar for a hearty, healthy, meal. You’ll note that I didn’t say “attractive.” While tasty and nutritious, the look of the final product can only be described as Moosewood circa 1982:

Nevertheless, since it’s an interesting cooking technique and good for you, too, I thought I’d pass it along. The original version of this came from Paula Wolfert’s Mediterranean Grains and Greens, but I’ve long since lost the recipe. My version was a tad on the bland side—I think hers involved some harissa or dill or something, which would have been nice.

Grains and Greens

1 big bunch turnip greens, sliced very thinly
1 onion, diced
1 T olive oil
1 c. bulgar
salt
about 2 T of water

1) Saute the onion in the oil in a large, deep skillet.

2) Add the salt, the greens, and the bulgar to the pan and turn the heat down to low. Mix everything together very carefully. Your skillet will now look like this:

3) Put the lid on and cook for about 20 minutes. You’ll notice that I didn’t tell you to add any water. That’s not a mistake. Assuming your greens are fresh and that you’ve cleaned them properly, they contain enough moisture to steam the grains without added water. After about 20 minutes or so, check it to make sure that it’s not burning or sticking. You might want to add a couple of tablespoons of water or so, but if it’s still moist in there you might not need it. Let it cook another 10 minutes, turn off the heat, and let it continue to steam for another 10 minutes with the heat off.

Between the turnip greens and the bulgar, you are entitled to feel very self-righteous when you eat this.