Apple #688: The Magic That Is Garlic

Let's talk about garlic.

It makes our breath stink to high heaven, yet we love to eat it.  Some cultures have denigrated others for being "garlic eaters," yet studies show time and again, the savory foods the majority of us like best are those with garlic in them.  The bulb is a great big knobby thing that doesn't look at all enticing or even edible, but we eat so much of it that 500 million pounds of garlic are planted each year in the United States alone.

Such a miraculous plant deserves an Apple.



What do you think when you see garlic? Pew, that stinks?  Or Mmm, delicious?
(Photo from Care2)

What Is It?

• Garlic is first of all an herb.  

• Herbs are plants used for their flavor, but usually herbs (as distinct from spices) are those whose leaves we use.  Think of basil or oregano or rosemary.  

• But with garlic, we usually don't use the leafy parts (though you can) but rather the bulbs. 

• Still, this bulb is considered an herb.

This image is a bit blurry, but the parts of the garlic plant are labeled with general terms. The stalk is more officially known as the scape.  Usually farmers cut this off and throw it away, but some are starting to sell the scape at farmers' markets. You can use scapes as you might use chives.
(Diagram from Rickertville Farm)

• Garlic is a member of the lily family, and within that, in the genus Allium.  It lives there with its fellow stinky relatives -- the onion, the leek, the wild ramps.

The Stink

• Everyone knows garlic is stinky.  But actually, garlic has no smell at all -- until it is cut into or damaged.

• Left whole, allowed to grow merrily and do its thing in the soil, garlic would be offensive to no one.  But once its cells are damaged, a key compound called alliin morphs into its evil twin allicin, and that seeks out its best friend sulfur, and then everything gets really stinky really fast.

Garlic intact in the bulb: not stinky at all.  Garlic smashed and chopped into tiny pieces: very stinky.
(Photo by the Apple Lady)

• In fact, 4 sulfur-containing compounds are created when garlic is cut or crushed or smashed or bitten into or otherwise damaged: 
• diallyl disulfide
• allyl methyl sulfide
• allyl mercaptan
• allyl methyl sulfide

• 3 of these 4 compounds your body can digest and get rid of pretty quickly.  The 4th, allyl methyl sulfide, lingers.  For as long as 2 whole days, in some people.  Some sources say it even gets into the lung tissue and that's why it takes so long to go away.

• So that's what you're smelling on your partner's breath 2 days after you shared that delicious dish of really garlicky spaghetti: the old allyl methyl sulfide, who never knows when it's time to leave a party.

(Image from Healthy Fellow)

• Side note: the fact that garlic doesn't stink until you break it open makes me wonder if ropes of garlic would really be all that effective against vampires.  Probably a better vampire repellant would be crushing and smearing fresh garlic all over yourself. Of course, you'd probably be repelling everybody else for a half-mile radius, too.

• By the way, there are lots of suggestions for getting rid of garlic breath.  Such suggestions include:
• eating parsley
• drinking a glass of milk
• drinking green tea
• eating button mushrooms (cooked or uncooked, I'm not sure)
• eating raw kiwi
• eating eggplant
• mixing your garlic-laden foods with lemon juice or other citric acid beforehand

• But based on what I've read, these suggestions seem to provide minimal benefits, if any.

• One thing I do know from experience is how to get the garlic smell off your hands: wipe your stinky garlic fingers on stainless steel.  This could be a butter knife, your kitchen faucet, whatever is handy.  Neutralizes the smell better than soap & water alone. 

This person is sort of caressing her water faucet. If you've got garlic stink on your hands, you won't want to caress the faucet, you'll want to rub your fingers & hands all over it.  That will remove the smell very well. No need to be coy about it.
(Photo from Delta Lahara Single Handle Lavatory Faucet available on Amazon)

The Reason for the Stink, and How to Grow Your Own

• Why does garlic stink? Because it's a defense mechanism.  It's not only people who experience garlic's pungent smell when breaking into it -- animals and insects do, too.

• In fact, the sink factor in garlic is considered to be the plant's own built-in pesticide.

• In double fact, pesticide manufacturers have sometimes used garlic in their products to repel bugs.

• Because it naturally repels many bugs, it's relatively easy to grow.  

• Garlic is also frost-tolerant.  It produces best results if you plant it in the fall and it's in the ground a few weeks before the first frost.

• It reproduces asexually, which means you don't need to start the plant from seeds.  You can pop a garlic clove in the ground, papery husk & all, and it will grow into a plant.

• However, you probably don't want to plant the cloves from bulbs you get at the grocery store.  Those bulbs were most likely grown in some other part of the country, and there are enough varieties of garlic that you can buy a bulb that is best suited to your climate.

• Garlic is such a not-fussy plant, it PREFERS to grow outside.  It won't do well if you plant it in a container indoors because it likes all the vagaries of sun and rain and temperature.  If you've got an apartment, stick a clove in a pot with dirt and put it on your balcony.  Give it some straw for mulch and water it now and then and in the spring, you'll have your very own garlic plant.

If you're going to plant several cloves, make sure they are well-spaced apart like this.  If you're planting in open ground, you may also want to keep track of where you've planted them because garlic has a tendency to split off new cloves and start new shoots where you least expect them.  These tend to grow up smaller and with less flavor, though.
(Photo from 99 Roots)



Garden Betty says when your garlic plants look like this, it's time to dig up those bulbs.
(Photo from Garden Betty)

• Harvest when about half of the leaves turn yellow and start to droop.

• After you pull up the bulbs, brush off the soil and put them in a well-aired shady place for 2 weeks.  The outer husk will dry and turn papery.  This is called "curing" the garlic.  Now you can store the bulbs in a cool, dry place for several months and they won't go bad.

• The only thing that garlic plants don't like are various forms of fungus, mildew, or rot.  If you get fungus on your bulbs (not a pleasant thing), it's probably also in your soil, and it will contaminate your next crop too.  Plant something else in that place for a few rotations and monitor your soil's pH.  If necessary, don't plant anything in the soil and give the sun a chance to blast the bad things out of there for about 4-6 weeks.

• Some scientists think that garlic may be the first plant cultivated by humans.  That's how long it's been around.  That's how much we like it, that for all this time, we've kept growing it and kept eating it.

From Stinky to Delicious?

• Most of the time, we tend to avoid eating foods that smell bad to us.  So why, when it comes to this plant that smells so bad, do we love to eat it?

• Answer: just as cutting garlic changes its chemical composition, so also does cooking.  In other words, cooking it makes it taste a million times better than it smells.

• As garlic is cooked, various compounds in it break down into different aromatics (the smell improves).  The heat also breaks down the more complex sugars and carbohydrates into simpler sugars like glucose and fructose, which we always love to eat.

• In short, cooking it makes it get sweeter and smell better.

• But it still retains some of that savory flavor.  Think of how roasted-in-the-bulb garlic tastes, smeared over crusty bread with olive oil.  There's definitely some sweetness there, but there's also a funky roasted flavor that you just can't get with anything else.

• The thing is, the amount of heat, or the length of time that you heat garlic can yield very different results in terms of flavor.  Cook it only a short amount of time, and it keeps its pungent, sharp flavor.  Sear it at too high a heat or cook it for too long, and it will pass that lovely savory place and enter into the burned, acrid, almost sour place.

• Actually, there are all sorts of factors that affect the flavor of garlic.  Here are some of them:

• Don't smash it -- peel off the papery skin, but put the garlic in the food whole. Some of the garlic flavor will come through, but it will be mild.  Because you haven't released very many of those stinky sulfur compounds, you won't have that pungent aroma to overcome.  But then again, those flavors won't be there to turn into a bevy of delicious flavors, either.  No pain no gain.

• Cut the clove into a few pieces and rinse it first -- the water will wash away some of the sulfurous compounds.  This is especially recommended if you're using fresh, raw garlic in something like salsa or a dip.  Rinsing it first will keep the sulfur scents to a minimum, and since those compounds also tend to get more potent with time, you'll want to add the garlic shortly before serving.

• Use a milder variety of garlic -- the plain white garlic has the strongest flavor.  Garlic bulbs that have a purplish tinge (these are Italian or Mexican varieties) have a milder flavor.  Elephant garlic, which isn't even really garlic and which is the size of a small grapefruit, is white but it has the mildest flavor of all.

These are just some of the different varieties of garlic.  In general, the whiter the papery outside, the stronger the garlic.  Purple garlics are milder.
(Photo from Penny Woodward) 

• Roast it -- roasting the garlic slowly will soften the pungent notes and let the more buttery, savory flavors develop.  The best way to do this is to take a whole bulb, lop off the pointy ends so that the innards are exposed, but the whole thing is still encased in its papery coatings. Cover it liberally with your favorite olive oil, wrap it all up in foil, and put it in a preheated 400º F oven for about 35 to 40 minutes.  When it's nicely softened, you'll be able to squeeze the now gooshy cloves out of the bulb and use it like a spread. Yum.

This is what your roasted garlic should look like when it's done. Like a little honeycomb of softened brown and squooshy goodness.
(Photo from Second Helpings)

• Marinate with it -- this is going toward the less mild, slightly stronger flavor.  If you put cloves (diced or undiced as you prefer) in a marinade with salt or some kind of salty liquid like soy sauce, the salt will draw some of the flavor out of the garlic.  Once you cook your marinated whatever, that garlic flavor will tone down a bit, but some of those raw garlic compounds will be in your marinated whatever.

• Infuse with it -- by this I mean your oil.  Usually people put cloves of garlic into olive oil, but you could do it with whatever your favorite oil happens to be. Some people put the cloves in the bottle of oil and keep it that way.  Be careful not to keep this more than a week or two because it is possible for botulism to develop.  A safer way of infusing is to sauté some garlic in your oil, heat it up and get those flavors going, then toss out the garlic and use the oil to cook the rest of your dish.  You'll have the flavor of developed garlic, but you won't have any actual garlic pieces to bite into.

• If you want a whole lot of that bright garlic flavor, purée it and sauté it -- Pureeing the garlic is doing the most damage to those garlic cells as possible, and thus creating the greatest amount of those sulfur compounds as possible.  Sautéing it cooks away some of the sharpness but also allows some of the savory notes to develop.  Be careful not to let your pan get to hot or to allow your garlic to sit in one place very long or it will start to turn brown/burn/taste bad.

Health Benefits?

• A lot of people maintain that garlic can do everything from being an aphrodisiac to fighting off influenza to curing cancer.

• Researchers are still studying the effects of garlic in rigorous, controlled studies, so they can't say much definitively at the moment.  

• But they have noticed that people who tend to have quite a bit of garlic in their diets tend to have lower rates of certain types of cancer: mouth and throat, stomach, kidney, colorectal, and prostate.  Other types of cancer such as breast, ovarian, bladder, lung, etc., they're not sure whether garlic plays any role or not.

• Some studies suggest that garlic prohibits the formation of blood clots, so that makes people say it would be helpful in preventing embolisms or strokes or heart disease.  But that also means that if you're taking some type of blood thinner, you may not want to eat a lot of garlic, because it might overdo the blood thinning.  Again, this is all still very guessy.

• Other people say it has anti-inflammatory properties and so therefore it might be beneficial to people with rheumatoid arthritis.  Again, a few very small studies have been conducted with some positive results, but it's not enough to make any sweeping, definitive generalizations.

• A few studies have shown that garlic supplements do have an effect on cold & flu viruses.  They do not reduce the incidence -- that is, garlic won't keep you from getting a cold or flu, but it does seem to reduce the amount of time people are sick.  So if you get a cold or the flu, you might try putting some garlic in your chicken noodle soup.  Might make the ickies go away faster. 

This roasted garlic & shallot soup might be just the thing if you've got a cold.
(Photo and recipe available from Once Upon a Cutting Board)

• Garlic also seems to interfere with anaesthesia.  So if you're going to have surgery -- well, they tell you to fast for 12 hours beforehand anyway -- or if you're going to have some sort of dental procedure, you may want to avoid eating garlic ahead of time.  I would guess, since some of those compounds can stay in your system for 2 days, that you might want to avoid garlic for up to 2 days before such a procedure.

• Again, this is all pretty speculative at this point, I am not a doctor, consult your physician for any definitive advice tailored to your specific situation.

Summation

• Let me list all the properties of garlic I've covered here, to show you what I mean:

• stinks but only when necessary
• changes flavor dramatically when cooked
• can be manipulated to produce a variety of flavors
• contains its own pesticide
• frost-resistant
• easy to grow in many climates
• may generate additional sprouts all on its own
• may be anti-inflammatory
• may have anti-clotting properties
• interferes with anaesthesia
• may reduce the severity of colds & flu
• may help prevent cancer

• Pretty cool, huh?

Garlic has about as many properties are there are garlic bulbs in this photo.
(Photo from Care2)


Sources
The Herb Society of America, Garlic, 2004, 2006
Penn State Extension, Garlic Production
Integrated Taxonomic Information System, Allium L.
Compound Interest, What Compounds Cause Garlic Breath? May 5, 2014
Maanvi Singh, Science of Stink: Blame Sulfur Compounds for Your Garlic Breath, NPR, June 21, 2014
Harold McGee, The Chemical Weapons of Onion and Garlic, The New York Times, June 8, 2010 
Healthy Fellow, Garlic Breath Remedies, December 7, 2010
Melissa Clark, "A Garlic Festival Without a Single Clove," [how to use scapes in cooking] The New York Times, June 18, 2008
Rickertville Farm, How to Grow Garlic
The Old Farmer's Almanac, Garlic
Organic Gardening, Disease Defense
J. Kenji López-Alt, Ask The Food Lab: On Developing Garlic Flavor, Serious Eats, January 24, 2013
Food Network, Food Encyclopedia, Garlic
American Cancer Society, Garlic
South Beach Diet, Get the Most from Garlic
Nantz M P et al., Supplementation with aged garlic extract improves both NK and γδ-T cell function [. . .] Clin. Nutr, June 2012
Denisov L N et al., Garlic effectiveness in rheumatoid arthritis, Ter Arkh, abstract, 1999