I get emails often from readers who have tried this recipe or that, or many of them and have had fantastic results and they just want to tell me about it.

And I love hearing from my readers, especially when they are happy with the recipes they have tried, but you know, I am just as happy to hear from folks who have questions, or who don’t understand something about a technique, or, heaven forbid, one of my recipes goes seriously awry. I haven’t often gotten any of the last emails, but I did get one a day or so ago, and I wanted to share what I said to the reader, because I think that while I have addressed this issue in the past, it was in the middle of a post, and there was no way for anyone to find it after this.

The issue is the use of yogurt in Indian cookery, and why I almost always specify full fat or two percent yogurt rather than lower-fat or non-fat yogurt in my recipes.

The thing about yogurt is this–if you use full-fat or two-percent yogurt, it is less likely to separate and curdle when you use it in cooking Indian curries. In fact, when I have used whole milk Greek yogurt (the brand I can get consistently here in Athens is Fage), in curries where the yogurt is part of a marinade that is then cooked for the full time on the stove at a simmer or boil, or where the yogurt is added halfway through cooking in order to cook into the sauce, I have never, ever had it curdle and turn a silky sauce into a glumpy mess. Never.Even when I have cooked it in a pressure cooker, which means it is hotter than boiling.

Whole milk regular yogurt, which is not strained generally does not cause any problems. The regular whole milk yogurt brands I like, in order of preference are Brown Cow, Seven Stars and Stonyfield Farm and they all work admirably in curries, though I have found that because they have the thin liquid–the whey–which is mostly water–still intact, they take longer to reduce into a good, thick, clingy sauce. That is why I have switched to using Greek style, strained yogurt exclusively in my Indian cookery.

Why do lower-fat yogurts curdle or separate when they are simmered or boiled?

The problem is the ratio of protein to fat in them. The fats in whole milk, cream and whole milk yogurt surround the proteins in dairy products, and create a buffer between the protein and the heat. (I am vastly simplifying here…but bear with me.) Protein chains, which in their uncooked state are smooth, will knot up and become firm when they are heated–that is why raw and rare meat are softer than well-done, fully cooked meat. If there isn’t sufficient fat mixed in with the milk proteins in yogurt or milk, when it is heated, the proteins will knot up and separate from what fat is there and the whey, causing a sauce to “break” or “curdle.” (This is the same way you can make cheese, by the way–you can heat skimmed milk, or you can add an acidic agent, such as vinegar or lemon juice, which will also cause the proteins to firm up, or you can add rennet, an enzyme, which will do the same thing–firm up and separate the protein molecules from the whey.)

But here then is the problem–what if all you have in your fridge is low-fat yogurt and low fat milk, as happened with the reader who wrote to me about her bad experience in making Safaid Keema Mattar?

Are you doomed to have a beautiful dish with a creamy sauce one second, only to turn your back to get a couple of plates then see a curdled mess where your delicious curry had been only a few seconds before?

No. There are ways around it.

One thing you can do, if you only have low fat or fat free yogurt in your fridge, but you want to make one of my recipes, is check and see if you have any cream in your fridge, too. If you do, you can whisk a few tablespoons of cream into your yogurt before using it, and then cooking it gently on lower heat than I specified in my recipe, for a slightly shorter amount of time–and you should end up with a delicious, smooth creamy sauce.

What if you don’t want to use high fat dairy items like cream or whole milk or whole milk yogurt in the first place? Are you still screwed?

No.

Here’s what you do–you still use your lower-fat dairy products, but you modify the way in which I specify the dairy products to be used in the recipe.

If you use only low-fat or fat free yogurt in a cooked curry, add the yogurt, preferably Greek, or if you use regular yogurt, strain it before you use it–at the very end of cooking. And when you add it, only use 3/4 of the amount listed directly in the sauce. Set aside the remaining 1/4 of the yogurt to be added later.

So here are the steps you need to take to successfully use lower fat yogurt in your curries–whisk your Greek or regular strained yogurt thoroughly before mixing it into the curry. Measure out 3/4 of the amount specified, and when the rest of the curry is cooked, turn off the heat and stir this amount of whisked yogurt into the curry. As soon as it is incorporated and the sauce has warmed itself through residual heat, whisk in the remaining amount to cool the curry further and remove the pan from the stove and serve the curry immediately.

You see, you are not cooking the low-fat or non-fat yogurt at all, which is why I specify that you use Greek or strained regular yogurt for this method. Since you cannot simmer or boil this sauce to reduce the whey and water in it in order to thicken it and concentrate the flavors, you must remove the whey in some other method, and that method is straining it! The Greek yogurt is already strained, which saves you the trouble of doing it, but you can strain your regular yogurt the night before by lining a sieve with cheesecloth and dumping the yogurt into it, then twisting the cheesecloth around it tightly and setting the sieve over a container to catch the whey. If you do this, don’t throw the whey out–you can use it in cooking–you can use it as the liquid in breads, you can use it cooking vegetables and grains, and you can add it to soups or vegetable broths–so long as you are not cooking vegan vegetable broth, of course!

If you must cook the yogurt somewhat and you are not using whole milk yogurt, proceed cautiously and only cook 3/4 of it in the sauce, on a very low simmer, stirring the entire time. If it starts to look suspiciously like it is going to curdle, turn off the heat, move the pan away from the hot burner and stir in the reserved amount of yogurt to cool the curry in order to prevent the incipient curdling action.

If you are using yogurt in an uncooked Indian preparation, such as raita, it doesn’t matter if it is fat free or whole milk–it will not change the texture unduly to use the fat free or low fat product at all.

I hope that this post clears up some of the issues surrounding the use of yogurt in Indian curries and why I often specify whole milk yogurt rather than non-fat or low fat.

Once again–you -can- use lower fat dairy products in Indian cookery and often that is desirable, but you must treat them carefully and heat them slowly, and gently, because they are just not as stable as the full-fat versions.

Some fresh foods can simply be converted to frozen foods without much work or trouble, and then, can be used from the freezer over the course of months, instead of days. Sweet and hot peppers can both be simply chopped or sliced, packed in plastic bags and frozen. The same can be done with onions and garlic. Spinach can also be frozen with minimal processing–if the leaves are mature, remove the thick veins and stems and either leave the leaves whole or tear into smaller pieces and then pack into bags and freeze. If you have baby spinach, you just pack the whole leaves into bags and freeze them. Frozen spinach leaves can then be added directly to simmering soups, stews or sauces without pre-cooking.

Fresh herbs can also be frozen with minimal preparation. Most of them can just be chopped finely and frozen in bags, although some people put tablespoon amounts into individual compartments in an ice cube tray, and add a little bit of water to hold them together, then freeze the cubes. After they are frozen, the cubes can be packed in plastic bags and stored for future use. Some herbs, like cilantro and basil, can be pureed and then frozen in ice cube trays without the addition of water, and can be used like the chopped frozen herb cubes.

Alternately, batches of green cilantro chutney or pesto can be made and frozen, either in small bags or containers, or in cubes, to be thawed and used later or to be added to curries, soups and sauces as they cook.

Fresh fruits such as strawberries, blueberries, raspberries, blackberries and mangoes can all be frozen simply as well: for the berries, you just wash and dry them, then layer them onto sheet pans, put them in the fridge until they are frozen, then pack them into bags, label and date them and store them in freezer. Strawberries can either be frozen whole or sliced. All of these fruits can be used to make pies, dessert sauces, ice creams, sorbets and smoothies in the future.

For mangoes, simply peel and pit them, and cut into slices. Treat with a bit of lemon juice to prevent discoloration, and freeze on sheet pans and then pack into bags. I like to use frozen mango to make lassi, chutneys, salsas and to add to curries.

Tomatoes can be frozen whole, but they are better, and they take up less space, if you make them into a nice marinara sauce or plain tomato sauce, pack these sauces into quart bags and freeze them flat, so they stack easily in the freezer for storage. (Speaking of tomatoes, you can also use the freezer to store excess tomato paste. Restaurant pack tomato paste is often sold in huge units of several quarts or pounds. If you don’t need that much in whatever recipe you are using, the rest can be stored in smaller portions from a cup to a tablespoon in freezer bags. For the smaller amounts, you can squeeze the paste into ice cube trays or freeze tablespoon-sized plops on a sheet pan lined with waxed paper. Once they are frozen, the cubes can be popped into a bag, or the plops can be peeled up and popped into a bag which then lives happily in the freezer until it is needed. You don’t even have to thaw the paste before using it, although I always do.)

Speaking of sauces, we come to the issue of stocks, soups, sauces and stews.

These types of recipes are the secret weapon of cooks and chefs when it comes to using up excess ingredients.

If you have some potatoes on hand that have gone a bit soft, or some carrots that are a little rubbery, or some celery that is no longer crisp, then don’t throw them out–use them in a soup or stew or a sauce. Daily soup or dinner specials are not just a way to vary a menu, they also help a chef or cook deal with surplus perishable ingredients in a delicious and constructive fashion.

I don’t feel in the least bit bad about using slighly older produce in soups or stews, because it isn’t like I am using rotted food. Far from it–slightly older vegetables which would be nasty in a stir fry or salad are perfectly fine to be boiled in a soup or stew where the liquid is meant to be eaten along with the vegetables. With vegetables that are a bit too old, often the only characteristic that suffers is texture, and with a soup , stew or sauce, that doesn’t matter. The boiling water extracts all of the water soluble vitamins left in the vegetable, and then they are eaten in the broth, along with the solids. The flavors are all extracted and present in the finished dish, and frankly, there is nothing more homey and comforting than a stew or soup.

Stocks are a special case. Stocks are made, in large part, from parts of animals and plants which are frankly, otherwise inedible to people. Bones are not a big part of the human diet when they are whole, but when they have had all of their goodness extracted by a long simmer in a stockpot, they create the basis for every great soup, sauce and stew–stock.

Every chef I have ever known has extolled the virtues of the stockpot, not only for creating kitchen gold, but also because it fits perfectly with their frugal natures. Bones cannot be eaten by people, but there is no need to throw them away without first extracting every ounce of goodness from them. Carrot ends, celery leaves and ends, leek tops and onion skins also are not palatable to humans, but they add flavor, fragrance and color to stock. (Onion skins give a golden color to chicken stock which makes it more appealing to the eyes.) Bones from every animal, along with fish heads and tails, shrimp, crab and lobster shells, and crustacean heads, are all saved by chefs and used to make stocks which results in every scrap of food being used to make a food product that only enhances every other dish to which it is added. Stocks can be frozen, too, in whatever increments one likes, so they can have a very long shelf life, although in larger restaurants, a stockpot or two are always going on a back burner of the stove and what it makes is used up as it is made.

Stocks are simple, and make goodness out of what many people would see as garbage, using bones, vegetable scraps, herbs (and yes, you can use some herbs that are not pretty enough to put on a plate as garnish, but are still good to cook with in a stock, and unlikely bits of carcass like chicken or pig’s feet. (For illustrated instructions on how to make chicken stock, click here. For Chinese style pork and chicken stock, click here.)

Running a restaurant does not have to be a wasteful enterprise. In fact, if the chef is clever, it can be the exact opposite–it can be a model of how best to use every scrap of edible foodstuff inherent to any given ingredient, but it does take a little extra work to avoid just throwing away raw materials.

The next post will talk about what happens to food that is already cooked in a restaurant, and how to avoid throwing it away.

I had a reader ask me last week how I manage to cut my onions thin enough so they brown easily and completely for the proper Indian flavor. I tried to explain it completely with words, but I thought that it would be much easier to do an in-depth post with photographs to explain not only the process of cutting, but also browning the onions. I have found over years of teaching Indian cookery that many American cooks will stop cooking the onions much sooner than they should–they fear burning the onions so much that they will not cook them long enough.

So, when I teach Indian cookery in a classroom situation, I always emphasize the process I am showing here, and have the students all watch and participate in each step.

As you see from the photograph above, everything starts with cutting off both the root and top of the onions off.

Then, set the onion on one of the flat ends formed when the root or stem is cut off, and cut straight through the center of the onion.

Peel off the first layer of the onion along with the onion skin, and discard it.

Then set the onion halves down on the large flat cut side. It will be very stable this way.

I use the sharpest knife I have to cut onions, and I like to use one with a hollow-ground edge, because the tiny divets created by this grind helps keep the very thin slices from sticking to the knife blade. Some people like to use smaller, short-bladed knives for slicing onions, but I prefer my seven-inch long santoku knife–that is a Japanese knife that is usually used for precision cutting vegetables, tofu, fruits, mushrooms, and boneless meats.

To hold the onion, tuck your fingertips under your knuckles as shown, and starting slowly, cut a very thin slice off the end of the onion. Cutting in the proper way, you will see each slice made of thin half-rings of onion. I find that if you saw back and forth slowly with the part of the blade closest to the handle, for the first part of the cut, you can stabilize the onion, and then continue the cut by pushing forward with the knife, then drawing the knife toward you while pushing down. This is called a “draw cut” and it is the easiest, and safest way to get a thin slice of a firm vegetable like an onion. With practice, you can make paper-thin slices of onion that you can see through with this method.

Continue cutting in this way as far as you can safely do so. The last half-inch or so of the onion is impossible to safely keep steady upright on the cutting board, so you lay it down flat. This way, it is steadier on the board, and you can cut it into very thin slices as well.

It doesn’t matter at all that these final slices will be in a different shape than the first slices, because the onions will cook down completely, and the shapes will be unrecognizable. So, do not worry overmuch with the shape of these last slices, just try to make them the same basic thickness as your first slices.

Continue cutting until you have the amount of onions you need for the recipe you are working on.

Before we continue on to the process of cooking the onions, I want to talk a bit about choosing onions for Indian cookery. Unless some other onion is specified in the recipe, plain old yellow onions are the best choice for Indan food. Why is this?

It has to do with the fact that they have the least amount of water in them of any other type of onion you can find in the typical American supermarket. Low moisture content is perfect for browning onions quickly and evenly, because the first step of the caramelizing process is to rid the onions of excessive water. This step also takes the longest time to accomplish. (I have been told by my friends from India, Pakistan and Bangladesh that the onions in the US are much waterier than the ones in their country, and so they take longer to cook down to a proper deep brown color and flavor.)

Whatever you do, resist the urge to use Vidalia, Walla Walla or Maui sweet onions, because these have even more liquid in them than the standard grocery store varieties. Save these to use as raw relishes or in uncooked chutneys and as garnishes for seekh kebab or grilled chicken where their sweet flavor and crisp, juicy texture will shine.

Now we come to the type of pan to use.

Whatever you do, don’t use a pan with a nonstick surface. Nonstick coatings interfere with the proper development of the darkened sugar residue that coats the bottom of the pan while the onions cook. You want the sugar from the onions that is leeched out of them with the water which boils off as the onions cook, to stick to the pan and turn brown. So, whatever you do, don’t use nonstick pans for your Indian food.

Secondly, use a heavy-bottomed pan which heats evenly. Thin-bottomed pans will heat up quickly, but they also tend to form hot spots on their bottom surfaces, which will lead to the sugars not only sticking, but burning. And this can happen within a matter of seconds.

My favorite pans to use for cooking onions this way are the enameled cast iron braising pans from Le Creuset. But, if you don’t have any such pans and can’t afford to get one, invest in a plain old Lodge cast iron skillet and cook in that. Not only will you make luscious caramelized onions and Indian food with authentic,deep flavor, you will also be adding iron to your food. Besides, such a pan will last several lifetimes of curry-making–you can pass it down to your grandkids, along with the secret for making perfectly browned onions.

The cooking medium you use for browning your onions is up to you, but I prefer to cook mine in ghee, butter or canola oil, depending upon the recipe, my mood and what is in the pantry at the moment. Just be certain to use a little bit more oil than you think you need, because while you want the sugars left behind by the evaporating water to stick to the pan and brown, you don’t want the onions themselves to stick and burn.

Heat the pan with the ghee, butter or oil, over medium heat until it is quite warm. Add the onions, and spread them out into an even layer covering the bottom of the pan with a flat-edged scraping tool, like a spatula. I like my bamboo spatulas for this job–they are inexpensive, sturdy, beautiful and durable–I throw them in the dishwasher, and they last for years. Try doing that with a hardwood utensil, and you will regret it!

Then, sprinkle the onions with a teaspoon or two of salt. Sprinkle it evenly over the top of the onions, and then give them a nice rough stir. This not only distributes the salt, but it also breaks up the onion slices–you don’t want them sticking together, but instead you want theindividual bits to separate, thus exposing the maximum surface area to the hot pan and oil as possible.

The salt not only seasons the onions, but also helps draw the water out of their tissues more quickly. You -can- do without it if you are dedicated to a low salt diet, though the process will take a little bit longer.

After you have stirred the onions the first time, leave them undisturbed for a few minutes, or just until some onions along the edges of the pan show a hint of color and you can smell the onions beginning to brown. At this point, stir the onions, and keep stirring. Stir, and stir, and stir, until you feel like your arm is going to fall off and your mind is going to go numb from boredom. And then, stir some more, because this is the key to getting the onions to release their water quickly and evenly, and it is essential to cooking your onions without burning them.

(Here is where I am going to make a confession. I have been cooking onions to a deep brown for so long, I usually do it without stirring them constantly. I can stir them, then go off and cut some other ingredient or parboil something or peel something, then go back and stir just in the nick of time, then walk away, and come back, just before they burn. This is because I can listen to the sounds of the onions cooking and smell the depth of browning without looking. This has taken me years of practice, and I do not suggest that beginners try to do my “Zen method” of onion cooking until they have gotten really good at the “Stir Until Your arm Falls Off” method. I will say that developing the senses necessary to do the Zen method of onion browning does allow for much more multi-tasking in the kitchen, which is invaluable, especially at work.)

What you will see happeniing is your onions will go limp first. They wilt. Then, you will see juices bubbling out of them, and they start to turn translucent. Then, they turn golden, and this is where a lot of Americans want to stop cooking and call the onions done. Nope, Kemo Sabe, you are not even halfway finished. Keep cooking those onions, and you will see them start to turn to a nice, rich, good-smelling medium brown color that looks an awful lot like the photograph you see here.

See all of that reddish brown stuff stuck to the bottom of the pan, particularly in the lower-right hand corner of the photo? Well, those are those sugars I was talking about. What you want to do is get them off the bottom of the pan and integrated back into your onions, because that layer of browned sugars is filled with flavor. And, color.

There are two ways to get those sugars off the pan and back into your onions. One is the logical but sometimes more difficult method, and the other is the completely counter-intuitive but easier method.

The first, slightly more difficult way is to use the remaining liquid in onions themselves, to “deglaze” your pan. That means you gather up all of your onions, and slide them forcefully over the browned areas of the pan, scraping at the browned bits with your scraper/spatula. Sometimes, this works great, and the onions will pick up the color of the sugars, and the pan will scrape almost perfectly clean with a minimum of effort. Other times, the sugars will stick stubbornly, and all that will happen is you will get a sore wrist from all of that scraping;.

Which leads us to the counter-intuitive method. Add a little bit of water to the pan, and deglaze it like normal, by scraping up the browned bits, which dissolve into the water, and then, as the water is boiled away, is transferred to the onions.

I know you think I am nuts–didn’t I just say that the point was to remove as much water from the onions as possible? So why add more water?

What I have found is that in some cases, adding a tiny bit of water–about a quarter cup or so–to a pan of onions at the point where the onions have just started to turn reddish brown, and the sugars are clinging stubbornly to the bottom of the pan and are starting to edge toward bitter black rather than savory brown, adding water actually helps cook the onions faster. Too much stuff stuck to the bottom of the pan keeps the onions from continuing to cook, as it makes a buffer to the heat–dissolving that into water keeps the pan hotter, and helps the onions cook. And, for whatever reason, once dissolved from the pan bottom, the onions will cling to the onions as this added water evaporates, instead of once again sticking to the pan. Why this happens, I cannot say, but it does.

Whichever method you use to get those sugars off the pan and back onto your onions, do it, and keep stirring, until your onions are finally cooked down to an almost jam-like consistency, and are a rich, mahogany color–reddish brown. The color I wish my hair was naturally.

So, there we are. Deeply browned, caramelized onions. Why are they so damned great and what do you do with them once you have them?

First of all–they taste amazingly good, and without them, most Indian dishes that are supposed to contain onions, taste sort of weak and shallow. Browned onions are the bottom note, the basis of a curry, the starting point. They are the foundation, and without them, a curry can just seem one-dimensional. They add sweetness and an indefinable “brown taste,” and they completely lack any harshness. They also add color to many curries–a nice dark, reddish brown that is appealing to the eye, as well as to the tongue.

After they are cooked, you can leave them as they are, or grind them up into a puree. It depends on what texture you want your sauce to have–if you don’t mind it being somewhat chunky, leave the onions alone, but if you want it to be velvety smooth with no discernible lumps, puree the onions before adding them back to the pan with other aromatics, such as garlic and ginger, and spices.

So that is it. A primer on how to cut and cook onions properly for delectable Indian food.

I’ve been reading articles about the health benefits of curry spices for quite some time, but this article from AlterNet is particularly good because it brings together summaries of the latest research on a variety of spices.

Worldwide, a great many researchers are finding that spices commonly consumed in Indian curry dishes have myriad health benefits, corroborating the uses of these spices in Ayurvedic and other food, herb, and spice based medical traditions. While these findings are preliminary, all of the studies cited in the article have been published in respected peer-reviewed journals, so that other researchers can verify or refute the findings through their own studies.

Here’s a short run-down of some of these findings:

Cinnamon has been found, in relatively small doses (but still more than you would use in a curry or muffin), to lower blood sugar levels in adults with type II diabetes. The same study that reported this finding also noted that cinnamon reduces blood cholesterol levels. The dosage used to gain these effects in the study participants was just a half teaspoon daily.

Turmeric, the spice which gives many curries their vibrant yellow color, has been used as a remedy for a wide number of ailments all over Asia for centuries. Recently, scientists have found that it may help keep Alzheimer’s at bay–patients who ate curry frequently, or even occasionally, were noted to have significantly fewer protein plaques in their brains. Mice fed a diet with turmeric were found to have 80 percent fewer protein plaques in their brains, and it was noted that curcumin, the active compound in turmeric, also reduced inflammation and cell oxidization. It has been found that the people of India have the lowest rate of Alzheimer’s in the world; currently research is being done to determine if this is caused by genetic factors or if it has to do with the large amounts of turmeric consumed in the typical Indian diet.

Turmeric is also being investigated for its cancer-fighting potential. Apparently, it has been found to help block the growth of cancer cells while not harming normal cells.

One thing to remember: curcumin is not water-soluble, so it is necessary to cook it in oil of some sort to gain its benefits. Do as the Indians do and cook it in ghee or oil before making a curry in order to extract the helpful curcumin, in addition to getting all the flavor and color of the spice into your food.

Chili peppers not only have their widely known antiseptic properties, but have also been found to have the ability to shrink tumors and inhibit the growth of cancer cells. Capsaicin, which has been used to relieve the pain of arthritis when used externally, also may have the potential to help fight obesity when taken internally by boosting the metabolism.

Ginger has been a popular folk remedy for nausea, particularly morning sickness for generations, but finally, it has been proven that the effect is not related to mind-over-matter or a placebo effect. In addition, this relative of turmeric is also being found to have the potential to lower blood sugar, cholesterol and to protect the stomach from ulcers. It also has anti-inflammatory properties which would make it valuable in fighting the pain and swelling of arthritis.

Generally, I eat curry because I love the many flavors, textures and colors inherent to this broad spectrum of dishes. But, I have to admit that I am even more keen to eat it now that I see that the Indian assertions that curry is healthy are not just based on tradition, but sound scientific research as well.

And, I have to also admit that I am very happy to see Ayurvedic traditions being proven through the application of the scientific method. It just goes to show that just because a medical system is ancient, doesn’t mean that it is just folklore or old wive’s tales. Many ancient medical traditions are based just as much on experimentation and observation as modern allopathic medicine.

So, do as I do, and eat a lot of curried dishes, not only for pleasure, but for your health!

I love the roseate slices draped over nigiri, enrobing the rice and vinegar balls with their delicate flavor and buttery rich texture.

Even more, I love the sensual process of eating tuna sashimi, plucking each slice like the petal of a fleshy blossom, dipping it lightly in wasabi-kissed soy and popping them in my mouth. Sweet, salty, a little hot, definitely sexy.

And I am not the only one. Nearly every one loves tuna.

But, it looks like we may have to moderate our love a little bit in order to keep from poisoning ourselves, our unborn offspring and our nursing babies.

Yesterday, the New York Times published an article where tuna sushi was bought at several Manhattan outlets, both restaurants and stores, and all were found to have elevated amounts of mercury in the flesh of the fish, in some cases, amounts significantly higher than what is considered safe by the EPA.

In fact, some samples of the fish had mercury levels high enough that the FDA could have had them removed from the market. (Of course, the FDA did not take action.)

This is not just bad news for New York sushi lovers, but for everyone who loves tuna.

Because if the fish sold in New York City is contaminated, it is a good bet that the fish sold all across the country, indeed, the world, is contaminated.

Why?

Because it is the way that mercury works in the food chain that is in play here.

Tuna are top-level predators in the ocean; they are at the top of their food chain. Mercury is ingested first, by the plankton and becomes part of their body tissues, then the plankton are ingested by shrimp or other small crustaceans or fish, and then those animals are eaten by larger ones, so on and so on, until we get to the massive tuna, who eat the largest fish.

Each time mercury is eaten, whether directly, as in the case of the plankton, or indirectly, as in the case of the fish who eats the plankton, it settles in the tissues of the animal who eats it. Each time it moves up the food chain, the mercury level rises–it essentially concentrates as it is passed from fish to fish . By the time we get to the tuna, a very large, voracious predator fish–the levels of methyl mercury in its flesh are quite high–in many cases, high enough to be unsafe for children, and pregnant or nursing mothers to safely eat.

What is sad is that this is not a new problem–it has been known for years that tuna is only moderately safe to eat. In 2004, the EPA issued a report warning pregnant and nursing mothers to eat only moderate amounts of certain kinds of seafood, including fresh tuna. It is probably that the EPA/FDA is going to revisit those guidelines and adjust them sometime in the coming year to reflect new data.

A similar study of sushi tuna in Chicago from 2006 also resulted in findings of higher than safe levels of methyl mercury in the fish, similar to the findings of this month’s New York survey. The Chicago survey, however, used a larger number of samples, which, again, points to a larger problem than most people might realize.

In July of last year, one quarter of New Yorkers were found to have elevated mercury levels, primarily from eating fish. The people with the highest amount of mercury in their bloodstream in this survey of New Yorkers were Asians, women and those with higher income levels.

So, what is the big deal about mercury anyway–what is it going to do to us?

For most adults, these levels of mercury are not that problematic, but for women who are of childbearing age, who may be pregnant or nursing, the dangers to their children are sobering.

In a developing fetus, or a breastfeeding infant, mercury can cause neurological and brain deformities, severe physical deformities and can wreak havoc on many developing organ systems. The danger is great for young children, too–so long as a child’s brain and nervous system are developing, mercury can cause significant damage.

((For a more in-depth article on mercury in fish, and its implications for children and women, see my older post here.)

What is the upshot of all of this?

First of all, I think that the FDA and EPA should revisit their guidelines for safe consumption of tuna, particularly in regards to women of childbearing age and children.

And secondly, I think that we need better regulation on the amount of mercury that is allowed to be dumped into our atmosphere by industry; pollution is the major source of the mercury which eventually ends up in blue fin tuna on our plates in sushi restaurants.

Thirdly, perhaps we should be more careful about testing mercury levels in fish before it goes to the marketplace.

Of course, all of this requires money from the government to fund these enterprises, and since these regulations would go against the interests of the fishing industry and various manufacturing, chemical and coal industries, I doubt that much will be done.

Maybe I am just being cynical about all of this, but I don’t really think so–just look at the FDA’s track record on the issue of food safety in the beef industry.

Why should the fish industry be any different?