Coming Soon: Sous-Vide and Low-Temp Primer

posted by Dave Arnold

We are feverishly working on our Sous-vide and Low-temperature Cooking Primer. Here’s a little taste of what’s coming, in the form of some fancy charts:

What sous-vide hanger steak looks like at various temperatures.

Salmon cooked at various temperatures. Interesting: fish often go through two zones of goodness: a low temp zone usually described as having a fudge-y texture, and a higher temp zone that makes a more classical texture. Fish cooked between these zones squeaks when you chew it. The exact temperature of the two zones depends on the fish itself, the season in which it was caught, the fat content, etc.

Should I sear before or after?

How much does the internal temperature of my meat rise when I sear? Enjoy.

How long do I need to cook to kill bacteria? Here you go.

What happens to eggs at various temperatures? All eggs were cooked in a water bath for 75 minutes (an hour is enough) at the temperature indicated.

The times and temperatures we use to cook. There is no right and wrong --just what you like.

Pressure Cooked Stock 2: Changing Pressures, Playing with Chemistry

posted by Dave Arnold   

This is our second post on the benefits and pitfalls of pressure cooking stocks. See the first post here.   

We recently bought a fancy new pressure cooker, in which to do fancy new tests. It’s actually a pressure canner/sterilizer—which lets me work with higher volumes and with higher pressures. First we investigated which pressures are best for cooking chicken stock and veal stock.  Second,  we tested to see if we could increase flavor extraction by treating stocks with a strong base. This test was suggested  by our reader Schinderhannes,  and it turned out to be a doozy.  

Our fancy new pressure device, the All American Sterilizer, 25 quart.

A Brief Recap  

The right pressure cookers can make stocks that are superior to traditional stocks.  In our tests, pressure cookers that vent steam while cooking made stocks that were browner and had better aroma than traditional stocks—but they tasted worse, were less balanced, and were more muted than traditional stocks.  Pressure cookers that did NOT vent steam beat conventional stocks by all criteria.  I know, it’s counterintuitive that the vented pressure cooked stocks would have better aroma  but taste worse (wouldn’t the aroma have vented off?), but we verified our results with repeated blind tastings.   

Our Iwatani pressure cooker regulates pressure by venting steam. The gauge on the right is unreliable and cannot be trusted to regulate pressure.

It seems like pressure cooked stock should always beat traditional stock because: 

• There isn’t much turbulence inside a pressure cooker, so cloudiness is reduced.
• Higher extraction temperatures extract flavor more completely.
• Higher temperatures encourage more delicious “high temp flavors,” such as the meaty flavors caused by increased protein breakdown.
• The sealed pressure cooker should preserve volatiles.

Why venting pressure cookers underperform is still a mystery to me.  But they always do.

A Note on our New Pressure Cooker
The Wisconsin Aluminum Foundry Company (WAFCO) has been making the “All American” line of pressure canners since 1930. Their pressure canners are made entirely of aluminum and are usually big (up to 41 quarts). Pressure canners are designed primarily to sterilize jars and cans for home canning—not to cook in. The standard pressure canner regulates pressure with an adjustible weight, so once working pressure is reached, it vents steam—bad. You can make the weight heavier and use the very nice and accurate gauge to regulate pressure up to about 18 or 19 psi without venting, but to really go high-pressure you want a pressure sterilizer. Pressure sterilizers are used by dentists and tattoo artists; they are basically inexpensive autoclaves.  Our WAFCO canner converts to a sterilizer just by changing out the lid.   We have the 25 quart stovetop model.  

Sterilizer Top. The valve on the right can be flipped off and on to vent as desired, but won't leak steam till you hit 25 psi. Be careful. On sterilizers this valve is connected to a long tube inside the pot. If the tube is underwater, pressurized hot liquid will spray everywhere when the lid is vented.

The pressure sterilizer will not vent  steam unless you release the valve or take the unit above 24.5 psi. It is dead quiet. A regular pressure cooker at 15 psi reaches 250° F (121° C). My pressure sterilizer running at 24.5 psi reaches 266° F (130 ° C).   

The All American Sterilizer gauge. This gauge works. Here it is reading 24.5 psi which equals a blistering 266° F (130° C). Any more pressure and the sterilizer auto vents.

The 25 quart pot heats rather slowly, and it takes a while to get the hang of regulating pressure by adjusting the gas—I plan to build a temperature regulator soon. Be careful with the sterilizer. It has a tube on the bottom of the lid. If that tube goes under the surface of your cooking liquid, the vent valve will spray hot liquid when opened. In these tests we cooked our food in stainless bains that we put inside the pressure sterilizer.  

One quirky feature of these pots: they have a  metal-on-metal seal, with no rubber gasket.   

The All American sterilizers and pressure canners use an all-metal gasketless seal.

Test Number 1, Changing Pressures   

We ran this test on previously prepared stocks so we could eliminate ingredient variables.  The tests discussed in our first pressure post indicate that pressure cooking a previously prepared stock produces similar results to creating a stock entirely in the pressure cooker.   We treated white chicken stock and brown veal stock  in five different ways, as follows:   

• Heat briefly on the stove (control 1).
• Pressure cook in a venting pressure cooker at 15 psi for 30 minutes (control 2).
• Pressure cook at 15 psi for 30 minutes.
• Pressure cook at 20 psi for 30 minutes.
• Pressure cook at 24 psi for 30 minutes.


Pressure tasting: Brown veal stock on top, white chicken stock on the bottom. 15 psi non-vented was the winner, followed by regular.

You can see that higher pressures = browner color.  Chicken and veal stocks reacted similarly at the same pressures, so I’ll discuss them together.  Confirming our previous results, stovetop was better than 15 psi vented, but not as good as 15 psi.  The aroma of 15 psi vented was superior to both stovetop and 15 psi unvented—bizzare. 20 psi had a good aroma, some thought better than 15 psi unvented, but its taste was muted.  The 24 psi stock was the brownest by far, but smelled and tasted dead.  We need to run tests between 0 and 15 psi to determine optimum pressure.  

Result:  15 psi non-vented chicken and veal stocks were the winners.  

Test Number 2, Adding Lye:   

This one gets a little weird. Friend of the blog and pro-chemist Schinderhannes suggested that we try to increase the meaty flavor of stocks by disrupting the proteins with a strong base (like sodium hydroxide, also known as lye), pressure cooking them, and neutralizing the base with a strong acid (like hydrochloric acid).   Don’t get freaked out, we aren’t serving this to people—it was just a test.  

There’s something very appealing about Shinderhannes’ proposal.   Lye ( NaOH) + Hydrochloric acid (HCl) combine to make water and table salt (H2O and NaCl).  The trick to not poisoning people is neutralizing the lye.  

We don’t have access to high grade lye, so we used this:  



100% lye drain cleaner. Lye is NaOH. Don't do this at home.

Don’t use this stuff.  I don’t want to hear about you getting hurt. Eating only a small crystal will do severe,  irreparable damage to your insides.  My doctor mom used to tell me horror stories of kids who came into the ER after eating drain cleaner. Anyway, we prepared two identical batches of chicken meat and water, added some 33% lye solution to one (we added 0.5% by weight NaOH to the stock), and pressure cooked them both for 45 minutes in a non-venting pressure cooker at 15 psi.  Here is what they looked like:  



Two pressure-cooked stocks, normal on the left, with added lye on the right.

The difference is pretty plain.  The lye stock is still poisonous at this point so we need to add hydrochloric acid to neutralize it.  Problem is, I can’t get pure hydrochloric acid, so I went to the hardware store for muriatic acid, which is fairly concentrated HCl, used to clean tiles.  We added enough HCl to get a neutral reading on our pH meter.  Look what happened:  



Pouring in acid to neutralize the lye-stock caused a weird precipitation reaction.

Whoa! The stock turned white and clouded up.  I tasted it to make sure it wasn’t poison.  It wasn’t.  Then we figured out how much salt to add to the normal stock to match the salt created in the lye stock acid base reaction.  



Our chemistry set: Muriatic Acid Tile Cleaner (HCl), 100% Lye Drain Cleaner Solution (NaOH). Kosher salt (NaCl), pH Meter, Buffer Solutions.

Here is Nastassia tasting them blind.  



Since the stocks looked very different we tasted with our eyes closed.

Well, the normal stock won.  The lye stock tasted a little weird.  The next day the lye stock looked even stranger:   



After resting overnight, the lye stock (on the right) had a bunch of goop floating in it and smelled of lye.

The stock on day 2 smelled and tasted strongly of lye.  I’m  guessing the lye was trapped in the precipitate that formed when we added the acid, and it leached out overnight.  The lye taste was still present after we got rid of the cloudy stuff in our centrifuge. 

All in all, not a ready-for-prime-time technique, but a fun experiment.

Whole Fish à la Cooking Issues

posted by Dave Arnold

Pretty picture of a fish in oil

Cooking a large whole fish is challenging.  It’s easy to overcook the outside, leave the inside raw, or both. This problem keeps cropping up for me. You see, my stepfather Gerard has three interests: drinking wine, smoking cigars, and  surf casting for striped bass. He’s an accomplished fisherman, and he catches nice big guys –36-40 inches — along the beaches of Cape Cod, whereupon he delivers them to me. When I cook for my family,  I like to cook family style. I want to serve a fish whole, and naturally I want to serve it fried. For years I just bent the suckers into a “U”, dusted them with flour, and chucked them in my deep fryer. They were good, but, truth be told, the outside was overdone and the inside wasn’t really done at all. No one noticed because I served pla pad prik style, with a generous amount of spicy Thai curry.  But Nils and I have worked out a better technique with the miracle of low temperature cooking (low-temp and sous-vide primer soon to come).

Many fish, like salmon and mackerel, don’t hold up well when cooked for a long time at low temperatures.  Their enzymes keep working while the fish is cooking, breaking down the muscle and making it mushy.  The same holds true for crustaceans.  Some of these fish also taste terrible when they’re cooked to safe bacteria-killing termperatures:  Salmon served warm, for example, shouldn’t be cooked much above 50 C for taste, but anything below 50 C is actually growing bacteria. Stripers, however, are made for low temp cooking. They don’t deteriorate in the 2.5 hours it takes to cook them low temp. and they do fine cooked all the way up to 57 C –a perfectly safe temperature. 

So how do you low-temp a striper?  They won’t fit in a vacuum machine and you don’t want to poach them.  A striper just fits into the wide roll foodsaver bags, and for a while this is how we cooked them.  I’ve been told that few things are more amusing than watching Nils and me try to get the foodsaver to vacuum the air out of a 42 inch long food saver bag that’s  bent into a U and full of fish and oil.   The “U” is a necessity: otherwise the fish won’t fit in the fryer.

One serendipidous day we had to cook a striper and we couldn’t locate any foodsaver bags — so we just filled our circulator bath with oil.  Easy, delicious, though more expensive (cause you need all that oil).  It’s our preferred method now, and here it is on a 40 inch striper:

Cleaning the fish. Scale, remove the gills, scrape the spine and rinse under copious water. Salt the inside and stuff with lime, lemon, orange, onions, ginger, cilantro and Thai basil. Use a trussing needle to run butcher twine through the tail and lower jaw. Tie the fish in a U.

The Fish in the oil. The quart containers and jugs in the oil are simply to take up space so less oil is needed. We had to throw a couple more quart containers of water in after this picture was taken to get the fish fully covered. The fish cooked at 57 C for 2.5 hours.

The fish after we took it out of the oil. Let it cool a few minutes. If desired, use the circulating oil to fry.

Flour up the fish. Nils prefers water-chestnut flour. We did not have any so we used AP flour.

Fry it up. The fish stuck out of the oil so we had to ladle hot oil over the top.

The finished striper, pla pad prik style.

Umami Nation: Kombu Dashi Smackdown

posted by Dave Arnold

Kombu, a variety of giant kelp (seaweed), is a cornerstone of Japanese cooking. Kombu is particularly high in free glutamic acid—the umami maker—but its flavor is otherwise rather delicate, so it is an excellent source of MSG.  By the way, glutamic acid + sodium = MSG. (You’ll get much more on MSG and umami in our upcoming post: Umami Nation: MSG the Superspice—the Headache is in Your Head.)  This post is about kombu broth.

Several types of Kombu are used in Japanese cooking.  For a discussion of kombu, I refer you to this website or this book.  We used ma kombu which was harvested—as many good things are—in the cold waters off Hokkaido, Japan’s northernmost main island. Yuji Haraguchi of True World Foods, a premier supplier of fish and Japanese products (we buy our fish for ike-jime from them), brought us the kombu.

Ma kombu. High quality stuff from Hokkaido. Brought to us by True World Foods.

Most traditional books will instruct you to place a piece of kombu in cold water and then heat that water until it just begins to bubble, upon which you immediately remove the kombu. But recent work in Japan has shown that optimal glutamate extraction is actually obtained by steeping kombu in 65° C water for about an hour. Several years ago, when we first heard about temperature regulating kombu stocks, we told a group of Kaseiki chefs that they might want to use an immersion circulator. They looked at us like we had three heads (in fact we had only two). Undaunted, we vowed to thoroughly test kombu stocks in the circulator. Two and a half years later, we finally got around to it.

Setting up the tasting.

Setting Up the Test
The tests: we would make one broth traditionally, and one like the Kaiseki do—by attempting to regulate water temperature to 65° C on a typical stove.  After carefully reading the dashi sections of some our favorite books, we settled on 10 grams of kombu per liter of liquid—though intuitively this seemed low to us. For a third test we would circulate the kombu in water at 65° C.

We could think of two possible reasons the circulated broth wouldn’t be as good (or better) than other techniques: 1) if the air churned in by circulation had a negative effect, or 2) if the crappy heat control of the stovetop was actually a benefit; i.e., if temperature fluctuation somehow made the stock better. To control for the air problem we added a test of some kombu circulated in a vacuum bag. It didn’t take long for Nils and I to realize the bag was probably a good idea anyway, because we would get some vacuum-infusion benefits.

Yuji from True World also suggested we try some cold infusion, so we added a 10 gram/liter overnight infusion to our test, a 10 gram/liter overnight vacuum infusion, and a 20 gram/liter overnight vacuum infusion. We never heated these infusions with the kombu in them. As a final test, Yuji suggested we heat the regular overnight infusion in the traditional way (until bubbles start to form), with the kombu in it. We ended up with 8 different kombu broths, and we tasted them blind.

What We Didn’t Test

• We didn’t test a temperature range. We didn’t do 60° versus 65° versus 70° C. Next test.
• We didn’t test the level of free glutamate in the broth. Most literature will tell you this number is important. But we can’t measure free glutamate here, and we thought it much more important to judge the broths on taste alone.
• We didn’t test the interaction of the kombu broths with other umami-producing ingredients like bonito flakes (katsuobushi) or shitake mushrooms. Bonito flakes have inosinic acid, and shitakes have guanylate, both of which act synergistically with the glutamic acid in kombu to create a lot more umami than kombu alone.
• Often a kombu is re-used to make a secondary dashi after the primary broth is made. Some of the extraction methods we used rendered the leftover kombu virtually tasteless, which would make a secondary dashi impossible.  So we didn’t test secondary dashis.

The Results

Kombu Tasting Results. We tested three different groups (red, blue, and green), and then pitted the winners of each group against each other to figure out which kombu dashi reigned supreme. The red block tested methods of making kombu dashi at 65° C: directly in a circulator, in a vacuum bag in a circulator, and by trying to maintain 65° C on a stovetop. The blue block tested cold infusion techniques: in a vacuum bag at 20 grams kombu per liter, in a vacuum bag at 10 grams kombu per liter (traditional amount), and 10 grams of kombu in a liter of water without a bag. The green group pitted traditional kombu dashi--10 grams per liter started cold and just brought to the bubble and strained, versus cold infused then heated dashi also at 10g/liter without a vacuum bag.

Vacuum bagged 65° C circulated kombu stock reigned supreme!

The verdict was decisive. Unanimous and unequivocal.

In the future, we will test vacuum bagged 65° C kombu at 15 g/liter and at 20 g/liter, because 20g/liter won the cold infusion category.  We should also try cold-vacuum-infused-then-heated broth.  We think it would win.

Your tasting panel doing a kombu-dashi skoal: Yuji Haraguchi, our buddy from True World Foods and the guy that brought the kombu; Dave; Christina Wang, director of education here at the FCI, kombu lover; Nils.

Road Skoal: San Francisco

posted by Nastassia Lopez

(Hey, what is this Skål Project anyway?)

Flying across the country to skoal Merle Haggard gave us a good excuse to have some San Francisco chefs, writers, and culinary friends pose for a skoal shot. Dave, Nastassia, Harold McGee, Flo McGee (Harold’s daughter) and the official Road Skoal Photographer, Travis Huggett, gassed up, fed parking meters, and drove circles around San Francisco with a cooler of cold Aquavit in pursuit of one thing: spreading the skoal to the Bay Area.

The Road Skoal Team with Chef Daniel Patterson in the alley next to his restaurant, Coi.

We set up our first Skoal Station at the Ferry Building Marketplace, home of San Fransisco’s famed farmer’s market, where local farmers and artisan producers sell fresh goods to chefs and locals:

The PR force who helped us set up our Ferry skoals:

Eleanor Bertino: President of her eponymous public relations firm that specializes in San Francisco Bay Area and national media for acclaimed restaurants, artisan food products, and sustainable initiatives. On the Board of Slow Food USA.

A famous NorCal Farmer:

Farmer Al Corchesne: Co-owns the 133-acre Frog Hollow Farm in Brentwood, California, with his wife Rebecca. Famed for his glorious peaches and his signature overalls.

(9 am is the middle of the day for Farmer Al –he had two shots. Seriously though, his fruit is delicious.)

A purveyor of some of the best rarer-than-rare Chinese teas:

Roy Fong: Founder and proprietor of Imperial Tea Court - the first traditional Chinese teahouse in America; an ordained daoist priest; helped restore one of the oldest Tang Dynasty tea sites in Zhejiang, China.

He specializes in aged pu-erh tea.  He has a warehouse in Oakland where he ages teas for up to 20 years.

A cook and expert on India’s rapidly dwindling Parsi population:

Niloufer King: Anthropologist, food scholar, teacher and cook; author of My Bombay Kitchen; oversees the preparation of a Parsi New Year’s dinner at Chez Panisse.

From the Ferry Building we drove to Noe Valley, where we met husband and wife team of Sardinian restaurant, La Ciccia:

Massimiliano Conti: Chef of La Ciccia; native Sardinian; former sommelier; forgot to tell his wife that he signed her up for a skoal.

Loretta Degan: wife of Chef Massimiliano; front-of-house at La Ciccia; former concierge at the Mandarin Oriental.

Insieme:

Massimiliano and Loretta: Salute!

We drove back and forth between Bar Baretta, Coi and Incanto several times to track these next guys down (New Yorkers+driving+scheduling in the most laid back state in the country=disaster).

Dinner night one:

Daniel Patterson: multisensory chef at Coi; obsessed with the interplay of taste and smell; writes for the New York Times. Don't write an article about him and mention the strip club next door. He hates that.

The neighbors.

And desserts:

Bill Corbett: Pastry chef at Coi; worked with Wylie at WD-50; native Canadian. Wants to make kick-ass vegan food someday.

Dinner night two:

Chris Cosentino: Chef at Incanto, Food Network star, and owner of Boccalone: Tasty Salted Pig Parts; lover of all things offal; part-time professional bicyclist.

And the bartender who saved the Road Skoal crew from thirst on multiple occasions:

Ryan Fitzgerald. Mixologist extraordinaire at Bar Baretta. He is wearing his signature I Hate Cocktails T-shirt signed by Dave Wondrich. The skoal was so intense it knocked his pony-tail out of its holder.

From San Francisco we drove two hours east for the Merle skoal in Modesto. As soon as Merle left the stage, we high-tailed it 3 hours north to Sonoma to skoal Paula Wolfert and her husband Bill Bayer:

This lady owns more than 100 clay pots (she’s been collecting for 50 years):

Paula Wolfert: author (and James Beard Award winner) of five cookbooks on Eastern Mediterranean cooking; self-professed clay pot junkie.

This man thinks of ways to kill people with clay pots:

Bill Bayer: author of crime and sexual psychopath novels; native Shakerite (an oxymoron?); after graduating Harvard made propaganda movies for the United States Information Agency in Vietnam.

Together:

Paula and Bill: we let them keep the bottle.

New! Liquid Nitrogen Primer.

posted by Dave Arnold 

You asked for it, you got it. A liquid nitrogen primer. 

LN Dewar

Nils and I wrote an article on freezing for the September 2009 issue of Food Arts Magazine. The piece included a short section on liquid nitrogen (LN or LN2), and I have greatly expanded it here for the blog. Important: we make no claims to inventing any of the techniques presented here. They are all pretty standard. Please, discuss who-came-up-with-what-first somewhere else. This is simply a primer.

The sections are:
I. Introduction:
II. Safety (important stuff):
III. Getting and Storing LN:
IV. Some Applications (cool stuff, most of the pictures): 

I’ll just give you the Introduction below. 

Liquid Nitrogen is about as cold as you can get in the kitchen, registering a whopping negative 196 degrees Celsius (-321 F) … and it’s non-diluting and non-contaminating to boot. Despite its preposterous coldness, liquid nitrogen has only 15% more cooling power than the same amount of ice at 0 Celsius. This counter-intuitive fact leads many chefs to underestimate the amount of liquid nitrogen they need for a given task, like making ice cream.

Ice cream is typically the first thing people make with LN. Theoretically, it should be the best you can make because the mix freezes so quickly – and the quicker the freeze, the smaller the ice crystals, and the smoother the ice cream. But commercial ice cream machines make sufficiently small ice crystals for most palates, and it’s very easy to over-freeze portions of liquid nitrogen ice cream. So your LN ice cream results might not be as great as you expect.

But there are many other fantastic LN applications. You can turn fresh herbs into powder, separate citrus fruits and raspberries into jewel-like pieces, and freeze alcohol to make liquid centered treats. Be warned: liquid nitrogen is addictive and mesmerizing in the kitchen.

Here is a taste of some of the techniques in the primer:

Some of the techniques in the primer.

On to the primer…

Ladies and Gentlemen, Merle Haggard Skoals.

posted by Dave Arnold

(Hey, what is this Skål Project anyway?)

Merle Haggard, shot by Travis Huggett.

We are starting the new year off with a bang. We flew across the country and skoaled country music legend Merle Haggard –one of our musical heros.

Readers might remember our excitement at the opportunity to meet Mr. Haggard, expressed here.

Merle Haggard. Country music legend. Badass.

How do you like that?

It gets even better. Merle’s wife Theresa sings backup and agreed to skoal too.

Theresa Haggard. Married to Merle Hagggard. Cured him from being the running kind.

And there is absolutely nothing Cooking Issues enjoyes more than a good couple’s skoal.

Merle and Theresa Haggard. What country music is all about: a man, a woman, and a little booze.

Merle and Theresa were incredibly gracious, as was Frank Mull, Merle’s long-time road manager. They warmed to Cooking Issues as soon as I described myself as a high-tech moonshiner.  Merle’s two favorite liquors are tequila (preferably blanco), and George Dickel 86 proof Tennesee whiskey.  Theresa likes margaritas.  They were OK with Aquavit. 

The back story in photos:

We flew into San Fransisco, but the concert was in Modesto.

Modesto is about as far away from San Fransisco as two hours in a car can get you.

We put our Aquavit on salt and ice to keep it freezer-cold on our trip from San Fransico to Modesto

Merle was signing guitars for charity.

"I'm gonna do what?" Dave explaining the skoal project to Merle Haggard. Frank Mull in the background.

The concert was fantastic. Merle’s still got it. Both his wife Theresa and his youngest son Benion are in the band. At 17, Benion can really rip it up on guitar.

Backstage at the concert.

All photos by Travis Huggett except the shot of Modesto, courtesy of my crappy Iphone.

Bubbles

posted by Dave Arnold

Happy New Year.  If you are more interested in a bottle of bubbly than in bubbles, perhaps I can interest you in one of our old posts, a tutorial on how to saber a bottle of bubbly.

Carbonating

Everyone here at Cooking Issues is a huge fan of bubbles.  Let’s just say we know from carbonation. When some new science came out a few months ago on the taste of bubbles, we were intrigued. The Taste of Carbonation, in the October 2009 issue of Science Magazine, describes carbonic anyhydrase 4, an enzyme that allows us to taste CO2 (carbon dioxide –the bubbles).  For those of you not hip to science publishing, getting an article on bubbles printed in Science is a big, big deal.  The theory: In your mouth, CO2 is converted into bicarbonate ions (HCO3-) and protons (H+).  The protons are acid, and are sensed by your sour receptors.  That’s it.  Mice that had no sour receptors had no response to the carbonation, and mice that didn’t have the enzyme couldn’t taste carbonation.  This research came about, in part, because a scientist who was also a mountainclimber was taking the anti-altitude sickness drug Acetazolamide, a carbonic anhydrase inhibitor, and noticed champagne tasted like crap and figured there might be a link between carbonic anyhydrase and the taste of CO2.

This research made me hopping mad.  For years I have been railing against the long-standing explanation that carbonation’s taste comes from acidity.  The tired, old explanation is that CO2 dissolves in water to form carbonic acid.  Somehow, the combination of bubbles plus the cabonic acid makes the taste of cabonation. That is rubbish.  First, most CO2 does not get converted to cabonic acid –it exists as dissolved CO2. Second, If you drink seltzer in a hyperbaric (high pressure) chamber where there are no bubbles, it still tastes like seltzer.  Third, and most important to me, I can put N2O (nitrous oxide) bubbles into a highly acidic beverage like lemon juice and water, and it doesn’t taste like seltzer with lemon — it tastes like lemonade, because nitrous tastes sweet. 

This research brought the whole argument back to acidity.  I was dumbfounded.  I mean, selzter tastes like selzer, not like acid.  I called up Dr Charles Zuker, one of the senior authors on the paper, who just moved up the street from me to Columbia University.  Our converstion went like this:

 ”What is the deal?”

“Well, CO2 is perceived as acidity.  If you blow pure CO2 onto your tongue you percieve acidity before you percieve pain.  CO2 also stimulates pain receptors.”

“Why doesn’t lemonade with nitrous taste like soda?”

“Ahhh.  When you drink lemonade with nitrous, the acidity is sensed all over your tongue at the same time at the same concentration.  When you drink lemon soda, the acidity levels change all the time all over your tongue due to the activity of the carbonic anhydrase enzymes.  The random, changing pattern of acidity on your tongue is percieved in your brain as carbonation.”

“So if I could make a drink with tiny pockets of acidity it might taste carbonated?”

“Yes.”

Wow.  That was some food for thought.  I’m still digesting it.

Holiday Skoal! Special Bonus: Holiday Pictures and Dave’s Favorite Christmas Cookie

posted by Nastassia Lopez and Dave Arnold

(Hey, what is this Skål Project anyway?)

To celebrate the season of good cheer and good eats, we’ve compiled some of our favorite food-folk skoals.

First up, a gang of New York City’s top chefs:

Paul Liebrandt: Chef and Owner of Corton, one of Gotham Magazine's Top 100 Bachelors of 2009; native of Zimbabwe.

Craig Koketsu: Chef at Quality Meats; not afraid to get creative with tofu; started the clothing line Annelore with his designer wife, Juliana Cho.

Anita Lo: Chef at Annisa and consultant for Rickshaw Dumpling Bar; Michigan native with a degree in French from Columbia University; ruthless contestant on Top Chef Masters.

Dave Pasternack: Chef at Esca in Hell's Kitchen; fisherman from the age of 5; a pioneer of New York's "Crudo Craze."

Jiro Iida: Chef at Aburiya Kinnosuke; master of the ancient Japanese technique of robata grilling; one of our favorite post-skoal faces.

Corwin Kave: Chef du Cuisine at Fatty Crab; ex-model; a Scorpio; Brooklynite.

And people who like to eat their food and write about it:

Gillian Duffy: Culinary Editor at New York Magazine; author of 'Hors d'oeuvres'; after marrying a Captain in the Royal Artillery and hosting Army Dinner Parties in her twenties, she and her husband lived and cooked on a 70 foot yacht for a year off of Ibiza.

Will Blunt: Managing Editor of Star Chefs; native of Washington DC (with a background in politics); please give us a better time slot in the next Star Chefs Convention!

Daniel Gritzer: Writer for Time Out's Eat Out section; former sous chef for Cesare Casella at Beppe; expert in Capoeira; makes a damn good mojito.

Peter Kaminsky. Award winning author of books on cooking and fishing --two of life's great things. When it comes to cooking, the pig is his muse.

Too Many Cookies: Making and Shipping FCI’s Holiday Cookies, After Which We Needed A Skoal

Last week we baked 3,678 chocolate chip cookies. The pastry chefs, student volunteers and tech crew baked and packed them in 6 hours flat. We spent the rest of the week trying to ship them to Iraq.  We’re good at cooking but bad at shipping:

Dave and Celio cranking it out.

Cookies Cookies Everywhere.

Some of the team behind it all (we're missing the guys from pastry and the non-intern students - thanks guys!)

Man they have a lot of stairs at the 34th street Post Office!

Here are our cookies at the post office.

Nastassia-height cookie boxes. She is the one in the middle.

For the Holidays: Dave’s Favorite Christmas Cookie

Ricciarelli are traditional almond cookies from Siena. These aren’t stricly traditional, we add lemon to the traditional orange, use fresh zest instead of candied peel, and add more vanilla. We also use more egg whites than normal, which makes for a chewier cookie. The key to the flavor of riciarelli is bitter almond. Here in the US we usually get this flavor by using almond extract. You can get the real thing, however, in stores in Chinatown. The package will be labeled “bitter almond,” or “apricot kernel,” or “northern apricot.”  They contain amygdalin, which decomposes to cyanide, so don’t eat a lot of them. The interns were popping them like candy. We said, “hey, that’s poison.” They laughed and kept eating. Guess we joke about that stuff too much.

We used the Santha grinder to make the dough, but you could get almost the same result in a robot coupe. or by using almond paste. Here is the recipe:

1800 grams blanched almonds
1300 grams granulated sugar
32 grams bitter almonds
15 grams salt
25 grams lemon zest
45 grams orange zest
4 scraped vanilla beans
90 grams ap flour
90 grams confectioner’s sugar
7 egg whites
100 grams granulated sugar

Bitter Almonds

Grind the nuts in a Champion juicer. Slowly add everything except the egg whites and last 100 grams of sugar to the Santha and process 4 hours (this process is a hassle).

This is how the dough should look in the Santha. Whip egg whites with 100g sugar and fold into dough.

Turn dough out onto a surface dusted with powdered sugar. Cut into diamond shapes and bake at 300F till they just take on color.

The Finished Cookie

Crowded Wet Mushrooms. A Beautiful Thing.

posted by Dave Arnold

Turns out the way we are taught to sauté mushrooms is dead wrong. If you want the highest quality mushrooms what you want to do is soak your mushrooms and then crowd the hell out of them in a pan. Let me explain:

For best results, soak your mushrooms, then crowd them.... Really.

We are all told not to wash our mushrooms because they will soak up water. One of the demos we do in the Harold McGee class is to disprove this myth by cooking two batches of mushrooms side by side: one that has been “brushed off” and one that has been soaked in water. The soaked mushrooms do take on water, but that water cooks off in the pan. We send the mushrooms out to the audience and they taste pretty much the same. As a bonus, washed mushrooms are a heck of a lot cleaner than brushed-off mushrooms. Myth busted –you can wash your mushrooms without worry (this part is not news to many of us).

The problem with the demo has always been that we haven’t controlled the variables well. In particular, salt and oil levels were not kept the same from batch to batch. This time, we resolved to do better. We weighed out two identical batches of mushrooms. Half were brushed-off. Nils first sliced and then soaked the other half just so they would really soak up a bunch of water. To make the test really severe, I decided to cook the soaked mushrooms in one batch in an extremely crowded pan, and the dry mushrooms in 3 batches with plenty of room. We weighed out identical amounts of salt and oil (this is the crucial part) and began cooking.

As we expected, the soaked crowded mushrooms formed a soupy mess in the pan. The dry mushrooms didn’t stew and cooked quickly. Here is where it got weird. The dry mushrooms ended up absorbing all the oil. In fact, I had underestimated the amount of oil they needed. They wanted more. I couldn’t add any more oil, however, because it would have ruined the experiment. When the soaked and crowded mushrooms had finally evaporated all their extra water and stated to sauté, they didn’t absorb all the oil. When they were finished, a significant amount of oil was left in the pan. They looked as good and tasted better and less oily than their dry cousins –by a lot.

Our explanation: While the mushrooms are boiling off their water, they aren’t absorbing oil. By the time the boiling stops they have already collapsed, so they aren’t as porous as a raw mushroom and don’t want to absorb oil. The dry mushrooms start absorbing oil from the get-go.

None of us had expected this result. Just goes to show what you can learn when you pay attention.

P.S. I also added all the salt at the beginning of the cook, for whatever that’s worth.