Peter Hertzmann’s floating island: the evolution of a dish

One of the most gratifying aspects of blogging is the private interaction with readers through emails. I love reading your thoughtful questions, comments, and ideas. It's these interactions that often become fuel for the fire.
Two years ago, I worked with a young cook who had mentioned a book that had helped him to advance his knife skills: Knife Skills Illustrated by Peter Hertzmann. Imagine my surprize when a few days later I found mail from Peter in my inbox!
Peter Hertzmann* and I have exchanged dozens of emails since then and I've always found his insights stimulating. Last month he began sharing a misozuke project (complete with photos) that was particularly inspiring and I asked if I could share its evolution here on the blog.
This is how it began:

Hi Linda,
You've created a miso-zuke monster—me.
I've now done oysters, scallops, endive, radishes, and cucumbers. I originally was interested because of your article where you pickled some egg yolks. I wanted to do quail, rather than chicken eggs. I was never able to get the eggs cooked just right, so I sort of gave up. Then a couple of weeks ago, I started playing with peeling eggs with acetic acid. In the case of quail eggs, an overnight soak in white vinegar leaves a shell-less egg with both of the membranes intact. The egg feels a bit like a full water balloon. I threw a few of these eggs in shiro miso and nothing happened, or so it seemed. After two weeks, they appeared for all intents and purposes the same as when they have been first immersed in the miso. So I'd thought I break one and look inside. The membrane was a bit tough, but I was able to pick a small tear in one end with some forceps. The white came gushing out—not quite as fluid as water, but not really a jelly. Inside was a firm, pickled yolk that I could carefully pull and then wash all the white away from. The taste was definitely that of a yolk, but the presence of miso was also pronounced. With a light sprinkle of ichimi, the task was marvelous.
A new dozen is now pickling to see if this was a fluke, or not. Thanks again for turning me on to this technique.

Several things interested me about Peters process:
1. dissolving the shell with vinegar allowed him to pickle the whole raw egg much more efficiently than waiting for the miso to penetrate the shell. This step alone opened up many ideas.
2. the texture of the cured yolk.
3. the miso-flavored egg whites.

A few weeks later, I received the following email:

Here's an update on the quail eggs. Like before, I removed the shells by soaking them in white vinegar (6% acetic acid) overnight. The following day I rubbed off any remaining shell with my fingers. The eggs, minus their shells, were immersed in shiro miso for two weeks. After rinsing they looked like…

Other than appearing a bit browner than originally, their appearance and firmness was unchanged. I used a pair of small 45° forceps to tear a small hole in the tapered end of each egg and drained them into a bowl. The "white" was as viscous as water and brown in color…

After removing from the membranes and rinsing, the yolks, which were firm but not hard, looked like…

I decided to cook the whites. I placed them in a small glass bowl and covered it with plastic film. This was placed in simmering water until the whites no longer jiggled. After cooling, the texture of the cooked whites was similar to a grainy custard. They tasted very much like the miso they had soaked in. I had hoped that they would cook hard so that I could sieve them for the final dish, but that was not to be.
About 4 hours later I plated the eggs…

As you can see the yolk weeps. (The flower is a rosemary blossom.)
I'm intrigued by your suggestion to make a meringue with the whites. These eggs didn't produce much white to work with so I'm going to try the same process with a chicken egg so I can get more white.

Then a few weeks later I received the following update:

Here's the followup on the previous email. I used vinegar to once again remove the shell from an egg; this time a chicken egg. I started with two but one broke with moderate handling during the shell-removable phase. The remaining egg was covered with shiro miso for 21 days. At the end it looked like below.

I should have measured the size after the shell was removed because I think it was then it grew. I should have weighed it also. Oh, well. It's obviously larger, but I can't say why.
I opened the egg onto a plate.

Normal eggs have four layers of albumin, two thick and two thin. It now appeared to have three distinct types of albumen.
The yolk was similar to an egg cooked at 64°C (and I did roll, freeze, and cut this into ribbons). In the picture I had already crushed it a bit with my fingers.

The white beat fairly normally in a stand mixer.

And they seemed fairly stable, at least for an hour before they were all destroyed.
I tried doing two things with them. The first was to make sort of a floating island in dashi. As soon as the egg white hit the hot soup, it started to collapse.

The final texture was similar to a kitchen sponge, but the flavor in the dashi was quite nice. It would be interesting to see if a little xanthum gum or versawhip would help stabilize them in the heat. I also tried some meringues, but they were a complete disaster. Besides collapsing most of the way, they turned brown like a cookie and tasted very salty. Maybe if they were stabilized they would have fared better. IN their plain form they weren't stable enough to pipe, but if they were, it would be interesting to make soup croutons out of them.

In a followup email, I asked Peter some questions about his experiment:

L: I'd be interested to know why the egg grew, or swelled.
P: I would too. I wonder if the hydrostatic pressure of a normal egg is slightly positive so that it expands once the restraint of the shell is removed. I guess it would be possible to conduct a small experiment, but I'm not ready to sacrifice a dozen eggs at the moment.

L:You said you made meringues, but they weren't stable… I'm assuming that you didn't use sugar because of the savory application. I like the idea of a salty/sweet meringue. Or perhaps a macaron?
P: Yep. No sugar, or anything else for that matter. Give the salt and sweet meringue a try and let me know how it is. I was thinking just savory, since the miso flavor is pretty pronounced.

A short while later, I received another email from Peter expressing a desire to use methylcellulose to stabilize the 'floating island' and he asked about ratios. I made some suggestions, and he responded:

I started with your suggestions and, as is normal for me, went my own way a bit. I also downloaded the Methocel tech sheet. It sounded like hot hydration would work better for me since I'm working in very small quantities.
I hydrated 1g of Methocel F50 in 20ml of simmering water, water that was boiled in microwave and then measured with a syringe. I stuck this in the frig for a few minutes. It was about 18°C when I pulled it out. I separated 1 extra-large egg white, about 30g. When i whisked the egg white and Methocel/water together is seemed to foam fairly rapidly so I decided to try whipping it in the KitchenAid. This took about 15 to 20 minutes to form soft peaks. I spooned this into hot hon-dashi to cook. I tried Chang's method of a 30-second steam followed by basting. I also tried a 60-second steam with less basting. The later was easier to do since I wanted to cook four at a time. In either case the linear shrinkage was about 50%, but still acceptable. I added ao-nori to the mixture part way through to give it a bit of color. I shot the picture quickly with my iPhone so the color is a bit off.

The final mouth feel of the island was similar to a spongy hard-cooked egg white. Not the same as a floating island made with sugar, but very interesting. I feel good about the results, at least enough to drop a couple more eggs into a vinegar bath and start the pickling again. I'd like to eventually serve the egg white in a double-strength chicken consomme and load the egg white with a fresh herb, maybe oregano. Everything should be ready by May 6th. I already have some guests scheduled for dinner that night. Little do they know…
As always, thanks for your help.

*Peter's bio: Cooking for Peter is a serial obsession. After spending 25 years studying Chinese cooking, history, and culture, in the mid 1990s, Peter started applying the same energy to French cookery. Over a period of 15 years he taught himself to read French, studied the history of dishes back to the 14th century, and worked in eight different restaurant kitchens in France to hone his skills. In 1999, he started an e-zine about French gastronomy and in 2011 added a weekly blog of amuse-bouche and mignardise to the site. In 2007, Peter wrote the book Knife Skills Illustrated: A Users Manual, now used for teaching in a number of cooking schools and restaurants. He has taught knife-skills classes around the country and in Canada. He has made many television appearances, including The Martha Stewart Show. He recently demonstrated knife skills for four hours at the Exploratorium for their After Dark: Gastronomy event. Nowadays, besides teaching recreational classes, he teaches knifes skills and general cooking twice a week at the San Mateo County Jail and twice a month at JobTrain, a vocational training center specializing in providing job skills for the underprivileged. As a charter member of The Butchers Guild, Peter is currently editing the official Guild Butchery Glossary. In July, he once again will be presenting a paper at the Oxford Symposium on Food and Cooking. The subject for this year’s Symposium is Wrapped and Stuffed Foods, and Peter will be addressing how Modernist cuisine relates to the issue.

butternut squash fusilli

There's an hors d'oeuvre on our fall/winter catering menu that we refer to as "the squash box". It consists of a hollow cube of roasted butternut squash, filled with goat cheese and crushed pistachios. When we serve them inverted and lined up on trays, they appear to be simple bite-sized blocks of squash— the hidden filling comes as a surprise. The squash boxes exemplify the combination of appealing flavor and clean presentation that we strive for in our passed hors d'oeuvres, so naturally, we were pleased by their popularity. But back in the kitchen, they were a real pain in the ass to make.
At first, we hollowed them by scoring 1/4" thick walls with a paring knife, then meticulously removed the centers with a melon baller. This was manageable when making a few dozen, but when the numbers stretched into the hundreds, we had to rethink the process.
Chef Martin is a great thinker, a creative problem solver, and a lover of tools. His first attempt at a solution was to have a square metal die fabricated to score the inner wall. In theory, it should've worked perfectly, but in reality, the metal was too thick and split the walls of the boxes. Undeterred, he pulled out the power tools— specifically, a drill fitted with a Forstner bit. It was a beautifully quick and effective solution to a previously tedious task.
Here's a short clip of Martin in action. Please excuse his parting gesture—apparently, his hands are not a fan of the camera.

Delighted as we were by this streamlined solution and the clean holes, I was more interested in what came out of them: long, coiled ribbons of butternut squash that looked identical to fusilli pasta.
Here's a closer look:

In this by-product of the squash boxes, I saw an elegant alternative to vegetable pasta. But cooking the butternut squash fusilli posed a critical problem. I tried every possible application of heat: wet, dry, slow, fast, but in each instance, just as it passed into a palatably tender stage, they would go limp and lose definition. I knew the solution was somewhere in the folds of my memory, ready to access, but there I failed, too.
Memory is a curious thing. Sometimes it's as direct and linear as a gunshot, sometimes it's like fishing in a labrinth.
I felt a tug on the lure while reasearching nixtamalization for a pickling project. It bit down in my memory of the 2011 Star Chefs Congress. When I reeled it in, at the end of the line were 2 gleaming nuggets of information.
The first was courtesy of Andoni Luis Aduriz, who, in a workshop, demonstrated a fossilization technique where salsify was soaked in a lime (the mineral, not the fruit) solution to firm the surface before cooking. From my memory, his claim that "any fruit with pectin will react with lime to make calcium pectate".
The second nugget was from Paul Liebrandt's mainstage presentation from the later that day. In a similar technique, he used calcium lactate to form a skin on the surface of jerusalem artichoke, allowing it to keep it's shape while the interior cooked to a creamy texture, without loss of moisture.
So, it seemed there were two possible solutions that produced parallel results. One, alkaline and caustic, the other a neutral salt.
I went with the calcium lactate. In the photo below, you can see the results. In the foreground is the squash that soaked in a 1% calcium lactate solution for 2 hours, then air dried, and roasted— tender, but still defined. In the background is the untreated squash roasted on the same pan— limp in comparison.

Solutions, like a great catch, are worth waiting for.
That's an easy one to remember.

butternut squash ✢ black kale ✢ goat gouda ✢ kale stem

amazake strawberry kinome

It was on a blustery winter afternoon that I first sampled amazake. It came in the form of a traditional Japanese beverage, served warm with a sprinkle of grated ginger. Learning that it was essentially just fermented rice and water, I was amazed at the depth of flavor and sweetness that koji had coaxed out of the rice. And there was a richness about the way that it felt in my mouth that reminded me of dairy. It was, I was told, the vegan eggnog.

Recently, I had a visitor come to my home to see my newly remodeled kitchen. Because he writes about food, I wanted to cook for him and was eager to showcase some of the products that I had fermented. For dessert, I made an amazake ice cream based on the beverage, using coconut water for added flavor. It was really an experiment, as I was curious about the texture of churned and frozen amazake. The result was not as creamy as I had hoped and the inherent sweetness had muted to a mere whisper— which typically occurs with freezing. We both agreed that it showed promise, but needed work.

We also agreed that the flavor of strawberries and kinome with the amazake was quite special, so that part of the dish would remain intact.

Days later, I made a new ice cream with pureed amazake, cream, and sugar. It was a vast improvement over the original, but I couldn't help but feel that I had missed an important opportunity.

As someone who cooks customized food for a living, the upsurge of food intolerances is a salient concern. Coeliac disease, lactose intolerance, and food allergies are serious conditions that I have learned to make allowances for. Then there's an ever-increasing number of people who choose to refrain from entire food groups such as dairy or meat, or follow 'lifestyle diets' that exclude white powders and saturated fats. Add to that, the political eaters who prohibit foie gras, veal, unsustainable fish, factory farmed proteins, and unorganic produce; or picky eaters who refuse to eat (for example) anything with garlic or onions, and you can begin to see why chefs are so frustrated— some to the point of choosing to make NO allowances.

I don't have that luxury.

When a guest at a dinner party unexpectedly announces that there is something on the carefully planned menu that they can't or won't eat, I have to accommodate them. No excuses.

The upside is that when you feed someone with special dietary needs a delicious and satisfying meal that doesn't offend their bodies or minds, they are exceedingly grateful. Altruism aside, a happy client is always a boost to the ego.

Over time, I've learned to make adjustments to fit most diets, but vegan desserts continue to challenge me. In a pinch, I can turn to fresh fruit and sorbet or granita, but that often feels like a copout. So I reexamined amazake's potential to add texture, natural sweetness, and moisture to desserts that otherwise rely on dairy products and refined sugars, and I decided that an ice cream was a good place to start. To the pureed amazake, I added coconut milk for richness, rice syrup for added sweetness, and guar gum to improve the mouthfeel. The addition of sichuan pepper was specific to this dish to enhance the flavor of strawberries and kinome.

While I'm pleased with how the amazake ice cream turned out, if I were given a choice between the sweet cream version and the vegan one, I would invariably choose the former.

I'm grateful that I have that luxury.

amazake ice cream ✢ puffed forbidden rice
strawberry ✢ sake ✢ kinome

vegan amazake ice cream

400g coconut milk
260g amazake
20g rice syrup
5g vanilla
4g lightly toasted and ground sichuan peppercorns (optional)
3g guar gum

Place all ingredients in a high speed blender and blend 3 minutes, or until very smooth. Scrape mixture into an ice cream freezer and proceed according to manufacture's directions.

kasu egg

Think you're looking at soft boiled eggs?
Look again.

While making kasu zuke egg yolks, I was struck by how natural the pale kasu looked surrounding the yellow yolks— a visual inspiration for a faux egg. The next step was to make an albumen with the flavor of kasu and the texture of a cooked egg white. After experimenting with various hydrocolloids, the synergy of gelatin, agar, and gelated rice starch produced a convincing (and delicious) fascimile.

kasu eggs
makes 6

You will need 2-part egg molds with a pouring hole at the top. The molding process is a bit fiddly— the first pour should be allowed to set just enough to support the weight of the yolk, but soft enough to meld with the second pour.

1200g water
180g basmati rice

Bring water to a boil. Add rice and reduce heat to a simmer. Cover and cook for 25 minutes, until rice is very soft and tender. Drain rice, reserving the cooking liquid. Cool.

190g cooked, drained basmati rice
280g reserved cooking liquid
60g compressed kasu
6g rice bran oil
5g mirin
4g salt
1.8g agar
1g gelatin

6 65℃ egg yolks (whole eggs cooked at 65℃/149℉ for 45 minutes, then peeled and separated from whites)

Place rice, liquid, kasu, oil, mirin and salt in blender and blend until smooth. Sprinkle gelatin and agar over top of mixture and blend for 10 seconds. Scrape mixture into a saucepan. (At this point, mixture will be thick, but will become fluid upon heating). Cover and heat mixture over low heat until it comes to a simmer. (It is important to keep pan covered while heating as evaporation will cause it to thicken). Quickly pour mixture into bottom half of 6 molds until about 2/3 full. Cover pan and keep warm. Place molds in freezer until barely set (mixture will yield slightly when pressed with a finger, but is no longer liquid. Center a yolk on top of mixture in each mold. Secure the top half of the mold in place, being careful to not disturb the position of the yolks. Fill the molds with the remaining mixture using a small funnel, if necessary. Carefully transfer the molds to the refrigerator and chill for at least 2 hours before unmolding.
To unmold: Submerge the molds in warm water for a few seconds to loosen. Carefully remove the top half of the molds, then invert the bottom halves over a plate until the eggs slip out.

cured shad roe

With the other shad roe sac, I'm attempting a multi-stage curing process. Here it is so far:

First, it was brined for 2 days in a 3% salt solution. Then it was embedded in a thick layer of sea salt for 3 days. Next, it was allowed to dry on a rack in the refrigerator for another 3 days until the surface was thoroughly dry. After brushing off the excess salt, it was embedded in a thick layer of red miso, covered and set in the refrigerator to ferrment for 2-3 months. That's where it is now.
After that, it will be cold smoked, then dehydrated until it is hard as wood.
The intention is to transform the shad roe into a botarga-like product with the complexity of katsuobushi.
The hope is that it will be delicious.

egg yolk cheese

These are 65C hen egg yolks that have been cured in miso for two weeks. The longer cure renders them dark and pungent. Although they were firmer than they were at 5 days, they remained moist and sticky. In order to dry them out, they were wrapped in the cheesecloth in which they were cured and hung in the refrigerator.

These are the cured egg yolks after hanging for twenty days. They've became firm enough to slice or grate neatly, with the smooth, plastic-y texture of an aged gouda. Their flavor, too, is transformed— the aging process rounds out the sharpness of the miso, creating a mellow complexity of flavor with the texture of cheese. Delicious!

olive oil poached daikon ✢ fava ✢ meyer lemon
egg yolk cheese

miso-cured oyster

Oysters can be cured in miso in less than a week. I left some to cure longer, but five days seemed to be the magic number for optimum flavor and texture in this particular batch. Of course, this could vary depending on the size of oysters and the type of miso used.

To make miso-cured oysters: Steam scrubbed oysters just until they open. Remove the oysters from shell and place them on paper towels to dry. If using shells for curing, sterilize them in boiling water for 5 minutes, then allow them to cool and dry. Spread a 1/2" thick layer of miso in the bottom of each shell. Cover miso with a layer of cheesecloth, then an oyster. Cover the oysters with cheesecloth, then another layer of miso, and finally, the top shell. Layer oysters in a sterilized container, cover tightly, and allow to cure in refrigerator for 3-7 days.

miso-cured oyster ✢ kombu aioli ✢ mushroom crisps ✢ ngo om

The assertive flavor of kombu and garlic is a good compliment to the meaty oyster and earthy mushrooms, brightened by refreshing bursts of cucumber provided by the ngo om (rice paddy herb).

After the oysters were gone, we happily nibbled on the aioli and mushrooms.

kombu aioli

6g garlic
3g salt
2 egg yolks
60g rice wine vinegar
200g olive oil
10g kombu powder*

Place the garlic, salt, egg yolks, and vinegar in a blender or food processor and processes until well blended. With the motor running, very slowly drizzle in the oil until thick and emulsified. Add the kombu powder and process briefly until blended. Scrape out aioli into a bowl, cover and let refrigerate for 2-3 hours to allow kombu to hydrate and flavors to mellow. Stir before serving.
* kombu powder can be made by grinding pieces of dried kombu sheets in a spice grinder to a fine dust.

mushroom crisps

small king oyster mushrooms lend themselves well to crisping because of their thick meaty stems.

With a vegetable peeler, shave thin slices of mushrooms by imbedding the blade of the peeler into the cap and dragging to the base. Lay the mushroom slices out in a single layer on a sheet pan and allow to air-dry for 1-2 hours, until their edges begin to curl. Lightly brush or mist the slices with a thin layer of olive oil. Bake in a 149C/300F oven for 4-5 minutes, or until they are golden and crisp. Lightly sprinkle with salt and serve immediately.

miso-cured kombu

120 days.
That's how long I'll have to wait to see what happens to kombu when it's cured with miso.
I expect the miso itself will also be interesting.

miso adaptations

Spontaneous fermentation is the oldest form of 'cooking'. Long before man understood the chemistry of how microorganisms preserved his food and heightened its flavor while making him healthier, he learned to control and manipulate the process. Each culture developed their unique specialties based on indigenous ingredients. Early travelers borrowed techniques from their neighbors and assimilated them to what was available back home.

In this spirit, I've taken the time-honored process of making miso and adapted it to the bounty of ingredients that are available in the modern world to make these trial batches. The choices were not arbitrary— they needed to fit the protein/starch profile that koji requires to feed upon. In some cases, soybeans were added to the base ingredient to boost the protein content. Many borders were crossed, but no bridges were burned.

No doubt, some will fail, and some will succeed, but that's part of the fun of discovery. Ultimately, flavor will dictate which ones will be pursued.

curry cake

Perhaps the best thing about rebuilding a kitchen from scratch is that everything will finally get a home in a place that makes sense— at last, form will follow function. My spices, for instance, were once scattered around in cupboards wherever they would fit. Soon, they will live together in their very own cabinet; on shallow floor-to-ceiling shelves, in shiny new jars, each clearly labeled.
I think they're as excited as I am.
In fact, I know they are.

I'm pretty sure that they planted the idea of spice cake in my head while I was organizing them. I tried to shake it off because, frankly, I've been baking more judiciously lately. But it was of no use. I think I heard them cheer when I pulled out my go-to recipe for spice cake, which made cinnamon, nutmeg, cloves, and ginger very happy, but caused some others to feel slighted. Five bold spices came forward and asked "Why can't we play too? You know we play well together…you always put us in your garam masala."
They had a point, but did I really want to make a curry cake?
I did.

Conceding to a new direction, I scrapped the spice cake recipe and decided that a yogurt cake would be a more appropriate platform for the savory spices. I measured them out individually, planning to blend the spices together into the finished batter, but they had other ideas. They didn't want to be muddled together. They each wanted to star in their own individual layer and be united as a cake.
"Really?" I asked, "you want me to make nine different layers?"
They did.

It wasn't as complicated as I thought it would be. I simply weighed out the batter in grams and divided by nine. Then I added just enough spice to each batch to allow each flavor to come through, but not overpower the others. This was all going well until I tasted the turmeric batter, which had the distinct flavor of musty cardboard. I didn't want to insult the old chap, but I had to be honest. He took it pretty well— considered it for awhile, then invited the other spices to join him.
"We'll be the curry layer… the reference for the cake."
What a trooper.

After the layers were baked, cooled, and trimmed, I joined them together with coconut frosting. Because turmeric stepped up and took one for the team, I gave him a distinct layer where his vivid color could be best appreciated.

As I ate the curry cake, I found myself tasting each layer with a hyper awareness, then searching for that unique flavor in the blended layer. I thought about the process of synthesizing— how we often blend things together to create something new and synergistic. Taking them apart, not to deconstruct, but to isolate, reminded me of the importance of being mindful of individuality, while celebrating commonality.
For me, it was a lesson about so much more than food.

curry cake
mango chutney ice cream