A couple of books have caught my eye during the year and have naturally made their way into my Christmas wish list (and some I’ve already ordered myself). Please let me know if there are books you belive should be on this list that I have missed.

Culinary Reactions: The Everyday Chemistry of Cooking
by Simon Quellen Field
288 pages

The back cover states “When you’re cooking, you’re a chemist!”. I couldn’t agree more and figured this was a book for me. I already have my copy in front of me and see there are many interesting observations and experiments described.

Heston Blumenthal at Home
by Heston Blumenthal
408 pages

The Family Meal: Home Cooking with Ferran Adria
by Ferran Adrià
384 pages

Ferran and Heston have jumped onto the cooking-at-home-with-great-chefs waggon. They’d be more than welcome to come and cook in my kitchen, but until that happens I’ll let their books inspire me. An important thing about these books is that, given their close collaboration with scientists, I have a high expectation that the advice given in all recipes should be scientifically sound (which of course is not the case for many other cook books).

Neurogastronomy: How the Brain Creates Flavor and Why It Matters
by Gordon M. Shepherd
288 pages

I stumbled across this one by chance. It looks like a “must have” too me, and my copy is already on its way. In an interview with Salon, the author Gordon M. Shepherd, a professor of neurobiology at the Yale School of Medicine, says that:
“I began to realize that increasingly smell was for sensing the flavor of food. It goes almost unrecognized as we eat our food because we think it all comes from taste in our mouths. The more research that I did on flavor, the more I realized that the sense of smell was the dominant sense in flavor — and that we are almost totally unaware of it.”

The Oxford Companion to Beer
edited by Garrett Oliver
960 pages

Having ventured into brewing I found this book quite irresistable!

The Kitchen as Laboratory: Reflections on the Science of Food and Cooking
edited by Cesar Vega, Job Ubbink and Erik van der Linden
336 pages

I’ve mentioned this book previously. With 35 essays covering a range of topics this should be of interest to many Khymos readers!

Apart from these books we just have to face it: there’s no way around Modernist cuisine. If you don’t own a copy yet I’m quite sure it still sits there on the top of your wish list. And – if you happen to read Swedish – I would highly recommend the recently published book Matmolekyler (“Food molecules”) by Malin Sandström and Lisa Förare Winbladh (also check out their blog blog with the same name – also in Swedish).

It came as no big surprise that NOMA defended its no. 1 position in April. A lot of the press coverage of NOMA and René Redzepi focuses on foraging (some even claim that we are in The Era of the ‘I Foraged With René Redzepi Piece’). It is all about nature and natural ingredients. Many would probably claim that NOMA is as far away from molecular gastronomy and science as you could possibly come. In March René Redzepi attended The Flemish Primitives in Oostende. I was there, and the one question I asked René at the press conference was this:

ML: The Flemish Primitives aims to bring together chefs, scientists and artists. There is also a co-operation between Noma and the University of Copenhagen. What have you learnt from from working with scientists?

RR: A lot! A lot! There is an incredible amount of knowledge to be gathered. Chefs are caretakers of flavor whereas scientists care about why things happen. But they don’t care about flavor. Torsten Vildgaard, one of my chefs, has been working 4 months every year on the project at Copenhagen University.

In a recent interview with WSJ René also said that “a lot of the techniques developed during the molecular phase have now been incorporated even into our style of cuisine because of their practicality”. I find it very fascinating and reassuring that René sees no contradiction between a modern approach to cooking, utilizing science and technology for what it’s worth, on the one side and his own cooking on the other. He is truly open minded and lets modern equipment and techniques coexist with his foraging approach.

During the interview René also mentioned the Nordic food lab, a non-profit organization founded by René Redzepi and Claus Meyer that aims to scientifically explore the New Nordic Cuisine (manifesto, 40-page booklet). They promote open sharing of their results, and contrary to food research in universities the Nordic food lab is “committed to show tangible results on a more frequent basis and on a slightly lower academic level than would be expected from e.g. a university.” I really recommend checking out their news section (which is more or less in a blog format – unfortunately I could find any funtioning RSS link on the page, but http://www.nordicfoodlab.com/feed seems to work!)

Of course René also talked about other stuff than food science and molecular gastronomy. One thing that he’s particularily focused on now is the new food festival MAD foodcamp (MAD is “food” in Danish). It takes place on August 27 & 28 (the last two days of the Copenhagen Cooking festival). The topic this year will be vegetation, there will of course be chef & food, but there is also an International symposium and they have announced that Harold McGee is coming! René mentioned that the most challenging part is in fact to find writers and scientists who want to contribute to the symposium.

A little more than a week ago Dave Arnold posted a great, new technique: pressure infusion using a conventional iSi whipper! Just think of it – the whipper has been around for decades, and years a go Ferran Adrià pioneered it’s use for espumas. Several have suggested it’s use for carbonation of fruit. But no one had thought of utilizing the whipper for infusions – until August 11th when Dave Arnold of Cooking issues posted the results of his experiments in “Infusion Profusion: Game-Changing Fast ‘N Cheap Technique”. The first blogger to pick up the technique and post about it on August 12th was Linda of playing with fire and water who termed it a revolutionary technique. A couple of days later, on August 17th Aki and Alex of Ideas in food posted a combined pressurized infusion of basil and marination of mozzarella. And then on August 20th James of Jim Seven describes his results comparing conventional cold brewed coffee to cold pressure brewed coffee. It’s really fascinating how fast the idea spread, and it illustrates the benefits of an open and sharing approach to food innovations.

The science behind this is quite simple: in the pressurized canister nitrous oxide (N₂O) dissolves and penetrates the food. When the pressures is suddently released (and it is important to release pressure as fast as possible) the sudden pressure drop causes the dissolved gas to nucleate and form bubbles which expand and disrupt cells, thereby releasing flavor compounds. The physical phenomenon is known as cavitation.

A single N₂O charger contains 8 g of gas corresponding to 0.1818 moles or a volume of 4.1 L at 25 °C and 1 atm pressure. The volume of the chargers is 0.01 L which gives an impressive initial pressure in the chargers of 445 atm! With an approximate volume of 0.7 L the pressure in an empty whipper charged with a single charge would be nearly 6 atm. When liquids are added the volume decreases, but the effect on the head pressure will depend on the type of liquid added. The solubility of N₂O in water is 0.15 g/100 mL at 15 °C, meaning that with 100 mL of water, the head pressure would be roughly 10% higher than in an empty canister (that is, if the solubility is independent of pressure – I’m not quite sure about this). However, since N₂O is a rather non-polar molecule the solubility in ethanol or even oils is much greater than in water, with a resulting lower head pressure. But since flavor delivery is mediated by the dissolved gas suddenly nucleating and bursting cell structures, infusions using ethanol or oil will actually be more effective than those with water because more gas can be dissolved in these solvents (besides the fact that ethanol and oil are better solvents for flavors than water).

Thinking about how I could utilize the pressure infusion technique I came to think about the problems I ran into with hay like off flavors in the parsley and banana flavored marshmallows I made for TGRWT #2. The off flavors can be traced back to 3-methyl-2,4-nonanedione which likely stems from oxidation of unsaturated fatty acids or polyenes. Crushing parsley inevitably leads to oxidation (possibly also enhanced by mixing intra and extra cellular comounds/enzymes), but with pressure infusion – practically in the absence of air – seems to be much gentler than crushing according to Dave’s initial report (as judged by color). So I did a quick experiment with this, infusing a couple of sprigs in 2 dL of water for about 2 minutes. This was by no means enough, and the water had only a faint aroma of parsley (vodka would of course have been much better for the flavor extraction). But it was a clean parsley aroma, and the water was perfectly clear.

The Canadian sommerlier François Chartier (he has an extensive website featuring several blogs, including a section named Sommellerie moléculaire) is out with a new book on food and wine pairing. It’s not just another (superfluous) book on the subject. As the title Papilles et molécules (= Tastebuds and Molecules, unfortunately not available in English) suggests there is some science involved. It turns out in fact that he has applied the principles of flavor pairing to food and wine. With help from Richard Béliveau from Agriculture and Agri-Food Canada and Martin Loignon from PerkinElmer he has analyzed wines and food and comes up with the following suggestions for lamb, as described in the article “Chemistry-set wine pairing”:

Having roast lamb? Don’t waste it on an ill-advised red Bordeaux, the old standby trotted out by generations of sommeliers. Lamb’s characteristic flavour comes from thymol, an aromatic compound found in the oil of, yes, thyme. It’s also a flavour note associated with red wines from the southern Languedoc region of France, such as Minervois, Corbières or St. Chinian.

Other combinations mentioned in the article include:

rosemary – white wines from northern Alsace
pork – oaked red wines
curries – viognier
cinnamon – pinot noir, grenache, ice cider, oloroso sherry

François Chartier also introduces “bridge ingredients”. Mint, which goes well with sauvignon blanc, shares aroma compounds with parsley, fennel and tarragon. Based on this he theorizes that sauvignon blanc should also pair well with dishes based on these ingredients.

As far as I can see (with my very limited high school French) there are no links or references to all the other activities in the field: Heston Blumenthal’s pioneering of the concept together with François Benzi from Firmenich, the Food pairing website – not even to the TGRWT food blogging event Nevertheless it’s nice to see that the concept has now been applied to food and wine as well. As I don’t own the book yet I can’t tell whether François Chartier includes odor activity values in his discussion or not (but I certainly hope he does!).

Update: The book is now available in English as Taste Buds and Molecules: The Art and Science of Food With Wine.

Inspired by the Swedish bread blog Pain de Martin which I recently discovered I decided it was time to have a go at sourdough breads! Although one of my favorite types of bread it’s a long time since I gave it a try and even longer since I actually succeeded. Leaving apple peel covered with water for two weeks in a cool place (15 °C) I got a light apple cider which I used to make a starter some years ago. I followed a recipe from the Norwegian artisan bakery Åpent bakeri and it gave a marvelous bread. But since then I’ve tried to repeat this twice without success. No wonder that even Rose Levy Beranbaum in her book “The Bread Bible” writes that she didn’t intend to include a chapter on sourdough at all. There’s no doubt that sourdoughs are tricky, but I was a litte surprised and disappointed that someone who sets of to write a 600+ page book on bread even considered to skip sourdough… Luckily she changed her mind and the introduction has a fascinating nice-to-know fact: 1 g flour contains about 320 lactic acid bacteria and 13000 yeast cells!

I believe one the reasons why sourdoughs seem to live their own lifes sometimes is that they need to be kept in a warm place. My kitchen isn’t that warm so I figured it was time to use my immersion circulator and give sourdough another chance (who says you can only use immersion circulators for sous vide anyway? – I think my next project will be to make yoghurt!). With a thermostated water bath keeping a sourdough starter at constant temperature is as easy as 1-2-3. But surprisingly I haven’t seen any blogposts yet from people using their sous vide water baths for sourdough starters (although some have built their own water baths for this purpose using aquarium equipment).


Fresh apple peel in water. This particular experiment failed – the cider smelled OK, but there was quite a lot of mould on the surface after two weeks so I didn’t dare to proceed …

It was Martin’s post on an apricot starter that triggered my desire for sourdough (but careful – never close your jar with a rubber as shown in his picture!). I got a bag of dried apricots and gave it a try. There was some bubbling and it smelled quite nice, but the bread dough never rose properly. I later found out that in a comment to the first post and a later post on the same topic it was pointed out that the apricots should not be treated with sulfur dioxide or a sulfite (used to conserve the fruit, appears on labels as E220-228 in Europe). That’s very obvious once you think about it, because the sulfur dioxide/sulfite is there to kill microogranisms and increase shelf life. For a sourdough however you want living microorganisms! The solution to this is to use untreated dried apricots. I haven’t been able to find any yet, but I’ll definitely give it a new try once I find some! Other options of course are to use dried or fresh apples, pears, grapes – preferably not treated with pesticides or sulfur dioxide – as the surface of these fruits are host to many yeasts.

A relatively firm rye starter with 150 g water and 200 g whole grain rye flour (left) shows signs of yeast activity after 24h at 28 °C (right).

Having failed with the apricot starter I decided to give a traditional rye sourdough a try, using a recipe from the book “Brød” (=bread) by “Åpent bakeri”. I got a nice bubbling after 1 day, but the starter was pretty dry. As I discarded a portion and fed more flour and water to the starter it seemd as if it died… I (believe) I followed the recipe very accurately (except for the very first day where I opted for a hydration of 75% instead of 60%), but the final dough never rose, so I had to cheat and add bakers yeast in order to actually get the breads baked. Acid production was fine however and the resulting flavor was very delicious and I got the crumb that I desired! However, with all these problems I figured it was time to turn to the scientific litterature and read more on sourdouhs … More on what I found out in a follow up post.

One last thing: Despite my limited experience with sourdoughs I’ve already been a little annoyed by recipes for starters that require one to discard a significant portion of the sourdough every day before feeding the start with more water and flour. One obvious way around would be to start at a much smaller scale so that every feeding can be done without having to waste any sourdough. In fact Kurt Janz already has a post with detailed instructions on a less wasteful sourdough (and he BTW has one of the most comprehensive sites on sourdough I’m aware of including a sourdough calculator). The only reason I could think of why one perhaps would want to use more than a couple grams of flour to start with would be to outnumber any unwanted yeasts or bacteria from the air or the equipment. Is this the case? Are there any other reasons? To circumvent this one would simple have to work very clean and wash all equipment properly.

Just a quick note to point you to the new blog “Cooking issues” featuring Dave Arnold and Nils Norén from the French Culinary Institute. In addition to posts inspired by ongoing activities at the FCI they have a comprehensive primer on the use of rotavaps in the kitchen (including several recipe suggestions!). Highly recommended!