25 Jan 2009

Thorvald Pedersen's recent book: "Molekylær gastronomi"

Thorvald Pedersen has been writing about food and cooking from a scientific perspective for years (mostly in Danish as far as I know), probably well before the term molecular gastronomy gained much attention.

Now he's published his third book on the subject and has dared to use the debated and, according to some, oft misunderstood and misused name Molecular gastronomy. In fact, Pedersen has suggested his own definition of the term, being different from Hervé This' and Harold McGee's:
  • Pedersen: "The science of choosing, preparing and eating good food"
  • This: "The scientific discipline that looks for the mechanisms of culinary transformations and processes, from a chemical and physical point of view"
  • McGee (1 and 2): "The scientific study of deliciousness"
This debate has been running on the MG mailing list also, by the way.

Anyhow, the book has been out for a few months and I got it for present. I've always loved reading Pedersen because he's got this way of making everything warm and cosy, very Danish in a way (Danes seem to be far more relaxed and life-enjoying than us Norwegians, or Swedes for that sake). Reading his books and articles are almost like having one's grandfather telling stories. For that reason, I think Pedersen is even more enjoyable to read than This and McGee language-wise. He seems more relaxed somehow, maybe because he has nothing to prove, being a professor emeritus in chemistry.

The book is shorter than his previous books "Kemikeren i køkkenet" (Chemist in the Kitchen), a collection of his articles in the Danish magazine Dansk Kemi (Danish Chemistry) and "Kemien bag gastronomien" (The Chemistry Behind the Gastronomy) which is more of a textbook in food/cooking science or molecular gastronomy.

"Molekylær gastronomi" is divided based on short articles into two main parts (following the introduction):
  • The preparations. Articles on various foods (not dishes); carrots, potatoes, onions, fish, meat. Each article has one or two recipes, mainly taken from classic(?) cookbooks , exemplifying the main point in the article
  • The meal: starting off with an article on flavour and goes on to describing three meals of increasing complexity, from outdoor cooking during his time as boy scout, to a tasting menu at the fat duck
  • Also, the book is scattered with 27 small boxes on various themes such as plant cell structure, starch, how to identify fresh fish, colours in food, viscosity etc.
In terms of what he writes, most of the results refer to McGee and a few other sources, including his regular food column in Dansk Kemi (the Danish research on gourmet salting for juicy and tender meat is especially interesting, and I've planned to write a post on this). Hence, if you've read McGee, there are not many new astounding discoveries.

One interesting thing is how he uses the tables of nutrients given the various foods. Most commonly people use such tables looking for amount of sugar, fat, whether a food contains gluten etc., that is health purposes. Pedersen however, uses this information for cooking purposes, and he gives the relative amounts of nutrients by dry weight as well. This is really useful, because various foods are easier to compare. One example is looking for amount of starch in different sorts of potatoes, which might have different percentage amount of water. Given values by dry weight makes it much easier to compare (there seems to be something wrong in the potato tables however, as the amount of nutrients add up to more than 100%).

In my opinion, the book is worth buying just for the sheer enjoyment of reading it. Also, I warmly recommend his food column "Kemikeren i køkkenet" in Dansk Kemi, mentioned above, freely downloadable (single pdf files).

11 Jan 2009

Very easy odour adaptation experiment

Matmolekyler published last month an incredibly easy and straightforward experiment for illustrating the phenomenon of odour adaptation.

Adaptation is the phenomenon in which you stop noticing an odour/aroma when you've been subjected to it for a while. This is, amongst other, used as a motive for varying aroma components throughout a meal. Have a look at "Jullovsexperiment: Hacka ditt luktsinne" (Google translated version: "Christmas holiday experiment: Hack your sense of smell"). In this case, Malin Sandström, proposes to use coffee and cinnamon.

I'm on constant search for experiments that give personal experiences with food and science. In my eyes, the sheer ease of this experiment is maybe the greatest advantage, making it very acessable for anyone wanting to experiment with these phenomena.

Heston Blumenthal and Peter Barham have also described this in one of their Kitchen Chemistry episodes (Discovery channel):

"Our brains, it seems, respond much more to changes in which molecules are in the nose and mouth than they do to what is actually there, for example - if you chew a piece of gum, the flavour will disappear after a few minutes, as your brain gets "bored" by the aroma in the nose - but there is virtually no reduction in the amount of flavour molecules in the nose. However, if you simply change the input from your tongue, by, for example - taking a sip of sweetened water - the full flavour will be instantly restored"

Peter Barham (Discovery Channel)

What to teach/learn
  • Gain experience with aroma and sense of smell
  • Experience the phenomenon of adaptation
  • (Experience that flavour experience is both taste and aroma)

I tested the experiment with our students and it worked perfectly! The student with the cinnamon even commented: "the odour fades away while I'm smelling it". Great fun. A colleague has been doing this experiment for several years using (synthetic) almond and rum essences. However, the intensities of these are somewhat uneven, and one swamps the other. Coffee and cinnamon works perfectly :)