12 Oct 2012

A Nobel trilogy of flavours

By AlphaZeta (Own work) [Public domain],
via Wikimedia Commons
This year's Nobel prize was awarded "for studies of G-protein-coupled receptors". This concludes a marvellous trilogy of Nobel prizes which in sum give us a rather complete picture of how it comes that we are able to sense flavours, that is how we can taste and smell.

Let's for now disregard other senses such as hearing, texture and so forth and consider the flavour of something we eat as being mainly a combination of tasting (tongue) and smelling (nose). This is of course simplistic, but still taste and scent are two of the most important senses involved in our perception of food. If we concentrate on these two senses, which are both so-called chemical senses, we can actually invoke three Nobel prizes to illustrate important parts of this sensing process. They are all very elegantly described in both popular and scientific terms, depending on your background or taste, at the web site of the Nobel prize:

4 Sep 2012

Facts about miracle fruit (miraculin revisited - part 2:2)

Short introduction in Norwegian: I anledning at jeg deltok i en episode om mirakelfrukt på Schrödingers katt på NRK publiserer jeg to blogginnlegg om temaet. Det første innlegget handler om smakstesting av mirakelfrukt. Innlegget nedenfor er del 2 av 2 og er en samling fakta om mirakelfrukt med referanser til forskningslitteratur. Siden denne bloggen normalt er på engelsk fortsetter jeg herved på engelsk.

On the occasion of me attending an episode of the Norwegian popsci TV series "Schrödingers katt" about miracle fruit I post two entries on miracle fruit and its key constituent miraculin. The first post describes a tasting of miracle fruit with a number of sour foods. The second post below is a collection of facts about miracle fruit based on research literature. Part 2:2 below is divided into the following main topics:

9 Apr 2012

New journal Flavo(u)r for researchers and practitioners

A new open access journal for issues related to Molecular gastronomy has recently arrived: Flavour. According to the editors, the journal "seeks to create a shared forum for the publication of evidence-based research in an open access context that will make it accessible not only to researchers but also the wider community of chefs, policy makers and the public". This is no small ambition.


14 Dec 2011

The Kitchen Stories project - Interdisciplinary network of culinary claims

The text below is an attempt at drawing up a new programme/collaboration/network for exploring claims about food and cooking. Hereby, we make an effort to start a new international and interdisciplinary network to explore such claims from various angles. If you are a researcher (from any field), teacher at any level, chef or something else and find this interesting, read on and feel free to contact us. The programme is drawn out by researchers from Finland (here and here) and myself.



Is it true that you mustn't rinse, but rather brush, mushrooms? Should a steak be seared to keep the juices inside? Can you prevent fruit salad from turning brown by sprinkling it with lemon juice? Such apparently mundane questions have been source of inspiration for food geeks at least since “The Curious cook” by Harold McGee (1990) was published, but most likely much earlier. A closer analysis of such questions reveal an abundance of intriguing, surprisingly complex and unexplored questions which might be vehicles for education and even subject for research within natural and social sciences.

The world of food and cooking is full of statements on how to do things and occasionally why one should adhere to these advices. Many are rooted in tradition or are created today by us all and sometimes appear to us like modern urban stories. Some are rooted in long experience of kitchen professionals or home cooks, and some even in science. When tradition and science meet interesting things might happen. In some cases the phenomenon in question (see examples in the introduction) is well described within one field of science but is less so in another discipline, laying questions open for research. Secondly, such culinary claims, which we have termed “Kitchen stories”, provide valuable opportunities in education at various levels (see below). Thirdly, interesting questions might be revealed by laypeople, craftsmen (chefs, artisans) or even school children which in turn could end up as relevant research topics to be studied within various sciences. Finally, such kitchen stories are valuable parts of our cultural heritage and provide rich research material for scientific fields such as cultural history and sociology (see figure).


11 Nov 2011

Enlightening video lecture on argumentation at Penn State University

Twice a semester Pennsylvania State University holds its Ed Waterbury Lecture on science, technology, mathematics, engineering and mathematics education. This autumn, one of my main sources of inspiration concerning argumentation in science was the invited lecturer.

Prof. Sibel Erduran from University of Bristol is a renown researcher, author and lecturer in fields such as science education, argumentation in science education and philosophy of chemistry. Her contribution to a seminar at the University of Oslo a few years ago was the starting point of my interest in argumentation in science education. In fact, this was the main impulse for me getting involved in what we now call "the Kitchen stories project" (see below).

Her 1 hr lecture + Q/A session at Penn State University was on the topic of argumentation in education (mainly middle school) and professional development of teachers, titled "Modeling Epistemic Practices in Teachers' Learning: The case of argumentation". This lecture is available on the university's web pages (open access, hopefully online for a long time).

Sibel Erduran: "Modeling Epistemic Practices in Teachers' Learning: The case of argumentation"


20 Oct 2011

Miraculin revisited - part 1:2

Introduction in Norwegian: I anledning denne ukas episode om mirakelfrukt på Schrödingers katt på NRK publiserer jeg to blogginnlegg om temaet. Det første er en reprise av et tidligere innlegg, dog utvidet med noen flere smakstester. Det påfølgende er en samling fakta om mirakelfrukt med referanser til primærlitteraturen. Siden denne bloggen normalt er på engelsk fortsetter jeg herved på engelsk. Innlegg nr. 1 av 2 følger nedenfor.

On the occasion of me attending this week's episode of the Norwegian popsci TV series "Schrödingers katt" about miracle fruit I'll post two entries on miracle fruit/miraculin. The first is a reposting on a previous entry, expanded with a few more tasting notes. The second post will be a collection of facts about miracle fruit including references to primary literature. Part 1:2 follows below.

The following entry was previously published 7 August 2010, slightly revised.
Note: the original blog entry has some interesting comments worth having a look at.



For some time now, there has been somewhat of a hype about the miraculous berry that makes everything sour taste sweet. Some time ago, I ordered a packet of dried and powdered miracle fruit tablets and gave it a try. The following post gives some background and the results of a truly fascinating experience.

The miracle fruit is a a berry containing the glycoprotein miraculin with the unlikely effect that when your taste buds meet this substance, you taste sour foods as they were sweet. That is, your perception of sourness is altered. In certain parts of the world, the substance has been used for quite long, whereas in USA and Europe it has not yet been cleared for use as additive. The berry in itself is allowed, but unfortunately they don't keep for long and are apparently not suited for shipping fresh. However, a freeze dried version made into tablets does exist and this is the version I tried.


There is quite some amount of research on the effect and mechanism of miraculin on our tongue as a google scholar search for "miraculin" reveals. The first scientific report was in Nature as early as in 1968 (correction: first time published in 1965). There is also research indicating that other plants exhibit similar effects, such as curculin from the Curculigo latifolia plant. The miraculin protein structure shown here is taken from the Swiss protein structure homology-modeling service.*


2 Sep 2011

Food Culture Centre for Children Opened in Oslo


First day of September this year Norway saw a new centre for children's food culture located in an old renaissance farm in the middle of Oslo. This is to be a national resource for helping schools and pre-schools to focus on good food and food culture.

In the Norwegian curriculum the subject home economics ("Food and health") is given throughout primary and lower secondary school. Many would say that this subject does not enjoy much credit of being a "serious" subject in competition with mathematics, language, science etc. There does not even exist school books in this subject for primary school pupils(!) and the subject has not enjoyed the benefits of having its own "national centre for education" to support schools and teachers the same way as many other school subjects (e.g. Norwegian Centre for Science Education).

1 Jul 2011

Norwegian Barista Championships 2011. Part 2c - seminar on profile roasting

In this post I summarise the last seminar I attended at the Norwegian Barista Championships this spring. It was hosted by former world champion barista Tim Wendelboe and focussed on coffee roasting. The following is what I understood from this seminar.


Profile roasting, or roasting profile
As a coffee drinker, I find it interesting to get to know the various roasters' profiles, or roasting personalities so to say. I believe each of the four Norwegian roasters I've gotten to know best have their own rather distinct style. The smallest, Madelynn coffee, have a fairly dark roasting profile resulting in more chocolatey and "brown" aromas with less acidity (and perhaps fruitiness) compared to the other "extreme" among the four of Tim Wendelboe. The coffees from Wendelboe seem to me as extremely clean and rich in acidity, but with slender body. Kaffa roasters, on the other hand, are on the lighter side of roasting but with more full-bodied coffees compared to Wendelboe (some of Kaffa's natural/dry processed coffees are among my all time favourites, I must admit). Finally, Solberg & Hansen being by far the largest speciality coffee roaster in Norway, produces such a wide variety of coffees and roasts that the wide variety might be said to constitute their profile, rather than a specific roasting ideal.

24 Jun 2011

Norwegian Barista Championships 2011. Part 2b - seminar on coffee defects

In this third post from this spring's Norwegian Barista Championships I summarise the most interesting seminar I attended. It was hosted by former world champion barista Tim Wendelboe and focussed on tasting defects in coffee.

I attended two seminars by Tim Wendelboe during this year's event, and of the two the one mentioned here was definitely the most rewarding for me personally.

WORKSHOP/SEMINAR: Flavour defects in coffee
(by Tim Wendelboe)
I always tell my students that if a recipe warn them not to do this or that, they should deliberately try doing it at least once (e.g. don't get egg yolk in the egg whites when whipping meringue, don't open the oven when baking sponge cake etc.). If you don't know how things look or taste when they're failed, it's difficult to have any reference for what's successful. So, go ahead - be disobedient! Tim had indeed done so and collected coffees with various defects in which he brewed cups of defective coffee. The cups were brewed as he would have brewed any other coffee; to the best of one's ability. Not only so, he had also done his best effort to single out the various defects so that we could taste each type of defect separately. Elegant, interesting and very enlightening. The defects we got to taste were:

Faded coffee
(this paragraph has been re-written subsequent to a comment)
at least two reasons for this. The first is past crop vs. new crop. Past crop = coffee that has been stored for some while (e.g. last season's crop) before roasting and sale. This is a typical problem if you are served, say, a Costa Rica coffee this summer because the harvest season is August-December. The second reason for fading is a processing defect if temperature has been too high during drying (e.g. using closed greenhouse-like drying houses with too little airflow). The characteristic of faded coffee is on my palate more subtle and not that critical a defect, but results in lower fruitiness and more woody flavour. The acidity might still be there, but the fruit is more or less gone. So if you get a bag of great Kenya or Panama coffee out of season, don't be surprised if you can't taste all they claim it does on the description on the bag. Also, this defect is easy to get your hands on, even among speciality dealers. Get your hands on a bag of Indian Monsooned Malabar or some Old Brown Java Coffee from Indonesia. These coffees are deliberately aged at the green bean stage to develop a flavour which one would consider being a defect in most other coffee.

Unripe beans
many inexpensive coffees are being uncritically strip picked resulting in a mixture of overripe, unripe and ripe beans; everything is picked at the same time and nothing is thrown away. Characteristic defect flavour would be peanut, old nuts and unpleasant acidity. I would add that unripes also would give a pea-like or grass-like flavour (picture by courtesy of www.coffeeresearch.org).


3 May 2011

Norwegian Barista Championships 2011. Part 2a - the seminars

In this second post I summarise shortly the first three seminars I attended during the Norwegian Barista Championships this year.


As mentioned in the previous post, the championships were not only competitions but also a number of seminars and exhibitions (the full programme is given in part 1). The seminars I attended, and thus am able to give some personal reflections upon are described below and in a following post.

SEMINAR: Extract Mojo – Analysis of coffee extracting using refractometer
This 1.5 hr seminar was given by invited contributor David Walsh working with R&D at Marco beverage systems in Ireland (although their web site is a commercial one they've published quite a lot of educational material such as articles and ppt slides). The presentation was in fact much more than a presentation of the Extract Mojo, and the session was a very clear and systematic presentation of coffee extraction in general. Questions discussed and explained were e.g.