Flickr user Katy.Tresedder

I’m going to let the links speak for themselves.

Inspiration

• Ideas in Food has Lobster and Gnocchi on the menu and Strawberry Jam made using a novel technique.
• The Food Canon uses sous vide to prepare Char Siew using pork belly.
• Nordic Food Lab have been doing some pretty interesting stuff with insects.
• Jet City Gastrophysics works through another MCAH recipe: Compressed Melon Terrine.

News

• Check out how Modernist Cuisine is reprsented in the world’s 50 best restaurants.
• Why are more extreme foods creeping onto the menu in America?
• What would it be like to be the food taster for, say, Adolf Hitler?

Science

• IBM Research has begun work on an unnamed cyberchef, an AI system designed to create new dishes specially optimised by its supercomputer-ness. I, for one, welcome our new cyberchef overlords.
• An egg substitute made out of plant matter? See how research is being carried out on this fascinating topic.
• If you can’t wait for the planty egg substitute, Science and Food UCLA have devised a list of easily available substitutes for use in baking.
• ImmusanT are a company researching a cure for Coeliac disease . They aren’t the only company doing so and the race is on as Phase 2b clinical trials are underway to determine if their therapeutics work, and at what doses.

Geeky

• Read how coffee’s influences spread far and wide throughout history.
• A startup wants you to smell like your favourite things, be it paper, whisky or tea. They’re hoping that this will help us think about scents differently.
• Lacking space but have an abundance of money? Take a look at this futuristic kitchen column, which contains not only a fridge, an oven and a cooktop but also a multi-stage water filtration, side-mounted herb garden with UV light, dining surfaces seating up to six, extra storage, AND a solar panel to cut costs.

Only one of these things is ketchup. Which one?

While I was in Norway, I bought a jar of rosehip jam, the spoils of my first round of supermarket roulette.* It was very tasty – bright, slightly acidic, and not quite like anything else – but I had some trouble enjoying it. The problem was that it looked just like ketchup. Intellectually, I knew that it was not ketchup. I knew that it tasted good. I knew that I liked it. But I still recoiled slightly every time I ate it.

This led me to think about how powerful visual perception can be to the experience of taste. It turns out that psychologists, food scientists, and marketers are very interested in this phenomenon, so there’s some improbable and fascinating research out there. A lot of this research focuses on color. One common test is to add fruit flavor and coloring to a drink, mixing and matching the flavor/color combinations. (Drinks work well because they are easy to flavor and color, and lack other cues – such as texture – that influence taste.)

 *Supermarket roulette rules: go to a foreign market, buy something whose label you can’t read, and try it. This can work out very very well – see doce do abobora – or…less well. I do not recommend, for example, Russian Vitamin C-enhanced knock-off tootsie rolls.

Flickr user FUNKYAH

The practical upshot of these tests is that we are surprisingly terrible at identifying flavors when they don’t look like we expect them to. In one study, 26% of people said that a green drink was lime-flavored. It was cherry. When the same cherry-flavored drink was red, nobody thought it was lime.

But this is a pretty sneaky way to do a test, right? We expect that color and flavor should match, and maybe that expectation is so strong that we don’t want to go against it even if the “lime” drink tastes pretty peculiar. But what if the scientists running the tests say, ‘Hey, guys, we’re gonna give you some crazy-colored drinks. The color has nothing whatsoever to do with their flavor.” We’d do better, right?

Wrong. We’re still more accurate at identifying flavors when they come packaged in a color we expect, even when we’re told that color is random.

So why is this?

Flickr user v i p e z

We don’t know. One big unresolved question is how exactly color influences flavor. When taste and color don’t match, do our brains just tend to cast the deciding vote with color? Or does color actually change the way we taste things? The end result is the same – color influences flavor – but in the first case, our brain simply overrides the signals from our taste buds, while in the second, our brain actually changes the way we experience the taste itself. There’s a bit of science out there on how sight and odor interact, but the mechanisms behind the sight / taste interaction seem to be largely unexplored.

And of course, it’s always possible to make new associations. While green ketchup was a giant flop**, the candy and Slurpie purveyors of the world have managed to convince us that raspberries are blue. And as all of us children of the ’80s know, toxic neon green tastes of tangerines.

** Remember green ketchup? Man, that was disgusting.

Left-hand photo: Flickr user yi

Parting quiz: in the opening photo, which is the ketchup and which is the rosehip jam? Tell me what you think in the comments, and I’ll update with the answer in 2 weeks.

Background research:

Spence C, Levitan CA, Shankar MU, & Zampini M (2010) Does food color influence taste and flavor perception in humans? Chemosensory Perception 3: 68 – 84.

Credit to D Sharon Pruitt

The Results from this month’s MOCA are in!  We had a relatively small number of participants, so I will go through everyone’s results individually, but there was a consensus – like the old adage says, presalt your pasta water like the sea for best results!

Setup

We had a mix of pasta types (orecchiette, rigatoni, and rotini), from two brands (Barilla and Prince).  All three experimenters used a tablespoon of salt in the presalted test, as recommended.  In the post-salted test, there was no recommended amount- two experimenters added a “sprinkle” of salt and one added a teaspoon.

Differences in flavor

There were four tasters across the three experiments. All tasters agreed that the post-salted pasta was too salty, an interesting consistency despite the difference in the amount of post-salt added.  One taster could not tell the difference between the unsalted and presalted test. The other three tasters independently described the unsalted pasta as “too bland,” with a clear preference for the presalted pasta.

Differences in Texture

No one thought that there was a difference in texture between the different tests.

Conclusion

The conclusion from our limited testing supports the idea that pasta should be boiled in salted water to improve the flavor.  The same effect clearly could not be achieved by just adding salt post-boil.  This is interesting to compare with our previous MOCA, which also found that the timing of salt greatly affects the flavor of a dish. In other words, all salting is not equal – it seems important to really pay attention to when salt is added to a dish.

I’d like to end with an observation from one of the tasters: Manola also noted that when filling water from a tap, one should use cold water rather than hot water. Hot water has a different mineral composition from passing through the water heater than cold water, and that mineral composition can also effect the flavor of pasta (as well as other dishes, I’m sure).  Sounds like a juicy topic for another MOCA.

Does anyone else know of other tricks or tools for cooking pasta that leads to better results?

flickr user Savannah Lewis

You’ve probably tried this neat taste experiment: hold your nose and chew on a piece of apple.  It tastes sort of like an apple, but kind of indistinct too.  While you’re chewing, let go of your nose. BAM!  APPLE!

But what if you could do the inverse? Can you capture the taste of an apple using smell alone?

We all know what apples smell and taste like. There’s little excitement in smelling apples without being able to bite into one. But what about smells like “granite” or “musk” or “freshly-cut grass”? All these scents are used in perfumery, but it’s impossible to taste them.

Or is it?

Scent: The Dominant Sense

If you’ve followed this blog for a while, you’re probably familiar with the difference between retronasal and orthonasal olfaction. Your nose actually gives food most of its flavor through retronasal olfaction.

For more on olfaction, read Alex Lathbridge’s article, The Olfactory System and Your Sense of Smell

Here’s a quick breakdown:

Smell makes up the majority of what we think of as “flavor”, or as Barb Stuckey puts it:

Flavor = Taste + Olfaction + Mouthfeel

Smell dominates the brain in another way as well.

When input from the eyes, ears, or fingers enter the brain, they queue up at the thalamus, a small brain structure that sits on top of the spinal cord. The thalamus has just one responsibility: direct traffic from the basic senses to other processing centers in the brain. And if the rest of the brain is busy at the moment, the thalamus stops traffic.

The nose doesn’t work that way.

Inputs from the nose’s olfactory receptors fly across the olfactory nerves into a special waystation called the olfactory bulb, which then delivers smells directly to the olfactory cortex, spread across the rest of the brain.

Why does smell work differently from the other senses? It’s not entirely clear. But one effect of the lack of filtering is that smells may be more likely to affect brain function subconsciously. The brain constantly forms long-term memories in the hippocampus and those memories may trigger emotional responses through the amygdala. Smells could be triggering emotional responses in us all the time without us knowing it or being able to filter the effect out.

Can a Smell be Beautiful? Delicious?

To experience the power of scent and memory first hand, I visited the Olfactory Art exhibit at the Museum of Art and Design in New York City, NY.

There, former New York Times scent critic Chandler Burr demonstrates how smell can be an artform.

Visitors are greeted by minimalist displays. Move close to one of the small depressions in the museum’s wall, and a small and ephemeral burst of the scent on exhibit sprays into the air.

Descriptions of each scent fade in and out every minute or so, giving visitors a chance to appreciate the scent by itself first, before reading a professional assessment.

I don’t claim to be an expert in art or smell, but I did take notes on my personal experience with the scents. Here are some of the highlights:

• “I feel like laughing. This is cotton candy, but for grown-ups”
• “Fresh cut grass that transforms into pineapple”
• “This smells like the most complex Rye-whiskey cocktail I can imagine”

Out of the 12 scents available, I would have described two or three as smelling “delicious.” Not that any of the perfumes smelled of food, per se. But these were the scents that somehow triggered a feeling of satiety in my brain, that feeling you get only after eating a meal that has engaged all the senses and you are left feeling spent but victorious.

How to Eat a Smell

While I was writing my book on cocktails, I toyed with the idea of introducing perfume-like aromas into drinks. The idea is little-explored, but growing in popularity.

• This article from the New York Times explores how spice mixes trigger emotional responses.

• In addition to his work at the Museum of Food and Design, Chandler Burr has also designed and executed “scent dinners” in which he pairs complex scents with gourmet meals.

• Mixologist Tony Conigliaro creates Cocktail No.5, a drink that smells like groundbreaking perfume Chanel No. 5

Below is an excerpt from my book, a glossary of sorts that hopefully inspires you to try adding aromas to your creations.

A Glossary of Flavor Additives (and How to Use Them)

Excerpted from Craft Cocktails at Home: Offbeat Techniques, Contemporary Crowd-Pleasers, and Classics Hacked with Science

Bottom line up front: start by experimenting with commercial extracts; move on to food-safe hydrosols if you’re adventurous.

• Extract. Made by infusing botanicals into high-proof alcohol. For example, by steeping vanilla in overproof rum. Commercial extracts can also be made by adding high-proof alcohol to essential oils. Extracts can be added directly to cocktails (drop by drop) or spritzed over the top with an atomizer. Extracts can also be added to spirits to impart unique flavor characteristics (see following section).
• Imitation Extract. Exactly what it sounds like. Also made from high-proof alcohol, but the flavor component is synthetic: either a fragrance oil or a man-made recreation of an essential oil is added to the alcohol.
• Essential Oil. The undiluted aromatic oils of a spice, herb, or other botanical. Extremely difficult to use undiluted. A rough rule of thumb is to dilute one part essential oil in 100 parts high-proof alcohol. In my tests, 1 drop in 1 oz. of 80-proof vodka was about right. Once diluted, you basically have an extract and can use it as you would any other extract.  It is possible to add essential oils directly to large batches of spirits, but I haven’t tried it.
• Fragrance Oil. Similar in composition and strength to essential oils, but whereas essential oils must be the pure distillation of a botanical, fragrance oils are usually synthetic. I think fragrance oils could someday be used to create a completely new gastronomic experience, but they would need to be tested first to ensure they are food-safe.
• Tincture. Basically the same thing as an extract, though “tincture” usually refers specifically to extracts made by combining a botanical with alcohol rather than extracts in which essential oils are added to ethanol. Compared to bitters: bitters are multiple botanicals dissolved in alcohol; tinctures are individual flavors. Some bitters producers develop bitters formulas by combining tinctures one by one.
• Hydrosol. The water-based byproduct of essential oil production. They are significantly less potent than essential oils and carry different aspects of a given flavor. There is no rule of thumb as to how strong each flavor will be. We already use orange flower water and rose petal water in cocktails; many others are available through herb distributors, such are Rose Mountain Herbs.
• Oleoresin. The naturally-occurring mixture of an essential oil into the hydrocarbons of its source plant material. Industrial oleoresins can either be taken directly from plant material or made by combining essential oil with resin. Used frequently in the food industry as a flavor ingredient because they are digestible. I haven’t experimented with these at all because I haven’t found a source online, but they look promising.
• Essence. A term I’ve heard thrown around to describe concentrated flavors, but it has no specific meaning.

Chemicals Not Required

You don’t have to experiment with extracts and oils to emphasize aromas in food and drink. I wanted to create a drink recipe that captures the freshness of ripe berries, but that would be accessible to people who can’t pick their own.

• The key here is cucumber juice because it adds an aromatic grassy note that replaces the freshness lost when using blueberry preserves.
• To make cucumber juice, peel and thinly slice a cucumber, then freeze it and thaw it in a zip-top bag twice. Clear juice will release itself from the flesh through a process called syneresis.
• Orgeat is an almond-flavored syrup that reinforces the nuttiness of blueberries. It also contains orange flower water, an aromatic hydrosol (see above) that once again reinforces freshness.

What smell do you wish you could taste? What smell evokes the strongest emotions in you?

flickr user roboppy

We’ve got plenty of links this week! Check them out after the jump!

Inspiration

• Reclaiming Provincial starts us off with pear-infused honey syrup and the Bee’s Knees
• Marc from No Recipes has a great way to start the day: Eggs Benedict.
• A Carbonated Oba Cocktail comes straight from Molecular Recipes.
• Making use of a nifty rotovap, Ideas In Food have come up with Rhubarb Lillet.
• Molecular Recipes hits us again with Scallops with Dashi that can be made at the table.

News

• Researchers at the University of Warwick have developed a way to reduce the amount of fat needed in chocolate by infusing small amounts of fruit juice.
• Got a bunch of wooden utensils? Do they smell a bit funky? Check out a few methods to correct that and give your wooden tools a new life.

Science

• The UC Davis Food Blog talks about the granulation of honey, common misconceptions and how to avoid waste.
• TIC Gums shows us a way to achieve a uniform texture across granola bars.
• A new paper has been released from Flavour Journal explaining how technology might be integrated with the dining experience in years to come.

Geeky

• Have you ever wondered about the history of doughnuts? I know I have and this explanation on the characteristic hole is a fascinating read.

flickr user MasterTaker

For as long as I can remember, I’ve had what some might call an extremely good metabolism. Whether the result of the genetic lottery or simply a physiological adaptation to my food-filled environment, I’m not entirely sure.

This has had a few benefits – the most obvious being that I can eat quite a lot without suffering any long term impact to the aesthetic appeal of my body. Of course, the negatives have too been plentiful, ranging from my mother – horrified with the amounts I eat – threatening me with de-worming medicine meant for the dog, to the very same parent refusing to make the announcement of dinner, lest I arrive there first and eat what would have been sufficient for four people.

This meant that from a very young age, I was forced to become the osmological equivalent of Daredevil and rely on my sense of smell if I was to be able to have first pick of the food. The myriad of different aromas travelling from the kitchen up into my bedroom had to be perceived, differentiated and acted upon in a short space of time if I was to be able to bound down the stairs and get to the kitchen before being left with only the dregs of the pan.

After three or four failures of what I had prematurely termed my “super-sniffer”, I realised the importance of subtle differentiation in aroma. The sharp tone of caramel could be mistaken for the similar yet far less sweet smell of liver. The low, earthy smells of certain types of fish, when fried, could be easily taken for the herbs and spices used to garnish certain, tastier meats.

Humans, as with many other animals, take learned sensory cues in order to seek out the preferred concentration of nutrients in foods. The sensory reception is believed to trigger anticipatory responses because we learn to associate the sensory characteristics of a food with many of its properties, such as the estimated calorific value post-consumption.

It is these associations which we then psychologically link and allow to influence our expectations about the apparent effect a food will have on appetite, including how filling a food is likely to be (expected satiation) and the extent to which it will stave off hunger until the next meal.

It is all this that runs through the mind of a hungry man walking by a cafe in the middle of the day, the couple sitting in a restaurant deciding which meals they should pick or of a boy in the short window of opportunity that he has to make his mind up whether or not he should launch himself into the kitchen at breakneck speeds.

So how are odours perceived?

The Nose

It would be smart to start with talking about the nose.

Noses come in a wide variety of shapes, sizes and orientations but they all one common factor – the olfactory epithelium.

Taken from Encyclopaedia Brittanica

This small square of tissue sits on the roof of the nasal cavity and is directly responsible for detecting airborne odour molecules known as odourants. It is comprised of three main different cell types:

• Olfactory receptor neurons -  Neurons which congregate to form the olfactory nerve. They are covered with non-motile cilia (suspended in mucus), with the plasma membrane containing odourant-binding proteins acting as the actual olfactory receptors.
• Supporting cells – These act as metabolic and physical support for the olfactory cells, thereby helping them to fully function as part of the olfactory pathway.
• Basal cells – With cells being replaced quite quickly in the body, basal cells act as stem cells capable of division and differentiation into either supporting or olfactory cells. This means that the olfactory epithelium is replaced every 2–4 weeks.

The Bowman’s gland, though not a cell, also plays a vital role in the olfactory epithelium. It delivers a proteinaceous secretion onto the surface of the mucus which the cilia rest in. These secretions trap and dissolve odourants for the cilia to receive and it is this constant flow of secretion which allows old odours to be constantly washed away, therefore preventing odour overload!

GPCRs and The Olfactory Pathway

See the seven-transmembrane helices forming the protein’s necessary shape

The cilia of the sensory neurons are immersed in a layer of mucus. The odourant molecules dissolve in the mucus (thanks to the Bowman’s gland) and bind to receptors on the cilia.  These odourant receptors are but one family of many different types of G-protein-coupled receptors (GPCRs). Some other examples of GPCRs include:

• Taste receptors
• Light receptors – like rhodopsin – in the eye
• GABA receptors in the brain – behaviour/mood regulation
• Receptors for immune system regulation
• Receptors for cell growth regulation
• Receptors for homeostasis regulation

A GPCR is a transmembrane spanning protein which has a G-Protein coupled to it . GPCRs make up a large number of the receptors in the body and are the primary target for many new pharmaceutical products. This is because GPCRs are one of the most important signalling proteins in the human body. In order for cells to function, they have a variety of compartmentalised areas of differing environments which are optimal for the respective functions. This ensures that the environment of a cell – on the whole – is far different from the extracellular environment but through proteins like GPCRs, cells are able to react to changes in the environment thanks to cellular signalling.

GPCR Binding and Signal Cascade

In terms of signalling – a ligand is another word for a molecule which is capable of binding to a receptor in order to garner an appropriate response – part of the cell signalling cascade. The odourants are volatile (easily evaporated) ligands which travel up into the nose to bind to a GPCR.

Now, there are two main hypotheses as to how this binding occurs. The Shape theory states that this binding occurs due to a “lock-and-key” specificity that the odourant. This is similar to the initial theories regarding enzyme-substrate binding but in the case of the olfactory system, it has been supplanted by the Vibration theory. This theory states that the odourant acts more like a “swipe-card”, vibrating with an energy in between the energy levels of the receptor.

Either way, the binding causes a signalling cascade to be instigated – one which results in a massive change in the membrane potential of the cell.

A simple model of the signalling cascade (Taken from MDC-Berlin)

So as the odourant binds to a receptor on the mucus bound cilia, the GPCR changes conformation (shape). This change in shape causes the G protein coupled to the receptor (G_olf) on the cytoplasmic side to activate and is how the signal is passed across the membrane. This, in turn, activates adenylyl cyclase, an enzyme embedded in the plasma membrane of the cilia.

Physiologically, adenylyl cyclase serves the purpose of converting the energy molecule ATP into cyclic AMP (cAMP). It is no different in the olfactory mechanism and ATP is converted into cAMP. cAMP can interact with many different molecules as part of the signalling cascade but in this case, it plays a part in controlling nerve impulses.

One of the functions of the cell membrane is to maintain a voltage difference between the interior and the exterior of the cell. The interior of the cell is filled with negatively charged chloride ions and the exterior of the cell is filled with positively charged sodium and calcium ions. These ions serve the purpose of keeping most of our membranes at a voltage of around -65mV .

cAMP acts as a “second messenger” in that it can then be used to open the gated sodium/calcium channels for the facilitated diffusion of Na⁺ and Ca²⁺ into the cell, which causes the chloride channel to open and release Cl^-. The influx of Na⁺ and Ca²⁺ and the efflux of Cl^-causes a change in the potential across the plasma membrane.

In order to prevent energy being wasted, the cell membrane only fires off a nerve impulse (an action potential) if the potential reaches a threshold amount – 15mV. This is known as the “all-or-nothing” response.

“Why doesn’t the odourant cause the ion channels to open straight away?”

The “second messenger” model is very necessary. For every odourant bound, multiple ATP molecules are converted to cAMP, meaning that the signal given by the odourant binding to the GPCR is amplified. This allows a massive reduction of potential, action potentials to be fired off as a result of low odourant concentrations and the detection of very trace smells.

The action potential is then conducted back along the olfactory nerve to the brain – for it to process this and other olfactory signals reaching it as a particular odour.

Smell Differentiation

With taste perception, there’s a set number of tastant ligands and they each have complementary receptors. Smell is far more complex than that.

Each receptor is capable of binding to several different odourants. To some, this binding is far stronger than with others due to the higher association affinities therein. In turn, each odourant is capable of binding to several different receptors, also with different binding affinities.

This provides the basis for a certain amount of diversity when combinations occur. It works like this:

• odourant A binds to receptors on neurons #1 at 50% affinity, #3 at 75% affinity, and #5 at 100% affinity.
• odourant B binds to receptors on neurons #2 at 75% affinity, #4 at 60% affinity, and #5 at 20% affinity.
• odourant C binds to receptors on neurons #1 with 100% affinity, #3 at 50% affinity and #6 at 75% affinity.

The brain then would interpret the three different patterns of impulses as three completely separate odours. This is the mechanism by which we are able to discriminate between millions of different odourants and have so many different smells in our world. It is one of the most primal ways in which we perceive and understand the world – key for our survival. This all happens in such a small space of time that a blink would miss it.

Or a sneeze.

Throughout the country, there’s a big push to get K-12 students interested in science and math. As part of this, I worked with a small to team at Harvard to create the first Science and Cooking for Kids program in the summer of 2012.  Over two weeks, teams of scientists and chefs taught science lessons and recipes to a group of twenty 5th through 7th grade students.

Graduate student Anna Wang demonstrates the physical properties of whipped cream during the 2012 program.

Although there are already several great resources that use science to teach cooking, such as FoodMaster, The Science and Scientists Behind the Food, and the Science and Food site, I think the Science and Cooking for Kids program can fill a unique role. The collaborations between chefs and scientists give students a direct view into both the recipe development process and modern trends in cooking. I’m working to develop the curriculum for this summer’s version of the program, and my goal is to more strongly show the process of doing science, instead of just demonstrating the concepts. One overall objective is to encourage kids to pursue careers in science or technology, by making it more accessible.

Chef Jason Doo (Kinsai) teaches students about mixtures.

Curriculum

To make the curriculum as broadly applicable as possible, I am using the standards from the Common Core (CCSS) and Next Generation Science Standards (MS) for science and math. Specifically, I’m collecting examples of how cooking can provide tangible, familiar examples of each of these, with a focus on modern culinary techniques that aren’t covered in other lesson plans.

1. Ratios (“CCSS.Math.Content.6.RP.A.3 Use ratio and rate reasoning to solve real-world and mathematical problems”): For a middle-school audience, scaling recipes can be a tangible example of working with ratios. This is especially easy using Baker’s percentages, as described on this Modernist Cuisine post. The trend towards measuring ingredients by mass, in metric units, makes the connection to scientific experiments more direct.
2. Time and temperature (“MS-PS3-3: Apply scientific principles to design, construct, and test a device that either minimizes or maximizes thermal energy transfer.”): Sous vide cooking is a recent development that is perfect for showing the effect of temperature on food, independent of the cooking time, such as those on the Cooking Issues charts. For the complementary view, students can experiment on their own with cooking eggs in simmering water for different lengths of time, to gain a more complete understanding of thermal energy transfer,
3. Chemical reactions (“MS-PS1-2: Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred”): Nutrition is a gateway to talk about the molecules in food. Roasted cauliflower and seared Brussels sprouts are two simple examples of how to turn unpopular vegetables into something more appealing.
4. Natural and synthetic materials (“MS-PS1-3. Gather and make sense of information to describe that synthetic materials come from natural resources and impact society”): Nearly all modernist ingredients, such as agar, lecithin, and xanthan gum, come from natural surfaces. These ingredients are now easily accessible on-line, allowing students to make fruit gels, yogurt spheres, and other creations that were first popularized by Michelin-starred chefs.

Grad student Kate Jensen and Chef Rolando Robledo demonstrate the stability of emulsions.

If there’s enough interest, we would like to run a one-week version for multiple times each summer. This will allow us to test out the new lessons and to develop a curriculum that is more transferable. The current lessons are more about the physical sciences, but future versions could have more about microbiology, botany, or psychology. I’m still looking for more ideas, so I’d love to hear about your own culinary experiments, to see if they could be adapted into lessons for students.

Where do you see science crop up into your own cooking experiences?

flickr user .scarlet

With a new month comes a new Tidbits.

Not to mention a new MOCA challenge! Take part and spread the word!

Inspiration

• Science and Food UCLA drop in the scientific principles behind Ceviche.
• Jet City Gastrophysics step it up with Cheese in a Tube
• Caramelised Carrot Soup is the name of the game at the Food Canon
• Molecular Recipes innovates with a Micro Salad inside a Vanishing Cone.

News

• Check out some of the best April Fool’s Day practical jokes from around the food world. I’m particularly distraught with Google’s, for obvious reasons.
• So the question on everybody’s lips is: Why are more and more people eating guinea pigs?

Science

• MIT students have fun with their Laboratory For Chocolate Science.
• See how tropical fruit is inspiring new research into what we can and can’t eat.
• Molecular Recipes looks at novel ways of introducing miracle berries into a menu.

There’s an old adage for cooking pasta- to cook your pasta correctly, the water you boil the pasta in should taste like the sea. To me, this phrase conjure images of 16th century Italians dipping their cooking pots into the Mediterranean to get water for boiling pasta.  I mean, where else could this phrase have come from?

For those of us not living in the Italian Renaissance, this bit of kitchen wisdom means that we have to pour a ton of salt into our water when we boil pasta.  Why?  ’Cause that’s what our grandmas tell us to do. Or at least, that’s what my grandma always told me. (She told me lot’s of other things too- like how to make pasta sauce).

There would be a few times a year when my mom was allowed to cook the pasta dish for a meal rather than my grandma.  These rare events usually occurred around holidays like Christmas, when my parents would host.  On every such occasion, my grandma would take one bite of the pasta, and say to my mom “Non ti sale l’acqua” (You didn’t salt the water).  And my mom would say “Yes I did!”  And my grandma would say “Not enough.”

And so it was etched in my head that I would never undersalt my pasta like my mother, for fear of the disapproval of my very Italian grandma.  Of course I never actually cooked pasta for my grandma, but the lesson was there seared into my brain, like an 11th commandment.

So we get to the topic of this month’s MOCA: Does pre-salting the water improve the taste of pasta? For most of my life, I’ve been afraid to do anything but salt the water, and I am sure that salt does improve the flavor, if not the texture.  So we decided to put a little ScienceFare spin on the question: What if we just post-salt the pasta after boiling?  Does presalting the water before cooking pasta do something that simply salting the pasta post-boiling won’t do on its own?

Thus, we have a three-part MOCA challenge for you pasta-lovers.  We want you to make pasta three ways, unsalted, presalted, and post-salted. Make, eat, and tell us if there’s a difference!

Here are your steps:

1. Fill two pots with water and bring to a boil.
2. Salt one of the pots once it starts to boil.  The rule of thumb is one tablespoon of salt for every gallon of water, which is probably about the amount of water you’d put into a big pot.
3. Take a pound of pasta, and put half in one pot, half in the other, and boil ’til your desired consistency is reached.
4. Drain the pasta from both pots.  Split the unsalted pasta into two batches, and add a little bit of salt to one batch to taste.  I’m not really sure what amount is appropriate here, something in the 1/8-1 tsp range is probably about right.
5. You should have three batches of pasta now, one big batch of presalted pasta, a small batch of unsalted pasta, and a small batch of post-salted pasta.
6. And, taste! If you can, recruit one or two spouses/friends/children as blind taste testers. After tasting, fill out your observations in this form.
7. Optional bonus points: keep the pasta separate when you add the sauce, and see if you can still detect a difference between the three batches through the pasta sauce.

As usual, if you take any pictures, send them to us at cookingeditor@iridescentlearning.org, and we’ll use them in our writeup.

The deadline for submitting and having your results count for this MOCA is April 24th, with a summary post following the week after on May 1st.  Any questions, post a comment here or shoot us an email at cookingeditor@iridescentlearning.org. Happy April MOCAing!

Flickr user sherylsheryl

Imagine slurping down raw Chinook salmon, cool and unctuous. The taste is sharp and clean and unmistakably savory, with a bit of mouth-filling fattiness. The fish is so fresh, it’s practically still thrashing.

Oh, wait, it is still thrashing. And you’re gulping it down whole, crunchy with bones and slick with fish skin. And maybe you can’t really taste it at all, even if you did chew. Slightly less appealing than in the first sentence, yes? Minimalist sushi is always on the menu for sea lions, dolphins, and other marine mammals, and knowing how they (and other carnivores) experience food tells us something about how the process of taste has evolved over millennia.

How taste works*

Three of the five basic tastes – sweet, umami, and bitter – are sensed via specialized proteins in taste bud cells, called receptors. These receptors act as telephone lines between your mouth and your nerves, picking up molecules of food and sending tiny messages to your brain. There are several different kinds of these receptors, each with its own message: “sweet!”, “bitter!”, “umami!”. In turn, each of these receptor proteins is encoded by a gene or two, strings of DNA that provide the blueprints for a working sense of taste.

*Okay, how 60% of taste works, but that was less catchy. Salty and sour work differently and aren’t part of this particular story.

Flickr user Katy Silberger

How to tell what a sea lion tastes

We know what a functional gene looks like, so we can look for species whose taste receptor genes are busted. Genes can be a use-it-or-lose it proposition. Think about photocopying a picture, and then photocopying the copy, and then photocopying that copy, over and over and over and over, times millions of years. If no one is looking at the copies to make sure they came out right, you’ll probably end up with a blurry disaster. DNA is like that, too.

Last year, two groups of scientists sequenced the genes for sweet, umami, and bitter receptors in bestiary’s worth of carnivores. They were interested in knowing which species had functional genes, and which didn’t. Not just for dinner-party trivia* – tracking the busted genes on a family tree helps us see patterns in the evolution of taste.

*For your next dinner party: cats can’t taste sweetness, but dogs can. Make of this what you will.

Roman floor mosaic of a dolphin eating a squid, Flickr user level 5 vegan

So, what do sea lions taste?

Very little, as far as we can tell. One of the most interesting patterna to fall out of both studies was that marine mammals seem entirely to lack working proteins for sweet and umami, and probably bitter. Sea lions, fur seals, harbor seals, and dolphins all lack sweet receptors. Six species of seals and sea lions don’t have functional umami receptors. Dolphins also lack working bitter receptors. This tracks with limited studies showing that dolphins and sea lions have very few taste buds, and that they don’t seem to react to sweet and bitter tastes (umami hasn’t been tested).

So why do these marine mammals seem to have a very limited sense of taste, despite having evolved from (presumably tasting) forebears*? They’re carnivores, which might explain the loss of sweet receptors – there’s evidence that many different groups of animals have lost the ability to taste sweetness as they adapt to a completely meaty diet. After all, sugar isn’t a major component of raw fish and meat.

But seals, sea lions, and dolphins have lost their ability to taste umami, too, and this is a huge component of a “meaty”, savory taste. Maybe it’s because they swallow their food whole, and what’s the point of taste buds if there isn’t much to taste? Maybe because they live in the sea, and saltiness interferes with the taste of umami. Maybe because fish and squids, their main foods, actually don’t have much umami taste when they’re ultra-fresh – the umami-boosting compound in fish builds up only as fish starts to get old and, well, fishy. But whatever the specific reasons, it seems very likely that diet played a major role.

*Also for that dinner party: giant pandas can’t taste umami, but polar bears can.

Flickr user ND Strupler

Why do we care what sea lions taste?*

These studies are exciting because they link loss of taste with different diets. Eat anything that stands still long enough, like people do, and your tastebuds will probably remain pretty diverse. But if you evolve to eat only meat? You’re not really using your sweet receptors, so you’ll probably lose them. Evolve to live in the sea and swallow your fresh fish whole? Kiss your umami and bitter receptors goodbye, too. The research on marine mammals is especially compelling because dolphins and sea lions show the same kinds of taste loss, even though they have very different ancestors. The fact that both of these groups independently lost the same tastes provides pretty good evidence that the loss is truly related to their very similar diets, and not just to historical vicissitudes**.

So next time you bite into a juicy burger or a perfect gem of sushi, appreciate it. Some of your distant evolutionary cousins can’t.

*Aside from the obvious reason: because it’s awesome.

**If all the animals with the same taste loss had the same common ancestor, it would make a lot of sense that taste was lost just once in that ancestor, and then passed on to its daughter species. Which could be related to diet, but could also be related to any number of things going on with that common ancestor.

Note: I’m thinking of writing short posts like this on a semi-regular basis – summaries of particularly cool papers having to do with the intersection of genetics and food/taste. What do you think?

The sources:

Sato JJ & Wolsan M (2012) Loss or major reduction of umami taste sensation in pinnipeds . Naturwissenschaften 99: 655–659

Jiang P, Josue J, Lia X, Glaserb D, Lia W, Brand JG, Margolskee RF, Reed DR & Beauchamp GK (2012) Major taste loss in carnivorous mammals . Proceedings of the National Academy of Sciences 109 (13): 4956–4961