“Not bad, it tastes like beer, I could drink this.”
So it has a pretty good taste. It tastes like a light version of what we were trying to achieved (a brown ale). Considering the alcohol content is probably around 3%, we can probably sell it off (not that we’re selling) as a “light dark beer.” If it would have been a little bit more alcoholic, it would probably taste a bit stronger and more flavorful, but for a first try, it is really nice!
And it pours pretty nicely too, look at that head!
What would we do differently next time? It is likely that during the boiling phase, we didn’t extract enough of the sugar. The recipe we were using, did not use the “tea bag” technique as we were. So perhaps boiling for a bit longer would have extracted more sugars, giving the yeast more stuff to ferment.
“Pretty tasty, good for a first try, and plenty of room to improve! We did it.”
There’s a molecule called miraculin and as the name suggests, it’s quite miraculous. The molecule is a glycoprotein, meaning it has both amino acids (the building blocks of proteins) and oligosaccharides (sugars). It’s extracted from the fruit of the Synsepalum dulcificum plant, which is native to West Africa.
Even though the molecule is part-sugar, it does not taste sweet. But it does something funky with your taste buds: if you eat a miracle berry and thus expose your tongue to miraculin, the molecule binds to the sweetness receptors. If you then eat something sour, it will taste sweet instead.
The exact mechanism is still unknown, but the molecule changes your taste perception by ensuring sweetness receptors are activated by acids. For about an hour, sour-tasting foods are weirdly sweet.
Now you can buy a “strip” of miracle berry pills, which comes with a ticket for a “flavor trip” and looks a little bit like drugs.
Putting the miracle to the test
Guess what we did? Of course, we put it to the test!
As promised, everything sour tasted sweet! Here’s an overview of what we tried:
Balsamic vinegar already has some sweetness to it, but with miraculin there was nothing sour to taste. Even though my mouth was still reacting to the acid, I could not taste it! On another occasion, I had also tasted white vinegar, which really burned my tongue even though it didn’t taste sour.
The citrus fruits all tasted like a very sweet orange! Almost unbearably sweet, to be honest. Lemon juice (the kind that comes in a bottle) tasted like a lemon candy: a little sour but with enough sweetness to easily take a shot.
The Granny Smith apple slices tasted like a non-Granny-Smith apple, as you might expect.
Strawberries tasted like you’ve put some extra sugar on them, which I can tell you is quite delicious. Even more delicious: a strawberry with some cream cheese. Instant strawberry cheesecake! And a strawberry with sour cream that tastes just like whipped cream? Yum!
The tomato wasn’t really that special.
A kiwi tasted like a golden kiwi, which already tastes softer and sweeter than a green kiwi. Makes total sense.
Bitter flavors are also changed. For example, tonic water tastes pretty much like Sprite. And grapefruit tastes sweet, though you can still “feel” the bitterness.
Finally, spicy things change in taste too. A nibble from a chili pepper made my mouth burn but without tasting the burn. Weird.
It was a very interesting experience, or flavor trip if you will. But as a fan of sour – I always eat the slice of lime or lemon in my drink – I prefer the world being a little less sweet.
Because you made it to the end, here’s a bonus: a stupid picture of me eating a very sweet-tasting lemon!
Our fermentation vessel has been sitting at room temperature (~ 20°C or 68F) for two weeks.
It’s time to move some things around. Or move some liquid into some bottles, to be more precise.
In the bottles, we want some final fermentation to happen. This won’t really add any alcohol, but CO2. Perfect to create a bubbly beer! But there is one problem: all the sugar we put in the wort has been eaten up by the yeast in the fermentor.
So we have to add just enough sugar for the yeasts to convert to CO2 gas, but not too much (we don’t want the bottles to explode). We made up a sugar-water solution by boiling 2 cups (473 mL) and dissolving 4 oz (113 g) of sugar, which we mixed into the fermented almost-beer. We also needed to move the almost-beer into our bottling bucket – carefully, as to not add too much oxygen or contaminants!
Next step was to set up a bottling assembly line. Part one: filling the bottles up, leaving about an inch (2.5 cm) at the top.
Part 2: capping the bottle.
And there we are: a bottle of our very own, home-made beer!
About 40 bottles, actually.
Okay, we’re not quite ready. We need to give the yeast another week or two for the final fermentation. After a quick taste of the almost-beer, I kind of hope those two weeks will change the taste (and the bubbliness) because for now, it tasted quite bland.
In addition, our special gravity measurement – which gives an indication of sugar content and can be used to estimate the alcohol content by comparing with the original value – wasn’t very promising. Our beer seems to be less than 3%.
But we’re not giving up hope yet! In two weeks, we’ll see what the final product is. I’ve also read that a few weeks of extra “ripening” can help with the taste as well. And we can always give brewing another go, keeping in mind what we’ve learned so far.
While we’re waiting for the yeast to do its thing, it may be useful to learn about what exactly fermentation is. Fermentation. You’ve heard it before, in the context of beer or kimchi or sourdough bread (or in a biochemistry class). But what does it mean? And why isn’t yogurt alcoholic?
Briefly, fermentation is a biochemical process where tiny organisms break down a complex molecule, such as starches or sugars, into a simpler molecule, an acid or an alcohol, while making some energy. This happens in an anaerobic environment – meaning it does not require oxygen. This contrary to aerobic processes, like what we humans do most of the time when we want to convert sugars into energy.*
Yeasts and bacteria are the two types of organisms that do this sugar breakdown. There are three different types of fermentation, depending on the end product.
In a lot of cooking, we use lactic acid fermentation. In this case, the yeast or bacteria convert starches or sugars into lactic acid. Think kimchi, sauerkraut or pickles, but also yogurt and sourdough bread.
To make alcohol, however, you want to be aiming for ethyl alcohol fermentation. The sugars get converted into ethanol (the alcohol part) and CO2 (the bubbly part). Bakers yeast is also an ethyl alcohol fermenter: there is no real ethanol left in your final bread, but the CO2 production is what helped your dough to rise.
Finally, there is acetic acid fermentation. In this type of fermentation, sugars from grains or fruit are converted into acids. This is what makes vinegar.
Certain microorganisms are better at certain types of fermentation. That is why it is very crucial that the wort does not get contaminated by outside yeasts or bacteria: you only want the alcohol-making types, not the acid-making types. Unless you want to make a sour, that is.
It is also why, to make a sourdough starter, you just leave some sugars (starches actually to be more precise, in the form of some flower in water) out on the counter. The bacteria and yeasts floating around in the air are the ones you want for lactic acid fermentation – and to start up a sourdough culture.
Controlling the rate of fermentation and end products is a balance between making sure you have the right microorganisms (not all yeasts like being in alcohol – let alone making alcohol), balancing the water and sugars (is there enough food?), controlling the temperature (we prefer certain temperature, so to microorganisms) and waiting the right amount of time. That’s why fermentation is a bit of a science and also a bit of cooking. Though science and cooking are actually very similar to start with.
So to recap, fermentation is a process where yeasts and bacteria convert starches and sugars into alcohol and/or acids, with some by-products. And yogurt isn’t alcoholic because the milk-loving bacteria are lactic acid fermenters, not alcohol fermenters.
Beer update: checking in one day later
Disaster has struck. We left the fermenter for one day and came back to this mess:
We had filled up the container too much, so once the yeast started munching away at the sugars, the extra build-up of foam caused the stop to come off. Oh no.
So we needed to clean up. We also siphoned out some of the liquid to avoid this from happening again. Hopefully, we did not expose the beer to external oxygen and yeasts and all during this process…
We put the S-stop back on the fermenter. This ensures that no gasses can come in, while gasses can go out. During fermentation, glucose (which is sugar) gets converted into alcohol and CO2. The latter is a gas and needs to go somewhere, so we let it go out.
This was last Monday. Since then, there seems to have been very little activity in the fermenter. The good news is that everything smells quite nice and beer-ferment-like, not sour, so we will move to STEP 7 sometime in the next few days: bottling!
*I say most of the time because when we get muscle cramps, this is because we’ve been working too hard without providing our cells with enough oxygen to do aerobic respiration (the oxygen-needing-kind). In that case, our cells go into anaerobic respiration, which is very similar to fermentation actually. The result of anaerobic respiration is lactic acid (hey – go back and read about how that’s one type of end product for fermentation!) and some quick energy for your cells to use in the form of ATP. Anaerobic respiration is less efficient than the aerobic kind, but it can get us some quick energy in a pinch.
Source for little factoid is that one episode of the Magic School Bus that I remember where Ms. Frizzle was doing a triathlon and her muscles started producing lactic acid so the students – who were obviously in a mini school bus inside Ms. Frizzle (where else?) – let out the air of the tires so her muscles would have oxygen.
Last weekend, we started brewing. Not ideas (though we have a ton of those), but beer. As this is a first for me, I decided to document the process so I can learn from the likely many mistakes we’ll very definitely be making. And learning some beer science along the way. There are worse things.
Step 1: The Prep
I cheated a little bit here… My brewing partner-in-crime had done most of the preparation beforehand – like buying the grains and all the kit for home-brewing. We biked out to a home brew shop to get the grain milled and buy the last bits of supply, most notably the yeast.
With our newly ground grain (apparently this is called grist and it smelled deliciously sweet), we biked back home and started cleaning everything. Beer is a product of fermentation: yeasts break down the sugars in the grain and turn them into alcohol. To get a good tasting beer, you want to make sure that only the beer-making-yeast is doing the fermenting and that all other types of yeast and bacteria are far, far away from your beer.
Hence, we cleaned and sanitized all the equipment. Thoroughly. And then again.
Step 2: Making the mash
Did you know that beer is basically just fermented grain-tea? Not that different from Kombucha tea actually – just not associated with a current health craze. The first step to making beer is soaking the grist in hot water to extract all the sugars that will be later fermented. This is called mashing.
We set up the boiling pot outside, ready for curious onlookers to wonder what we were cooking up.
We filled the pot with about 30 L (7.3 gal) of water and heated it up to ~ 75°C (~ 170F). We didn’t want the water to boil, like with green tea, if the water is too hot you get a lot of bitter tastes and we want all the sweet sugars to seep out. In this pot, we then dunked a giant teabag filled with the grist (~ 4 kg/ 9.25 lb of the stuff).
After an hour, our tea was ready. A little taste confirmed that we had made grain tea – more correctly known as wort. A little squeeze of the bag, and out it went. We added a little bit of brown sugar (170 g / 0.375 lb), just to make sure there’d be enough sweet stuff for the yeast to eat. [I initially wrote “yeat to yeat”. Help.]
We then measured the specific gravity of the wort. This would give us an indication of how much sugar (more sugar = higher specific gravity) we were starting out with, important to figure out how alcoholic the end result will be.
We were ready for the next step.
Step 3: Hopping the wort
On paper, beer is quite simple. You have water, grain, yeast, and hops. Mix them together in the right way, and you get beer!
The next step in our process was adding the hops – without a bit of a hoppy flavor, no beer! We heated up our water to a boil (> 100°C / 212 F) reused the tea-bag-thing, filled it with our first type of hop (12.5 g / 0.44 oz of Northern Brewer). After 45 minutes of simmering, we added the second type of hop (28 g or 1 oz of Fuggles – who names these things?) and Whirlfloc, which is a tablet containing Irish Moss and Kappa Carrageenan and makes sure your beer doesn’t get too hazy.
15 minutes more of boiling and we removed the bag, and got ready for cooling. A quick taste of the liquid proved that it already sort of tastes like beer. There’s some sweetness, some hoppiness, some bitterness but it’s also flat and lukewarm. British Ale much?
Step 4: Cooling
Yeast works best at a certain temperature. Too cold and the metabolism slows down, leading to less efficient sugar-to-alcohol conversion. Too hot and the yeast just sort of dies.
To cool the wort to a yeastly comfortable temperature of 25°C (or 77F), we put an immersion chiller into the pot. An immersion chiller is a coil of copper tubes, through which we ran cold water. It took a while (and I was making bagels in the meantime, to be honest, because brewing is a lot of waiting), but we made it. We then transferred the now cool wort – which needs to have as little contact with air as possible because like the good yeast, the bad stuff also really likes this temperature – to the fermentation container. I can tell you that it already smelled like a brewery in the kitchen – which totally makes sense because we were doing just that: brewing.
Step 5: Adding the yeast
We had already prepped the yeast by adding it to some lukewarm water, now it was ready to be added to the wort. Which we evidently did.
Step 6: Now we wait
We’re trying to keep the fermentation vessel at a constant temperature and keep any extra oxygen out. But other than that, there is nothing to do but wait. Updates will come soon, likely to tell you how it all went wrong. Maybe not.
Disclaimer: as with many things, I have no idea what I’m doing. This is not meant as an extensive guide to home brewing, but just as a general walk-through of my first attempt at brewing.
Cats are strange and the scientific community at least agrees on this fact. A 2014 study wondered what the physical nature of cats was, asking the very important question: are cats solid or fluid?*
Fluid dynamics for some very fluid cats.
Marc-Antoine Fardin used a scientific approach to answer the question “Can a Cat Be Both a Solid and a Liquid?”
Here was his conundrum: Cat’s are generally assumed to be solid. You know, you can touch them and they feel pretty solid. But on the other hand, cat’s fit into really small spaces and can seemingly adjust their form to the container they are in – a property usually attributed to fluids. This is commonly known in internet circles as “I fits, I sits.”
The author takes a rheological approach (rheology = the study of the flow of matter) to try to differentiate between whether the deformation of a cat is solid deformation or fluid flow. Solids can be deformed, especially if they are soft. Think Play-Doh, which can take any shape while keeping the same volume as opposed to honey, which can also take any shape while keeping the same volume but can be poured.
To me, “Can a cat be poured?” is the question worth asking, and this might be difficult to test without ending up with a lot of scratches.
Reading the paper, I was starting to think the author didn’t take his research very seriously (among his acknowledgments he thanks two people – or cats, I don’t know – for “providing a reliable technique to load Felis catus in different geometries: 1.Bring an empty box; 2. Wait.”). That said, studying the physical nature of cats could bring us closer to understanding the nature of matter itself. More recent experiments are promising:
It seems that the duality of cats extends beyond dead or alive.
Source: “On the Rheology of Cats,” Marc-Antoine Fardin, Rheology Bulletin, vol. 83, 2, July 2014, pp. 16-17 and 30.
* The study won the 2017 Ig Nobel prize for Physics. The prize awarded to science that first makes you laugh and then makes you think. To be honest, it makes you think that the whole thing was a joke in the first place. It probably was.
It’s happened to me. I’m sitting, calmly enjoying a sandwich outside on a bench, and then …
A seagull swoops in and tries to steal my food.
It’s terrifying. Seagulls are scary, especially up close and especially in Dundee, where I used to live and frequently sit outside eating something or the other. They have mean eyes.
I remember the seagulls in Dundee being quite peculiar. An anecdote: I was walking along the sidewalk, edging close to a corner where a seagull was digging through a ripped trash bag. When I was a few meters away, the seagull looked up and did this little walk away from the bag, pretending as if they weren’t just digging through trash. After I passed the corner, I glanced back and saw that they’d done a u-turn and went back to digging.
Okay, maybe I’m giving the bird too much of a personality. But it was weird.
Back to the food-stealing; a research conducted at the University of Exeter showed that if you stare at a gull, it is less likely to steal your chips (for US readers: french fries which are totally not from France but from Belgium and stop calling things the wrong name and, never mind, I’m okay).
Granted, the study had a limited scope. They tried to test 74 gulls, but more than half of them flew away. And it is likely that a lot of seagull related crime is due to a few bad seeds and most seagulls are perfectly happy leaving you and your food alone and digging through the trash for snacks.
Nevertheless, seagulls that were “looked at” while they were approaching food, were a lot less likely to touch that food. In fact, only a quarter of seagulls that were being watched while they tried to approach and eat food actually touched the food.
Maybe they were just scared of getting caught while committing food theft. Maybe they hate the color of our eyes. Maybe our stare is truly terrifying (I certainly know a few people with a scary stare). But next time you see a seagull approaching your food, give them the death stare. Perhaps your meal will be saved.
Perhaps drinking wine makes you all emotional. Perhaps drinking wine reminds you how you secretly enjoy beer better but then why do you have this weird stemmed glass in your hand? Perhaps you remember your early twenties when you lived in France and okay-to-good wine was very cheap and now you live in a country where okay-to-good wine is no longer cheap and cheap wine is sure to give you a headache the next day. Perhaps drinking whine makes tears run out of your eyes.
Did you ever stop to consider that crying over wine makes the wine cry as well?
Just kidding. I actually wanted to talk about wine tears. Which is the weird phenomenon where a ring of clear liquid forms in a wine of glass that has a bunch of droplets forming from it. Tears of wine. It’s a thing. A chemistry thing.
This type of “tears” appears because alcohol, you know that thing that is about 13% of that glass of wine your crying into, has a lower surface tension than water, which is that thing that most of the rest of that wine is made of. So like 85%, plus or minus a percent depending on how much crying you’ve done into the glass.
At the surface of the wine in your glass, where the liquid surface meets the side of the glass, capillary action causes the liquid to rise up the side of the glass. This thin film of liquid contains water and alcohol, both evaporate. Due to the higher vapor pressure of alcohol, it evaporates quicker than the water. This decreases the alcohol concentration in that liquid film, and consequentially also the surface tension, causing more liquid to rise up. Eventually, the liquid forms droplets that fall back into the wine. Gravity, it always gets ya!
So there. When you drink wine, just remember, you’re not the only one crying.
It is no secret that I’m a fan of giraffes. I have said this before, but I feel a certain sense of kinship with them. You know. Tall. Clumsy. Slightly derpy looking.
I was reminded of this when I found an old t-shirt on the bottom of my t-shirt shelf (yes, I have a t-shirt shelf. I’m incredibly organized. *ahem humblebrag ahem*). As you could have guessed, it has a giraffe on it. And that reminded me that I know a lot of random giraffe factoids.
So here are some tall stories, literally.
Giraffe Factoid Numero Uno:
Giraffes are about 2 meters (which is like 6ft6″ I think? Get with the metric, people!) tall at birth, making them world’s tallest baby and also the envy of all the guys on dating apps.
Giraffe Factoid II:
No two giraffes have exactly the same spot pattern. Basically, their spots are a bit like human fingerprints. This is very useful for giraffe-scientists – also known as girafologists (not really) – because it can help them recognize their study subjects easily without having to check for toe prints every time.
Giraffe Factoid Number Three:
Giraffes’ tongues can be up to 50 cm (20 inches?) long. *insert another tinder joke here*
This long tongue helps them eat. Giraffes binge on acacia leaves, which unfortunately grow on thorny trees. Thanks to the long tongue, they can reach around the thorns and get to the tasty leaves without getting a scratched tongue!
Their tongue is also blue-black-purple in color because it has a lot of melanin. This is probably to protect giraffe tongues from sunburn.
Giraffe Factoid Number 4:
Ironically, many giraffes have a fear of heights. I think this is why I identify so strongly with them… I too am tall and get dizzy even when just standing.
Giraffe Factoid Number now-for-real-number-four
Male giraffes test a female’s fertility by tasting her urine.
On the subject of urine, did you know that early pregnancy tests relied on… frogs? In the late 20s, a South African researcher discovered that if you injected certain hormones in a certain frog (Xenopuslaevis), they would start ovulating. These hormones are also present in the urine of a pregnant woman. With that, frogs became the first reliable pregnancy test!
Giraffe Factoid Number Fünf
If you have read Harry Potter, or any other British literature aimed at teens, you might think that necking means snogging. Which means kissing, the French way. But in the giraffe world, necking means smacking another giraffe with your neck. It looks scary.
Hey, did you know that giraffes have the exact same number of neck vertebrae as humans? They’re just a lot bigger. And presumably stronger, if they can do all that necking.
Giraffe Factoid Number Final-One
Giraffes are awesome. And if you don’t agree, well, that’s just your opinion! (The giraffes being awesome thing is totally objective.)