Happy new year from Bite-Sized Biology! I hope you all had a wonderful holiday season. One of my favorite ways to celebrate the holidays is to bake lots of holiday cookies, and this year I made a big batch of molasses spice cookies for my lab’s holiday cookie exchange. They were so tasty that they disappeared before I could even take a picture! In return, I received every kind of cookie from cherry chocolate-chunk to chocolate-hazelnut pinwheels.
Of course, baking lots of holiday cookies also means eating lots of holiday cookies. And that means eating lots of sugar. But did you know that sugar is more than just a tasty treat the bane of a holiday dieter’s existence? Sugar plays several important roles in our cells and is even a part of our DNA! What we call “sugar” is really just a few molecules — namely sucrose, glucose, and fructose — that belong to a much broader class of sugar molecules called carbohydrates. The sugar “ribose” is an important building block of our DNA. Ribose is a five-carbon sugar that resembles fructose, the sugar found in fruit.
Sugars can also act as informational molecules in the cell. Different combinations of sugars like mannose, galactose, and fucose can decorate the surfaces of proteins and lipids to create a special cellular code: the sugar code. This sugar code is particularly important for helping cells recognize and interact with one another. Sugars displayed on the outer surfaces of cells can mediate cellular interactions and provide important identification signals. For example, our T cells (a type of white blood cell) take advantage of the sugar code to target sites of inflammation. Several viruses and bacterial toxins use the sugar code to infect cells by binding to specific groups of sugars on the cell surface. Sugar-based pharmaceuticals like heparin (an anticoagulant) and acarbose (an anti-diabetic drug) are even commonly used to treat a variety of ailments. So think about that the next time you whip up a batch of delicous, sugary cookies!
dlnpnndhk asked: your blog is REALLY amazing. you're kind of motivate me :) I study food technology (still grad student). maybe someday we can work together!
Thank you! That’s high praise coming from someone who is actually studying food technology! I’d love to hear your ideas for future posts… Or maybe even a guest post if you feel like sharing a little bit about yourself and what you study as a food technology grad student? Could be fun!
praan asked: I'm an undergrad student of genetics and I want to go to grad school... and my interest in cooking is growing. Your blog is so cool, I'm so glad I found it!
I’m glad you found it, too! I have to say, cooking and grad school are both pretty awesome, though I might be a bit biased. I don’t know what your specific interests in genetics are, but with research on everything from transgenic crops to the genetics of human metabolism, it’s definitely a great field to be in if you’re interested in food and nutrition. Good luck in your studies and happy cooking!
Hi there! I hope you all had an amazing summer and are enjoying this fabulous fall season. While I was away, I spent two months playing mad scientist in Woods Hole, Massachusetts. This involved lots of science, seafood and… popovers! For some reason I just can’t understand, California has yet to embrace the utter awesomeness that is popovers. So when this California girl met these bad boys at a little place called Pie in the Sky, it was love at first sight.
I ate popovers like there was no tomorrow. Popovers with my coffee. Popover sandwiches for lunch. Even popovers at 4 a.m., fresh from the oven. I was addicted, and when I returned home, there was a giant, popover-shaped hole in my life. There was only one thing to do — start baking my own popovers! Unfortunately, baking popovers is notoriously tricky. After several attempts, my popovers are still inconsistent and don’t have quite the “pop” I’m looking for.
The first few batches I cooked at my parents’ house (left) weren’t too shabby. But when I tried again in my own oven (right), the popovers were doughy and mishapen. So began my quest for the perfect popover.
Popovers are like little balloons. An elastic network of egg, milk, and flour proteins (particularly gluten) forms as the popover batter is mixed. This rubbery network then “inflates” as air trapped inside the batter expands during baking. As with most baked goods, the success of this process comes down to two primary factors: mixing and heat.
Mixing is important for more than simply blending ingredients together — it promotes the formation of elastic protein/gluten networks and incorporates air into the batter. There is something of a sweet spot when it comes to mixing popover batter. While Harold McGee advises vigorous beating, Betty Crocker warns not to overmix. Talk about mixed messages! Lucky for us, someone has already tested several different mixing methods side-by-side. While a standing mixer will give passable results, a little elbow grease and a good old fashioned wire whisk works like a charm. And don’t even think about putting that batter in a blender unless you prefer dense, doughy blobs of popover death.
Even if you’ve managed to perfectly mix your batter, you might as well say goodbye to perfect popovers if you don’t have a piping hot oven. Heat produces the steam that inflates the popovers as they bake, so less heat can mean underinflated popovers. But there’s another reason heat is key. Remember my sad, concave popovers? My oven wasn’t hot enough to seal the steam inside the popovers. To avoid this problem, it’s important to set the surfaces of the popover batter as quickly as possible. This is why recipes will often call for preheated or even cast iron popover pans.
With all of this new information in hand, I’ll continue on my quest for the perfect popover. Fingers crossed for the next batch!
Bite-Sized Biology will be taking a short break over the summer. I know, I know… I’m bummed about it, too. But between being away for an intense seven-week cell biology class and studying for my PhD qualifying exam, I really won’t have any extra time for blogging. But don’t worry! There’s still lots of food and science fun to be had, and I’ll be back in action before you know it.
In the meantime, I thought I’d leave you with a few things to explore while I’m away. My last post got me thinking more about the way agriculture presents an interesting intersection of science, society, the economy, and the environment. This first piece explores what can happen when scienctific research conflicts with the economic interests of industry.
Hosted by UC Berkeley’s Graduate School of Journalism in 2003 (and with an eloquent introduction by Michael Pollan of The Omnivore’s Dilemma fame), this panel features four prominent scientists who have come under fire for making important scientific discoveries that question the practices of the agricultural biotech industry. One thing that really stands out to me in this conversation is the open-mindedness of the four scientists. None of these scientists purposely went after the biotech industry when they first started their research. Arpad Pusztai, for example, was genuinely surprised when he first discovered that genetically modified potatoes have adverse effects on rats. Unfortunately, industry has made it all but impossible to have a fair and open conversation about this kind of research. Says John Losey,
“If we can start to have negative [research] results as well as positive [research] results respected, then we can start to have some really constructive dialogue, and then we can really see if maybe some of these genetically modified organisms, transgenic plants, are going to actually be an environmentally sound option. But we can’t really get to that point, we can’t start making progress, until we can get past the battle lines.”
The second thing I’d like to share is a set of video lectures from iBioSeminars* about genetically modified crops.
Pamela Ronald, a professor at UC Davis, has an especially unique perspective on transgenic crops. Why? Because she’s married to an organic farmer! She and her husband, Raoul Adamchak, have even written a book together called Tomorrow’s Table (you may have heard about it from this guy). You can also check out Ronald’s blog if you’d like to read more about her thoughts on food, farming, and genetics.
In her video, Ronald brings up an important point about GMOs:
“It’s not the method of introducing genes that’s critical, but it’s the product. What is the variety that’s being developed, and who do those varieties benefit?… All new crops must be considered on a case by case basis. We cannot simply say that genetic engineering is all beneficial or all harmful; we really need to look at the crops developed through this technique.”
I’ve expressed a similar sentiment in my past posts about GMOs. “Genetically modified organism” is suchabroadterm that it really makes no sense to discount (or accept, for that matter) the potential benefit of a GMO simply because its DNA has been altered in some way. The real questions we need to ask should address the environmental, social, and economic impacts of each unique GMO. In her own work, which she explains in part two of her lecture, Ronald creates and studies disease- and flood-resistant transgenic rice to benefit farmers in third world countries. I think it will be interesting to watch the evolution of GMOs as more scientists turn to genetics to address the challenges of global food production and sustainability.
The issue of sustainability in agriculture is a common theme in Ronald’s lectures and a major issue now facing our food production system. In keeping with this theme, I’ll end with something a little more fun, but equally important:
And with that, I’m off. I wish you all wonderful summers full of science, discovery, and culinary conquest. See you in the fall!
*While you’re over at iBioSeminars, you should check out the rest of the website, too! This is a really unique and fantastic resource for anyone interested in biology and biological research.
About week or so ago, I went to a particularly fantastic research seminar given by Dr. Tyrone Hayes from UC Berkeley. In addition to being an excellent scientist, Dr. Hayes has gained a lot of attention for being a particularly outspoken advocate for the banning of atrazine.
First registered with the EPA in 1958, atrazine is now one of the most widely used agricultural herbicides in the world. Dr. Hayes began studying atrazine over a decade ago when he was hired by a consulting company to research atrazine on behalf of Syngenta, atrazine’s manufacturer. However, his work with Syngenta was short-lived; Dr. Hayes left his consulting job soon after his own reserach began to cast atrazine in a negative light.
Over the years, Dr. Hayes has continued to study atrazine, despite continuous attacks and counter-studies from Syngenta. It’s a fascinating story from both a scientific and a social perspective, and it’s really best told by Dr. Hayes himself. You can also read more about atrazine at Dr. Hayes’ website.
So why does all of this even matter?
As Dr. Hayes explains in his talk, atrazine affects male frog development by disrupting the delicate balance between the two sex hormones, estrogen and testosterone. Importantly, these two sex hormones are identical in all animals, and several scientists have independently discovered that atrazine acts as an endocrine disruptor in fish, amphibians, reptiles, and rodents. And if atrazine disrupts hormone balance in fish, amphibians, reptiles, and rodents, it’s more than likely that atrazine also disrupts horomone balance in humans. Of course, Syngenta denies any such claims (not that it should come as any surprise).
But even if we completely ignore this threat to our own health, atrazine still poses a clear threat to the environment. In 2003, the National Resources Defense Council sued the EPA for failing to protect several endangered species from atrazine. The Center for Biological Diversity similarly sued the EPA in 2002; as a result, the threatened California red-legged frog is now protected from atrazine and 65 other pesticides. To quote Dr. Hayes:
“Given atrazine’s solubility in water, aquatic animals such as fish and amphibians are at the greatest risk… Several salmon and trout species are already endangered or threatened as are other fish. Amphibians are also very sensitive to endocrine disruptors and given that already more than 60% of all amphibians are in decline and a third are threatened or endangered, atrazine is of great concern…” What You Should Know About Atrazine: Endangered Species
Such ecological ramifications and likely health risks should make us seriously question our use of atrazine and other pesticides. So what can we do? We can join the discussion! If petitions are your thing, you can check this one out. I’m sure the EPA, congress, and Syngenta would also love to hear your thoughts. The EPA has already stated that the ultimate decision regarding the regulation of atrazine “weighs into public opinion”, so let’s give them an opinion.
redblackapron asked: Your blog is amazing! I love to bake and always research on why certain reactions happen when you mix different ingredients together or when you cook things different ways. Most people may think that baking (or cooking) is just an art but it really is a science too! :)
How exciting to be featured alongside so many fabulous food blogs in Tumblr’s new Food Spotlight. A big thank you to Tumblr and an even bigger welcome to all of you who are new to Bite-Sized Biology!
Be sure to also check out the awesome blogging over in the Science Spotlight. There’s lots of great stuff you won’t want to miss!
stevenhle asked: What are you going to grad school for?
I'm currently pre-med, sorta and kind of want to switch to culinary arts.. I don't know what I should do. Haha. Right now, I'm thinking of switching to business and then going to culinary school later.
And also, I love your blog!
Why thank you - I’m glad you like it!
I study biochemistry and cell biology. My research focuses on the cytoskeleton, a dynamic network of protein filaments known as actin, microtubules, and intermediate filaments. The cytoskeleton helps organize the contents of cells, gives cells shape and structure, and allows some cells to move.
That might sounds strange, seeing as I blog about food and cooking. But I guess it just goes to show that whatever career path you decide to take, you can always pursue your other interests on the side. What I do at school has nothing to do with food or cooking, but I make time for it because I enjoy it. There’s nothing stopping you from pursuing a career in business or medicine while being an awesome cook on the side. Doctor by day, chef by night - I think it could work!
