What Color is Your Cheese?

You've heard the saying that a diner eats first with her eyes, meaning that the way things look can influence our perception and enjoyment of food. Over at The Kitchn, the resident Cheesemonger Nora Singley wrote a post about the origins of the different colors of cheese and what they can indicate about the type of cheese you're looking at.

Here's the shorthand:
Orange: artificially colored cheese, including cheddar and processed cheese
Yellow: Grass-fed cows' milk
White: Goat
Blue: Contains mold

What I found most interesting was that, while cows' milk contains beta carotene, goats' milk does not. That means that if a cow consumes more beta carotine in its diet, its milk will contain more beta carotine and cheese made from this milk will be more yellow. On the other hand, no matter how much grass a goat eats, its milk and cheese will be perfectly white. Some food historians believe that the reason people began dyeing cheese orange was to mimic the yellow color of cows' milk cheeses from the spring and summer, times of the year that the cows' normally would be eating more grass and also times of the year when the milk was full of fat and flavor.

(Image: Blue Cheese, a Creative Commons Attribution 2.0 image from Liz Davenport's photo stream)

Homemade Astronaut Ice Cream

One small step for man...

As a kid, after visiting almost any natural history or science museum, a package of freeze-dried "astronaut" ice cream was one of my favorite treats. I still like it today, actually, even though I think it's mostly the nostalgia and not the taste. Via BoingBoing, I found these instructions for making your own, homemade freeze-dried ice cream, assuming you have access to a vacuum pump and some laboratory glassware. Although it seems like a bit of work, the limitless flavor possibilities are intriguing. Also, I suppose you could use this setup to freeze-dry all sorts of foods, not just ice cream. Tasty.

(Image: astronaut ice cream, a Creative Commons Attribution 2.0 image from Rakka's photostream)

Pizza is still a vegetable.

Today the United States Department of Agriculture (USDA) introduced new guidelines for school lunches, intended to make the lunches healthier. These new guidelines, including limiting the caloric range for school lunches and requiring that each lunch have at least two servings of vegetables, seem like a step in the right direction. Despite all of the general pats on the back I see going around the internet, however, the guidelines are still far from perfect. Thanks to agri-business lobbies in congress, the tomato paste in pizza is still counted as a vegetable, and the proposal to limit servings of french fries (another "vegetable") did not make the cut. Baby steps, congress, baby steps...

Science of Beating Eggs

My friend Lynn tipped me off to a neat story on the NPR website about the science of beating eggs. Read it if you'd like to get some pro-tips (from a real chef!) on beating egg whites into a foam for use in a souffle (or other whipped-egg-white application, such as meringue).

The first trick is to separate your eggs (that is, separate the yolks from the whites) without letting any of the egg yolks contaminate your whites. This is important because, while the egg white is entirely made of protein, the yolk contains some fat. When you whip the egg whites, you denature some of the proteins, which unfold and expose some hydrophobic areas. These hydrophobic areas would rather stick to each other than to the surrounding water, so the proteins stick together, creating a sort of net that can surround air bubbles, creating a foam. This foam is what makes whipped egg whites fluffy. If you contaminate your whites with the fat from the egg yolks, the hydrophobic areas of the egg white proteins will interact with the fat from the yolks instead of each other, leaving you with no net of denatured protein in which to catch bubbles. No bubbles means no foam.

Another note: if you over-beat the egg whites, continuing to beat them after a proper foam has formed, the egg white proteins will coagulate completely, sticking together so strongly that they force out all of the liquid between them, leaving you with a clumpy, separated, egg white mess.

If you're more of a visual learner and are interested in learning this useful kitchen technique, check out this how-to slideshow from Serious Eats or this excellent segment on souffle from the ever-informative Alton Brown from Good Eats.

Related: The Science Behind Poaching an Egg

(Image: Soufflé, a Creative Commons Attribution 2.0 image from David_Turner's photostream)

Growing Vegetables In the Cloud

Artists rendering of the new Nikkei vegetable growing system from Panasonic.

(Image via TechCrunch)

It seems that lately food trends have been moving in the low-tech direction. Slow food, local, organic, grass-fed, heritage, biodynamic - all sorts of words describing us basically getting back to our roots with regards to growing produce and farming animals. Mostly I'm inclined to think this is a good thing. There is all sorts of evidence to show that many aspects of the modern industrial-agricultural complex are harming our environment and hurting our bodies. However, we can't go back to the way we farmed food 100 years ago without creating a shortage of food for our current ever-increasing population. What's the fix?

One way could be to blend modern technology with old farming practices. For example, growing organic heritage greens in a high-tech rooftop garden. I discovered one company, Gotham Greens, doing something similar. This company is growing local vegetables and herbs for restaurants and consumers in Brooklyn, New York City, in a high-tech hydroponic rooftop garden set up in an abandoned bowling alley. Also recently, Panasonic introduced a new product for people who desire to grow vegetables, indoors or our, at home with a super high-tech system that allows users to monitor vegetable growth and manage the garden using a cloud-based computing system. Right now the system is prohibitively expensive for most people at around $8000, but if there is enough demand for this type of technology, every home could soon have its own high-tech victory garden, helping the effort in the war on carbon-footprints and fossil fuel dependence.

The Ongoing Quest for In Vitro Meat

For many years, people who think about these things have posited that lab grown meat could replace meat from animals as food, thus eliminating all of the animal cruelty and environmental issues associated with farming animals for meat. "Cultured meat" could be the choice of future carnivores.

However, making this meat is easier said than done. Growing muscle tissues in a laboratory setting is not an easy task, nor, it turns out, is it cheap. Right now, it requires many man hours and expensive supplies and equipment to grow mammalian cells in culture. Muscle cells, the kind that make up the animal meat we eat, also needs to be stretched or exercised in order to develop into tasty muscle. As an additional hurdle, many in vitro mammalian cell culture systems used by scientists use products made from farmed animals. If laboratory meat is going to be made in a way that does not harm animals, components like this are off the table.

Additionally, if people are to eat this in vitro meat, it would have to taste something like meat from animals, and would have to be comparably priced. That requires some advancements in the methods and technology currently used to grow tissue in culture. In an effort to promote innovation on this front, currently PETA (People for the Ethical Treatment of Animals) is offering one million dollars to anyone who can produce and affordable lab-grown replacement for chicken before June 30, 2012.

Recently, however, there has been some progress toward the production of cultured meat. Dutch scientists have created lab-grown meat from bovine stem cells harvested from a slaughterhouse. The "meat" consists individually grown sheets of muscle tissue, grown in culture using Velcro tabs to stretch the fibers so that they develop properly. Right now, the cost of a hypothetical burger made out of this meat, consisting of hundreds of thousands of sheets of muscle tissue, is estimated at $345,000. That's still a little steep for consumers, but the scientists say they plan to produce one as proof of principle within a year. Since the tissue is grown without a circulatory system, it lacks blood and is white in color, and it also lacks the associated fat of meat from an animal. Currently, the scientists say that improving the taste and color, possibly by adding laboratory-grown fat or blood, are goals that they are working towards.

Proponents say that this meat could replace or supplement modern factory farming as a more sustainable, cruelty-free meat product. However, challenges include making the meat palatable, ensuring that the product appears appetizing, and producing it at a cost where it can compete with farmed meat.

Until your laboratory-grown burger becomes available commercially, if you'd like an environmentally friendly, affordable, laboratory-grown protein, you'll have to be satisfied with mycoprotein (which, as an omnivore, I find quite tasty, even though it's not meat).

(via BoingBoing)

(Image: ...meat x 250, a Creative Commons Attribution 2.0 image from x ray delta one's photostream)

Probiotics - How Do They Work?

(Image: Yogurt Parfait, a Creative Commons Attribution (2.0) image from mrdestructicity's photostream) 

In the past couple years, there has been a lot of debate (and at least one lawsuit) regarding the effectiveness of yogurt and other foods and supplements that contain "probiotics," or beneficial microorganisms. Various studies have linked the consumption of probiotics to various health benefits, including treatment of gastoenteritis and diarrhea, lowering cholesterol, improving immune function, and reducing inflammation, among other claims. However, most of these studies studied one particular strain of bacteria, so results may not be applicable to all probiotics, and many studies involving humans show correlation with positive health outcomes, but not causation. To date, little is known with scientific certainty about the effectiveness of probiotics, and even less about how they function in the human body.

A recent study has evidence that probiotics may function by altering the expression of genes in your gut bacteria, thereby altering their metabolism of the foods that are present in your gut. After feeding mouse and human subjects probiotics, researchers at Washington University in St. Louis found that, although the composition of gut bacteria were not altered, gene expression of the gut bacteria of the mice were. The effects of the resulting metabolic changes could be observed in the mice's urine.

This study sheds some light on a previously mysterious process. It seems that probiotics may have a real effect on the human digestive system. Hopefully further studies will be able to further elucidate the mechanism of the changes brought about by these organisms and help us to understand which strains may be beneficial and for what purpose.

(via BoingBoing)