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Making Fake Meat Real: How Scientists are Tricking Your Tongue

Fake meat is often associated with a tough, flavorless texture that is added to dishes to provide protein. However, fake meat is no longer just glutinous balls or tofu hidden beneath sauces. From plant protein derived meats to in vitro preparations, there is much more to synthetic meat than what meets the tongue.

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Veggie Sausage. Photo Credit: (Heather Quintal/Flickr)

Replicating meat texture

Meat texture is very complex. Consider the multiple components from muscle tissue fibers, blood vessels, fat, gristle, to nerves. Each component confers a different texture and flavor profile, so replicating meat is quite a challenging process.

Texture plays a big role in determining whether a product tastes like real meat or not. For example, the satisfyingly stringy texture one gets from pulling apart chicken strips. Fortunately, food scientists have found ways to emulate the fibrous quality in fake meat using soy protein. Soy protein is initially globular, so it must be denatured, or broken down, to make it more fibrous. Soy protein is first exposed to heat, solvent, or acid, before it is reshaped with a food extruder [1]. Extrusion processes are useful as they can form meat analogs with fibrous matrices, which can then be rehydrated into meat like substances [2]. However, this process can sometimes result in a dry product. The rising company Beyond Meat has gone further and found a way to use soy flour, pea flour, carrot fiber, and gluten-free flour to emulate the fibrous quality in their fake meat with a wet extrusion process. The proteins are realigned and then locked in position by crosslinking to get a fibrous chicken imitation that is also moist and juicy [1].

Taste & color of meat

The flavors of meat mostly arise during the cooking process. Maillard reactions between sugar and amino acids produce those familiar meat flavors and aromas [3]. The amino acid glutamate is of utmost importance as it activates the umami taste receptors. Real meats contain glutamate as it is found in proteins, and it is released during proteolysis that occurs during meat aging and cooking [4]. Since most fake meats do not contain glutamate, this taste can be added back with soy sauce, tomatoes, mushroom, and cheese in the form of sauces [5]. Another unique aspect of meat is its color. The myoglobin proteins found in muscle are initially red due to heme pigments, but with the added heat of cooking, protein denaturation results in a brown color associated with cooked meat. For fake meat, food colorings and spices can be used to mask the original color.

In vitro meat: your steak from a petri dish

To minimize the number of animals slaughtered, some scientists are even growing animal tissue in the lab [3]. To do this, they take a small muscle tissue sample and look for skeletal muscle satellite cells, which are essentially individual stem cells that are normally used to create new tissue in case of damage. After these satellite cells are collected, they are bathed in a nutrient serum where they can be coaxed into growing. When large enough, they are shocked with an electric current, which causes the tissue to contract and thicken, resembling small fillets of meat a couple centimeters long and a few millimeters thick [3]. While meat products generated using this process are not available at your local supermarket (or butcher), and this product is not truly “meat-less” for vegetarians or vegans, it could potentially maximize meat production by saving cows from the slaughterhouse.

In vitro meat samples. Photo Credit (Janique Goff/Flickr).

In vitro meat samples. Photo Credit (Janique Goff/Flickr).

Fake meat efforts are attracting big investments from Bill Gates and Silicon Valley entrepreneurs, as the demand for meat increases. In fact, population growth and a boost in meat consumption have increased the global demand for meat threefold in the last 40 years [6]. Not only does this intensify the requirements for raising livestock, but it also increases the greenhouse gas emissions emitted during processing [6]. It is no wonder that the search for the best meat-replication process continues on! Whether from an animal or plant base, synthetic meat is becoming increasingly prevalent and is not just for vegetarians and vegans anymore.

References cited:

  1. How ‘fake meat’ is made. Mother Nature Network.
  2. Riaz, Mian N., Anjum, Faqir M., Khan, Muhammad Issa. “Latest Trends in Food Processing Using Extrusion Technology.” The Pakistan Society of Food Scientists 17.1 (2007): 53-138. Web.
  3. Fake meat: is science fiction on the verge of becoming fact? The Guardian.
  4. The Chemistry of Beef Flavor. BeefResearch.org.
  5. What Foods are Glutamate-Rich? Msgfacts.org.
  6. The Bill Gates-backed company that’s reinventing meat. Fortune.

Catherine HuAbout the author: Catherine Hu is pursuing her B.S. in Psychobiology at UCLA. When she is not writing about food science, she enjoys exploring the city and can often be found enduring long wait times to try new mouthwatering dishes.

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The Science of Bacon

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Photo Credit: Mai Nguyen

Imagine rolling out of bed on a Saturday morning, shuffling into your kitchen, and tossing a few strips of streaky bacon into a skillet. After a few minutes, you’ll hear a delightful crackling and sizzling, soon followed by a complex and savory aroma that could lure even the most resolute of vegetarians to the kitchen. As time passes, you peek into the skillet and notice the bacon begin to brown and bubble. After an agonizing wait, the bacon has finally reached a desired color and crispness and is ready to be consumed. You eagerly bite into a strip of bacon and are met with a pleasantly smoky taste, crunch, and a melt-in-your-mouth sensation. Bacon is a delight to eat, but it’s even better when you understand the science of why it’s so delicious.

There are two major factors that can explain why bacon has such a devoted fan base, with the first and more obvious factor being its aroma. Scientists have identified over 150 compounds responsible for bacon’s distinctive smell. As bacon cooks, there are a couple of different things going on. The Maillard reaction, the browning that results when amino acids in the bacon react with reducing sugars present in bacon fat, produces several desirable flavor compounds. This same browning reaction is also what forms the darkened and crunchy exterior on a pretzel or provides a stout beer with its characteristic color and taste.

During this process, bacon fat also melts and degrades into flavor compounds of its own. The compounds produced from the Maillard reaction and from the thermal degradation of bacon fat combine to form even more aroma compounds. In one study, scientists used gas chromatography and mass spectroscopy and revealed many of these aroma compounds to be pyridines, pyrazines, and furans, which were also found in the aroma of a fried pork loin that was tested. Pyridines, pyrazines, and furans are known to impart meaty flavors, so what actually sets bacon apart from the fried pork loin is the presence of nitrites. Nitrites are introduced into bacon during the curing process and are believed to react with aroma compounds in such a way that dramatically increases the presence of other nitrogen-forming compounds, including those meaty pyridine and pyrazine molecules. Ultimately, we can thank the high presence of nitrogen compounds as well as the interplay of fat, protein, sugars, and heat for bacon’s savory and unique aroma [1].

Now imagine that you’re eating breakfast. You alternate between bites of fluffy pancake drenched in maple syrup and mouthfuls crispy bacon, and maybe you’ll also have a side of velvety scrambled eggs. Here, you have a variety of textures on your plate –which brings us to our next concept to explain why bacon is so revered—mouthfeel.

Mouthfeel is described as the physical sensations felt in the mouth when eating certain foods. Bacon delivers a crunchy contrast to the softer textures found in scrambled eggs or pancakes in a mouthfeel phenomenon known as dynamic contrast. The brain craves novelty, and sensory contrasts will often increase the amount of pleasure that the brain derives from food, which is why you can find bacon as a textural accompaniment in many classic, creative, or sometimes questionable combinations. In a strip of bacon, you’ll see that it consists of lean meat that is heavily marbled with fat. During the cooking process, fat renders off leaving behind a product that simultaneously crisps and melts in your mouth when consumed, a texture combination that is rivaled by few other foods.

The melt-in-your-mouth phenomenon of bacon illustrates another nuance of mouthfeel, which is vanishing caloric density. Vanishing caloric density can be blamed for why it’s so easy to mindlessly consume massive amounts of popcorn, cotton candy, or other foods that seem to melt in your mouth. Upon ingestion of these foods, it is believed that the brain is tricked into thinking that you’re eating fewer calories than you actually are. Foods with vanishing caloric density have low satiating power but high oral impact, so your brain urges you to consume more, as it finds them more rewarding [2].

Between its tantalizing aroma and its delectable mouthfeel, it’s no surprise why bacon mania has so aggressively swept the nation.

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Now you can use science to justify eating an entire package of bacon in one sitting. Photo credit: Mai Nguyen

References cited

  1. Timón, M., Carrapiso, A., Jurado, A., van de Lagemaat, J. A study of the aroma of fried bacon and fried pork loin. Journal of the Science of Food and Agriculture, 2004; 84:825-831.
  2. Witherly S. Why Humans Like Junk Food. iUniverse, Inc.; 2007.

Mai NguyenAbout the author: Mai Nguyen is an aspiring food scientist who received her B.S. in biochemistry from the University of Virginia. She hopes to soon escape the bench in pursuit of a more creative and fulfilling career.

Read more by Mai Nguyen


The Science of Cookies

How would you describe your perfect chocolate chip cookie? Thin and chewy? Ultra-crispy? Thick and cakey? Whatever your preference, knowing how to manipulate the ingredients in a basic cookie recipe is the first step toward chocolate chip cookie bliss. At last week’s “Science of Cookies” student event, graduate student Kendra Nyberg showed us how to achieve two very different cookie textures by riffing off of the classic Toll House chocolate chip cookie recipe.

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Cookies wait to be tasted (left) while Kendra explains how gluten makes cookies chewy (right)

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Thin, chewy cookies (left) and thick, soft cookies (right)

Thin, Chewy Cookies from Smitten Kitchen
These cookies are all about moisture. A wetter cookie dough spreads more during baking, creating a much thinner cookie. Extra moisture also promotes gluten development in the cookie dough, creating a slightly denser, chewier cookie. This recipe from Smitten Kitchen maximizes moisture content by using melted butter, less flour, less egg white (which can dry out cookies), and a higher brown-to-white sugar ratio (brown sugar can help retain moisture) than the classic Toll House Recipe.

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Thick, Soft Cookies from My Baking Addiction
Where the previous cookies craved moisture, this recipe from My Baking Addiction removes extra moisture to create thicker, less chewy cookies. Increasing the flour content and using extra cold butter creates a drier dough that spreads less easily in the oven; adding baking powder to the dough lends extra fluffing power. The reduced moisture in this dough also limits gluten formation for a slightly softer (less chewy) cookie.

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Of course, this is barely the tip of the cookie engineering iceberg. There are so many ways to tweak a cookie recipe to achieve different textures. In addition to this brief introduction, the internet is full of great resources for cookie hacking. This particularly handy guide from Handle the Heat clearly show some of the ingredient manipulations described above. If you end up experimenting with your favorite cookie recipes, be sure to tell us about it in the comments below!


Liz Roth-JohnsonAbout the author: Liz Roth-Johnson is a Ph.D. candidate in Molecular Biology at UCLA. If she’s not in the lab, you can usually find her experimenting in the kitchen.

Read more by Liz Roth-Johnson


Squishy Physics & The Molecules We Eat

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This week we’re all about texture! The Fernbank Science Center dives into the squishy physics of soft (food) materials, while Amy Rowat explains how food can help us understand the different textural properties of cancerous cells versus healthy cells. Read more