Ah, spring. The perfect time of the year to take a stroll, smell the roses, and then stop by the local bakery to taste the roses. Whether in Persian or Middle Eastern desserts such as rose-flavored raahat or baklava, or French-inspired rose scones and marshmallows, roses have an elegant flavor that is a delicate mix of sweet and floral. In celebration of spring, here are 7 things about the flavor of roses to mull over while enjoying a cup of rose hip tea: Read more
Tag Archive for: flavor
Ever put a slab of pork shoulder or beef brisket on the smoker for a BBQ, only to eventually hit “The Plateau”? Physicist Dr. Greg Blonder has the explanation for why the temperature of these meats will rise steadily for a few hours before it inexplicably stops and stalls at several degrees lower than the ideal 190°F. Fortunately, his explanation also comes with a solution. Once that dilemma is solved, check out the science that makes meat so delicious.
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 .
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 .
Between its tantalizing aroma and its delectable mouthfeel, it’s no surprise why bacon mania has so aggressively swept the nation.
- 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.
- Witherly S. Why Humans Like Junk Food. iUniverse, Inc.; 2007.
About 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.
Want beer foam that doesn’t dissipate right away? Microbiologist Tom Villa made a genetic discovery in yeast that could create beers with longer-lasting beer foam. This yeast, however, doesn’t quite affect the taste, so find out where beer flavor comes from.
How does sipping a cup of lavender tea with honey sound? Soothing? Fragrant? Then imagine stumbling upon an open field of lavender flowers. The lavender plant, genus Lavandula, comprises 39 flowering plant species, all of which are easily recognized by that trademark color and signature fragrance. The most popular species of lavender is L. angustifolia, commonly known as English lavender and lauded for having the sweetest fragrance among lavender plants. Lavender flowers are primarily grown in order to extract the essential oil for both medical and culinary uses.
The distinctive purple flower is popular for its calming abilities, extensively used in aromatherapy alongside other herbs. Lavender is additionally famed for its healing properties. French chemist, René-Maurice Gattefossé realized the usefulness of lavender oil as a healing essence when he plunged his burned arm into a tub of liquid containing lavender oil, later noting quick tissue regeneration with little scarring [1,2]. Following Gattefossé’s observation and subsequent experiments using lavender oil in military hospitals during World War I, lavender is also used today as an antiseptic and anti-inflammatory . As an herb, lavender of course has a dedicated fan base in the culinary world; the fragrant flower is the star of recipes such as lavender cake, lavender shortbread, and even lavender and honey roasted chicken.
Analysis of lavender oil reveals the primary compounds responsible for the scent are linalyl acetate and linalool (pronounced lin-ah-low-awl). Both have been cited to contain various pharmacological properties that aid in relaxation, such as anti-anxiety, anti-depressant,  and relaxant of vascular smooth muscles .
Minor volatile components that contribute to the scent of lavender essential oil include (E)-β-ocimene, (Z)-β-ocimene, terpinen-4-ol, 1,8-cineole, camphor, and limonene.
But make no mistake. There’s nothing “minor” about these compounds when it comes to lavender flavor. According to the flavor network by physicist Albert-László Barabási, North American and Western European cuisines like to pair ingredients that share many flavor compounds. Camphor confers a woody, evergreen scent and is one of the primary volatile compounds in dried rosemary leaves; this makes lavender and rosemary a comforting combination. Further, linalyl acetate, linalool, and many of the minor volatile components of lavender oil can also be found in lemon peels and lemon essential oil . Lavender and lemon are such celebrated culinary companions that the two are practically best friends.
Want to try cooking with lavender for the first time? Relax; it’s not as challenging as it seems. Just take a deep breath and try out this simple lavender sugar recipe.
- Tankeu SY, Vermaak I, Kamatou GPP, Viljoen AM. Vibrational spectroscopy and chemometric modeling: An economical and robust quality control method for lavender oil. Industrial Crops and Products, 2014; 59: 234-240.
- René-Maurice Gattefossé. Oils and Plants. Accessed 2014, December 21.
- Koto R, Imamura M, Watanabe C, Obayashi S, Shiraishi M, Sasaki Y, Azuma H. Linalyl acetate as a major ingredient of lavender essential oil relaxes the rabbit vascular smooth muscle through dephosphorylation of myosin light chain. Journal of Cardiovascular Pharmacology, 2006; 48(1): 850-856.
- Oboh G, Olasehinde TA, Ademosun AO. Essential oil from lemon peels inhibit key enzymes linked to neurodegenerative conditions and pro-oxidant induced lipid peroxidation. Journal of Oleo Science, 2014; 63(4): 373-381.
Flavor may have had an driving role in human evolution. In that same cup, just the flavor of beer may be required to make you feel happy, no alcohol required.
Caramel flavor is a major component of desserts and candies, ranging from smooth, thick sauces to crispy, dark brown glazes of crème brûlées. Through caramelization, a browning process where sugar is heated to around 170 °C and broken down, over 100 compounds are formed that contribute to the color, flavors, and textures of what we know as caramel .
One simple way to caramelize table sugar is by heating: this process removes water from the disaccharide sucrose (a substance composed of two simple sugars) and breaks it down into monosaccharides fructose and glucose. Next, the monosaccharides react with each other to form new compounds, such as caramelan, caramelen, and caramelin . These compounds aggregate to form brown particles of various sizes due to additional water elimination, contributing to the characteristic brown color of caramel. The stickiness of caramel can be attributed to the ring form of these molecules combined with the presence of free radicals . Further, when in the presence of alkali, sulphite, or ammonia, these compounds can also result in colorants used in food products such as soy sauce and Coca-Cola .
In addition to these classic caramel compounds, many other molecules are produced that result in different aromas that contribute to caramel’s complex flavor profile, such as furans (nutty), diacetyl (buttery), maltol (toasty), and ethyl acetate (fruity) .
How to tune the flavor of your caramel? The temperature the sugar is heated to determines caramel flavor. “Light caramel” (180°C) can be used for glazes, is rich in flavor, and pale amber to golden-brown in color. By contrast, “dark caramel” (188-204°C) is dark and bitter in flavor due to increased oxidation of the sucrose molecules; it is usually used for coloring. Additional heating past this point will turn the caramel into a black and bitter mess, as the sugar breaks down into pure carbon .
Interestingly, caramel candies made with milk or butter do not undergo the caramelization process. Instead, the heating of the dairy product in the recipe causes Maillard reactions between sugar and amines that result in the brown color and flavors produced .
Next time you enjoy caramel flavor, you can revel in the smell and taste of all the aromas that result from complex chemical processes. Or, simply make your own with sugar, water, and a stove.
- “Caramelization.” Accessed 21 October 2014.
- “Caramelization.” Accessed 21 October 2014.
- “The Chemistry of Caramel.” ScienceGeist. Accessed 21 October 2014.
- “E150 Caramel.” Accessed 21 October 2014.
About 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.
At our 2014 public lecture How We Taste, Chef Wylie Dufresne, Dr. Dana Small, and Peter Meehan explored the tantalizingly complex concept of flavor. The evening was full of scientific discovery, childhood memories, and culinary innovation. In honor of this enlightening event, here are 5 things you might not know about our sense of taste:
Among fruits, bananas enjoy huge popularity. The Market and Policy Analyses of Raw Materials, Horticulture and Tropical (RAMHOT) Products Team even reported that within the U.S. in 2012, per capita banana consumption was calculated at 13.8kg . The humble banana even reigns as the main fruit in international trade, according to the Food and Agriculture Organization of the United Nations (FAO) . But as a flavor? Banana candies are often the last flavor left in the bowl.
The disparity between the pleasant and sickening feelings which banana flavoring can invoke lies in the intricacy of banana flavor chemistry. The fruit itself contains a mixture of volatile compounds that are responsible for its characteristic flavor. Up to 42 molecules have been identified to contribute to the aromatic profile of bananas . Each of these molecules, when isolated, has been reported to give off their own unique scent [2,3]. Most of the scents are described as floral, sweet, and generally fruity, which are expected when analyzing aroma compounds derived from bananas. However, there are a few volatile compounds that emit odors not usually associated with bananas. For instance, eugenol, one of the significantly abundant aromatic compounds found in bananas, smells spicy, like cinnamon [2,3].
Of all the volatile compounds detected in bananas and analyzed, one stands out as the banana flavor molecule: isoamyl acetate. With a scent often described as “over-ripe bananas”, pure solutions of isoamyl acetate are sold as “banana oil”. Isoamyl acetate is widely used as a flavorant to confer that over-ripe banana flavor in foods. Yet, as many can attest, pure “banana flavor” tastes awful, nothing like the actual fruit. Despite its presence in the banana itself, how does the banana-flavor molecule miss the mark so badly in candy?
Chemical complexity is one explanation, as there are 30-40 other aroma compounds that contribute to natural banana flavor. Additionally, in a ripe banana, although isoamyl acetate is one of the key molecules in banana aromatics, it is found in small amounts compared to the other volatile compounds [2,3]. Yet, even though isoamyl acetate is not the most abundant compound in the aromatic profile of bananas, it is a heady flavor on its own: this molecule can be tasted in concentrations as low as 2 parts per million .
So, maybe a banana-flavored Laffy Taffy contains a higher concentration of isoamyl acetate than an actual banana. Until scientists and flavor chemists figure out how to make banana-flavored foods actually taste like bananas, at least the yellow Laffy Taffy has its small but dedicated fan base.
- Banana Market Review and Banana Statistics 2012-2013. (2014). Retrieved October 2, 2014.
- Jordán MJ, Tandon K, Shaw PE, Goodner KL. Aromatic profile of aqueous banana essence and banana fruit by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). J Agric Food Chem. Oct 2001;49(10):4813-7.
- Pino J, Febles Y. Odour-active compounds in banana fruit cv. Giant Cavendish. Food Chemistry. Mar 2013;141(2013):795-801.
- Bilbrey, J. (2014, July 30). Isoamyl acetate. Retrieved September 28, 2014.
One rhizome, many tastes. Ginger can be charmingly sweet as candied ginger, gingerbread, and ginger ale. Just as easily, this root can be spiritedly pungent, as in gari (sushi ginger) or unsweetened ginger tea. From sugary snacks to savory dishes, ginger shares similar flavor versatility as cardamom, which should come as no surprise; the two spices are practically cousins. All ginger plants are of the genus Zingiber, which belongs to the same family as cardamom plants, Zingiberaceae . However, the supermarket ginger that most people are familiar with is the knobby, root-like rhizome of Z. officinale, better known as the garden ginger.
Fresh ginger gets its pungency and aroma from the flavor compound, gingerol. Studies have extolled gingerol for its many pharmacological abilities, including antipyretic (fever reducer), analgesic (pain reliever), anti-inflammatory, and antibacterial . The best part? Chemically altering gingerol ends up tweaking ginger’s flavor profile, which helps give ginger its flavor versatility. No laboratories or fancy equipment are needed; as long as there’s a kitchen and a love for ginger-flavored foods, fine-tuning the flavor of ginger is rather straightforward.
Heating a ginger rhizome causes gingerol to undergo a reverse aldol reaction, transforming it to zingerone, a molecule that is completely absent in fresh ginger. Like gingerol, zingerone is responsible for the pungency of cooked ginger, but it also lends a sweeter note to the flavor. For this reason, cooked ginger makes a delightful treat as candied ginger. Zingerone also boasts quite a few pharmacological benefits, notably, its many anti-obesity actions . For instance, zingerone was shown to inhibit obesity-induced inflammation, as well as stimulate the release of catecholamine, a hormone that aids in decreasing fat cells .
Drying a piece of ginger triggers a dehydration reaction, changing gingerol to shogaol. Shogaol is twice as spicy as gingerol, which is why dried ginger packs more heat than its fresh counterpart. Additionally, shogaol retains gingerol’s bioactivity, reported to act as an antioxidant, anti-neuroinflammatory, and even memory-enhancing agent .
With a multitude of benefits and just as many ways to serve it, there’s really no wrong way to enjoy ginger.
- Zingiber. The Plant List (2010). Version 1. Published on the Internet; (accessed 13 August, 2014).
- Young H.-Y, et al. Analgesic and anti-inflammatory activities of -gingerol. Journal of Ethnopharmacology. Jan 2005; 96(2):207-210.
- Pulbutr P. et al. Lipolytic Effects of zingerone in adipocytes isolated from normal diet-fed rats and high fat diet-fed rats. International Journal of Pharmacology. Jul 2011; 7(5):29-34.
- Moon M, et al. 6-Shogaol, an active constituent of ginger, attenuates neuroinflammation and cognitive deficits in animal models of dementia. Biochemical and Biophysical Research Communications. June 2014; 449(1):8-13.