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Cranberry

Cranberries are harvested in late autumn, just in time to celebrate the holidays. Whether you prefer to enjoy cranberries in a jam, as a sauce from the can, juiced, dried, or fresh, there’s no denying that cranberries are festive. They’re tart, dark red, and pair really well with a turkey dinner (according to science). Read more

Lavender

Lavender Cream

Lemon curd pudding lavender cream
Photo credit: Sue O’ Bryan (Foodlander/Flickr)

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 [1]. 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, [1] and relaxant of vascular smooth muscles [3].

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.

Minor compounds

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 [4]. 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.

References cited

    1. 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.
    2. René-Maurice Gattefossé. Oils and Plants. Accessed 2014, December 21.
    3. 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.
    4. 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.

Alice PhungAbout the author: Alice Phung once had her sights set on an English degree, but eventually switched over to chemistry and hasn’t looked back since.

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The Flavor Network

Physicist Albert-László Barabási likes making connections. By studying networks, Barabási and his Northeastern University research group improve our understanding of everything from the internet to human disease.

Now Barabási and colleagues are using networks to learn more about the way we eat. In a paper published in Scientific Reports, Barabási’s research team posed the question:

“Are there any quantifiable and reproducible principles behind our choice of certain ingredient combinations and avoidance of others?”

In particular, the researchers call the food pairing hypothesis into question. First imagined in 1992 by chefs Heston Blumenthal and François Benzi, the food pairing hypothesis states that ingredients will work well together in a dish if they share similar flavors. Following this logic, chefs have come up with crazy new food combinations like Blumenthal’s infamous concoction of white chocolate and caviar.

Thanks to the efforts of food scientists around the world, we now have extensive information available about the many chemical compounds responsible for giving different foods their distinctive smells and tastes. Armed with this information, Barabási’s team created the flavor network, a giant web of ingredients linked by their shared flavor compounds.

The backbone of the flavor network. Each node represents a different ingredient, where the size of the node represents the ingredient’s prevalence in a variety of recipes. The thickness of a line between two nodes reflects the relative number of flavor compounds shared by the two ingredients.

Just as the food pairing hypothesis would predict, the researchers found that North American and Western European cuisines indeed favor ingredient combinations with many shared flavor compounds. The researchers also found, however, that East Asian and Southern European cuisines tend to avoid pairing ingredients with shared flavor compounds. Soy sauce, scallions, and sesame oil, for example, share hardly any flavor compounds but are commonly combined in East Asian cuisine.

These unexpected findings fundamentally question our previous notion of flavor pairing. Although the food pairing hypothesis still holds for some cuisines, it appears there are many more desirable flavor combinations available than previously imagined. As researchers continue to examine a wider variety of ingredients and cuisines, we will be able to build even larger, more robust flavor networks to gain insight into the fundamental principles behind our ingredient pairing preferences.

Such flavor networks will also benefit the next generation of “creative” computers. By combining our current knowledge of flavor networks with computer learning, scientists at IBM are now creating adaptive computer systems that will “learn” to create desirable and innovative food combinations. One day, these computers could help create better school lunches or design menus that meet strict dietary restrictions without sacrificing great flavor.

Of course, there’s more to cooking than lists of flavor compounds and networks of ingredients. Factors like color and texture can have play equally important roles in the palatability of a dish. It therefore seems unlikely that a computer will ever be able to replace the creativity and aesthetic prowess of human chefs. But then again, did anyone expect a computer to win Jeopardy?


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.

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