The ides of October have passed, and Halloween nears, promising with it pillow cases of sucrose, crisp flannel temps, spooky pumpkins, and my favorite of all… fresh apples. The forbidden fruit. Honeycrisps, Fujis, Galas, Empires – I love ‘em all (not you Red Delicious).

In honor of apple season, and my formative years in an apple-cropping region of New York State, we will embark on an exploration of the ultimate tea to pair with apple. That’s right – bite an apple, then sip some tea, or perhaps even sip then bite – but the two flavors must promenade the palette together.

Our goal here is to explore the flavor profile of apple (Malus domestica) according to its known aroma and taste characteristics, then see which tea (Camellia sinensis) type might provide the best companion for this gallant fruit.

First, it’s important to note that foods and beverages ‘pair well together’ when they have overlapping flavor qualities – red meat and Cabernet Sauvignon, lobster and oaked Chardonnay, Dorito Crunch-wrap Supreme and Baha blast. The key is to match.

‘Flavor’, as we discuss it here, is divided into two components – taste (sweet, salty, bitter, sour, savory) and aroma (far more complex than taste, and includes several hundred types).

In order to identify the tea with taste and aroma characteristics of greatest similarity with an apple, we will survey peer-reviewed food science literature that has examined the predominant flavor qualities of apple, then examine tea science literature until we uncover the tea of maximal overlap with M. domestica. Let’s get apple it (many more apple puns on the way – I got a little ex-cidered).

Regarding taste – sweet and sour are the dominant apple-type qualities. Apple taste is determined primarily by the balance, or ratio, between apple sugars (mostly sucrose, glucose, and fructose) and apple acids (namely malic acid – In fact malic acid is named after apple (genus Malus)) [1].

Aroma is more complex. Among the 350 volatile fragrance compounds (or VFCs – small floating aroma particles that travel through air into your nose) emitted by apple fruit [2], about 20 VFCs are considered key components of apple aroma [3].

VFCs can generally be broken down into a limited number of major VFC categories; alcohols, esters, aldehydes, ketones, ethers, etc. [4]. As apples mature and ripen, the aroma profile shifts from VFCs of the aldehyde category towards VFCs of the ester category [5, 6]. This transition from aldehydes to esters during apple maturation forms the fragrant, flowery, apple-sweet aroma of fresh ripe apple [7].

In fact, apple esters, including butyl acetate, hexyl acetate, and 2-methyl-butyl acetate [8], can account for over 80% of all aroma-relevant substances in fresh apple [9]. Fresh Fuji apples, for example, contain two ester-type VFCs that dominate the Fuji apple aroma profile [10]. Lastly, beta-damascenone is a non-ester VFC that plays an important role in apple aroma [11].

In summary: the ratio of sugars to malic acid determines taste (sweet vs. sour), while various ester-type VFCs increase through apple ripening to create the characteristic apple-sweet appley-ness of apple aroma.

Great – now that you’re feeling Appley (Wu Mountain Word of The Day), let’s ponder tea flavor. I would love to find a tea that’s sweet with a touch of sour (perhaps with some… malic acid?), plus an ester-dominated aroma profile with a dash of beta-Damascenone peppered in.

One tea science article I love to reference is that of Wang et al. [12] that used the same batch of raw tea leaves to process the 6 major tea types (green, oolong, yellow, white, black and dark). Re-examining this article, I found that black tea processing caused malic acid levels to increase by 35% compared with raw untouched tea leaves (point for black tea).

What’s more, sweet-tasting compounds found in black tea include glucose and fructose [13], which are critical agents of sweetness in ripe apple. Thearubigans, a black tea-specific polyphenol, confers additional sweetness to black tea infusions [14], helping to create an appley-er ratio of sweet and sour taste components (point for black tea).

Now aroma. Much like apple fruit ripening, during Oolong bruising, aldehydes gradually decrease while fruity ester compounds gradually increase (point for Oolong) [15, 16]. Meanwhile, beta-damascenone concentration in tea leaves increases significantly due to enzymatic oxidation, the central process involved in black tea production, making beta-D a characteristic aroma component in black tea infusions (point for black!) [17].

Lastly, ester-type VFCs are particularly abundant in black tea [18] compared with Oolong or Green teas. Check out the figure below taken from a study by Shi et al. [19].

I’m calling it here folks – Black tea wins! The organic sugar to malic acid ratio resembles apple more than other tea types. Beta-damascenone and ester-type aroma compounds are more abundant in black tea than other tea types, giving it the most APPLEY aroma profile. Hey, I mean the colors of ripe apple and infused black tea even look alike. Winner winner, fritter dinner.

This was fun. Now go sink your teeth into a juicy fresh-plucked apple and wash it down with a big gulp of black tea.

Happy October! …

BOO!!

-Dylan

1.         American Society for Horticultural Science. and International Society for Horticultural Science., Horticultural reviews. AVI Pub. Co.: Westport, Conn.,. p. volumes

2.         Song, J. and C.F. Forney, Flavour volatile production and regulation in fruit. Canadian Journal of Plant Science, 2008. 88(3): p. 537-550.

3.         Dixon, J. and E.W. Hewett, Factors affecting apple aroma/flavour volatile concentration: a review. New Zealand journal of crop and horticultural science, 2000. 28(3): p. 155-173.

4.         Dimick, P.S., J.C. Hoskin, and T.E. Acree, Review of apple flavor — State of the art. C R C Critical Reviews in Food Science and Nutrition, 1983. 18(4): p. 387-409.

5.         Paillard, N., Flavour of apples, pears and quinces. Developments in food science, 1990.

6.         Mattheis, J.P., et al., Changes in headspace volatiles during physiological development of Bisbee Delicious apple fruits. Journal of agricultural and food chemistry, 1991. 39(11): p. 1902-1906.

7.         Tanaka, F., F. Hayakawa, and M. Tatsuki, Flavor and Texture Characteristics of ‘Fuji’ and Related Apple (Malus domestica L.) Cultivars, Focusing on the Rich Watercore. Molecules, 2020. 25(5): p. 1114.

8.         Schiller, D., et al., A dual positional specific lipoxygenase functions in the generation of flavor compounds during climacteric ripening of apple. Horticulture Research, 2015. 2(1): p. 15003.

9.         Altisent, R., et al., Lipoxygenase activity is involved in the regeneration of volatile ester-synthesizing capacity after ultra-low oxygen storage of ‘Fuji’apple. Journal of agricultural and food chemistry, 2009. 57(10): p. 4305-4312.

10.       Komthong, P., et al., Determination of potent odorants in apple by headspace gas dilution analysis. LWT – Food Science and Technology, 2006. 39(5): p. 472-478.

11.       Roberts, D.D., A.P. Mordehai, and T.E. Acree, Detection and Partial Characterization of Eight .beta.-Damascenone Precursors in Apples (Malus domestica Borkh. Cv. Empire). Journal of Agricultural and Food Chemistry, 1994. 42(2): p. 345-349.

12.       Wang, Y., et al., Impact of Six Typical Processing Methods on the Chemical Composition of Tea Leaves Using a Single Camellia sinensis Cultivar, Longjing 43. Journal of agricultural and food chemistry, 2018.

13.       Scharbert, S. and T. Hofmann, Molecular Definition of Black Tea Taste by Means of Quantitative Studies, Taste Reconstitution, and Omission Experiments. Journal of Agricultural and Food Chemistry, 2005. 53(13): p. 5377-5384.

14.       Li, S., et al., Black tea: chemical analysis and stability. Food & Function, 2013. 4(1): p. 10-18.

15.       Lin, S.Y., et al., Monitoring volatile compound profiles and chemical compositions during the process of manufacturing semi-fermented oolong tea. The Journal of Horticultural Science and Biotechnology, 2013. 88(2): p. 159-164.

16.       Liu, P.-P., et al., Flavor characteristics and chemical compositions of oolong tea processed using different semi-fermentation times. Journal of food science and technology, 2018. 55(3): p. 1185-1195.

17.       Ho, C.-T., X. Zheng, and S. Li, Tea aroma formation. Food Science and Human Wellness, 2015. 4(1): p. 9-27.

18.       Ho, C.-T., J.-K. Lin, and F. Shahidi, Tea and tea products: chemistry and health-promoting properties. 2008: CRC press.

19.       Shi, J., et al., Methyl Jasmonate-Induced Changes of Flavor Profiles During the Processing of Green, Oolong, and Black Tea. Frontiers in Plant Science, 2019. 10(781).