Scientific names matter to marketability: A taste test of infusions of a native Florida holly
(Ilex vomitoria) and yerba mate (I. paraguariensis)
Alisha E. Wainwright* and Francis E. Putz
Department of Biology
University of Florida
Gainesville, FL 32611, USA
*Corresponding author; email: [email protected]
In preparation for: Dr. Mark Rieger, Associate Dean of College of Agricultural and Life
Sciences and later submission for publication in Economic Botany
Keywords: yerba mate, yaupon, taste perception, nomenclature, infusion
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Abstract
Yerba mate (Ilex paraguariensis) and yaupon holly (I. vomitoria) infusions are caffeine- containing and offer rich cocktails of antioxidants. Yerba mate is widely consumed in its native region of northeast Argentina, Paraguay and southwest Brazil. In contrast, a tea made from yaupon a holly native to the Southeastern USA, enjoyed only a flurry of market attention in the early 1800s before falling into obscurity. Some historians suggest that yaupon’s decline in popularity resulted in part from its scientific name, which is based on its traditional Amerindian religious rituals that included ceremonial vomiting and not on it containing any emetic properties. We evaluated how taste preferences and botanical nomenclature are likely to affect the market for yaupon holly tea if it were made commercially available. Two samples of yaupon were prepared by oven roasting and crushing the leaves with or without small twigs; the yaupon brews were compared with twig-free and twig-containing commercially available brands of yerba mate. Panelists significantly preferred yaupon holly with and without twigs over yerba mate, and yerba mate with stems over pure leaf yerba mate (for all comparisons, P <0.05). The highest ranked infusion was pure leaf yaupon tea. If a participant had consumed yerba mate prior to the experiment, they were more likely to consider purchasing yaupon tea. Although the majority of panelists reportedly preferred yaupon to yerba mate, many reported that the former’s scientific name and history would reduce the likelihood of their purchasing yaupon.
Introduction
Psychoactive plants are used by humans to increase social connections, to boost energy levels, and as entheogens (any substance taken to bring on a spiritual experience). With over a trillion cups of caffeinated beverages consumed each year (Klosterman 2006), caffeine is arguably the worlds most frequently consumed psychoactive substance. Exploration of other
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caffeine sources seems warranted due to the increase of caffeine consumption. Given the many negative environmental and social effects of cultivation, processing, transporting, and marketing of tea and coffee (O'Brien and Kinnaird 2003; 2004), exploration of alternative and local sources that could alleviate stresses on developing countries seems warranted. For example, although coffee contributes to Brazil’s economy, the coffee industry and the jobs it brings are implicated in higher levels of school withdrawals (Kruger 2007). Finding a caffeine alternative that is locally abundant and easily cultivated could reduce this and other negative impacts of coffee and tea production.
In addition to increasing global markets for caffeine-containing products, consumers are increasingly aware of the health benefits of diet-derived antioxidants. Red grapes, citrus, soybeans, and blue berries are well known examples of foods rich in flavanoids and other antioxidants (Beecher 2003), but others are not widely recognized, which is a barrier to efforts to increase consumption of antioxidants (Toner 2004). A caffeine-containing species that grows in the United States and that also contains substantial anti-oxidation potential would seem to provide an ideal commercial and conservation opportunity.
Research on Ilex paraguariensis (yerba mate) and I. vomitoria (yaupon holly) confirm that infusions made from the leaves and small twigs of these plants are rich in both caffeine and antioxidants (Campos et al. 1996; Reginatto et al. 1999; Bastos 2006; Palumbo et al. 2007;
Palumbo et al. 2009). Yerba mate markets are booming globally whereas yaupon consumption has not been widespread in its native range in the Southeastern USA since the mid 1800s.
Unfortunately, this contrast has not been explored by researchers. Also, there have been no efforts made to examine taste perception of yaupon holly tea or its commercial viability given its scientific name and historical uses among Amerindians. In this paper we examine how taste and
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botanical nomenclature affect consumer likelihood to purchase healthful yaupon holly tea if it were made commercially available.
Yaupon holly
Yaupon holly is common both in the wild and as an ornamental shrub in the Southeastern
United States (Hudson 1979). Amerindians, early European colonists, and African Americans consumed an infusion made from the leaves and stems of yaupon holly. William Aiton named I. vomitoria after cultivating it in his garden at Kew, even though he never traveled to North
America. Aiton credited Mark Catesby for discovering the plant in Florida in 1700. Yaupon’s scientific name derives from Amerindian religious rituals that included fasting, binge drinking, and ceremonial vomiting as a means of purification before a momentous occasion such as warfare. Catesby incorrectly described yaupon as an emetic (Blanton 1931); chemical research revealed no emetic properties in yaupon (Fuller et al. 2002). Infusions of yaupon were often called south sea tea, cassina, and black drink (Hale 1892; Hudson 1979). Dried leaves were exported and marketed in Europe under the name of “Appalachina.” Many botanists confused I. vomitoria with I. cassine as the source of the famous “black drink,” but recent findings suggest that caffeine and other methylxanthine alkaloid contents are especially high in I. vomitoria, so it is the best-supported source of yaupon tea (Edwards and Bennett 2005).
The so called “black drink” was prepared by heavily steeping the leaves and stems of yaupon in water over an open flame for several hours until all the caffeine was removed, the acidity increased, and most of the liquid had evaporated, leaving the tea a dark black color, hence its name (Hudson 1979). This heavy infusion was not the form in which it was consumed daily by colonists, who often compared the taste of yaupon holly tea to that of Asian teas (Camellia sinensis) (Hudson 1979). Some speculate that yaupon holly tea consumption and exportation
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declined due to economic pressures from tea and coffee tradesmen (Hudson 1979). During the
Civil War, yaupon consumption increased again in the South when economic conditions and blocked trade routes inhibited the importation of coffee and tea. Despite the spike in consumption, yaupon usage as a beverage declined in popularity after the war. A few years later, as resident Amerindians were moved to reservations in Oklahoma, yaupon tea consumption slowly became déclassé and disappeared by the mid 1800s (Hale 1891).
There have been sporadic attempts to resurrect the yaupon tea business. In the early
1920s the United States Department of Agriculture (UDSA) conducted caffeine experiments and distributed hot cassina tea at the Charleston County Fair, but the tea did not catch on
Yerba mate
Yerba mate is native to South America and is grown commercially in northeast
Argentina, Paraguay, and southwestern Brazil (Santa Cruz et al. 2002). An infusion of yerba mate toasted leaves, small twigs, and water (hot or cold) is regularly consumed by many South
Americans (Anonymous 1998). Like yaupon holly, yerba mate apparently started out as a medicinal and ritual drink. The Guarani people of Paraguay introduced Spanish missionaries to yerba mate and its preparation methods in the early fifteenth century (Moreau de Tours 1904).
Spaniards and Jesuit missionaries embraced and promoted the beverage. Whereas yaupon holly tea consumption has virtually disappeared in North America, 169 thousand tons of yerba mate was consumed in Argentina alone in 1998 (Santa Cruz et al. 2002); Argentina is now the largest producer of yerba mate in the world (Odarda 2007).
Yerba mate is a social drink and each South American country prepares it differently.
The principal variations are in the percentage of twigs and leaves, how finely the mixture is ground, and the bitterness of the infusion (Calviño et al. 2005). Typically the higher the leaf to
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stem ratio is, the more expensive the product. A variety is defined as “with stems”, if there is a minimum of 65% leaves and the remaining 35% stems, whereas “pure leaf” yerba mate must have a minimum of 90% leaf material (Anonymous, 1998).
Consumers generally use half a liter of water for every 50 g of plant material, but yerba mate is also widely brewed with tea bags, French presses, or as mate cocido, which all require less plant material than the traditional gourd and bombilla method (Odarda 2007). The use of tea bags is apparently a concession to Asian tea drinkers. Traditionally, the beverage was steeped and served at approximately 70 °C in a gourd and sucked through a filtered straw (Ramallo et al.
1998). Initial sips of yerba mate are extremely bitter, but water may be repeatedly poured over the same mixture, decreasing its bitterness (Calviño et al. 2005).
According to the Argentine Ministry of Economics and Production (2007), the USA is the fifth highest consumer of yerba mate, importing 83 tons from Argentina in March 2007 alone. The merits of mate are increasingly recognized in the USA where it is advertised as having antioxidation potential, aiding in disease prevention, providing energy, and aiding in weight loss. Traditional manufacturing of yerba mate includes several steps after leaf collection including quick heating of the leaves to 350–450 °C for 2 minutes presumably to stop enzymatic activities (Tonon and Marucci 1995). After cooling the leaves are dried in circulating air at 110
°C for 4 h, crushed, placed in paper or mesh bags, and stored at room temperature for approximately 9 months at ambient temperatures and humidities or at 50–60°C with 60% relative humidity for approximately 6 weeks (Schmalko et al. 1999). The final product is milled and packaged before shipping.
Why yaupon holly declined into obscurity while markets for yerba mate thrived remains unclear, but comparing the taste of yaupon with yerba mate and examining the effect of
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botanical nomenclature and history on purchasing habits seem justified given the potential of yaupon as a natural caffeine and antioxidant source. Given that there is a market for yerba mate in the USA, if participants prefer yaupon to yerba mate then there is increased likelihood of product acceptance. Certainly if consumers do not like the taste of yaupon holly tea, they will not purchase it. Hudson (1979) suggested that another attempt at commercial exploitation of yaupon should utilize the preparation methods and traditions of yerba mate, instead of using Asian tea brewing methods. With increased interest in yaupon flavonoids and other antioxidants, it seems important to understand consumers taste perceptions of yaupon infusions, especially since preparation methods and leaf concentrations affect not only taste, but also caffeine and antioxidant contents.
Methods
Plant material
Leaf-bearing branches of yaupon holly were collected from randomly selected shrubs in natural areas on the University of Florida campus in Gainesville, Florida, USA (29º39’N,
82º19’W). Using the standard methods for preparing yerba mate (Power and Chestnut 1919;
Tonon and Marucci 1995), we prepared two sorts of yaupon infusion, one with twigs and the other without. Twigs <2 mm diameter were separated from leaves and all plant material was air dried for 24 hours prior to flash heating at 350°C for 2 min. After cooling the material to room temperature, it was oven dried at 110˚C for 4 hours and then at 80°C for 48 hours. After drying, the plant material was crushed by hand into pieces about 2 mm in diameter. The leaf material was then cured in a humid greenhouse at 20-50°C for 8 days. Two yerba mate brands from plant material grown in Argentina were used for this experiment; one variety manufactured by
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EcoTeas was “pure leaf” mate and the other, manufactured by Cruz de Malta, was classified as
“with twigs.”
Tea preparation
Participants were given the four infusions to taste (two of yaupon and two of yerba mate both with and without twigs). The yaupon holly leaf-stem infusion had a 65% leaf to stem ratio.
The pure leaf yaupon sample had 90% leaf-to-stem ratio. All samples were prepared by steeping
50 g of dry material per liter of 70 ˚C purified drinking water for five minutes (Kawakami and
Kobayashi 1991). Samples were prepared 15 min before being served to the taste panelists; solids were strained out and the samples were kept at 50˚C throughout the tests.
Survey design
Participants were given a 12-item questionnaire after the taste test (Appendix 1). Initial questions assessed demographic information (sex and age). Participants were told that “yaupon holly is a caffeine-containing ornamental shrub that is native to Florida and adjacent states. A stimulating tea made from the leaves and stems from this plant was consumed by Amerindians and early European colonists.” They were then asked, “would you purchase this beverage if it was made commercially available?” The next series of questions identified imbibers of yaupon tea and yerba mate and how regularly they consumed each type of infusion. Participants who indicated that they consumed yerba mate regularly were asked to define what type of yerba mate they prefer (Brazilian style, Paraguayan style, Argentinean style, or others). All participants were then told that the scientific name for yaupon holly is Ilex vomitoria and were informed of its association with Amerindian religious rituals. They were explicitly informed that there is nothing in yaupon tea that induces vomiting and asked if knowing its former usage would negatively affect whether they would purchase this beverage if it were made commercially available.
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Hedonic regression was used to examine differences between samples using Compusense Inc software.
In compliance with the university's Institutional Review Board for Behavioral/NonMedical
(Institutional Review Board number IRB00000336), potential participants were informed of the study protocol after which, those willing to participate, anonymously completed the taste assessment and questionnaire.
Results
Demographics
Of the 75 panelists, 32 were male, 43 were female, 73 were between the ages of 18 and
29, one was between the ages of 45-65, and one was over the age of 65.
Taste Preferences
Three participants had consumed yaupon within the last year and 13 participants had consumed yerba mate. Of those that had consumed yerba mate, four consumed it regularly (more than once a month), and the rest (n = 8) consumed it twice a year or less. These panelists either consumed Argentine style (n = 6), Brazilian style (n = 1), or they did not know what style they had consumed (n = 6). Panelists significantly preferred yaupon holly with and without stems over any form of yerba mate, and yerba mate with stems over pure leaf yerba mate (P <0.05); preferences for different varieties of yaupon holly and yerba mate with stems did not vary (Table
1). Median values for yaupon with stems, yaupon without stems, and yerba mate with stems were
“dislike slightly” and the median value for yerba mate pure leaf was “moderately dislike.”
When asked if they would purchase a caffeine-containing tea from made from the leaves of a shrub native to North America that was consumed by Amerindians and early European colonists, 16% (n = 12) said yes and 84% (n = 63) said no. Of the 12 that would consider
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purchasing yaupon, 42% (n = 5) said that yaupon holly’s scientific name and its ritualistic history would reverse their decision to purchase. Twenty five (n = 3) percent of those that had previously consumed yerba mate said they would purchase yaupon tea if it were made commercially available, which is higher than the overall percentage of participants likelihood to purchase yaupon. Those that consider themselves regular mate drinkers preferred the mate varieties over the yaupon varieties (Table 2).
Forty one percent (n = 31) of participants gave pure leaf yaupon a rating higher than 4 compared to 19 (n = 14) who gave pure leaf yerba mate a rating higher than 4 (Figure 1). Only
28% (n = 21) and 24% (n = 18) ranked pure leaf yaupon and yaupon with stems higher than 4, respectively.
Discussion
The initial preference of taste testers for infusions of yaupon over yerba mate suggests the potential marketability of yaupon as a tea. Given that there was no difference in taste preference for yaupon infusions with or without twigs, apparently either blend should be viable. In contrast, the tasters preferred twig-containing yerba mate over pure leaf yerba mate, perhaps because the latter is more bitter (Calviño et al. 2005).
While yaupon was preferred over yerba mate, on average the former was still classified as “slightly disliked” and tasters reportedly were unlikely to purchase it. The likelihood of purchase declined even more after participants learned yaupon’s scientific name and about its historical use. Those who had previously consumed yerba mate were more likely to want to purchase yaupon, but those that considered themselves regular yerba mate drinkers preferred mate to yaupon in taste. Given that almost 60% of those that considered purchasing yaupon were
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put off by its scientific name, future promotion of this plant product may be severely impeded by its name.
The lack of panelist involvement in the preparation of the infusions may have influenced the results of this experiment. At least in the case of yerba mate, the social aspects of preparation and consumption are essential to its use in South America; eliminating that element from the experiment could alter taste perceptions and preferences (Hudson 1979). Also, only one method of tea preparation was considered. In addition to roasting the leaves, the leaves and stems may also be smoked, dried for longer periods, or the concentration of twigs could be increased.
Palumbo et al. (2009) concluded that caffeine concentrations in yerba mate (0.65–0.85%) are comparable with yaupon (Mazzafera 1994; Reginatto et al. 1999) and that future studies should address the influences that processing and preparation method may have on the flavor and caffeine concentration of yaupon tea.
Given that the history of yaupon has included what are to many potential consumers strange rituals that are captured in its scientific name, there is good reason to believe that the species will never amount to anything more than an ornamental shrub. Results from our study suggest that although consumers may appreciate yaupon tea’s taste more than yerba mate, botanical nomenclature and plant history affects the likelihood of purchase, even when the product is a local, native, organic, wild-grown caffeine-containing alternative to imported tea and coffee.
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Samples X SD Significantly different Yaupon holly “with stems” 3.91 2.09 yerba mate “pure leaf” Yaupon holly “pure leaf” 4.09 2.03 yerba mate “pure leaf” Yerba mate “with stems” 3.63 1.92 yerba mate “pure leaf” Yerba mate “pure leaf” 2.88 1.73 no difference Table 1. Mean, standard deviation, and significance (at the 0.05 level) of preference for the infusions when ranked on a 9-point Likert scale from 1 for strongly dislike to 9 for strongly like for all participants (n = 75).
Samples X SD Yaupon holly “with stems” 5.75 2.63 Yaupon holly “pure leaf” 4.00 1.63 Yerba mate “with stems” 7.00 0.82 Yerba mate “pure leaf” 6.75 1.25 Table 2. For regular consumers of yerba mate (n = 4), mean and standard deviation of preferences for the infusions when ranked on a 9-point Likert scale from 1 for strongly dislike to 9 for strongly like.).
Figure 1. Percentage of participants that rated infusions higher than
4 on the Likert scale of 1 (strongly dislike) to 9 (strongly like).
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Palumbo, M.J., S.T. Talcott, and F.E. Putz. 2007. Nitrogen fertilizer and gender effects on the secondary metabolism of yaupon, a caffeine-containing North American holly. Oecologia
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Appendix 1 Today's Sample:
Caffeinated Beverages
To start the test, click on the Continue button below:
Question # 1.
Please indicate your gender.
Male Female
Question # 2.
Male: Please indicate your age range.
Under 18 18-29 30-44 45-65 Over 65
Question # 3.
Female: Please indicate your age range.
Under 18 18-29 30-44 45-65 Over 65
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Take a bite of cracker and a sip of water to rinse your mouth.
Remember to do this before you taste each sample.
WHEN ANSWERING ANY QUESTION, MAKE SURE THE NUMBER ON THE CUP MATCHES THE NUMBER ON THE MONITOR.
Please click on the 'Continue' button below.
Question # 4.
Please indicate how much you like or dislike the samples listed below.
Taste
Sample <
1 2 3 4 5 6 7 8 9
Sample <
1 2 3 4 5 6 7 8 9
Sample <
1 2 3 4 5 6 7 8 9
Sample <
1 2 3 4 5 6 7 8 9
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Yaupon holly is a caffeine-containing ornamental shrub that is native to Florida and adjacent states.
A stimulating tea made from the leaves and twigs from this plant was consumed by Amerindians and early European colonists.
Please Click the ' Continue' Button Below
Question # 5.
Would you purchase this beverage if it was made commercially available?
Yes No
The scientific name for yaupon holly is Ilex vomitoria. The name comes from the tea’s association with Amerindian religious rituals that included fasting, binge drinking, and ceremonial vomiting.
However, there is nothing in yaupon tea that induces vomiting (i.e, it has no emetic compounds).
Please Click the ' Continue' Button Below
Question # 6.
Would knowledge of its former use negatively affect whether or not you would purchase this beverage if it was made commercially available?
Yes No
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Question # 7.
Have you ever consumed yaupon tea prior to this experiment?
Yes No
Question # 8.
How often do you consume yaupon tea?
More than once a day Once a day 2-3 times a week Once a week 2-3 times a month Once a month Twice a year Once a year Less than once a year
Question # 9.
Have you ever consumed yerba mate prior to this experiment?
Yes No
Question # 10.
How often do you consume Yerba Mate?
More than once a day Once a day 2-3 times a week Once a week 2-3 times a month Once a month Twice a year Once a year Less than once a year
Question # 11.
What type of yerba mate do you normally consume?
Brazilian style Paraguayan style Argentinean style Uruguayan style Other 20
Question # 12.
Using the keyboard located in the tray under the counter, please name the other style of yerba mate you consume.
______
______
______
The test has ended.
DO NOT click continue on the next screen.
Please lift your window to let the server know you have finished.
Thank you and come back tomorrow.
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