Phytochemical and Antioxidant Potential of Herbal Teas

Food and Nutrition Sciences, 2017, 8, 1039-1049

http://www.scirp.org/journal/fns

ISSN Online: 2157-9458

ISSN Print: 2157-944X

DOI:

10.4236/fns.2017.811076 Nov. 30, 2017 1039 Food and Nutrition Sciences

A Comparison of Selected Phytochemical and

Antioxidant Potential of Two Tea Beverages

Shantrell Willis, Martha Verghese, Meijah McCollum, Kabreshia Cheatom, Zaquavis Willis,

Kevon Seay, Rajitha Sunkara, Lloyd Walker

Department of Food and Animal Sciences, Alabama Agricultural and Mechanical University, Normal, Al, USA

Abstract

Herbal teas have been used as medicinal aids for centuries to treat a myriad of

illnesses and have also been suggested to function in chemoprevention. Ha

ing numerous phytochemicals, the purported health benefits of herbal teas

may be due to their antioxidant potential. Herbal tea blends infused with

spices are increasing in popularity in U.S., and preliminary studies suggest the

synergistic effects of combining herbal teas and spices. Some teas that are i

creasing in popularity include raspberry leaf, strawberry leaf, and hibiscus.

The objectives of this study were to determine the antioxidant capacity of tea

beverages (herbal (HT) (functional yogurt-based beverage-

new product) and

Chai (CT) (store bought) and to determine consumer preferences of tea bev

rages (HT and CT). Total phenolic content (TPC), total flavonoid content

(TFC), free radical scavenging activity by 1,1-diphenyl-2-picry

hydrazyl

(DPPH), trolox equivalent antioxidant capacity (TEAC) and ferric reducing

antioxidant power (FRAP) were evaluated in methanolic and aqueous bev

rage extracts. A functional yogurt-

based beverage (HT) was developed and

sensory analysis was also conducted using a 5-

point hedonic scale comparing

consumer preference of HT or CT beverages. The highest phenolic content

was observed in CT aqueous extracts (AQ) (500

mg GAE/g), all other extracts

had significantly (

≤ 0.05) lower phenolic content. CTAQ had

significantly

(

≤ 0.05) higher flavonoid content compared to all other extracts (1.7

CAE/g). The highest DPPH radical scavenging activity was observed in HT

methanolic extracts (ME) (44.48% inhibition). The lowest DPPH radical sc

venging was observed i

n HTAQ (21.88% inhibition). Approximately 61% of

sensory panelists gave the yogurt-

based developed product a rank of 4 or

greater (on a 5-

point hedonic scale) with 41% of panelists preferring the HT

beverage over CT beverage. The results of this study suggest that a combin

tion of herbal teas and spices may benefit consumers by improving their ant

oxidant status and may have potential as a functional-beverage.

How to cite this paper:

Willis, S., Verghese,

, McCollum, M., Cheatom, K., Willis,

Z.,

Seay

, K., Sunkara, R. and Walker, L. (2017

)

A Comparison of Selected Phytochemical

and Antioxidant Potential of Two Tea Bev

rages

Food and Nutrition Sciences

1039

-1049.

https://doi.org/10.4236/fns.2017.811076

Received:

September 15, 2017

Accepted:

November 27, 2017

Published:

November 30, 2017

7 by authors and

Scientific

Research Publishing Inc.

This work is licensed under the Creative

Commons Attribution International

License (CC BY

4.0).

http://creativecommons.org/licenses/by/4.0/

Open Access

S. Willis et al.

DOI:

10.4236/fns.2017.811076 1040 Food and Nutrition Sciences

Keywords

Antioxidant, Functional Food, Beverage, Herbal Tea, Sensory

1. Introduction

Traditional and herbal teas have been consumed for centuries, not only for their

taste, but as disease preventing agents. Traditional tea, derived from the plant

Camellia senesis,

is the most widely consumed beverage in the world next to wa-

ter [1] and market research also suggests that herbal teas are increasing in popu-

larity in recent years. Derived from plants other than the

Camellia senesis

, herbal

teas have been utilized for centuries for their medicinal properties. Studies sug-

gest a positive correlation between herbal tea consumption and the reduction of

select chronic diseases. Some health benefits that are associated with herbal teas

include anti-cancer, hypotensive, anti-diabetic, and anti-mutagenic properties;

which have been attributed to the presence of antioxidative phytochemicals [2]

[3]. In recent years, the market has experienced an increase in purchases of tea

and beverages containing tea (ex. Smoothies, juices). The ready to drink sector is

the largest of soft drink production [4]. With less than 1% of the total food and

drink market accounting for functional foods [5], consumers are continually

searching for functional beverages with added benefit.

The consumption of smoothies and other yogurt based products is also on the

rise in the U.S. With a 40% production increase within one year [6], yogurt con-

tains probiotics and bioactive antioxidants from dairy; both of which can have

beneficial effects on the consumer [7] [8]. Research suggests the synergistic ef-

fects of probiotics and antioxidants in the prevention or elimination of some

chronic diseases [9].

Though there are few yogurt-based tea beverages on the market currently,

there is still a need for more herbal tea based beverages and herbal tea blends to

provide higher amounts of antioxidative phytochemicals to consumers. Some

herbal teas that are increasing in popularity in the U.S. are raspberry leaf, straw-

berry leaf, and hibiscus teas. Tea blends are also often infused with spices for

improved taste and increased positive effects on health, including the prevention

of some chronic diseases such as cancer. Cinnamon, fenugreek, fennel seed and

cardamom, are select spices that have been associated with health benefits but

are under-utilized in the U.S.

Studies suggest the health benefits of strawberry leaf may be correlated with

the high antioxidant capacity of the plant’s extracts. Some reported health bene-

fits of strawberry leaves include, anti-diarrhea, vasodilator, and antimicrobial ef-

fects [10]. Studies conducted have suggested the health benefits of raspberry

leaves including, but not limited to anti-inflammatory, antiseptic, anti-diarrheic,

and gastrointestinal relief [11]. Also known as sorrel, bissap, or sour tea, hibiscus

S. Willis et al.

DOI:

10.4236/fns.2017.811076 1041 Food and Nutrition Sciences

is one of the more common herbal teas incorporated into tea blends in the U.S.

[12]. A number of research efforts suggest the many health promoting properties

of hibiscus including anti-hypertensive [12], hypo-cholesterolemic [13], antimi-

crobial and anti-cancer [14], effects.

Epidemiological studies suggest a reduction in the risk of chronic diseases,

such as colon cancer, in populations with high consumption of plant foods con-

taining phytochemicals [15]. The chemical components found in raspberry leaf

(ellagic acid), strawberry leaf (quercitin), hibiscus (coumarin), cinnamon (cin-

namic acid), fenugreek (trigonelline), fennel seed (rutin), and cardamom (euge-

nol) are reported to have anti-diabetic and anti-inflammatory potential; howev-

er, there are few ready-to-drink RTD beverages on the market that are com-

prised of these teas and spices. The consumption of RTD tea beverages has in-

creased with the global tea market being almost 400 billion liters, it is estimated

that RTD tea beverages will continue to grow [4].

The use of supplements and RTD tea beverages is constantly increasing. Be-

cause of this, there is a possible niche in the market for more beverages that in-

corporate spices and herbal teas. Though there are few yogurt-based tea beve-

rages on the market currently, there is still a need to develop more beverages of

the like and to evaluate the antioxidant capacity of the beverages to correlate the

possible health benefits to consumers.

The objectives of this study were to determine the antioxidant capacity of tea

beverages (herbal (HT) (functional yogurt-based beverage—new product named

Zalamero) and Chai (CT) (store bought))) by evaluating total phenolic content

(TPC), total flavonoid content (TFC), DPPH radical scavenging, ferric reducing

antioxidant power (FRAP), and trolox equivalent antioxidant capacity (TEAC)

and to determine consumer preferences of HT and CT via sensory analysis.

2. Materials and Methods

2.1. Acquisition of Experimental Materials

All chemicals were obtained from Sigma Chemical Company, St Louis, Mo. and

Fisher Scientific Company, Waltham, Mass. Raspberry leaf, strawberry leaf, and

hibiscus leaf teas were purchased from Monterey Bay Spice Company (Watson-

ville, CA). Fenugreek, cinnamon, fennel, and cardamom were purchased from a

local food market. Chai tea beverage was obtained from a local market.

2.2. Development of Beverages

Chemical and sensorial analysis was conducted on the HT and CT beverages.

The HT beverage was developed on the campus of Alabama Agricultural and

Mechanical University. The formulation (

Table 1) comprises of strawberry leaf,

raspberry leaf, and hibiscus teas, and spices fennel seed, fenugreek, cardamom,

cinnamon, yogurt, inulin, agave and frozen strawberries.

The CT beverage was obtained from a local market and contained green tea

extract and soy protein isolate among other ingredients.

Overview

Phytochemical and Antioxidant Potential of Herbal Teas

Phytochemical and antioxidant potential of herbal teas is explored in this study, focusing on the comparison between a functional yogurt-based herbal tea beverage and a store-bought chai tea. The research evaluates total phenolic content, total flavonoid content, and antioxidant activities using various assays. Results indicate that the chai tea exhibits higher phenolic and flavonoid content, while the herbal tea shows significant DPPH radical scavenging activity. Consumer preferences were assessed through sensory analysis, revealing a notable preference for the chai tea among participants. This study highlights the health benefits associated with herbal teas and their potential as functional beverages. Key Points Compares antioxidant capacity of herbal tea and chai tea beverages. Ev…

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FAQs

What are the main findings regarding antioxidant capacity?

The study found that the chai tea beverage exhibited significantly higher total phenolic content and total flavonoid content compared to the herbal tea beverage. Specifically, the chai tea's aqueous extracts showed a total phenolic content of 523.03 GAE/g, while the herbal tea's methanolic extracts demonstrated notable DPPH radical scavenging activity, achieving up to 44.48% inhibition. These results suggest that the chai tea may offer greater antioxidant benefits, which are crucial for health promotion.

How does the sensory analysis reflect consumer preferences?

Sensory analysis conducted with 43 panelists revealed that 59% preferred the chai tea beverage over the herbal tea beverage. The panelists evaluated attributes such as flavor, mouthfeel, and overall acceptance using a 5-point hedonic scale. Comments indicated that the chai tea's milder spice flavor was more appealing, while some found the herbal tea's flavor profile to be 'too spicy.' This highlights the importance of flavor in consumer acceptance of functional beverages.

What phytochemicals were analyzed in the study?

The study focused on several key phytochemicals found in herbal teas, including phenolic compounds and flavonoids. These compounds are known for their antioxidant properties and potential health benefits, such as anti-inflammatory and anti-cancer effects. The research specifically measured total phenolic content and total flavonoid content in both the herbal tea and chai tea beverages, providing insights into their respective health-promoting qualities.

What methods were used to evaluate antioxidant activity?

Antioxidant activity was evaluated using several established methods, including DPPH radical scavenging, ferric reducing antioxidant power (FRAP), and trolox equivalent antioxidant capacity (TEAC) assays. These methods allow for a comprehensive assessment of the beverages' ability to neutralize free radicals, which is essential for understanding their potential health benefits. The results from these assays indicated varying levels of antioxidant capacity between the herbal tea and chai tea.

What are the implications of the study for functional beverages?

The findings of this study suggest that herbal teas, particularly when combined with functional ingredients like yogurt, can provide significant health benefits due to their antioxidant properties. The research indicates a growing market potential for functional beverages that incorporate herbal teas and spices, as consumers increasingly seek products that contribute to health and wellness. This could lead to the development of new beverage formulations that cater to health-conscious consumers.