Crozier et al. Chemistry Central Journal 2011, 5:5
http://journal.chemistrycentral.com/content/5/1/5

RESEARCH ARTICLE

Open AccessCacao seeds are a “Super Fruit": A comparative
analysis of various fruit powders and products
Stephen J Crozier*, Amy G Preston, Jeffrey W Hurst, Mark J Payne, Julie Mann, Larry Hainly, Debra L Miller

Abstract
Background: Numerous popular media sources have developed lists of “Super Foods” and, more recently, “Super
Fruits”. Such distinctions often are based on the antioxidant capacity and content of naturally occurring
compounds such as polyphenols within those whole fruits or juices of the fruit which may be linked to potential
health benefits. Cocoa powder and chocolate are made from an extract of the seeds of the fruit of the Theobroma
cacao tree. In this study, we compared cocoa powder and cocoa products to powders and juices derived fromfruits commonly considered “Super Fruits”.
Results: Various fruit powders and retail fruit products were obtained and analyzed for antioxidant capacity (ORAC(μM TE/g)), total polyphenol content (TP (mg/g)), and total flavanol content (TF (mg/g)). Among the various
powders that were tested, cocoa powder was the most concentrated source of ORAC and TF. Similarly, dark
chocolate was a significantly more concentrated source of ORAC and TF than the fruit juices.
Conclusions: Cocoa powder and dark chocolate had equivalent or significantly greater ORAC, TP, and TF values
compared to the other fruit powders and juices tested, respectively. Cacao seeds thus provide nutritive value
beyond that derived from their macronutrient composition and appear to meet the popular media’s definition of a“Super Fruit”.

Background
Many popular press articles have deemed certain foods
as “Super Foods” due to a high purported nutritive
value. This trend has crossed over into numerous fruits,
fruit juices, and other fruit products wherein the highnutritive value is often based on the antioxidant capacityof these foods. Such fruits are commonly referred to as“Super Fruits” in popular media [1].
Cacao (or cocoa) beans are technically not beans orlegumes, but rather the seeds of the fruit of the
Theobroma cacao tree. The pod shaped fruit is botanically classified as baccate-like (berry-like) and each pod
produces approximately 35-50 seeds surrounded by asweet pulp [2]. The pod and the pulp surrounding the
cacao seed in this case constitute the fruit of cacao.
After harvest, cacao seeds and their surrounding fruit
pulp are typically placed in heaps or boxes and fermented under the influence of naturally occurring microbesthat multiply using the sugar from the pulp as an energy* Correspondence: scrozier@hersheys.com
The Hershey Center for Health & Nutrition, 1025 Reese Avenue, Hershey, PA,
17033, USA© 2011 Crozier et al

source. The seeds are then dried in the sun or in wood
fired ovens and shipped to cacao processors. Cacao
seeds next have their thin coats removed from theembryonic tissue, which is then roasted, and milled into
what is referred to as chocolate liquor. Cocoa powder is
produced by mechanically pressing most of the fat(cocoa butter) from the chocolate liquor and thus represents an extract of the cacao fruit’s seeds.
Cocoa powder and dark chocolate contain relatively
high concentrations of certain polyphenolic compounds,
most notably flavanols. Flavanols, especially the monomer epicatechin and oligomers and polymers offlavanols called proanthocyanins, can act as strong antioxidants in food systems [3]. Notably, cocoa flavanols
have been associated with numerous health benefits
including the stimulation of nitric oxide synthase,
improving blood flow and arterial elasticity, decreasing
blood pressure and platelet aggregation, and having
anti-inflammatory actions [4-6].
Generally, a fruit is thought of as the edible portion ofa plant that surrounds its seeds. The fruit pulp of the
Theobroma cacao pod that surrounds its seeds can beCrozier et al. Chemistry Central Journal 2011, 5:5
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consumed; however the vast majority of people have
only consumed the seed-derived portion of cacao in theform of cocoa powder or chocolate. For this reason, inthe current study we compared cocoa powder and chocolate, products representing the commonly eaten portion of the cacao fruit, with powders and juices fromso-called “Super Fruits” on measures of antioxidant
activity, as measured by oxygen radical absorbance capacity (ORAC), total polyphenol content (TP), and total
flavanol content (TF).

Results and Discussion
Analysis of the fruit powders demonstrated that the
antioxidant capacity (Figure 1A) of cocoa powder (634 ±33 μMTE/g) was significantly greater than blueberry,
cranberry, and pomegranate powder on a per grambasis. The total polyphenol content (Figure 1B) of cocoa
powder (48.2 ± 2.1 mg/g) appeared to be greater thanacai, blueberry, and cranberry powder; however thesedifferences did not reach statistical significance. The
total flavanol content (Figure 1C) of cocoa powder (30.1± 2.8 mg/g) was significantly greater than all of theother fruit powders tested. There were no other statistically significant differences in antioxidant capacity, total
polyphenol, or total flavanol content between any of theother fruit powders tested.
Analysis of fruit products demonstrated that the antioxidant capacity (Figure 2A) of dark chocolate (9911 ±
1079 μMTE/serving) was not significantly greater, on a
per serving basis, than pomegranate juice but was
greater than that of all other products tested. In contrast, hot cocoa mix had significantly less antioxidant
capacity (1232 ± 159 μMTE/serving) than all of theother products tested. The total polyphenol content(Figure 2B) of dark chocolate (991.1 mg/serving) was
significantly greater than all of the other products tested,
aside from pomegranate juice, on a per serving basis.
The total polyphenol content of pomegranate juice wassignificantly greater than that of cranberry juice; all products tested had higher TP values than hot cocoa mix(57.6 ± 4.9 mg/serving). Finally, the total flavanol content (Figure 2C) of dark chocolate (535.6 ± mg/serving)
was significantly greater than cocoa beverage (400 ±39.5 mg/serving) on a per serving basis and both dark
chocolate and cocoa beverage had significantly greater
total flavanol content than hot cocoa mix, acai, blueberry, cranberry, and pomegranate juice.
To limit sampling error with each analysis method,each brand of fruit powder and product was prepared
and analyzed in triplicate. There was excellent agreement in ORAC, TP, and TF values within replicates ofall brands tested. The largest coefficient of variation in
ORAC was 0.095 (data not shown) for replicated tests

Page 2 of 6

of cocoa powder. The largest coefficient of variation in
TP content was 0.085 (data not shown) for replicatedtests of blueberry powder. The largest coefficient of variation in TF content was 0.088 (data not shown) for
replicated tests of pomegranate powder. In contrast to
the lack of methodological variability, there were significant differences in ORAC, TP, and TF values between
brands of some fruit powders and, in particular, fruit
products. As an example, statistically significant differences in ORAC, TP, and TF between brands of acai
juice are demonstrated in Figure 3A, B and 3C.
The results of the current study demonstrate thatcocoa powder has equivalent or significantly higher invitro antioxidant activity, as measured by ORAC values,
compared to the tested fruit powders. Similarly, the TP
content of cocoa powder was equivalent to that of the
fruit powders and its TF content was significantly higher
than that of all the fruit powders tested. In addition, on
a per serving basis, dark chocolate had a significantly
higher ORAC value and TP content than all of the fruit
juices other than pomegranate juice. The ORAC value
and TP content reported for dark chocolate in the current study are consistent with previously publishedresults [7]. These results are also in keeping with a priorstudy which demonstrated greater ORAC values and TP
content in pomegranate juice compared to the otherfruit juices examined in the current study [8]. Moreover,dark chocolate and water-based beverages made withnatural cocoa had greater TF content than the tested
fruit juices. In contrast, hot cocoa mix had significantly
lower ORAC and TP values than all of the fruit juices.
It is important to note that the cocoa powders, cocoa
beverages, and dark chocolates used in this study allcontained natural (or non-alkalized) cocoa. In contrast,
the hot cocoa mixes were made with alkalized or socalled dutched, cocoa. Alkalinization is used to mellow
the flavor of cocoa [9], however the process has beenshown to destroy polyphenolic compounds [10] and islikely responsible for the significant differences in
ORAC, TP, and TC values observed between hot cocoa
mix and the other cocoa products. The extent of polyphenol destruction is proportional to the degree of alkalization and change in the water extractable pH of theresulting powder [10]. Therefore, consumers should beaware that antioxidant capacity and polyphenol content
may be severely diminished in alkalized cocoa powder
and products made with alkalized cocoa.
While all of the fruit powders and fruit juices analyzed
in this study have been previously referred to as Super
Fruits in the popular media, the results of this study
clearly demonstrate that not all brands of powders or
juices from any particular fruit have the same antioxidant capacity or chemical composition. Current FDA

Crozier et al. Chemistry Central Journal 2011, 5:5
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APage 3 of 6800

Antioxidant Activity (uMTE/g)

b
600

ab

400

a

a

a

Blue

Cran

Pom

200

0
Acai

B

Cocoa

Total Polyphenols (mg/g)

80

60

a

a

40

a

a

a

20

0
Acai

Blue

Cran

Pom

Cocoa

C
40

Total Flavanols (mg/g)

b
30

20

10

a

a
a

a

0
Acai

Blue

Cran

Pom

Cocoa

Figure 1 Antioxidant capacity and polyphenol and flavanol content of various fruit powders. A. ORAC antioxidant capacity per gram ofvarious fruit powders. Acai, acai powder; Blue, blueberry powder; Cran, cranberry powder; Pom, pomegranate powder; Cocoa, cocoa powder.
Data are expressed as the mean ± SEM. Columns not sharing superscripts are significantly different, p > 0.05. B. Total polyphenol content
measured in gallic acid equivalents per gram of various fruit powders. Acai, acai powder; Blue, blueberry powder; Cran, cranberry powder; Pom,
pomegranate powder; Cocoa, cocoa powder. Data are expressed as the mean ± SEM. Columns not sharing superscripts are significantly different,p > 0.05. C. Total flavanol content per gram of various fruit powders by the DMAC method. Acai, acai powder; Blue, blueberry powder; Cran,
cranberry powder; Pom, pomegranate powder; Cocoa, cocoa powder. Data are expressed as the mean ± SEM. Columns not sharing superscripts
are significantly different, p > 0.05.

Crozier et al. Chemistry Central Journal 2011, 5:5
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Page 4 of 6

A

Antioxidant Activity (uMTE/serving)

12000

c

10000

b

8000

b

b

b
b

6000
4000

a

2000
0
Acai

B

Blue

Cran

Pom

Cocoa

HCM

d

1200

Total Polyphenols (mg/serving)

Choc

1000

cd
800

bc

bc
600

bc

b

400
200

a

0
Acai

Blue

Cran

Pom

Cocoa

Choc

HCM

C

Total Flavanols (mg/serving)

800

c

600

b
400

200

a

a

a
a

a

0

Acai

Blue

Cran

Pom

Cocoa

Choc

HCM

Figure 2 Antioxidant capacity and polyphenol and flavanol content of various fruit products. A. ORAC antioxidant capacity per serving ofvarious fruit products. Acai, acai powder; Blue, blueberry powder; Cran, cranberry powder; Pom, pomegranate powder; Cocoa, cocoa beverage;
Choc, dark chocolate; HCM, hot cocoa mix. Data are expressed as the mean ± SEM. Columns not sharing superscripts are significantly different,p > 0.05. B. Total polyphenol content measured in gallic acid equivalents per serving of various fruit products. Acai, acai powder; Blue, blueberry
powder; Cran, cranberry powder; Pom, pomegranate powder; Cocoa, cocoa beverage; Choc, dark chocolate; HCM, hot cocoa mix. Data areexpressed as the mean ± SEM. Columns not sharing superscripts are significantly different, p > 0.05. C. Total flavanol content per serving ofvarious fruit products by the DMAC method. Acai, acai powder; Blue, blueberry powder; Cran, cranberry powder; Pom, pomegranate powder;
Cocoa, cocoa beverage; Choc, dark chocolate; HCM, hot cocoa mix. Data are expressed as the mean ± SEM. Columns not sharing superscripts
are significantly different, p > 0.05.

Crozier et al. Chemistry Central Journal 2011, 5:5
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APage 5 of 6

40cAntioxidant Activity (uMTE/g)

35
30

b

25
20
15

a

10
5
0
Brand 1

B

Brand 2

Brand 34cTotal Polyphenols (mg/g)

3.5
3
2.5
2

b
a

1.5
1
0.5

Methods0

Sample Collection and Preparation
Brand 1C

Brand 2

1.2

Brand 3cTotal Flavanols (mg/g)

1
0.8
0.6
0.4

Conclusions
In summary, natural cocoa powder and dark chocolate
have significantly greater TF values than the other fruit
powders and juices tested, respectively. The high concentration of flavanols, as well as other flavonoid compounds not tested in this study, contributes directly tothe observed TP and ORAC values of natural cocoa anddark chocolate. Cocoa powder thus provides nutritive
value beyond that derived from its macronutrient composition. Based on this criterion, and borrowing terminology from popular media, cacao seeds should beconsidered a “Super Fruit” and products derived from
cacao seed extracts, such as natural cocoa powder anddark chocolate, as “Super Foods”. In contrast, products
made with alkalized cocoa have relatively low ORAC,
TP and TF values. It is important to note that ORAC,
TP and TF values varied significantly between somebrands of fruit powders and fruit juices. Therefore, consumers should be aware that brands of cocoa and fruit
powders and products may differ substantially in theirnutritive value.

b

0.2

a

0
Brand 1

Brand 2

Brand 3Figure 3 Differences in antioxidant capacity and polyphenol
and flavanol content between brands of acai juice. A. ORAC
antioxidant capacity per gram of individual acai juice brands. Data
are expressed as the mean ± SEM. Columns not sharing superscripts
are significantly different, p > 0.05. B. Total polyphenol content
measured in gallic acid equivalents per gram of individual acai juice
brands. Data are expressed as the mean ± SEM. Columns not
sharing superscripts are significantly different, p > 0.05. C. Total
flavanol content per gram of individual acai juice brands by the
DMAC method. Data are expressed as the mean ± SEM. Columns
not sharing superscripts are significantly different, p > 0.05.

regulations do not require that antioxidant capacity and/or polyphenol content be provided on food labels. Inclusion of this information, as has been suggested previously [10], could assist consumers in differentiating
between brands and in making healthier food choices.

Materials selected for this study included commerciallyavailable fruit powders [acai, blueberry, cranberry, pomegranate], natural (non-alkalized) cocoa, 100% non
blended fruit juices [acai, blueberry, cranberry, pomegranate], natural cocoa beverage, solid dark chocolate(60-63% cacao), and hot cocoa mix. All powders wereobtained via food ingredient vendors. All juices, solid
dark chocolate, and hot cocoa mix were obtained at retailand analyzed in the form sold to consumers, ie. hotcocoa mixes were not combined with milk or water prior
to analysis. Cocoa beverage was produced by combining
240 ml water, 25 g sugar, 1 g salt, and 12 g of natural
cocoa powder and was designed to have a composition
similar to that of the other fruit juices. One cup (240 ml)
was considered a typical single serving of fruit juice or
cocoa beverage, 40 g was considered a typical single serving of dark chocolate, and 28 g was considered a typicalsingle serving of hot cocoa mix. Three brands wereselected per fruit powder and fruit product. Each brand
was analyzed for ORAC, TP, and TF in triplicate.
Antioxidant Capacity Analysis

Sample ORAC values were quantified by measuring thefluorescence of fluorescein in the presence of 2,2’-azobis(2-amidinopropane) dihydrochloride (AAPH) [11,12].
Quantitation was based on a trolox (6-hydroxy,2,5,7,8tetramethylchroman-2-carboxylic acid) standard calibration curve, and results are reported as μm trolox
equivalents per gram of sample for fruit powders andμm trolox equivalents per serving for fruit products.

Crozier et al. Chemistry Central Journal 2011, 5:5
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Total Polyphenol Assay

Sample total polyphenol content was determined colorimetrically at 755 nm using Folin-Ciocalteu reagent as
described by Singleton et al. [13]. Quantitation was
based on a gallic acid standard calibration curve. Total
polyphenols are reported as gallic acid equivalents pergram of sample for fruit powders and gallic acid equivalents per serving for fruit products.

Page 6 of 6

5.
6.

7.

8.

Total Flavanol Assay

Sample total flavanol content was determined colorimetrically at 640 nm using 4-dimethylaminocinnamaldehyde (DMAC) as described by Payne et al. [14].
Quantitation was based on a procyanidin B-2 standard
calibration curve, and results are reported as mg/g oftotal flavanols per gram of sample for fruit powders andmg per serving for fruit products.
Statistical Analysis

Fruit powders and products were compared using a oneway ANOVA with brand or type of fruit powder or product as the independent variable and ORAC, TP, and
TF as dependent variables. The least square mean foreach type of fruit powder or product was calculated
from the mean value of the three brands used. Differences between brands or types of fruit powders or products were identified by a post hoc analysis conductedusing Fisher’s LSD. Analyses were conducted using The
Statgraphics Centurion software purchased from Manugistics, Inc., Rockville, MD, 20852, USA.

9.
10.

11.

12.

13.

14.

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doi:10.1186/1752-153X-5-5
Cite this article as: Crozier et al.: Cacao seeds are a “Super Fruit": A
comparative analysis of various fruit powders and products. Chemistry
Central Journal 2011 5:5.

Acknowledgements and funding
The authors would like to express sincere appreciation to Austin Snyder andAllison Dilzer for technical assistance and Dr. David Stuart for suggestions
and critical reading of the manuscript. This work was funded by The
Hershey Company (Hershey, PA).
Authors’ contributions
AGP, JM, and DLM conceived and designed the study. WJH and MJP carriedout the chemical assays. SJC performed the data analysis and drafted themanuscript. LH performed the statistical analysis. All authors read andapproved the final manuscript.
Competing interests
SJC is a paid contractor for The Hershey Company. AGP, WJH, MJP, JM, LH,
and DLM are employees of The Hershey Company.
Received: 2 November 2010 Accepted: 7 February 2011
Published: 7 February 2011
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2. Cuatrecasas J: Cacao and its allies: a taxonomic revision of the genus
Theobroma. Contributions from the United States National Herbarium 1964,
35:379-614.
3. Beckett ST: Industrial chocolate manufacture and use Glasgow: Blackie; 1988.
4. Corti R, Flammer AJ, Hollenberg NK, Luscher TF: Cocoa and Cardiovascular
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