Abstract
Effect of Replacing Raisins with Goji Berries and Cacao Nibs on
Sensory Perception of Flavor Texture and Aftertaste of Oat Bar
Objective: People are looking for quick meals that are easy to eat
on the run, and often turn to pre-made breakfast or snack bars to
fulfill this need. Additionally, consumers are demanding products
that are more healthful and reasonably priced. This experiment set
forth to identify if changing a standard recipe from containing
raisins to cacao nibs and goji berries would enhance the palatability
of texture, flavor and aftertaste.
Methods: One standard recipe was used and both bars were made
at the same time using the same ingredients with the acceptation
of adding raisins to the control bar, and cacao nibs and goji berries
to the experiment bar. The following morning participants were
accrued in the hallway at Bastyr University and 26 total participants
tasted both bars and completed a sensory analysis.
Results: Results were calculated using a related-samples t-test.
The mean flavor of Bar A (5.846) was significantly less than the
mean flavor of Bar B (6.385), the mean texture of Bar A (5.885) was
significantly less than the mean texture of Bar B (6.462), and the
mean aftertaste of Bar A (6.385) was significantly greater than the
mean aftertaste of Bar B (5.808). The mean difference in scores
between Bar A and Bar B was over half a score point (0.538) for
flavor and (5.77) for texture and aftertaste.
Conclusion:
Adding goji berries and cacao nibs increased
preference for flavor and texture but caused an undesirable
aftertaste.
Introduction
More and more people are eating on the go or looking for quick
portable snack options. Protein or granola bars are popular choices
whether looking for a snack or a quick breakfast while running out
the door. Healthier versions of these types of foods are sometimes
thought to lack flavor or to be unappealing overall. The purpose of
this experiment was to create a food bar with better flavor, texture
and overall acceptability while providing added health benefits. It
was thought that by taking out raisins and adding goji berries and
cacao nibs, the food bar would have both an improved nutritional
and taste profile. Areas measured were texture, flavor, and
aftertaste.
Cacao nibs are coca beans that have been roasted, separated from
their husk and broken into smaller pieces. When incorporated into
baked goods they provide an added crunch and chocolaty flavor.
Nutritionally speaking, 1oz of cacao nibs contains 130 calories, 13g
of fat, 10g of carbohydrates, and 3g of protein. They are a good
source of magnesium with 77mg in 1oz (1). In a study that
employed emulsion preparations to test the mineral content of
chocolate it was found that dark chocolate has a substantial
concentration of both magnesium and potassium. Minor
component contents include iron and zinc (2). Recent research has
been undertaken to determine the antioxidant capacity of cocoa
and its potential benefits to humans. There is some indication that
proposed health benefits of consuming chocolate can be attributed
to its rich polyphenol content. Cacao polyphenols have been
suggested to positively influence cardiovascular health through
inhibition of lipid peroxidation, platelet activation or cyclooxegenase, and lipoxygenase activities, and enhancing levels of the
endothelial derived relaxing factor nitric oxide (4).
Lycium barbarum, more commonly known as goji or wolfberry has
been used since ancient times in traditional Chinese medicine to
nourish the liver and kidney and brighten the eye. Recent studies
indicate that extracts from L. barbarum fruit and one of its active
compounds, polysaccharides (LBP) possess various biological
activities that include effects on aging, neuroprotection, antifatigue/endurance, increased metabolism, glucose control in
diabetics, glaucoma, antioxidant properties, immunomodulation,
anti-tumor activity, and cytoprotection (5).
April Ayers, Erica Gaddis, Adrienne Holloway
Bastyr University, Kenmore, WA
Hypothesis and Purpose
Hypothesis: Removing raisins and adding goji berries and cacao
nibs, two functional foods, will change the desirability of the food
bar as a more healthful product.
Independent Variables: raisins (control), cacao nibs and goji berries
(experiment)
Dependent Variables: texture, flavor, and aftertaste as rated on a
9-point scale
Sensory Analysis Participants were asked to rank their opinion of
the texture, flavor and aftertaste of each bar on a scale of 1 to 9.
The control and experiment bar looked the same after being
cooked and cut, therefore the sensory test focused on sensory
characteristics other than appearance These three sensory
characteristics are instrumental to a consumers’ decision to
purchase the bar on a regular basis.
The purpose of this experiment was to create a food bar with
better flavor, texture and overall acceptability while providing
added health benefits. Cacao nibs should add a nice crunchy
texture and chocolaty flavor. There is however, the potential for
some to find the cacao too bitter. Goji berries might be a tasty
alternative to raisins while providing a number of macro and
micronutrients and potential antioxidant benefits.
Cacao, or Theobroma Cacao has been recognized for centuries for
its medicinal properties and is considered a functional food because
it contains substances that are considered beneficial to health. A
few of these substances include flavonoids, flavanols, and
polyphenols.
Goji berries, or wolfberries have been used in medicine and as a
functional food in Asia for at least 2,000 years. Due to their
increasing acceptance as “superfood” in the Western world it has
become widely utilized in a variety of food products. There are
several reported benefits associated with goji berries, which
include their ability to improve vision, kidney and liver function,
increase immunity and delay the signs of aging. (11).
Aftertaste was the only sensory factor in which participants
preferred the control Bar A to experimental Bar B. The flavanol
compounds contained in the raw cacao produce a distinctive bitter
taste. Favorability for this taste will vary amongst individuals and
can be considered a piece for further investigation to reduce
aftertaste (12).
Materials and Methods
Participants
Participants were students passing through the main floor hallway
near the dining commons at Bastyr University in Kenmore, WA, on
a Monday morning between 10:00am and 11:45am. Participants
were asked if they would like to participate in a short taste-test
with a survey as they passed by the test table. Twenty-six students
completed the taste test and survey.
Two factors that may have influenced the results were
psychological bias and gluten free ingredients. The first bias that
may have occurred when participants learned that the second bar
contained cacao nibs and goji berries which may have compelled
them to give higher sensory scores to Bar B thus affecting the
overall mean scores for these categories.
Ingredient Intervention
Bar A (control recipe) contained raisins, where as Bar B (experiment
recipe) contained goji berries and cacao nibs in place of the raisins.
Study Design
Both bars were made at the same time, using the same ingredients
with the following exceptions: the control, Bar A, contained 1/2
cup regular raisins; the experiment, Bar B, contained 1/2 cup goji
berries and 1/3 cup cacao nibs, shown in Table 1. All ingredients
were certified or guaranteed to be free of gluten ingredients and
processed on clean or dedicated gluten-free equipment.
Conclusion
The research showed that participants had an increased preference
for the experimental Bar B in both flavor and texture, while the
control bar Bar A, was more desirable in terms of aftertaste. The
addition of both cacao nibs and goji berries, not only provides
favorable characteristics in flavor and texture, but also provides a
host of healthful benefits.
Results
A total of 26 Bastyr University students, all over the age of 18,
completed the study by tasting both bars and filing out the survey
in full. The mean flavor of Bar A (5.846) was significantly less than
the mean flavor of Bar B (6.385), which shows that there was a
greater preference for the flavor of Bar B. The mean texture of Bar
A (5.885) was significantly less than the mean texture of Bar B
(6.462), which shows that there was a greater preference for the
texture of Bar B. The mean aftertaste of Bar A (6.385) was
significantly greater than the mean aftertaste of Bar B (5.808)
which shows that there was a greater preference for the aftertaste
of Bar A. The mean difference in scores between Bar A and Bar B
was over half a score point (0.538) for flavor and (5.77) for texture
and aftertaste.
Table 2 Sensory Scorecard with three independent variables (texture, flavor,
aftertaste) judged on a preference rating scale of 1 to 9.
The other factor that may have influenced the outcome was that all
the ingredients utilized in the creation of the bars were either
certified gluten free or manufactured on gluten-free
equipment. Making the bars gluten-free would enhance the
product marketability to the health conscious and gluten free
market, but might have an increased cost associated with
manufacturing.
The experiment concluded that aftertaste was not a favorable
component for participants. Further investigation into ingredient
finished flavor profile could improve this. The cacao nibs in
particular demonstrated a strong recognizable flavor, but also
provided optimal health benefits as a functional food. In order to
maintain the health benefits a sweetener such as honey could be
incorporated to calm the sharp taste or, almond butter could be
added to create richness so that the cacao would be a
complementary flavor in the bar.
Resources