INTRODUCTION
Phoenix dactylifera L. is commonly known as
Nakhel Al-Tamr in Arabian countries and as the date
palm in English. A member of the genus Phoenix in the
Arecaceae family, it grows in the hot desert regions of
North Africa. In Egypt, dates have been an economically
important food crop for thousands of years. According
to the earliest records of predynastic Egypt (excavation
of a vat in Hierakonpolis, Upper Egypt, 3450 BC),
they were used as a beer sweetener. However, their
cultivation started somewhat later than in Iraq (about
3000–2000 BC) [1, 2].
Egypt is at the top of the world’s date-producing
countries. In 2019, its production totaled 1.61 million
tons, representing 16.41% of the world’s production of
9.75 million tons [3]. Date fruits are a cheap and rich
source of carbohydrates (70–80%) in the form of glucose
and fructose, proteins, amino acids, and essential
minerals (zinc, copper, selenium, potassium, calcium,
magnesium, phosphorus, manganese, and iron), fiber,
vitamins C and E, carotenoids, fatty acids, polyphenols,
and flavonoids. Known as “emerging healthy foods” due
to their health benefits, dates are commonly processed
into juice, syrup, and paste, with many applications in
other foods such as confectionary, bakery, and dairy
products [2, 4–6]. As a result of agri-food production,
large amounts of organic waste are produced as press
cake that is mainly used as animal fodder and also in
biofuel production [7].
Date press cake is a fibrous material that remains
after date juice filtration. This by-product is a cause
of disposal problems and environmental issues due
to its bulky nature, high moisture, and carbohydrate
content [2]. Date juicing accounts for 17–28% of date
press cake that is dumped into open lands and drains or
used as stock feed. However, it has been underutilized
in the food industry, mainly due to the lack of technical
knowledge about its nutritional value, health benefits,
and possible effects on the quality of food products [2,
8]. In this context, we aimed to produce vegan biscuits
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and vegan protein bars from date press cake and assess
their quality and nutritional value.
STUDY OBJECTS AND METHODS
The objects of the study were vegan protein bars
(commercial and experimental that contained date press
cake powder) and vegan biscuits (control sample and
samples with 5, 10 and 15% of date press cake powder).
Materials. Date press cake was obtained from Al
Tahhan Golden Dates Factory (New Valley Governorate,
Egypt). Crisp rice (rice flour-corn flour-wheat flour
72%-calcium carbonate) was a gift from Caker Food
Industries (New Damietta City, Egypt). Other dry
ingredients and corn oil for our innovative vegan protein
bars and vegan biscuits were purchased from the Metro
Market (Egypt). The control was a commercial protein
bar (Go Food Bar) (dates, almonds, cashew, cocoa)
purchased from the Advanced Sport Nutrition Company
(Cairo, Egypt). All the chemicals and equipment used in
this research were of analytical grade.
Technological methods. Processing methods.
Production of date press cake powder. After juicing
fully matured Saidi dates, press cake was ground in
a laboratory grinder, sieved through a 70 mesh sieve
to obtain particles of 210 microns, and stored in sealed
polyethylene bags at –18°C for technology application,
as described in [6].
Preparation of vegan protein bars. Our innovative
vegan protein bars were prepared in the following stages:
– good quality dried peeled split fava beans were rinsed,
soaked in water for 12–13 h, boiled in plenty of water for
4 min until tender but not mushy; then drained, tossed
in the oil, and spread out in a single layer on a baking
sheet, and roasted at 185°C until golden and crispy;
– yellow split chickpeas and roasted split fava
beans were individually milled in a laboratory mill
(JKA-Labora technic, Janke and Kunkel Type: MFC,
Germany);
– oat was roasted in an aluminum pan at 140°C in a low
flame to get roasted aroma;
– 10 g of date press cake powder was mixed with 40 g of
other dried ingredients (yellow split chickpeas, roasted
split fava beans, instant coffee, oat, salt, coconut powder,
crisp rice);
– glucose syrup (26 g) and molasses (24 g) were
heated to 70°C for 2.5 min, mixed well with all dried
ingredients and 2 mL of oil, molded into a bar shape
(8×2.3×1.5 cm), and finally packaged in airtight
polyethylene bags (HDPE) before measurements;
– the samples were stored at room temperature 25 ± 5°C
for 8 months for microbiological assays.
Preparation of vegan biscuits. Control biscuit dough
was prepared using 100 g wheat flour (72% extraction),
25 g powdered sugar, 22 g corn oil, 1 g sodium chloride,
1 g ammonium bicarbonate, and 28 g water, as described
in [9]. Experimental samples contained 5, 10 or 15% of
date press cake powder instead. Biscuits were prepared
in the following stages:
– sugar was mixed with corn oil and creamed intensively
(speed 5) for 3 min in a KitchenAid mixer;
– wheat flour (72% extraction), sodium chloride,
ammonium bicarbonate, and water were added to
prepare dough;
– the dough was manually mixed for 15 min into a
uniform smooth paste [10];
– biscuits were formed and baked in an oven at 180°C
for about 25 min;
– the biscuits were cooled at room temperature 25 ± 5°C,
packaged in airtight polyethylene bags before measurements,
and stored at room temperature for 8 months for
microbiological assays.
Palatability test. Palatability evaluation of our
products was carried out by ten experienced panelists
from the Food Technology Research Institute
(Agricultural Research Center, Giza, Egypt) according
to the method described in [11]. Then, 30 consumers
from the local market who were willing to buy the
products were also tested according to [12].
Evaluation of the nutritional value. The samples
were analyzed for moisture, ash, protein, crude fiber,
and crude fat on a dry weight basis according to the
standard procedures recommended by [13]. %Available
carbohydrates (on dry basis) = 100 – (%Ash + %Fat +
%Protein + %Fiber), as mentioned by [15]. Energy
(Kcal) was calculated by the formula of [14] as follows:
Energy (Kcal) = [Protein (g)×4] + [Carbohydrate
(g)×4] + [Fat (g)×9]. Minerals, i.e., calcium (Ca),
iron (Fe), Magnesium (Mg), Potassium (K), Manganese
(Mn), and Zinc (Zn) were determined using an Atomic
Absorption Spectrophotometer (3300 Perkin-Elme), as
described in [13].
Texture profile analysis. Texture properties of our
products, such as chewiness, gumminess, springiness,
cohesiveness, and hardness, were estimated using a
CT3 Texture Analyzer (Version 2.1, 10 000 Gram unit,
Brookfield, Engineering Laboratories, Inc., USA),
according to the method of [16].
Scanning electron microscopy. Scanning electron
microscopy (SEM) was used to visualize the
microstructure of the bars, as described by [17].
Microbiological analysis. Total bacterial, yeast, and
mold counts were carried out during different storage
periods according to [18].
Statistical analysis. The statistical analysis was
performed using SPSS One-Way ANOVA, version
22 (IBM Corp.) released in 2013. Data were treated as
a complete randomization design according to [19].
Multiple comparisons were carried out applying the
Duncan test. The significance level was P < 0.05.
RESULTS AND DISCUSSION
Chemical composition and minerals content. The
chemical composition and mineral content of Saidi date
press cake are shown in Table 1. As we can see, Saidi
date press cake contained 6.11% moisture, 5.12% fat,
7.4% protein, 12.38% crude fiber, 2.78% ash, and 66.21%
carbohydrates. Of the six minerals determined in the
sample, Mg had the highest content, while Mn had the
lowest content. These findings are in agreement with
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those reported by [2], who found that Shahani date press
cake contained an average of 4.92% fat and 11.74% crude
fiber, while Na, K, Cu, Zn, and Fe amounted to 2.05,
29.93, 9.06, 19.72, and 80.75 mg/kg–1, respectively.
Palatability tests. Vegan protein bars. Sensory
evaluation is an important indicator of potential
consumer palatability. Table 2 presents the sensory
scores for the tested vegan protein bars, commercial
and innovative. As we can see, the innovative protein
bar obtained a significantly higher sensory score in
flavor, taste, texture, and overall acceptability, while the
commercial protein bar scored higher in color, which
might be due to chocolate. However, the willingness to
buy the vegan protein bars was significantly higher for
the innovative samples (27.3 ± 0.58) than the commercial
samples (25.00 ± 01.0), with 91 and 83.33% of the
respondents, respectively.
Vegan biscuits. A preference experiment was
designed to select the best ratio of raw materials for
vegan biscuits. According to the palatability results
(Table 3), the control biscuit and fortified biscuits with 5
and 10% date press cake powder (DPC) scored higher in
color, flavor, taste, texture, and overall acceptability. The
sample with 10% DPC and 90% wheat flour received
Table 1 Chemical composition (dry weight)
and mineral content of Saidi date press cake powder
Parameters Content
Moisture, % 6.11
Protein, % 7.4
Crude fiber, % 12.38
Fat, % 5.12
Ash, % 2.78
Total carbohydrates, % 66.21
Minerals, mg/kg–1:
Mn 10.9
Ca 502
Fe 78.45
Zn 19.2
M 625
K 27.4
Table 2 Sensory evaluation and willingness to buy vegan
protein bars with data press cake powder
Parameters Samples
Commercial bar Innovative bar
Color 9.80 ± 0.95 7.14 ± 0.72b
Flavor 6.95 ± 0.30b 8.35 ± 0.23a
Taste 7.73 ± 0.21b 9.30 ± 0.20a
Texture 7.83 ± 0.16b 8.40 ± 0.20a
Overall acceptability 8.18 ± 0.45b 9.13 ± 0.20a
Willingness to buy the
vegan protein bar samples:
Yes 25.00 ± 01.00b 27.3 ± 0.58a
No 5.0 ± 1.0a 2.66 ± 0.57b
a–b: If there is no significant difference (P > 0.05) between any two
means, they have the same superscript letter within the same column.
Table 3 Sensory preference test and willingness to buy biscuit with 10% of date press cake powder
Parameters Samples
Control 5% DPC 10% DPC 15% DPC
Color 6.30 ± 0.71b 8.06 ± 0.07a 9.02 ± 0.15a 5.40 ± 0.23b
Flavor 7.18 ± 0.28b 8.20 ± 0.23a 8.68 ± 0.14a 5.21 ± 0.26c
Taste 7.54 ± 0.06c 8.08 ± 0.08b 9.07 ± 0.12a 4.67 ± 0.18d
Texture 7.96 ± 0.89a 8.51 ± 0.10a 8.17 ± 0.11a 4.07 ± 0.22b
Overall acceptability 7.73 ± 0.17c 8.16 ± 0.18b 8.86 ± 0.05a 4.17 ± 0.15d
Willingness to buy the vegan biscuit samples
Samples Control 5% DPC 10% DPC 15% DPC
Yes 20.20 ± 0.59c 23.20 ± 0.51b 27.00 ± 0.33a 13.90 ± 0.86d
No 9.80 ± 0.59b 6.80 ± 0.51c 3.00 ± 0.33d 16.10 ± 0.86a
a–d: If there is no significant difference (P > 0.05) between any two means, they have the same superscript letter within the same column.
DPC – date press cake.
the most significant scores in color, taste, and overall
palatability. Additionally, most of the respondents (90%)
were significantly willing to buy this sample, compared
to the other samples. Since the 10% sample showed the
best preference, we selected it for our further studies.
Nutritive values of investigated products. Vegan
protein bars. The nutritive values of commercial and
innovative vegan protein bars are shown in Table 4.
We found that the innovative bar scored significantly
higher in protein, fiber, energy, and minerals, compared
to the commercial bar. However, fat and moisture were
significantly lower. Snack bars with high energy are
consumed by top athletes to improve their performance.
Therefore, the commercial and innovative bars could be
introduced in their diet, as described by [20].
The recommended dietary allowances (RDA) given
by the Indian Council of Medical Research (ICMR) for
female and male athletes, respectively, are as follows:
energy 3600 and 4500 Kcal/day, protein 82.5 and
120 g/d, fat 30 and 40 g/d, carbohydrates 585 and
731.25 g/d, iron 21 and 17 mg/d, and calcium 600 mg/d
for females and males, as reported by [21, 22]. Our
results indicated that 100 g of the innovative bar
provided the following percentages of the RDAs for
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female and male athletes, respectively: energy 12.60 and
10.08%, protein 23.42 and 16.1%, fat 20.8 and 15.6%,
carbohydrates 13.38 and 10.71%, iron 11.90 and 14.70%,
and calcium 3.23% for both. The results for 100 g
of the commercial bar were as follows: energy 11.90 and
9.52%, protein 14.9 and 10.25%, fat 27.5 and 20.7%, iron
6.95 and 8.59%, and calcium 1.74% for both females
and males. The intake of total calories, carbohydrates,
proteins and fats were normal in female athletes but less
than RDAs [23].
Adolescence is а transition period between childhood
and adulthood from 13 to 17 years of age. Therefore,
adolescents need additional calories, protein, calcium,
and iron [24]. According to [25], the recommended
intake for female and male adolescents, respectively,
is as follows: energy 2200 and 2900 Kcal/d, protein 46
and 58 g/d, iron 15 and 10 mg/d, calcium 1200 mg/d
for both sexes, and zinc 12 and 15 mg/d. We found that
100 g of the innovative bar covered the recommended
intake at the following levels in females and males,
respectively: energy 20.62 and 15.64%, protein 42.0 and
33.3%, iron 16.67 and 25.00%, calcium 1.61% for both
sexes, and zinc 17.5 and 14.0%. The results for 100 g of
the commercial bar were as follows: energy 19.25 and
14.77%, protein 26.73 and 21.20%, iron 9.7 and 14.6%,
calcium 0.87% for both sexes, and zinc 10.33 and 8.66%.
Vegan biscuits. The nutritive values for the vegan
biscuit fortified with 10% DPC and the control vegan
biscuit are given in Table 5. The 10% DPC sample
contained higher moisture, protein, fiber, energy, iron,
zinc, calcium, potassium, magnesium, and manganese
but lower ash, fat, and carbohydrates. In addition, 100 g
of the 10% biscuit met the daily requirement in female
and male adolescents, respectively, for energy 20.47
and 15.53%, protein 18.91 and 15.00%, iron 19.33 and
29.00%, calcium 1.87% for both sexes, and zinc 10.08
and 8.06%. The results for 100 g of the control biscuit
were as follows: energy 16.08 and 12.75%, protein 19.54
and 14.83%, iron 12.4 and 18.6%, calcium 1.35% for
both sexes, and zinc 4.25 and 3.40%, as reported by [25].
We found that a 100 g serving of the 10% DPC
biscuit provided a substantial proportion of the RDAs
established by the ICMR for female and male athletes,
respectively, in relation to energy 12.10 and 9.68%,
carbohydrates 13.23 and 10.58%, fat 31.63 and 7.25%,
protein 10.55 and 7.25%, iron 13.80 and 23.73%, and
calcium 3.75% for both sexes. The control biscuit (100 g)
showed the following values: energy 11.90 and 9.55%,
carbohydrates 13.45 and 10.76%, protein 9.4 and 6.1%,
fat 39.06 and 29.30%, iron 8.85 and 10.94%, and calcium
2.7% for both sexes, according to [22].
Texture profile analysis and scanning electron
microscopy. Vegan protein bars. Texture profile analysis
Table 4 Nutritive values of innovative protein
bar vs. commercial protein bar
Parameters Vegan protein bars
Commercial bar Innovative bar
Moisture, % 13.46 ± 0.17a 6.89 ± 0.38b
Protein, % 12.30 ± 0.17b 19.32 ± 1.24a
Fat, % 8.26 ± 0.24a 6.25 ± 0.21b
Fiber, % 0.67 ± 0.06b 2.10 ± 0.07a
Ash, % 1.21 ± 0.05b 1.80 ± 0.07a
Carbohydrate, % 79.00 ± 0.20a 78.30 ± 0.43a
Energy, Kcal/100 g 428.59 ± 2.59b 453.73 ± 2.39a
Iron, mg/100 g 1.46 ± 0.08b 2.50 ± 0.15a
Zinc, mg/100 g 1.30 ± 0.08b 2.10 ± 0.11a
Calcium, mg/100 g 36.00 ± 2.40b 45.70 ± 2.21a
Potassium, mg/100 g 199.66 ± 1.20b 214.66 ± 1.76a
Mg, mg/100 g 19.30 ± 0.41b 28.18 ± 0.61a
Mn, mg/100 g 1.34 ± 0.06b 1.83 ± 0.04a
a and b: If there is no significant difference (P > 0.05) between any two
means, they have the same superscript letter within the same column.
Table 5 Nutritive values for vegan biscuits fortified with 10%
of date press cake powder vs. control vegan biscuits
Parameters Vegan biscuits
Control 10% DPC
Moisture, % 3.89 ± 0.11b 4.76 ± 0.09a
Protein, % 7.40 ± 0.18b 8.70 ± 0.11a
Fat, % 11.72 ± 0.19a 9.49 ± 0.24b
Fiber, % 0.90 ± 0.01b 2.53 ± 0.14a
Ash, % 1.83 ± 0.06b 1.16 ± 0.12a
Carbohydrate, % 78.70 ± 0.45a 77.39 ± 0.52a
Energy, Kcal/100 g 430.01 ± 0.54b 450.48 ± 0.63a
Iron, mg/100g 1.86 ± 0.03b 2.90 ± 0.24a
Zinc, mg/100g 0.51 ± 0.11b 1.21 ± 0.02a
Calcium, mg/100g 16.22 ± 0.56b 22.51 ± 1.73a
Potassium, mg/100g 135.66 ± 7.20b 158.66 ± 3.17a
Mg, mg/100g 14.60 ± 0.69b 19.50 ± 0.84a
Mn, mg/100g 0.37 ± 0.03b 1.67 ± 0.22a
a and b: If there is no significant difference (P > 0.05) between any two
means, they have the same superscript letter within the same column.
Table 6 Texture profile of vegan protein bars (mean ± SE)
Samples Texture profile analysis
Chewiness (mJ) Gumminess (N) Springiness Cohesiveness (mm) Hardness (N)
Commercial bar 32.63 ± 0.81a 17.42 ± 0.54a 1.10 ± 0.32a 22.40 ± 1.93b 35.54 ± 1.00b
Innovative bar with data powder 25.97 ± 1.54b 14.33 ± 0.42b 1.96 ± 0.05a 31.73 ± 1.68a 43.58 ± 2.28a
a and b: If there is no significant difference (P > 0.05) between any two means, they have the same superscript letter within the same column.
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Figure 1 Scanning electron microscopy images for
experimental vegan protein bars. IP – innovative protein bar.
CP – commercial protein bar. Magnifications of 1500×
Table 7 Texture profile of vegan biscuits (mean ± SE)
Treatment Physical properties
Chewiness (mJ) Gumminess (N) Springiness (mm) Cohesiveness (mm) Hardness (N)
Control biscuits 65.93 ± 1.74a 28.33 ± 0.88a 3.25 ± 0.07a 0.55 ± 0.06b 35.05 ± 4.04b
Biscuits fortified with 10%
of date cake powder
42.68 ± 1.24b 16.44 ± 1.26b 2.40 ± 0.04b 1.20 ± 0.08a 56.20 ± 3.53a
LSD at 0.05 5.92 4.28 0.21 0.26 14.90
a and b: If there is no significant difference (P > 0.05) between any two means, they have the same superscript letter within the same column.
Figure 2 Scanning electron microscopy images
of experimental vegan biscuits. DB – 10% DPC-fortified
biscuits. CB – Control biscuits. Magnifications of 1500×
is another important measure of a food product’s overall
quality and consumer acceptability. The results of
texture analysis of the vegan protein bars (commercial
and innovative) are shown in Table 6. We found that
the DPC-fortified innovative bar showed significantly
higher (P ≤ 0.05) hardness and cohesiveness values, but
significantly lower gumminess and chewiness values,
compared to the commercial bar, which contained date
and was coated with chocolate. The increased hardness
of our innovative bars may be due to the migration
of moisture between carbohydrates (such as starches,
pectins, sugars, and maltodextrin) and proteins, or
due to their protein content increase (19.32%), as
shown in Table 4 [26]. However, the hardness of highprotein
bars is quite high. It increases with the addition
of protein and is characterized by a large variety
of parameters [27].
The microstructures of cross-sectional areas of the
commercial and innovative protein bars are shown in
Fig. 1. As we can see, the innovative bar had a wavy
structure, with few cavities and air pores, and relatively
high hardness, while the commercial bar had a round
structure with a number of cavities and air pores. A
formation of large protein clusters (agglomerates) was
probably the cause of the increased hardness of the
innovative bar [27]. The formation of characteristic
agglomerates in the innovative bar might be due to the
presence of lectin sources in its ingredients. Lectins
are glycoproteins known for their aggregation and
high specificity binding with carbohydrates without
initiating a modification through associated enzymatic
activity. This leads to the formation of compact and hard
structures, accounting for high hardness, factorability,
and adhesiveness [27, 28].
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Table 8 Total bacterial, yeast and mold count (CFU/g) of 10% DPC vegan biscuit and innovative vegan protein bar during storage
at room temperature 25 ± 5°C
Total bacterial count, CFU/g
Storage period
(month)
Vegan biscuit Innovative vegan protein bar
Control 10% DPC
Number
of cells (CFU/g)
Log
survivor
Number
of cells (CFU/g)
Log
survivor
Number
of cells (CFU/g)
Log
survivor
0 ND – ND – ND –
2 1.6×102 2.20 1.1×102 2.04 ND –
4 3.7×102 2.57 2.2×102 2.34 ND –
6 5.0×102 2.70 3.9×102 2.59 6.0×10 1.78
8 7.0×102 2.85 4.0×102 2.60 9.0×10 1.95
Yeast and mold count, CFU/g
Storage period
(month)
Vegan biscuit Innovative vegan protein bar
Control 10% DPC
Number
of cells (CFU/g)
Log
survivor
Number
of cells (CFU/g)
Log
survivor
Number of cells
(CFU/g)
Log
survivor
0 ND – ND – ND –
2 ND – ND – ND –
4 4.0×10 1.60 ND – ND –
6 6.0×10 1.78 3.0×10 1.48 ND –
8 2.6×102 2.41 1.1×102 2.04 2.0×10 1.30
*ND – Not detected.
Vegan biscuits. Biscuits are a type of bakery
products with minimal mixing and low water activity.
Short dough has minimal, if any, gluten development
that results in the production of smaller biscuits. In our
study, the addition of date press cake caused a significant
increase (P ≤ 0.05) in hardness and cohesiveness, as well
as a significant decrease in springiness, gumminess, and
chewiness, compared to the control sample. This was
due to the effect of fibers that have high water and oil
adsorption capacity [29].
Majzoobi et al. indicated that date press cake can
promote starch retrogradation and protein aggregation,
which can also account for the increased hardness and
reduced springiness [6]. So, the increase in biscuit
hardness can be attributed to the dilution and weakness
of the gluten network caused by data press cake.
The Scanning Electron Micrograph showed the effect
of date press cake fibers on cross-sectional areas of the
control biscuits and the DPC-fortified biscuits. As we
can see in Fig. 2, their structures were slightly different.
The cross-sectional area of the control biscuits showed
gaps and air cells, compared to that of the fortified
sample. Also, we found that the fortified vegan biscuits
had an increased cell size, as well as bulged and thicker
cell walls.
Our results agreed with those of Dar et al. [30] who
studied carrot pomace powder-based extrudates. They
reported that as the concentration of powder increased,
the size of air bubbles and moisture droplets became
smaller, resulting in a tough product. They also found
that the presence of additives such as fiber and sugar had
a pronounced effect on the expansion of cookies.
In another study, supplementing cookies with date
and peach powder (2, 4, and 6 %) increased cell size and
caused a rough structure with fractured fibers and starch
granules that got reoriented to shape the cookies [31]. At
a 6% supplementation, the cell walls became bulged and
thicker.
Microbiological assay. Table 8 illustrates various
microorganisms (total bacteria count, yeast and mold
count, CFU/g) in the vegan biscuits and innovative
vegan protein bars partially supplemented with date
press cake powder over a storage period of 8 months.
We did not detect any bacteria in the biscuit samples in
the zero time since high baking temperatures killed all
the microorganisms. After 2 and 8 months of storage,
the bacterial counts were 1.6×102 and 7.0×102 CFU/g for
the control biscuits, respectively, and 1.1×102 and 4.0×102
CFU/g for the DPC-fortified biscuits, respectively.
Yeasts and molds were not detected after 2 months
of storage for the control and after 4 months
of storage for the fortified samples. The yeast
and mold counts for the control biscuits were
4.0×102 and 2.6×102 CFU/g after 4 and 8 months
of storage, respectively, whereas for the fortified
biscuits they amounted to 3.0×10 and 1.1×10 CFU/g
after 6 and 8 months of storage, respectively. Microbial
contamination can be caused by the worker’s
contaminated hands during handling or by increased
temperatures during storage [32]. Our results were very
low compared to the WHO Standard (1994), which
established the maximum permissible limits for total
plate count and yeast and mold count to be 2.0×105 and
< 1.0×104 CFU/g–1, respectively, in baked products (cake,
bread, and biscuit) [33]. Thus, our biscuits had a lower
microbial profile and therefore were safe to consume.
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The shelf life analysis of the innovative vegan
protein bar detected no bacteria after 2 and 4 months.
Bacterial growth was detected after 6 months, while
yeast and mold were detected after 8 months of
storage at room temperature 25 ± 5°C. This means
that the quality of our innovative bars was quite
stable and they may be considered safe to consume.
Our findings were in agreement with Pratiwi et al.
who indicated that formulated products were safe
for consumption if yeast and mold were lower than
102 CFU/g and total bacterial count was lower than
1×103 CFU/g, as based on the Thai Community Product
Standard (TCPS 709/2004) [34].
CONCLUSION
Our study clearly showed that using date press cake
powder to produce vegan biscuits and protein bars is
practical, economic, and healthy since these products
have a high nutritional value and technological quality.
They contained high proportions of the recommended
dietary allowances for most of the studied nutrients for
adolescents and athletes and are especially useful for
vegetarians.
CONFLICT OF INTEREST
The author declares no conflict of interest regarding
the publication of this research.

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