ArticlePDF Available

Utilization of olive pomace as a source of bioactive compounds in quality improving of toast bread

Authors:
Egypt. J. Food. Sci. Vol. 48, No.1, pp. 27-40 (2020)
OLIVE oil pomace is produced as by-product with a large quantity during olive oil
processing. It is a promising source for polyphenolic compounds and fibers which could
be used in food industry. In this work proximate chemical analysis of olive pomace (two-phase
olive oil extraction) was studied. Also, seven extracting solvents were tested in extracting the
phenolic compounds from the olive pomace (OP). Total phenolic, flavonoids, and flavonols
contents of the different extracts were determined. In addition to, the antioxidant activity of
the phenolic extracts was investigated using 2, 2-diphenyl-1-picrihydrazyl (DPPH) to assess
the extracting efficiency of solvents. The obtained data rivaled that protein, fat, ash and fiber
contents of OP were 2.48, 2.33, 1.33 and 20.37% (FW), respectively. It is clear that the OP
contains a large quantity of fibers and it had cellulose content about 40.7% of the fiber content.
Furthermore, the total phenolic content was varied in the various extracts and ranged from
8.29 to 36.24 mg GAE g -1. While, total flavonoids were ranged from 2.23 to 12.52 mg QE g-1.
Methanol and water (80:20) recorded the highest antioxidant activity with EC50 of 1.373µg/µg
DPPH while, the acetone extract recorded the lowest antioxidant activity with EC50 of 8.052µg
/µg DPPH. Toast bread was fortified with the cellulose isolated from OP at three replacement
levels of 2, 4, and 6% and the results showed no significant differences between control sample
and the sample fortified with 2% cellulose in most of sensory characteristics tested. Addition
of pomace cellulose at replacement level of 2% enhanced the texture of the bead and was more
acceptable than the control. The results concluded that olive pomace is a good source for dietary
fibers and polyphenolic compound which could be used in the food industry.
Keywords: Olive pomace, Bioactive compounds and Toast bread.
3
Utilization of Olive Pomace As A Source of Bioactive Compounds
in Quality Improving of Toast Bread
Khaled A. Sleim1*, Waleed Z. Badawy2 and I. Smetanska3
1Food science and technology Department, Faculty of Agriculture, Fayoum University,
Egypt
2Food Technology Department, Faculty of Agriculture, Kaferelsheikh University,
Egypt
3Department of Plant Food Processing, Agricultural Faculty, University of Applied
Science Weihenstephan-Triesdorf, Weidenbach, Germany
Egyptian Journal of Food Science
http://ejfs.journals.ekb.eg/
*Corresponding author email: kas00@fayoum.edu.eg.
Received:22/1/2020; accepted:27/2/2020
DOI: 10.21608/EJFS.2020.22871.1038
©2020 National Information and Documentation Centre (NIDOC)
Introduction
Olive oil showed very interested nutritional
and sensorial properties due to its contents
of unsaturated fatty acids and polyphenolic
compounds which act as natural antioxidants to
protect human body (Paz Aguilera et al., 2005). In
addition to antioxidant activity of olive phenolic
compounds, it was found to have antifungal
activity (Winkelhausen et al., 2005). Extraction
process of the olive oil production generates a
considerable quantity of by-products which could
cause serious environmental problems due to its
very high organic loads (Roig et al., 2006). Those
by-products found to consist of sugars, pectin,
lipid, tannins and polyphenolic compounds.
Utilization of it as a raw material for producing
a high value compounds is particularly attractive
way to reuse it (Niaomakis and Halvadakis, 2004).
Three different kinds of by-products are
produced during the olive oil production
depending on the production method used.
(Fenandyez-Bolanos et al., 2006). The traditional
28
Egypt. J. Food Sci. 48, No.1 (2020)
KHALED A. SLEIM et al.
press method generates three phase and two by-
products: olive oil about (20%), solid by-product
(olive cake) around (30%) and waste water
about (50%) of the olive fruits (Jerman Klen and
Mozetic Vodopivec, 2012). On the other hand,
the two-phase extraction system generates olive
oil and one by-product which is a combination
of liquid and solid. This by-product contains
about 80% of the olive fruit which include pulp,
skin, seeds and pieces of stones (Vlyssides et al.,
2004). The by-product in this production method
(olive pomace) differs in its chemical properties
compared to olive cake from the traditional
three-phase extraction method. It has higher
moisture content ranged from 65-75% compared
to 22-25% for the olive cake (Alburquerque et
al., 2004). OP is the major output from the two-
phase extraction method it is a good source for
bioactive compounds which could be used in
food manufacturing as well as pharmaceutical
fields. Because of the high-water content of olive
pomace, the concentration of water soluble salts
and phenolic compounds in it were higher than
that of the olive cake produced by the three-phase
extraction system (Dermeche et al., 2013). Those
bioactive compounds could have new application
in foods and cosmetic industries (Rodrigues et al.,
2017).
The quantity of olive pomace generated
during production of olive oil is ranged from 2.75
to 4 tons for each ton of oil depending on fruit
quality, and extraction technology (Rorja et al.,
2006 and Conterno et al., 2017). OP was found
to have a considerable amount of polyphenoilc
compound. It was reported that about 89% of
olive fruit phenolic compounds remains in olive
pomace for which the functional properties of
olive oil and olive pomace are related (Ghanbari
et al., 2012). Olive pomace phenolic profile has
been studied and found to be fared according to
many factors including, fruit ripening, climatic
condition, cultivar, origin, and the extraction
system (Obied et al., 2008). Some authors found
oleuropein and oleuropein derivatives as major
compounds (Cioffi et al., 2010). Other researchers
reported different major compounds, namely
hydroxytyrosol as the main phenolic compounds
in olive pomace. (Alu’datt et al., 2010; Rubio-
Senen et al., 2012 and Nunes et al., 2018). The
major components in the olive pomace are
dietary fiber (including cellulose, hemicellulose,
lignin and pectin), protein, lipids, pigment, and
polyphenolic compounds (Di Gioia et al., 2002).
The inclusions of fibre in the food’s formulation
will inevitably bring about certain changes to
the product. Utilization of OP to obtain natural
ingredients like phenolic compounds and dietary
fibers to develop new food products is a proms
subject (Nunes et al., 2018).
Cellulose is insoluble in cold or hot water
and in hot dilute acids or alkalis. (Singanuson et
al., 2014). Powdered cellulose used in many food
applications, essentially in functional bread, to
increase fibre content and to decrease nutritional
value of the bread. Addition of cellulose to the
bread formulation, results in many changes in the
quality properties of the bread (Poran et al., 2008).
It is increasing the viscosity of the liquid mixture
of flour because its insolubility in water. This leads
to form a stronger gas holding structure. Thus, the
air bubbles will remain in small sizes and will not
float on the surface of the liquid, which results
in the product having accurate air bubbles, larger
foam size and better stability (Wongsonsarim et al.,
2001).. cellulose powder was announced to use as
a bulking agent in drink products, meat products,
salads, and especially baked and cereal products.
In this current work, various extracting
solvents were tested for extracting the phenolic
compounds from tow-phase extraction olive
pomace. Total phenolic, flavonoids, flavonols
contents were also determined and identified
using HPLC/DAD- MS. The antioxidant activity
of the different phenolic extracts was investigated
using DPPH method. Cellulose was isolated from
the OP as functional food ingredient and used at
different concentrations in toast bread formulation
to investigate its effects in the quality proprieties
of the produced toast.
Materials and Methods
Materials and reagents
Olive pomace (4 kg) from tow-phase
extraction olive oil unit was acquired from
olive production factory in Fayoum, Egypt. The
sample was homogenized and stored at -20º C
until analysis. All chemicals used were analytical
grade and purchased from sigma-Aldrich, Berlin,
Germany
Proximate chemical analysis
Moisture content was determined using oven
at 50°C under vacuum for 48 hr and the dried
sample was ground to fine powder for using
in farther analysis. Fat, total protein, ash, and
fiber of OP and toast bread were determined
according to (AOAC, 2012). Total protein
content was calculated using 6.25 as the nitrogen
conversion factor (Nunes et al., 2018). Available
carbohydrates were calculated by difference.
29
Egypt. J. Food Sci. 48, No.1 (2020)
UTILIZATION OF OLIVE POMACE AS A SOURCE OF BIOACTIVE COMPOUNDS ...
Extraction of phenolic compounds from olive
pomace
The dried Olive pomace was first extracted
which n-hexane in at ratio (1: 4 W/V) three times
successively to remove the residuals of fats and
pigments. Then, the polyphenols were extracted
from the OP using varies extracting solvents
including acetone, ethanol, ethanol and water
(50:50), methanol, methanol and water (80: 20),
ethyl acetate, and water at solvent to pomace ratio
(10: 1). The extraction process was cured out in a
shaker at room temperature for 24 hr followed by
filtration. The residues were re-extracted under the
seam conditions. The total extracts were filtered
(0.45 µm) and the solvents were evaporated at
35°C. in a Speed Vacuum Concentrator, SPD111V
230 (Thermo scientific, USA). The yield was
calculated and stored in dark at -20 oC until used
(Alu’datt et al., 2010).
Determination of total phenolic content
Total phenolic content of the extracts was
determined spectro-photometrcally with Folin–
Ciocalteu assay (Vergani et al., 2014). A 20 µL
aliquot of extracts solutions were mixed with 100
µL of Folin–Ciocalteu’s reagent followed by 1.586
mL of distilled water and followed by 300 µL of
20% Na2CO3 solution. The obtained mixtures
were incubated in a shaking incubator at 40 °C
for 30 min and the absorbance was measured at
765 nm. The results were expressed as mg gallic
acid equivalent (GAE) using the following liner
equation based on gallic acid calibration curve.
Y = 0.0248x + 0.237 (R² = 0.997)
Where A is the absorbance and C is the

Determination of total flavonoids and flavonols
Total flavonoids content was determined
as described by Mohdaly et al. (2009). Using
AlCl3 ethanolic solution and the absorbance was
measured at 420 nm. Total flavonoids content
calculated and expressed as quercetin equivalent
(QE) using the following equation based on the
calibration curve:
Y = 0.0035x + 0.0258 ((R² = 0.9929)
Where Y is the concentration (mg QE/100
g extract) and X is the absorbance and Total
flavonols content was determined according to the
method described by Kumaran and Joel (2007). 2
mL of 20 g/L AlCl3 ethanolic solution and 3 mL
of 50 g/L sodium acetate solution were added
to 2 mL of extract solution. The absorption was
recorded after 2.5 hr at 440 nm. Total flavonols
content expressed as QE was calculated using the
quercetin calibration curve:
Antioxidant activity of olive pomace extracts
The antioxidant capacity pomace extracts were
determined using 2,2-diphenyl-1-picrihydrazyl
(DPPH) assay according the method of Brand-
Williams et al., (1995) with some modifications.
Extracts and synthetic antioxidants (BHA, BHT
and TBHQ in ethanol) solutions of different
concentrations (100µL of each) were vortexed
for 30 s with 1.8 mL of DPPH solution and left
to react for 30 min, after which the absorbency
of the remaining DPPH was recorded at 515
nm. A control sample was prepared at the same
conditions without extract. The measurements
were performed in triplicate. Scavenging activity
was calculated as follows:
scavenging (%) = [(A. control – A. sample) /A.
control] × 100
Where : A is the absorbance at 515 nm.
Antiradical Efficiency = 1/EC50
EC50 is extraction concentration providing 50%
inhibition of DPPH.
High performance liquid chromatography
(HPLC/DAD)
HPLC was performed in LC10 AD HPLC
eluent pump (Shimadzo, Kyoto, Japan), DAD
SPDM10 AVP, UV-Vis SPD 10AVP detectors
(Shimadzo, Kyoto, Japan). phenolic compounds
were separated on a C18 analytical column, 250
.46 mm i.d. (Shimadzo, Kyoto, Japan) packed
with Luna C18 stationary phase, particle size
3µm and connected to C18 precolumn. The time
of HPLC run was over 40 min. UV-Vis detector
was operating at 290 nm wavelength. Phenolic
compounds were identified by comparison of
chromatographic retention times and area of
the peak in the extract with that of the standard
phenolic acids and reference compounds using
Mass Lynx 4.0 software (Micromas UR Ltd., UK)
and the available literature data (Gheldof et al.,
2002).
Determination of cellulose content
This was achieved by delignification of the
sample with chlorous acid followed by elimination
of hemicellulose by treatment of the resulting
holocellulose with 10 % NaOH at 80°C for 3
hours as reported by Chen et al. (1988) as follows:
The lignocelluloses material was first subjected to
Soxhlet extraction with a mixture of methanol and
benzene (1:1) for 8 hr lignin was then eliminated
30
Egypt. J. Food Sci. 48, No.1 (2020)
KHALED A. SLEIM et al.
treating 5.0 grams (oven dry) of olive cake with
sodium chlorite solution (sodium chloride 1.5
gram in 160 mls. of water containing 10 drops
of glacial acetic acid). The mixture was left
in water bath at 70°C for one hour then after,
ten drops of glacial acetic acid and 1.5 gram
of sodium chlorite were again added and this
was repeated twice. After filtration the residual
material was washed successively with water
and ethyl alcohol to give the holocellulose.
For the removal of hemicellulose, the obtained
holocellulose was treated 10 % NaOH solution
(1:20 W/V) and heated at 80°C in a water bath
for 1.5 – 3.0 hour. After filtration, the residue
was washed with water, ethanol and ether and
then dried at 105°C to constant weight.
Determination of hemicellulose content
Hemicellulose content was estimated,
gravimetrically, after extraction, as reported
by Chen et al. (1988) 10 grams of olive cake
with 14 % NaOH (100ml) at 90ºC for 3 hr, and
precipitated with HCl at PH 5. The precipitated
hemicellulose was separated by centrifugation,
washed with ethanol, then dried and weighted.
Determination of lignin content
Lignin content in the investigated materials
was also determined according to the method
described by Fahmi (1984) as follows: One
gram olive cake extracted using a mixture of
methanol and benzene (1:1). In a wide mouthed
bottle of 150 ml capacity, 50 ml of 38% pure
HCL (not less than 38%) was added. The
mixture was left for two min, and then 50 ml
of concentrated sulfuric acid was added. After
shaking for one hour the mixture was left for 24

of one-liter capacity. The bottle was washed
with 415 ml of distilled water and filtered.

weighted.
Cellulose isolation
The isolation of cellulose was cured out
using the methods described by Brendel et al.
(2000) as follows: 500 gram of dried olive cake
was extracted with aqueous acetic acid 80%
(w/w) and nitric acid 70% (w/w). The residue
was then thoroughly washed with distilled
water and ethanol 95% to remove the nitric
acid and extraction breakdown products. The
residue was then dried in an oven at 60 ºC for
16 hr and was labeled as cellulose.
Determination of dough rheological properties
The effect of powdered cellulose on
rheological properties of dough during mixing
was determined by the Brabender Farinograph,
following the AACC Approved methods (54
– 21, 1983) and the Brabender Extensigraph
following the AACC Approved methods (54 –
10, 1983).
Bread making
The Straight Dough (Bulk Fermentation)
method was used for bread making as described
by Pourabedin et al. (2017), the amount of
added water was calculated from Table 6. The
control sample was consisted of 100 g flour, 1.5
g salt, 1g yeast. Three treatments ware prepared
with three different replacement levels 0, 2, 4
and 6 % of the flour. Dough pieces (100 ± 0.1
      

25 min.
Sensory evaluation
Toast bread containing different cellulose
powders and control bread were sensory tested
in Food Technology Department, Faculty of
Agriculture, Kaferelsheikh University, Egypt.
For their color, appearance, odor, texture, taste
and overall acceptability on a 1 to 10 hedonic
scale as described by Meilgaard et al. (2007).
Statistical analysis
Statistical analysis of the data obtained
from the study was performed using the SPSS
v statistical program SPSS v. 16 for windows
(SPSS, Chicago, II., USA) The ANOVA method
was used to analyze the results. Multiple range
tests from Duncan were used at a level of 5% of
significance for comparison of means. All trials
were conducted in triplicate.
Results and Discussion
Proximate chemical composition of olive pomace
The main values obtained for the proximate
composition of OP are presented in Table 1.
The results showed that the sample presented
a moisture content of 64.58% (FW) and protein
content of 2.48%. The data rivaled that ash
and fiber content of OP was 1.33 and 20.37%
(FW) respectively. The total lipid of the
analysed sample was 2.33g/100g (FW) which
could be used in food and cosmetics industry
(Rodrigues et al., 2017). Di Giovacchino and
Prezioso, (2006) reported that ash content of
OP ranged from 1.42 to 4% (FW). It is clear
31
Egypt. J. Food Sci. 48, No.1 (2020)
UTILIZATION OF OLIVE POMACE AS A SOURCE OF BIOACTIVE COMPOUNDS ...
that the OP contains a large quantity of fibers
and it had cellulose content about 40.7% of the
fiber content. Several studies have focused on
isolation of dietary fibers from olive pomace
and reported cellulose, hemicellulos and lignin
as the main carbohydrates in olive by-products
(Jimenez et al., 1994). In another study, Vlyssides
et al., (1998) found that OP contains cellulose,
hemicellulos and lignin of 14.54, 6.68, and 8.54%
(DW) respectively. These compounds could be
used in many food products as gelling agents,
fiber source and fat substitute. It was found that
the proximate composition of OP is influences by
many factors including ripening stage, cultivar,
and agriculture practices (Portarena et al., 2017).
Our results agreed with that stated by Roselló-
Soto et al. (2015) and Nunes et al. (2018).
TABLE 1. chemical composition of olive pomace.
Olive pomace g /100g (FW)
 64.58± 2.51
Total lipids 2.33± 0.06
Protein 2.48±0.04
Ash 1.13±0.02
Total carbohydrates 29.48± 2.41
 20.37± 1.65
Cellulose* 40.77 ± 2.44
Hemicelluloses* 33.63±2.28
Lignin* 19.50± 1.79
 
dry weight basis)
TABLE.
Solvents Extract yield (g/
kg-1 DW)
Total phenolic
(mg GAE g-1 DW)
EC50
µg/µg DPPH
Antiradical

Methanol 115.85±0.22 24.64±0.05 2.337 0.428
Ethanol 98.68±0.21 18.22±0.04 4.416 0.226
Methanol: water (80:20) 141.27±0.28 36.24±0.10 1.373 0.728
Ethanol: water (50:50) 118.61±0.34 26.22±0.08 1.733 0.577
Ethyl acetate 80.51±0.17 9.04±0.02 5.821 0.172
Acetone 66.92±0.13 8.29±0.03 8.052 0.124
Water 94.58±0.19 19.50±0.07 2.795 0.358
Extraction of phenolic compounds from olive
pomace by different solvents
The majority of polyphenolic compounds
(98%) remain in the olive pomace and a small
fraction passes into the oil about (2%). (Chanioti
and Tzia, 2017). To extract the phenolic compounds
from OP, suitable solvents must be used according
to their extraction efficiency and according to the
uses of the compounds to be extracted. The effect
of various solvents was assessed to determine the
most appropriate one for yield, total phenoilc,
flavonoids, and flavonol content of the extracts
obtained. Polyphenolic yields were found to
increase with increasing the polarity of the solvents.
The extract yield was varied from 141.27 to 66.92
g / kg -1 (DW) (Table 2). The obtained results
proved that using methanol and water showed
highest yield , while acetone scored the minimal
polyphenol production (66.92 g / kg DW).
Referring to polyphenols from different
extracts, the results showed that the polyphenols
content varied from 36.24 to 8.29 mg/g-1.
Methanolic extract recorded the highest total
polyphenolic content higher than the other solvents
While, hand, acetone extract presented the less
polyphenolic contents. This because of the high
polarity of methanol. The obtained findings similar
to those obtained from other researchers who used
several solvents to extract phenolic compounds
from olive and olive pomac. (Cioffi et al, 2010,
Lafka et al, 2011, Vergani et al, 2016, Araújo , 2015
and Albahari et al., 2018). Cedola et al. (2019)
found that dry olive paste had phenols content,
equal to 45.09 mg GAE/g dw, and high amount of
flavonoids (36.11 mg QE/g dw).
32
Egypt. J. Food Sci. 48, No.1 (2020)
KHALED A. SLEIM et al.
Total flavonoids and flavonols content of olive
pomace extracts
Total flavonoids and flavonols content
of olive pomace extracts were determined to
identify the quality and the structure of the OP
phenolic compounds. Because of the antioxidant
efficiency dose not correlate with the quantity of
the phenolic compounds in all cases. The results
are presented in Fig. 1. The results indicated that
flavonoids and flavonols content were varied with
the different extracts. Total flavonoid contents
ranged from 12.52 mg/g-1 (DW) for methanol +
water extract to 2.23 mg/g-1 (DW) for acetone
extract. Regarding to the flavonols contents,
methanol + water and ethanol+ water recorded the
highest content with values of 6.73 and 5.72 mg/
g-1 (DW) respectively. On the other hand, aceton
and ethyl acetate recorded the lowest flavonoids
and flavonol contents of the olive pomace.
Identification of polyphenolic compounds from
methanol: water extract of olive pomace
The phenolic compounds and derivatives
of olive pomace methnolic extract in this study
were fractionated an identified by HPLC/DAD.
The protective chromatogram obtained at 290nm
along with the corresponding retention time,
peaks number and beak relative area are presented
in Fig. 2 and Table 3. The prime polyphenolic
found in the studied extract are phenolic-acids,
phenolic-alcohols, secoiridoid derivatives, and
flavonoids. The major phenolic acids were galic,
 
acid showed the highest concentration, while
galic acid and cinnamic acid recorded the lowest
concentration in the methanolic pomace extract.
Many factors were found to affect the phenolic
compounds concentrations including the cultivar,
agronomic, geographic origin of olive, olive tree
irrigation, and technological conditions of oil
production (Servili and Montendoro, 2002). These
results agree with those reported by Vincenzo
(2016) and Cioffi et al. (2010).
The chromatogram of olive pomace brings to
light the presence of hydroxytyrosol and tyrosol
as phenolic alcohols and oleuropein, ligstroside
aglycone, and oleuropein aglycone as secoiridoid
derivatives. Hdroxytyrosol have been revealed
to be one of the most interesting phenolic
compounds in the olive pomace, because of its
strong antioxidant activity, anti-inflammatory
and antimicrobial properties (Robles-Almazan,
2018). Moreover, this compound affects the
quality properties (sensory and chemical) of food
products was explored (Nunes et al., 20180).
Oleuropein and oleuropein aglycone were found
in olive oil and olive pomace (Fernendez-Bolanes
et al., 2006, Goldsmith et al., 2014, Leouifoudi
et al., 2014. and Sicari, 2016). Oleuropein also
works as natural anti-oxidant in the body (Visioli
et al., 2006). The results showed the presence
Rutin and luteolin as flavonoids derivatives in the
olive pomace. According to the literature data,
these compounds were detected in olive oil and
olive by-products (Dermeche et al., 2013).
Antioxidant activity of olive pomace extracts
Because of the undesirable effects of the
synthetic antioxidants on human health and
enzymes systems, the natural antioxidants
can replace the synthetic one (Monica et al.,
2007 and Baydar et al., 2007). The results
of scavenging effects of the OP extracts are
summarized in Fig. 3. It could be notice that
inhibition ratio is increases by increasing the
concentrations of extracts for all tested extracts.
when low concentration 50µg/mL was used,
the remaining DPPH hanged from 93.63% for
acetone extract to 60.38% for methanol+water
extract. Meanwhile, when the concentration was
increased to 300 µg/mL the remaining of DPPH
was decreased to 64.72, 8.38, and 6.65% for
acetone, ethanol +water, and methanol+water
extracts respectively. These results may be
due to the elevated polyphenolic content in
methanol and ethanol extracts. Our findings
are compatible with that stated by (Silva et al,
2006, Obied et al., 2007, and Leouifoudi et al.,
2014).
The results in the same figure illustrate
the scavenging activity of the OP extracts
at different concentrations compared to the
synthetic antioxidants (BHA, BHT, and BHTQ).
Scavenging activity of OP was found to be
concentration dependent. The results showed
that methanol+water and ethanol+water had
high scavenging activity as strong as BHA and
BHT and recorded EC50 values of 1.373 and
1.728µg/ µg DPPH and antiradical efficiency
values of 0.728 and 0.577, respectively. The
results also proved that acetone extract showed
the lowest scavenging antioxidant activity with
EC50 value of 8.052µg/µg DPPH. The strong
scavenging activity could be related to the high
concentration of the antioxidant compounds
in OP such as hydroxytyrosol, oleuropein, and
oleuropein aglycon (Suarez et al., 2009 and
Leouifoudi et al., 2014).
33
Egypt. J. Food Sci. 48, No.1 (2020)
UTILIZATION OF OLIVE POMACE AS A SOURCE OF BIOACTIVE COMPOUNDS ...
5,0 10,0 15,0 20,0 25,0 30,0 35,0
-20
50
100
150
200
120330 #55
K87
m AU
min
1 - 8,327
2 - 11,403
3 -Caffeic Acid
4 - 13,923
5 - 14,973
6 - 15,637
7 - 16,390
8 - 16,983
9 - 17,423
10 - 18,473
11 - 18,807
12 -Cinnamic Acid
13 - 21,677
14 - 22,757
15 - 23,167
16 - 23,927
17 - 24,863
18 - 25,273
19 - 25,650
20 - 26,473
21 - 27,610
22 - 28,007
23 - 28,883
WVL:290 nm

Fig.2. HPLC–DAD chromatogram of olive pomace methanolic extract.
TABLE 3. Phenolic components of olive pomace methanolic extract.
No. R. T.
Min. Peak Name Height mAU Area
mAU*min
Relative Area
%
1 8.33 Gallic acid 2.893 1.390 1.22
2 11.4 Hydroxytyrosol 10.090 3.342 2.93
3 12.65  10.873 3.706 3.25
4 13.92 Cumaric acid 9.062 2.684 2.36
5 14.97 Tyrosol 84.547 23.963 21.03
6 15.64 Vanillic acid 6.272 1.652 1.45
7 16.39 Oleuropein 27.784 7.064 6.20
8 16.98 NA 8.605 1.999 1.75
9 17.42  6.360 2.967 2.60
10 18.47 NA 14.712 8.113 7.12
11 18.81 oleuropein aglycone 20.897 9.379 8.23
12 20.7 Cinnamic acid 4.391 0.691 0.61
13 21.68 NA 17.878 3.555 3.12
14 22.76 Ferulic acid 13.727 2.074 1.82
15 23.17 NA 4.207 0.748 0.66
16 23.93 NA 2.932 0.552 0.48
17 24.86 Oleuropein glucoside 48.869 12.416 10.90
18 25.27 Luteolin 40.621 8.189 7.19
19 25.65 Luteolin-7-glucoside 13.812 2.484 2.18
20 26.61 NA 4.130 0.688 0.60
21 27.61 Rutin 10.918 1.886 1.65
22 28.01 NA 6.671 1.217 1.07
23 28.88 NA 53.992 13.190 11.58
34
Egypt. J. Food Sci. 48, No.1 (2020)
KHALED A. SLEIM et al.
Sensory evaluation of toast bread samples
fortified with olive pomace cellulose
Cellulose is one of the main olive cell wall
polysaccharides recovered from olive pomace
(Catanakis et al., 2010). In food industry, the
valorization of native dietary fibers appears to be
     
have role in prevention of several diseases such
as cancer (Rodríguez et al., 2006). There are less
publications on the utilization of olive pomace
in foods especially its effects on the rheological
properties of the dough when used as a substitute
for wheat flour in bread making. In this part of
the study, isolated cellulose from olive pomace
was used in fortification of toast bread and its
effects on the rheological and sensory properties
of the bread was investigated.Results of sensory
evaluation of produced bread with different added
levels of OP cellulose are given in Table 4. It
indicated no significant differences between the
control and the sample fortified by 2% cellulose
in all the tested parameters. The results showed
that increasing the fortification ratio to 4% led to
no significant differences (p < 0.05) between the
control and the sample in color, taste and texture
and significant differences in, odour, appearance
and overall acceptability.
The bread with 2% substitution level was
superior in all sensory characteristics evaluated
compared to other replacement ratios. Moreover,
it recorded higher scores in texture, appearance
and overall acceptability than the control
sample. When 6% of the flour were replaced
with cellulose,significant drops in the values
of all the sensory characteristics were observed
in the resulting bread. Our results are similar
    
radical and comparing with synthetic antioxidants .
to that presented by Cecchi, et al. (2019) for
pasta, bread, and granola bar fortified with olive
pomace. Cedola et al. (2019) found that addition
of dry olive paste flour to the bread also slightly
interfered with the network formation, thus
influencing the final bread bubbles that were
considered more acceptable in the control samples
than in the enriched bread. The Sensory evaluation
of cellulose-enriched baked rolls indicated that
addition of cellulose by up to 1% was identical to
the control rolls. It was also found that increasing
the addition levels of cellulose significantly
reduced the crus, taste, porosity and color of the
produced rolls (Lauková et al. (2017). Likewise,
Gómez et al. (2003) mentioned that it is possible
to add dietary fibers to the flour while making
bread by up to 2% without. Ang and Miller (1989)
used cellulose powder in the cake manufacture
with different addition ratios and measured the
texture of the cake. They found that the low
levels of cellulose addition led to the cake being
produced more harder texture than those with a
high level of cellulose. This can be because long
fibers contribute to a soft cake. They also noticed
that these ratios from adding up to 4% improve
the overall appearance and reduce moisture loss
from the surface cracking as well as extending the
shelf life of the cake (Kamel and Stauffeer, 1993
and Prakongpan et al, 2002).
Quality characteristics of toast bread
Regarding to the effect of adding cellulose in
the bread formula in the chemical composition
of the produced bread, the results in Table 5
showed that moisture content of the bead was
increased with increasing the fortification level.
There were no significant differences between
35
Egypt. J. Food Sci. 48, No.1 (2020)
UTILIZATION OF OLIVE POMACE AS A SOURCE OF BIOACTIVE COMPOUNDS ...
the control sample and the sample fortified with
2% olive cellulose. As prospective, it was noted
that the bread samples to which cellulose was
added contained higher fibers than those made
without adding cellulose. Besides, the results
also demonstrated no significantly differences
among the control and the bread samples with 2%
and 4% added olive cellulose powder in protein,
lipid and ash contents. Our results were similar
to that obtained by Lin et al. (2017). For olive
pomace based high fiber biscuit. Sodchit et al.
(2013) added banana peel cellulose powder to
butter cake at three levels and found that addition
cellulose to the cake improved the fiber content of
the product. They also observed that sample with
1.5 % added cellulose recorded no significant
differences compared with the control in protein,
moisture, total lipid and ash contents.
Effect of addition of olive pomace cellulose on the
rheological properties of the dough
Farinograph characteristics
It was found that adding dietary fibers to the
bread improves the nutritional value, but at the
same time it may lead to a change in some of the
rheological properties of the dough, and this may
lead to an effect on the quality of the bread and the
sensory properties of bread (Rosell et al., 2005).
Farinographic properties of doughs with several
levels of olive pomace cellulose are given in Table
(6). Water is an important component of baking
dough because it takes part in hydration of gluten,
thus ensuring that the dough maintained carbon
dioxide. Also, the ability of dough to absorb water
(WA) is of great importance in bread industry.
The water absorption of dough with 2% olive
pomace cellulose substitution was 54.5% and it is
higher than that of control dough. When the olive
TABLE
Samples
Sensory characteristics
Color  Odour Texture Appearance Overall
acceptability
Control 9.20 ±0.15a9.23 ±0.37a9.04 ±0.34a8.20 ±0.39ab 9.11 ±0.22a8.23 ±0.27a
2 % OPC*8.8 ±0.38a8.92 ±0.54a8.91±0.12a8.90 ±0.18a8.95 ±0.32a8.53 ±0.44a
4 % OPC 8.75 ±0.29a8.85 ±0.42a8.17 ±0.19b8.10 ±0.32b8.38 ±0.17b8.16 ±0.14b
6 % OPC 7.94 ±0.41b6.81±0.22b6.90 ±0.71c7.43 ±0.54c6.82 ±0.27c7.14 ±0.19c
OPC= olive pomace cellulose
Extensograph properties
According to the results of extensographic
properties of doughs with added olive pomace
cellulose (Table 6), the controls sample recorded
the highest extensibility while the sample
substituted with 6 % cellulose showed the lowest
extensibility value. Thus, it can be observed that
addition of olive pomace cellulose caused the
extensibility of the dough samples to decrease.
Similar findings were reported by Koca and
Anil (2007) for replacement of wheat flour with
flaxseed flour in bread. Likewise, Poran et al.
(2008) found that addition of cellulose to the
wheat flour reduced the extensibility of dough.
This finding could be attributed to the protein
content decreases when flour is substituted by
powdered cellulose and as a result, the dough
loses portion of its expandability property.
A consequence, the dough loses part of its
extensibility property. Also, the dough demand
for water increased when fibre was added
and these led to dilution of gluten and reduce
extensibility of the dough. The resistances to
extension of dough samples are presented in
Table 6. The results indicated that there was a
highly significant increase in the resistance
of dough, when the flour was substituted with
powdered cellulose. The resistance of the dough
increased from for the control to for 6% cellulose
flour sample. Such increment in the resistance
could be due to the interaction between the olive
cellulose and gluten in wheat flour. Many studies
declared negative effect of adding insoluble fiber
on the formation of gluten network (Pourabedin
et al., 2017, and Ahmed et al., 2013). The energy
value of dough with 2% olive pomace cellulose
substitution was analogous to the control.
However, the energy values of doughs made
with 4% and 6% olive pomace cellulose were

36
Egypt. J. Food Sci. 48, No.1 (2020)
KHALED A. SLEIM et al.
TABLE
Samples
Chemical composition (%)
Moisture Protein Ash Total lipids Fiber Carbohydrates
Control 11.20±0.23b10.95±0.33b1.79±0.14a3.80±0.43a3.22±0.32d80.66±1.40a
2 % OPC 11.44±0.40b10.71±0.27b1.78±0.19a3.79 ±0.23a3.90±0.41c79.92±1.55a
4 % OPC 11.98±0.64a10.22±0.29ab 1.77±0.09a3.78±0.28a4.38±0.50b79.55±1.70a
6 % OPC 12.09±0.92a9.69±0.74a1.75±0.11a3.76±0.33a5.14±0.40a79.26±1.60a
OPC= olive pomace cellulose
Conclusion
This research confirmed that the quantity of
polyphenolic compoundst in the olive pomace
were ranged between 36.24 to 8.29 mg/g-1 DW
depending on the extraction solvent used. The
major polyphenolic compounds in the olive
pomace were tyrosol, hydroxytyrosol, oleuropein,
and oleuropein aglycon, luteolin and rutin. The
results showed that olive pomace methanolic
extracts had high scavenging activity as strong
as BHA and BHT which could be related to the
high concentration of the antioxidant compounds
in OP such as hydroxytyrosol, oleuropein,
and oleuropein aglycon. Adding olive pomace
cellulose powder to wheat flour led to significant
alters in farinograph parameters. Addition of 2%
cellulose powder enhanced the texture and the
acceptability of the toast bread compared with
the control sample, . It can be concluded that
TABLE
(82% extraction).
Farinogragh parameters
parameters
Samples
Water absorption
%Arrival time (min) Developing
time (min)
Stability time
(min)
Weakening
value (BU)
Control 53.6c0.5c1.0c4.50a70c
2% 54.5b1.5b2.0b3.52b80b
4% 56.9b1.5b2.25b3.51b80.5b
6% 66.8a2.2a3.1a3.04c90.7a
Extensograph parameters
Extensibility (mm)  proportional number Energy (cm2)
Control 125 445 3.65 63
2% 110 462 4.21 58
4% 101 468 4.63 48
6% 95 484 5.09 40
olive pomace cellulose could be used as wheat
replacer in toast making at the level of 2% with no
impairment on quality characteristics of the bread.
Acknowledgment
This study was financial propped by Cultural
Affairs and Missions Sector, Egypt and University
of Applied Science Weihenstephan-Triesdorf,
Weidenbach, Germany.
Referances
AACC. (1983) Approved methods of the AACC.
(Method 54-10). 8th ed. American Association of Cereal
Chemists, The Association, Saint Paul, Minnesota, U.S.A.
Ahmed, J., Almusallam, A.S., Al-Salman, F.,
AbdulRahman, M.H., Al-Salem, E., (2013)
Rheological properties of water insoluble date fiber
incorporated wheat flour dough. LWT - Food Sci.
Technol. 51, 409-416
37
Egypt. J. Food Sci. 48, No.1 (2020)
UTILIZATION OF OLIVE POMACE AS A SOURCE OF BIOACTIVE COMPOUNDS ...
Alburquerque, J.A., Gonzalvez, J., Garcia, D., and
Cegarra, J. (2004) Agrochemical characterisation
of ‘‘alperujo’’, a solid byproduct of the two-phase
centrifugation method for olive oil extraction.
Bioresource Technology, 91, 195-200.
Alu’datt, M. H., Alli, I., Ereifej, K., Alhamad, M.,
Al-Tawaha, A. R., and Rababah, T. (2010)
Optimisation, characterization and quantification
of phenolic compounds in olive cake. Food
Chemistry, 123, 117-122
Ang, J. F. and Miller, W. B. (1989) Enhancement of
cake volume by a new form of powdered cellulose.
Abstract AACC Annual Meeting. 74 (3), 162
AOAC, (2012) Official Methods of Analysis.
Association of Analytical Communities, USA.
Araújo, M., Pimentel, B. F., Alves, R. C., and Oliveira,
B.P. (2015). Phenolic compounds from olive mill
wastes: Health effects, analytical approach and
application as food antioxidants. Trends in Food
Science & Technology, 45, 200-211.
Baydar, N. G., Ozkan G., and Yasser, S. (2007)
Evaluation of the antiradical and antioxidant
potential of grape extracts. Food Control, 18, 1131-
1136.
Brand-Williams, W.; Culivier, M. E, and Berset, C.
(1995) Use of free radical method to evaluate
antioxidant activity. LWT- Food Science and
Technology, 28 (1), 25-30.
Brendel, O., Iannetta, P. M. and Stewart, D. (2000) A

Phytochemical Analysis, 11, 7–10.
Cecchi, L., Schuster, N., Flynn, D., Bechtel, R.,
Bellumori, M., Innocenti, M., Mulinacci, N.,
and Guinard, J-X. (2019) Sensory profiling and
consumer acceptance of pasta, bread, and granola
bar fortified with dried olive pomace (Patˆe):
A byproduct from virgin ´olive oil production.
Journal of Food Science, 84, (10), pp. 2995-3008.
Cedola1, A., Cardinali, A., Del Nobile, M. A. and
Conte, A. (2019) Enrichment of Bread with Olive
Oil Industrial By-Product. Journal of Agricultural
Science and Technology, B 9, 119-127
Chanioti, S., and Tzia, C. (2017) Optimization of
ultrasound-assisted extraction of oil from olive
pomace using response surface technology: oil
recovery, unsaponifiable matter, total phenol
content and antioxidant activity. LWT Food Sci.
Technol., 79, 178–189.
Chen, H.; Rubenthaler, G. L. and Schanus, E. G. (1988)
Effect of apple fiber and cellulose on physical
properties of wheat flour. Journal of Food. Science,
53, 304-305.
Cioffi, G., Pesca, M. S., De Caprariis, P., Braca, A.,
Severino, L., and De Tommasi, N. (2010) Phenolic
compounds in olive oil and olive pomace from
Cilento (Cam-pania, Italy) and their antioxidant
activity. Food Chemistry, 121, 105-111.
Contrerno, L., Martinelli, F., Tamburini, M., Fava, F.,
Mancini, A., Sordo, M., Pindo, M., Martens, S.,
Masiero, D., Vrhovsek, U., Dal Lago, C., Ferrario,
G., Morandini, M. and Tuohy K. (2017) Measuring
the impact of olive pomace enriched biscuits on the
gut microbiota and its metabolic activity in mildly
hypercholesterolaemic subject. Ers. J. Nutr. 1572-
1591
De Marco, E., Savarese, M., Paduano, A., and Sacchi,
R. (2007) Characterization and fractionation of
phenolic compounds extracted from olive oil mill
wastewaters. Food Chemistry, 104, 858- 867.
Dermeche, S., Nadoura, M., Larroche, C., Moulti-
Mati, F., and Michaud, P. (2013) Olive mill wastes:
biochemical characterizations and valorization
strategies. Process Biochemistry, 48 (10), 1532-
1552
Di Gioiam, D., Barberio, C., and Spagnesi S. (2002)
Characterization of four olive-mill-wastewater
indigenous bacterial strains capable of aerobically
degrading hydroxylated and methoxylated
monocyclic aromatic compounds. Arch
Microbiology, 178, 208–217.
Di Giovacchino, L., Prezioso, S. (2006) Utilization of
olive mill by-products. In: Proceedings of “Olive
.bioteq Recent advances in olive industry, 379–89.
Fahmi, R. (1984) Chemical investigation of some
different varieties of soybean grown in Egypt.
Ph.D. Thesis, Biochemistry Dept. Fac. of Science,
Cairo, Univ. Egypt.
Fernández-Bolaños, J., Rodríguez, G., Rodríguez, R.,
Guillén, R. and Jiménez, A. (2006) Extraction
of interesting organic compounds from olive oil
waste. Grasasy Aceites, 57 (1), 95-106.
Galanakis, CM., Tornberg, E., and Gekas, V. (2010)
   
olive mill wastewater and the gelling ability of the
   LWT- Food Sci Technol.;
43:1009–17.
38
Egypt. J. Food Sci. 48, No.1 (2020)
KHALED A. SLEIM et al.
Ghanbari, R., Anwar, F., Alkharfy, K. M., Gilani,
A-H., and Saari, N.(2012) Valuable Nutrients and
Functional Bioactives in Different Parts of Olive
(Olea europaea L.)-A Review, Int. J. Mol. Sci.; 13,
(3): 3291–3340.
Ghelof, N., Engeseth, N J., and Wang, X-H. (2002)
Identification and Quantification of Antioxidant
Components of Honeys from Various Floral
Sources. Journal of Agricultural and Food
Chemistry, 50, (21), 5870-7
Goldsmith, C.D., Stathopoulos, C. E., Golding, J.
B. and Roach, P. D. (2014) Fate of the phenolic
compounds during olive oil production with the
traditional press method. International Food
Research Journal, 21(1), 101-109.
Gómez, M.; Ronda, F., Blanco, C. A., Caballer, P.
A.and Apesteguía, A. (2003) Effect of dietary fibre
on dough rheology and bread quality. Eur. Food
Res. Technol., 216, 51–56
Gordon, M., Paiva-Martins, F., Almeida, M., (2001)
Antioxidant activity of hydroxytyrosol acetate with
that of other olive oil polyphenols. J. Agric. Food
Chem. 49, 2480-2485.
Hruškova, M. and Svec, I. (2017) Rheological
characteristics of composite flour with linseed
fiber-relationship to bread quality. Czech J. Food
Sci., 35, (5): 424-431.
Jerman Klen, T., and Mozetic Vodopivec, B. (2012)
The fate of olive fruit phenols during commercial
olive oil processing: traditional press versus
continuous two- and three-phase centrifuge. LWT.
Food Science and Technology, 49, 267-274.
Jiménez, A, Guillén, R, Fernández-Bolanos, J. and
Heredia, A. (1994) Cell wall composition of olives.
J. Food Sci., 59, 1192–6.
Kamel, B. S. and Stauffer, C. (1993) Advances in
Baking Technology. 1st ed., VCH Publisher, New
York, U.S.A
Charis M. Galanakis, M. C. (2011) Olive fruit
dietaryfiber: components, recovery and
applications. Trends in Food Science & Technology,
22 (2011) 175e184
Lafka, T-I., Lazou, A. E., Sinanoglou, V. J., and Lazos,
E. S. (2011) Phenolic and anti-oxidant potential of
olive oil mill wastes. Food Chemistry, 125 (1), 92-
98.

   
Effects of cellulose fiber with different fiber length
on rheological properties of wheat dough and
quality of baked rolls. Food Sci. Technol. Int., 23
(6), 490-499.
Leouifoudi, I., Zyad, A., Amechrouq, A., Oukerrou,
M.A., Mouse, H.A., and Mbarki, M. (2014)
Identification and characterization of phenolic
compounds extracted from Moroccan olive mill
wastewater. Food science and technology, 34 (2),
294-257.
Lin, S., Chi, W., Hu, J., Pan, Q., Zheng, B. Zeng, S.
(2017) Sensory and nutritional properties of chinese
olive pomace based high fibre biscuit. Emirates
Journal of Food and Agriculture. 29 (7): 495-501
Meilgaard, M.C., Civileand, G.V. and Carr, B.T. (2007)
Sensory Evaluation Techniques. 4th ed. CRC Press:
New York.
Mohdaly, A., Sarhan, M., Smetanska, E., and Mahmoud,
A. (2009) Antioxidant properties of various solvent
extracts of potato peel, sugar beet pulp and sesame
cake. Journal of Food Science and Agriculture, 90:
218-226.
Monica, D., Anthon, R., Guilia, C., Amaela, A.,
Alessandra, L., Francesco, V., Paoa, M., and
Assunta, M. (2007) Protective effect of olive oil
minor polar compounds against oxidative damage
in rats treated with ferric nitrilotriaceate. Food
Chemical Toxicology, 45, 233-240.
Niaounakis M, and Halvadakis P. (2004) Olive-
mill waste management: literature review and
patent survey, 1st ed, Typothito-George Dardanos
Publications, Athens
Nunes, M. A., Costa, A. S., Bessada, S., Santos, J.,
Puga, H., Alves, R. C., Freitas, V., and Oliveira,
M. B., (2018) Olive pomace as a valuable source of
bioactive compounds: A study regarding its lipid-
and water-soluble components. Science of The
Total Environment, 644, 229–236
Obied, H. K., Bedgood, D. R., Prenzler, P. D., and
Robards, K. (2007) Bioscreening of Australian olive
mill waste extracts: Biophenol content, antioxidant,
antimicrobial and molluscicidal activities. Food
and Chemical Toxicology, 45 (7), 1238-1248.
Obied, H. K., Prenzler, P. D., Ryan, D., Servili, M.,
Taticchi, A., and Esposto, S., (2008) Biosynthesis
and biotransformation’s of phenol-conjugated
oleosidic secoir-idoids from Olea europaea L.
Natural Product Reports, 25, 1167-1179.
39
Egypt. J. Food Sci. 48, No.1 (2020)
UTILIZATION OF OLIVE POMACE AS A SOURCE OF BIOACTIVE COMPOUNDS ...
Paz Aguilera, M. eltran, G., Ortega, D., Fernandez, A.,
Jimenrz, A., and Uceda, M. (2005) Characterization
of virgin olive oil of Italian olive cultivars: Frantoio
and Leccino grown in andalusia. Food Chemistry,
89, 387-391.
Poran, S., Goburdhun, D., Ruggoo, A. (2008) Effects
of adding cellulose on rheological characteristics of
wheat flour dough and on bread quality. University
of Mauritius Research Journal, 14, 112–128.
Portarena, S., Baldacchini, C., and Brugnoli, E. (2017)
Geographical discrimination of extra-virgin olive
oils from the Italian coasts by combining stable
isotope data and caroten-oid content within a
multivariate analysis. Food Chemistry, 215, 1–6.
Pourabedin, M., Aarabi, A. and Rahbaran, S. (2017).
effect of flaxseed flour on rheological properties,
staling and total phenol of Iranian toast. J. Cereal
Science, (76),173-178
Prakongpan, T. Nitithamyong, A. and Luanpituksa, P.
(2002) Extraction and application of dietary fiber
and cellulose from pineapple cores. Journal of
Food Science, 67 (4), 1308-1313.
Robles-Almazan, M., Pulido-Moran, M., Moreno-
Fernandez, J., Ramirez-Tortosa, C., Rodriguez-
Garcia, C., Quiles, J. L., Ramirez-Tortosa, M.C.,
(2018) Hydroxytyrosol: bioavailability, toxicity,
and clinical applications. Food Res. Int., 105, 654–
667.
Rodrigues, F., Nunes, M.A., and Oliveira, M.B.P.,
(2017) Applications of recovered bioactive
compounds in cosmetics and health care products.
In: Galanakis, C.M. (Ed.), Olive Mill Waste - Recent
Advances for Sustainable Management. Academic
Press, pp. 255–274.
Rodríguez, R., Jiménez A., Fernández-Bolan˜os, J.,
       
from vegetable products as source of functional
ingredients. Trends Food Sci. Technol., 17 (1),
3–15.
Roig, A., Cayuela, M., and Sanchez-Monedero, M. (2006)
An overview on live mill wastes and their valorization
methods. Waste Management, 26, 960-969.
Rosell, CM., Santos, E., and Collar, C. (2005) Mixing
properties of fiber-enriched wheat bread doughs:
A response surface methodology study. Eur. Food
Research and Technology, 223, (3), 323-340.
Roselló-Soto, E., Koubaa, M., Moubarik, A., Lopes,
R.P., Saraiva, J.A., Boussetta, N., Grimi, N., and
Barba, F.J. (2015) Emerging opportunities for the
effective valorization of wastes and by-products
generated during olive oil production process:
non-conventional methods for the recovery of
high-added value compounds. Trends Food Sci.
Technol., 45, 296–310.
Rubio-Senent, F., Rodriguez-Gutierrez, G., Lama-
Munoz, A., and Fernandez-Bolanos, J. (2012) New
phenolic compounds hydrothermally extracted
from the olive oil byproduct alperujo and their
antioxidative activities. Journal of Agricultural and
Food Chemistry, 60, 1175- 1186.
Servili, M., & Montedoro, G. (2002) Contribution of
phenolic compounds to virgin olive oil quality.
European Journal of Lipid Science and Technology,
104, 602–613.1
Sicari, V. (2017) Antioxidant potential of extra virgin
olive oils extracted from three different varieties
cultivated in the Italian province of Reggio
Calabria. Journal of Applied Botany and Food
Quality, 90, 76 - 82.
Silva, S., Gomes, L., Leitão, F., Coelho, A. V., and
Vilas Boas, L. (2006) Phenolic compounds
and antioxidant activity of Oleaeuropaea L.
fruit and leaves. Food Science and Technology
International, 12 (5), 385- 396.
Singanusong, R., Tochampa, W., Kongbangkerd, T.
and Sodchit, C, (2014) Extraction and properties
of cellulose from banana peels. Suranaree J. Sci.
Technol. 21 (3), 201-213.
Sodchit, C., Tochampa, W., Kongbangkerd, T. and
Singanusong, R. (2013) Effect of banana peel
cellulose as a dietary fiber supplement on baking
and sensory qualities of butter cake. Songklanakarin
J. Sci. Technol. 35 (6), 641-646, 2013
Suarez, M., Romero, M.-P., Ramo, T., Macia, A.,
and Motilva, M.-J. (2009) Methods for preparing
phenolic extracts from olive cake for potential
application as food antioxidants. Journal of
Agricultural and Food Chemistry, 57, 1463-1472.
Vergani, L., Vecchinoe, G., Baldini, F., Voci, A.,
Ferrari, F., Aliakbarian, B., Casazza, A., and
Perego, P. (2016) Antioxidant and hepatoprotective
potential of phenolic compounds from olive
pomace. Chemical Engineering Tansactions, Vol.
49, 475- 840.
Visioli, F., Poli, A., and Galli, C. (2002) Antioxidant
and other biological activities of phenols from
40
Egypt. J. Food Sci. 48, No.1 (2020)
KHALED A. SLEIM et al.
olives and olive oil. Medicinal Research Reviews,
22 (1), 65-75.
Vlyssides, AG., Loizidou, M., Gimouhopoulos, K.,
and Zorpas, A. (1998) Olive oil processing wastes
production and their characteristics in relation to
olive oil extraction methods. Fresen Environ Bull.
7, (5–6):308–13.
Wang, M., Hamer, R.J., Van Vliet, T., Gruppen, H.,
Marseille, H., Weegels, P.L. (2003) Effect of
water unextractable solids on gluten formation and
properties: mechanistic considerations. J. Cereal
Sci., 37, 55-64.
Winkelhausen, E., Pospiech, R. and Laufenberg, G.
(2005) Antifungal activity of phenolic compounds
extracted from dried olive pomace. Bulletin of the
Chemists and Technology of Macedonia, Vol.24,
(1): 41-46.
Wongsonsarim, C., Kowattanakul, T. and Donyasak,
B. (2001) Using cellulose powder from soybean
shell and greenbean shell in deep-fried dough stick.
Bangkok, Thailand: Chulalongkorn University,
Special problems.

 two phase extraction 

.2,2-diphenyl-1-picrihydrazyl (DPPH) 


           
 :
 


  







... If OMP is properly treated, it can be used in agriculture as an ecofriendly, high-quality compost because it contains a high organic matter content and a wide range of plant nutrients that can be reused as fertilizers for sustainable agricultural production (Chowdhury et al. 2013). Selim et al. (2020) used bioactive compounds derived from OMP to improve the quality of toast bread, and their findings are summarized in Table 1. ...
... Olive seeds and walnut shell are lignocellulosic in chemical structure. Olive pomace contains 40% cellulose and 19% lignin in its structure [35]. Lignin content in walnut shells is around 30% [36]. ...
Article
Full-text available
The most important advantages of adding additives to adhesives are increasing the bonding strength and reducing the adhesive cost. The desire to reduce costs as well as the need for environmentally friendly and health-friendly products have paved the way for the recycling of waste materials and the use of cheaper natural materials as additives. In this study, mussel, olive pomace, and walnut powders in different ratios (5%, 15%, and 30% by weight) and in different sizes (38 and 45 µm) were added to an epoxy adhesive. The steel materials were joined in the form of single-lap joints by using the obtained adhesives with additives. These joints were subjected to the tensile test and the strengths of these joints were examined. SEM images of the bonding interface were taken, and the distribution of the powders was examined. When the powder size was 45 µm, bond strengths increased in all additive ratios compared to the pure adhesive, while for 38 µm powders, the strength value increased only at the 5% additive ratio. In joints with 45 µm powder additives, the strength increased by up to 38% compared to the pure adhesive, while this rate was determined as 31% for 38 µm.
... If OMP is properly treated, it can be used in agriculture as an ecofriendly, high-quality compost because it contains a high organic matter content and a wide range of plant nutrients that can be reused as fertilizers for sustainable agricultural production (Chowdhury et al. 2013). Selim et al. (2020) used bioactive compounds derived from OMP to improve the quality of toast bread, and their findings are summarized in Table 1. ...
Book
Full-text available
The world's main challenge is to increase crop productivity in a sustainable manner. Every agricultural management decision should prioritize human health and environmental safety. Olive mill pomace (OMP) must be disposed of practically and affordably because it exacerbates environmental issues. If OMP is properly handled, it has the potential to be used in agriculture for sustainable production. Many approaches have been widely investigated in recent years as a result of environmental protection policy to improve the recycling of OMP through composting or use as fertilizers, biopesticides, and livestock feed. However, there was no comprehensive work that covered the role of OMP in improving soil properties, as well as sources of biopesticides and animal feed. The potential use of OMP as a fertilizer, biopesticide, and animal feed was discussed in this review. As a result, it was found that OMP can be utilized as a high-quality soil fertilizer. It may also be a viable alternative to synthetic pesticides for pest control, as it demonstrated a higher growth rate of beneficial insects. Furthermore, when using OMP as feed for animals showed a potential for tasty meats and healthy milk for ruminants and poultry without affecting their performance and viability. The most significant result of this review paper is that it contributes to the body of knowledge regarding the use of OMP as a sustainable and environmentally friendly product in the production of natural fertilizers, biopesticides, and animal feed.
... Olive pomace flour could represent a novel and low-cost alternative to wheat flour to enrich bakery products and obtain a healthier version of these snacks. Biscuits (Cecchi et al., 2019;Conterno et al., 2019;Lin et al., 2017;Ying et al., 2017) and bread (Cedola et al., 2019;Cecchi et al., 2019;Cedola et al., 2020;Selim et al., 2020) are characteristic examples of bakery products enriched with olive pomace. A single human intervention study demonstrated olive pomace role in alleviating metabolic condition consequences and provided an indication of its potential effect in improving the glycemic and lipid profiles in consumers with similar clinical conditions. ...
Article
Wheat flour is the major constituent of bakery products consumed as everyday snacks worldwide. However, due to its poor nutritional value, high gluten content, and rapid digestion has been linked to the onset of celiac disease, obesity, diabetes type II, and metabolic syndrome. Therefore, alternative flours from olive and grape by-products as well as pulses, such as chickpea, with higher nutritional value and prebiotic function have been exploited to enrich those products and possibly confer several health benefits due to their high bioactivity. To this end, the bioactivity of grape and olive by-products as well as chickpea is described. This study emphasizes the crucial function of the related compounds in human nutrition and metabolism, particularly in relation to post-prandial glycemia and lipidemia, as their acute perturbation is linked to the development of metabolic diseases. Dietary supplementation with either chickpea, olive or grape pomace extracts or powders in in vivo and in vitro studies demonstrated beneficial properties in terms of glucose and lipid metabolism management. Moreover, hepato- and cardio-protective, antioxidant, and anti-inflammatory properties were observed. Furthermore, fortification of bakery snacks with chickpea, olive, and grape pomace flours demonstrated promising results in improving the lipid and glycemic profiles in human intervention studies.
Article
BACKGROUND/AIM: Hypertension is a global public health problem and a leading cause of cardiovascular morbidity and mortality. In this paper, we study the effect of olive cake (OC) on blood pressure, endothelial dysfunction, redox status and vascular remodeling in dexamethasone-induced hypertensive (HT) rats. METHODS: HT rats were divided into two groups fed standard diet supplemented (HT-OC) or not (HT) with OC at 7.5% for 28 days. A control (C) was submitted to standard diet for the same experimental period. RESULTS: Systolic, diastolic and mean blood pressures were higher in the HT vs C and decreased in HT-OC vs HT. Aortic nitric oxide value was decreased in the HT vs the C and increased in HT-OC vs HT. Aortic lipid and protein oxidation products were higher in the HT than C and lower in the HT-OC vs HT. Aortic antioxidant enzymes activities were reduced in HT than control and increased in the HT-OC vs HT. The aortic wall thickness, medial cross-sectional area, media to lumen ratio and the number of VSMCs were higher in the HT and the OC has regressed vascular redemptions. CONCLUSION: In hypertensive rats, OC may alleviate blood pressure and arterial remodeling by suppressing oxidative stress, increasing antioxidant activity, improving endothelial function, preventing smooth muscle proliferation and thickening of the tunica media.
Article
Full-text available
Linseed fibre represents a rich natural source of dietary fibre. Here, we report that the addition of linseed fibre at levels of 2.5 and 5.0% changes the viscosity of wheat flour as well as the rheological properties of non-fermented and fermented dough. The differences recorded between fibre from golden and brown flax seeds (GF and BF, respectively) were not significant; BF caused a stronger increase in non-fermented dough elasticity. The addition of both variants reduced fermentation times and partially decreased dough volumes during the three phases of the fermentation process. The results of the baking test corresponded with the altered rheological parameters of dough. Based on principal component and cluster analyses, representative features for each rheological test were identified: amylograph maximum (amylograph test), the pasting temperature (RVA test), dough softening degree (farinograph test), extensigraph ratio (extensigraph test) were selected as the representative features. For the evaluation of fermented dough behaviour, wheat flour-linseed fibre composites could be differentiated according to fermentation time (fermentograph test) and dough volume (OTG test). Statistics also confirmed the appropriateness of the crumb firmness parameter for a detailed specification of bread quality.
Article
An olive pomace (pâté) obtained from virgin olive oil production, was used for the fortification of pasta, bread, and granola bar. For each food, a control (without pâté) and a fortified sample (with pâté, 7% in pasta and 5% in bread and granola bar) were manufactured. Descriptive analysis showed that pâté strongly affected the appearance of pasta and bread and increased the bitterness of bread and granola bar but not pasta. Granola bar was less affected in general, likely because of its higher ingredient complexity. In a central location test with 175 Californian consumers, both the control and the fortified samples of all three foods were well accepted overall, with only the mean liking of the appearance of the fortified pasta falling below the “neither like nor dislike” mark. Approximately 30% of consumers preferred the fortified sample over the control for each food and 50% were willing to pay more for the fortified products. The percentage of phenols from pâté recovered in the prepared samples was such that 63 g of pasta, 18 g of bread, and 12 g of granola bar would be sufficient to meet the EFSA health claim for olive oil phenols. This study demonstrates that pâté can be used for fortification of foods for human consumption, thus adding potential economic value to the virgin olive oil production chain and allowing for a higher daily intake of phenols from Olea europaea L., whose beneficial health properties are well recognized. The dried olive oil pomace (pâté) that we developed and tested in this research can be used to fortify pasta, bread, and granola bars with health‐beneficial phenols with only slight alterations of their sensory profiles and slight reduction in consumer acceptance. Virgin olive oil producers can use this byproduct and gain further economic value from olive oil production.
Article
Olive pomace is a major output of olive oil processing. This by-product is a valuable source of bioactive compounds with well-recognized benefits for human health and well-being. In this work, the proximate composition and the profiles of vitamin E (HPLC-DAD-FLD), fatty acids (GC-FID) and phenolics (HPLC-DAD-FL/MSn) were determined. Additionally, a sustainable process for antioxidants extraction - Multi-frequency Multimode Modulated (MMM) ultrasonic technique - was compared to a conventional solid-liquid extraction. The total phenolics content and antioxidant activity (ferric reducing antioxidant power and DPPH scavenging ability) of the extracts were analysed to assess the efficacy of both extraction methodologies. The vitamin E profile of the olive pomace comprised the vitamers α-tocopherol, β-tocopherol, α-tocotrienol and γ-tocopherol. α-Tocopherol was the major form (2.63 mg/100 g), while the other vitamers were present in amounts lower than 0.1 mg/100 g. The lipid fraction was especially rich in oleic acid (75%), followed by palmitic (10%), linoleic (9%), and stearic (3%) acids. Hydroxytyrosol and comsegoloside represented ≈79% of the total phenolics present in olive pomace. Hydroxytyrosol content was 83.6 mg/100 g, while tyrosol was present in lower amounts (3.4 mg/100 g). Concerning the antioxidants extraction, the MMM technique allowed a faster and higher recovery (p < 0.05) of the compounds, compared to the conventional solid-liquid extraction. By this way, it seems to be a very promising eco-friendly and effective methodology to extract antioxidants from this and other matrices.
Article
Many beneficial properties have been attributed to the Mediterranean diet. Over the years, researchers have attempted to learn which foods and which food components are responsible for good health. One of these components is hydroxytyrosol, an important phenolic compound present in olive oil. Hydroxytyrosol is a molecule of high interest to the pharmaceutical industry due to its anti-inflammatory and antimicrobial qualities its role against cardiovascular diseases and metabolic syndrome and for its neuroprotection, antitumour, and chemo modulation effects. The interest in this molecule has led to wide research on its biological activities, its beneficial effects in humans and how to synthetize new molecules from hydroxytyrosol. This review describes the vast range of information about hydroxytyrosol, focusing on its involvement in biological mechanisms and modulation effects on different pathologies. This review also serves to highlight the role of hydroxytyrosol as a nutraceutical and as a potential therapeutic agent.
Article
Olive pomace is the major by-products of olive processing industry, which is considered as a rich source of dietary fibre and other natural bioactive compounds. The present study aimed to develop Chinese olive pomace powders incorporated biscuit and evaluate its physical, sensory and nutritional properties. The results revealed that blends of wheat flour powder (85 g), Chinese olive pomace powder (15 g), sugar powder (33 g), shortening (22 g), sodium chloride (1.1 g), sodium bicarbonate (0.7 g), ammonium bicarbonate (0.3 g), skimmed milk powder (6 g), one egg and 12.5 mL water baked at temperature 200-220 °C for 8 min yielded dietary fibre enriched biscuit with acceptable texture and appearance. The sensory evaluation showed this newly formulated biscuit received an average score of 4.5(±0.58) on a 5-point hedonic scale, suggesting the biscuit has high overall acceptability. Besides, the nutritional quality evaluation also demonstrated this olive pomace incorporated biscuit contained abundant dietary fibre with significantly lower expected glycemic index compared to the traditional wheat flour biscuits. Taken together, the results suggested that incorporation of olive pomace powder in biscuit production could be used to develop functional food with enhanced fibre abundance, high nutritional quality and acceptability, and low calorie & glycemic index.
Article
Bread is a major human food throughout the world. The nutritional value of bread can be increased by adding different additives. Effect of adding brown flaxseed flour (10%, 20% and 30% w/w) to wheat flour on rheological properties of dough, including water absorption, stability and development time, extensibility and resistance to extension, was studied at 45, 90 and 135 min proving time. Qualitative properties of toast regarding staling (24 and 72 hours after baking) were determined and phenolic compounds and peroxide value of the breads were measured. The toasts were also tested for color indices. The results indicated that water absorption and development time increased as the proportion of flaxseed increased in dough. Stability decreased with the increment of flax flour compared to control sample (100% wheat flour). Extensibility and resistance to extension of flaxseed samples respectively decreased and increased comparing to those of control sample. Staling in toast with 20% flaxseed flour was seen to be lower than that of the control. Adding flax flour caused phenolic compounds to increase, however it decreased peroxide value. Bread color parameters L and a reduced by adding flax flour, while parameter b did not show significant different compared to the control (p<0.05).
Article
Powdered cellulose is often used in cereal processing industry. The effects of partial replacement (0.5%, 1%, 2% and 5%) of wheat flour by cellulose fiber with different fiber length (80, 120 and 220 µm) on rheological properties of wheat dough and qualitative parameters of baked rolls were studied. Sensory evaluation of baked products was also performed. Mixing and pasting properties of dough were determined by Mixolab. Generally, cellulose-enriched dough was characterized with higher water absorption, dough stability and parameters C2 and C3. Moreover, it was found that parameters C4 and C5 increased with increasing cellulose fiber length. From the results, it was also concluded that the physical parameters of baked rolls containing cellulose were reduced. It was also observed that the incorporation of cellulose fiber with shorter fiber length concluded in lower rolls volume compared to cellulose fiber with long fiber length. Texture analyses showed that the firmness of rolls containing cellulose at the substitution level 5% was significantly higher than those of the control, whereas the springiness of wheat rolls was not significantly affected. It was also recorded that the firmness and cohesiveness of baked rolls were higher after the addition of cellulose fiber with shorter fiber length. Sensory evaluation indicated that baked rolls with cellulose addition up to 1% were comparable with control rolls. Results also showed that higher levels of cellulose significantly decreased crust, taste, color and porosity of rolls.
Article
In this study, the physicochemical properties and bioactive compounds of olive oils from cultivars "Roggianella", "Sinopolese" and "Ottobratica", grown in the province of Reggio Calabria (Italy) have been evaluated. Polyphenols are a large family of compounds found in fruits and vegetables, which exhibit strong antioxidant activity by scavenging different families of Reactive Oxygen Species (ROS). Dialdehydic form decarboxymethyl oleuropein aglycon, hydroxytyrosol acetate, dialdehydic form oleuropein aglycon, pinoresinol, 1-acetoxypinoresinol, tyrosol and vanillic acid were the main phenolic compounds in all samples analyzed. Pinoresinol was the most abundant compound in the lignin fraction. In all oil samples analyzed the highest antioxidant capacity was attributed to Roggianella oil (36.85% I of DPPH and 4.07% I of ABTS) compared to Ottobratica (27.37% I of DPPH and 2.52% I of ABTS) and Sinopolese (18.33% I of DPPH and 1.72% I of ABTS). The main characteristics of the Roggianella cultivar were a very high concentration of total phenols (530 mg/kg of gallic acid) and α-tocopherol (211 mg/kg).
Article
The optimum conditions for ultrasound-assisted extraction of olive pomace oil were determined by response surface methodology (RSM). The effect of temperature, solid/liquid ratio and particle size was investigated on oil yield, its unsaponifiable matter (USM%), total phenol content (TPC) and antioxidant activity (DPPH). The optimal condition for the oil yield was: temperature, 60 °C, solid/liquid ratio, 1/12 g/mL and particle size, 0.5 mm. At this condition, the oil recovery was 11.03% which well matches with the predicted value. The optimal point for the USM% was achieved when the UAE is carried out at 55 °C using solid/liquid ratio 1/12 g/mL and particle size 0.5 mm. The optimal conditions for TPC of olive pomace oil obtained and its antioxidant activity were as follows: temperature, 50 °C, solid/liquid ratio, 1/8 g/mL and particle size, 0.9 mm and temperature, 55 °C, solid/liquid ratio, 1/8 g/mL and particle size, 0.9 mm, respectively. Close agreement between experimental and predicted values for USM%, TPC and DPPH was found.
Chapter
Life-expectancy has increased in developed countries, raising new concerns in skin appearance. Particularly, face wrinkles are one of the major features of aging leading to new researches for cosmetic active ingredients. A new tendency in cosmetic formulations is the use of raw materials from agroindustry by-products that normally are discarded as waste. Olive mill waste (OMW) is an olive oil by-product that represents a major environmental issue. Some studies have been carried out on this residue regarding phytochemicals identification and biological evaluation. The bioactive compounds present are mainly antioxidants (especially oleuropein), fatty acids (particularly monounsaturated fatty acids), and minerals. Indeed, taking into account its composition and sustainability issues, the recovery target compounds from these disposal residues is advisable. Particularly, cosmetic field may benefit from these materials. In this chapter, the challenging applications of OMW derived bioactive compounds as active ingredients for skin care products are reviewed and discussed.