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Sugar composition and yield of syrup production from the pulp of Moroccan carob pods (Ceratonia siliqua L.)


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The aim of this work is to provide a process for obtaining natural carob syrup of Morocco carob pods and their total and reducing sugar. Samples were collected from different regions in the agro-forestry system of Morocco. The total sugar and reducing sugar in pods obtained from different regions were 31.5–50.1 and 10.2–14.6g/100g “%w/w”, respectively. The yield of syrup from the different regions varies between 28.76 and 37.22g/100g “%w/w”. Populations from Essaouira and Beni-mellal have higher levels of sugar and yield of syrup. The values obtained vary according to the origin of the samples.
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Sugar composition and yield of syrup production from
the pulp of Moroccan carob pods (Ceratonia siliqua L.)
H. El Batal
, A. Hasib
*, A. Ouatmane
, F. Dehbi
, A. Jaouad
, A. Boulli
Laboratory of Environment and Valorisation of Agro-resources, Faculty of Science and Technology of Beni-Mellal,
University of Sultan Moulay Slimane, Morocco
Laboratory of Applied Organic Chemistry, Faculty of Science Semlalia, University of Cadi Ayyad Marrakesh, Morocco
Received 8 February 2011; accepted 10 October 2011
Carob pods;
Provenance of carob;
Pulp yield;
Total sugars;
Reducing sugars;
Syrup yield
Abstract The aim of this work is to provide a process for obtaining natural carob syrup of
Morocco carob pods and their total and reducing sugar. Samples were collected from different
regions in the agro-forestry system of Morocco. The total sugar and reducing sugar in pods
obtained from different regions were 31.5–50.1 and 10.2–14.6 g/100 g ‘‘%w/w’’, respectively. The
yield of syrup from the different regions varies between 28.76 and 37.22 g/100 g ‘‘%w/w’’. Popula-
tions from Essaouira and Beni-mellal have higher levels of sugar and yield of syrup. The values
obtained vary according to the origin of the samples.
ª2011 King Saud University. Production and hosting by Elsevier B.V. All rights reserved.
1. Introduction
The carob tree (Ceratonia siliqua L.), belonging to the family
Cesalpiniaceae sub-family of the family Leguminoseae, is
widely used in the Mediterranean regions (Battle and Tous,
1997; Yousif and Alghzawi, 2000), cultivated for ornamental
and industrial purposes (Girolamo and Laura, 2002).
World production is estimated at about 315 000 ton per
year, and the main producers for pulp, seeds, respectively,
are Spain (36%, 28%), Morocco (24%, 38%), Italy (10%,
8%), Portugal (10%, 8%), Greece (8%, 6%), Turkey (4%,
6%) and Cyprus (3%, 2%) of the world production (Chitt
et al., 2007).
The total area is approximately 200 000 ha and the yield
depends on crop, region and cultural practices (Makris and
Kefalas, 2004).
The carob distribution in Morocco is in the north selvage of
the Atlas chain, the Rif Mountain and in some valleys of the
south-west of the Anti-Atlas confined to arid and semi-arid
bioclimates with an extension to sub-humid bioclimate in some
stands (Sidina et al., 2009).
Chemical composition of the carob pod depends on varie-
ties, origin and harvesting time (Albanell et al., 1991). The
two main carob pod constituents are (by weight): pulp
(90%) and seed (10%) (Tous et al., 1995).
The seeds, covered with a tight-fitting brown coat, contain a
white and translucent endosperm (containing galagtomannans),
*Corresponding author.
E-mail address: (A. Hasib).
1878-5352 ª2011 King Saud University. Production and hosting by
Elsevier B.V. All rights reserved.
Peer review under responsibility of King Saud University.
Production and hosting by Elsevier
Arabian Journal of Chemistry (2011) xxx, xxxxxx
King Saud University
Arabian Journal of Chemistry
Please cite this article in press as: El Batal, H. et al., Sugar composition and yield of syrup production from the pulp of Moroccan
carob pods (Ceratonia siliqua L.). Arabian Journal of Chemistry (2011), doi:10.1016/j.arabjc.2011.10.012
also called carob gum, locust bean gum (LBG) or E411. Locust
bean gum is utilized in food and non-food industries for its abil-
ity to form a very viscous solution at relatively low concentra-
tion. It is also exploited for its synergy property with
carrageenan, agar and xanthan to form stronger and more elas-
tic gels (Hoichman et al., 2007).
Nowadays, the main application of the pulp is as an animal
feed (Manso et al., 2010). In human the carob pulp has been
used mainly as a cocoa substitute (Kumazawa et al., 2002; Ben-
goechea et al., 2008), in pharmaceutical products (Calixto and
Canellas, 1982) and ethanol production (Turhan et al., 2010).
The pulp of carob pods (fruit of Ceratonia siliqua L.) con-
tains high contents of sugar (sucrose, fructose and glucose) and
can be employed as a raw material for the production of syrups
(Petit and Pinilla, 1995) and crystallized sucrose (Lafuente,
1961) for the food industry.
The aim of the present work is to identify rich sugar carob
provenance to be used for industrial carob syrup extraction.
Figure 1 Repartition map of Moroccan carob population.
Table 1 Geographic and meteorological conditions of provenance of carob (Ceratonia siliqua L.) used in the study.
Provenance Geographic region Latitude N Longitude W Altitude (m) Rainfall (mm)
Taroudant High atlas (south-west) 303708200200–400 250
Agadir West coastal 304109330150–350 300
Essaouira –312009400100–200 300
Marrakech High atlas mountain 312907430700–1000 500
Beni-Mellal Middle atlas mountain 323006030500–800 550
Taza –340804080500–600 700
El Houceima North coastal 35110357050–250 327
2 H. El Batal et al.
Please cite this article in press as: El Batal, H. et al., Sugar composition and yield of syrup production from the pulp of Moroccan
carob pods (Ceratonia siliqua L.). Arabian Journal of Chemistry (2011), doi:10.1016/j.arabjc.2011.10.012
2. Materials and methods
2.1. Selection and preparation of samples
The material collection was carried out during summer. For
each provenance (Fig. 1) 30 trees were randomly chosen for
collection of composite samples. These later were characterized
according to the following morphological parameters: pod
weight, seed yield and pulp yield.
2.2. Determination of total and reducing sugars
Analyses of sugar in various food products are based on the
determination of total sugar, sucrose and reducing sugars, with
little emphasis on the other individual sugars. Precise, easy to
use and cost effective, the Bertrand’s method (Browne and
Zerban, 1955) of analysis remains a widely used industrial
method to estimate the total sugar and reducing sugar content
of syrups and other sugar solutions.
In this work, we used this method for the analysis of sugars in
the extracts of carob pulp. The assay itself involves collecting the
precipitate of cuprous oxide formed by reduction of the copper-
alkaline liquor in the presence of reducing sugars and assayed by
the manganimetric method. Bertrand tables give a direct corre-
spondence between the volume of potassium permanganate
(0.1 N) used and the reducing sugar content of the sample.
2.3. Production of syrup
For the production of syrup from the carob, the samples were
separated from the seeds and dried at 40 C for 1 day. In the
extraction process a sample weight of 100 g of pulp, with a
mean particle size between 0.5 and 1.0 cm, was suspended in
water in a ratio (pulp/water) (1:2) and stirred under optimum
conditions (T=43C, t= 160 min). The sugar extract and
solid phase were separated by centrifugation.
The juice obtained in the previous stage has to be concen-
trated using a rotary evaporator to the commercial levels of
66.5 Brix. The concentration of sugar must approach but not
quite reach the super-saturation point: The sugar concentra-
tion should be between 65% and 67% in weight. A lower per-
centage of sugar makes the syrup an excellent nutriment for
yeast and other microorganisms. A sugar saturated syrup leads
to crystallization of a part of the sugar under conditions of
changing temperature.
2.4. Statistical analysis
Each analysis was done at least in triplicate and the results are
expressed as mean and standard deviation (SD). The student’s
t-test was used to evaluate the differences between the means
of each group. P< 0.05 was considered to be statistically
3. Results and discussion
This work was carried out on different geographic regions of
carob trees in agro-forestry systems. Based on previous study
(Wahid et al., 2006) in which climatic data were analysed all
over Morocco, a stratified sampling method was used in which
topography, vegetation homogeneity and altitude were re-
grouped in seven geographic entities (Fig. 1). Each entity
(provenance) is here defined as a region characterized by sim-
ilar topographic and climatic conditions with a homogeneous
flora. Geographic characteristics, such as altitude slice, central
Figure 2 Yield of pulp and seeds of carob pods from different
Table 2 Measurement average of carob in this study and from other studies.
Country Seed yield
(g/100 g ‘‘w/w%’’ of carob pods)
Pulp yield
(g/100 g ‘‘w/w%’’ of carob pods)
Morocco (present work) 17.47–29.44 71.30–82.30
Portuguese (Barracosa et al., 2007) 12.00–14.00 86.00–88.00
Tunisia (Naghmouchi et al., 2009) 13.00–18.00 82.00–87.00
Spanish (Haselberg, 1988) 7.00–16.00 84.00–93.00
Turkey (Biner et al., 2007) 10.02–17.77 82.23–89.98
Figure 3 The overall mean values for the total sugar, reducing
sugar and syrup yield of carob pulp.
Sugar composition and yield of syrup production from the pulp of Moroccan carob pods (Ceratonia siliqua L.) 3
Please cite this article in press as: El Batal, H. et al., Sugar composition and yield of syrup production from the pulp of Moroccan
carob pods (Ceratonia siliqua L.). Arabian Journal of Chemistry (2011), doi:10.1016/j.arabjc.2011.10.012
latitude and longitude as well as the mean precipitation of
these provenances are summarized in Table 1.
3.1. Measurement of carob pods
Results of carob pod measurements are shown in (Fig. 2). The
overall mean values for all parameters measured and their
standard deviations are presented. High levels of variation
were found considering the seven provenances studied. The
data from this study showed that there were no significant dif-
ferences (P> 0.05) among the seven crops as far as the yield
of pulp and seeds is concerned (Fig. 2).
Data obtained from other studies (Table 2) showed a
high diversity in the yield of pulp and seeds of carob.
Moroccan crops are largely characterized by high seed yields
average [17.47–29.44 g/100 g ‘‘w/w%’’] content and medium
pulp yields average [71.30–82.30 g/100 g ‘‘w/w%’’]. Spanish,
Tunisian, Portuguese and Turkey crops produce low to
medium seed yields and medium to high pulp yields (Hasel-
berg, 1988; Barracosa et al., 2007; Biner et al., 2007; Nagh-
mouchi et al., 2009). The results obtained in this study,
however, were in agreement with the literature.
3.2. Total and reducing sugar values from pods
The overall mean values for the total sugar and reducing sugar
and their standard deviations were presented in (Fig. 3). The
total sugar content varied between 31.5 and 50.1 g/100 g ‘‘w/
w%’’ of dry pulp in populations of Agadir and Essaouira,
respectively. There was only one carob for Essaouira, which
values were the highest averages. In this study it was found
that no significant (P> 0.05) difference was observed between
Taroudannt,Marrakech,Beni-Mellal,Taza and El houceima.
Essaouira had a significantly (P< 0.05) higher total sugar
content than all the other crops (Fig. 3).
The levels of reducing sugars varied between 11.3 and 14.6 g/
100 g ‘‘w/w%’’ of dry pulp, respectively, in the regions of Agadir,
Marrakech and Essaouira. There was a relatively high average
value (14.6 g/100 g ‘‘w/w%’’ of dry pulp) among the native pop-
ulation of the West Coast (Essaouira). Taroudannt, Agadir,
Marrakech,Beni-Mellal and Taza did not differ (P> 0.05),
but significantly differed (P< 0.05) from El Houceima and
These results are comparable to those reported by Albanell
et al. (1991) in Spanish crops of about 46.95 and 12.75 g/100 g
‘‘w/w%’’ of dry pulp for total and reducing sugars,
3.3. Syrup yield
The results of syrup (66.5 Brix) yield obtained in experimental
conditions are presented in Fig. 3. The obtained average values
vary between 28.7 and 37.2 g/100 g ‘‘w/w%’’ of dry pulp. The
samples with the higher yield were from Essaouira and
Beni-Mellal, with averages of 37.21 and 36.61 g/100 g ‘‘w/
w%’’ of dry pulp, respectively. The regions with the lower yield
were Agadir and Taroudannt with averages of 28.76 and
29.27 g/100 g ‘‘w/w%’’ of dry pulp, respectively. No significant
(P> 0.05) differences were observed between the syrup yield
of Taroudannt, Agadir, Taza and El Houceima. The Essaouira
and the Marrakech differed from one another and from the
Taroudannt,Agadir and Taza. The Taroudannt was
significantly (P< 0.05) lower in syrup yield than the other
crops. These results are less than with those reported by Petit
and Pinilla (1995) in Spanish crops of about 54.24 g/100 g
‘‘w/w%’’ of dry pulp for the syrup yield.
4. Conclusion
The proportions of carob pulp and seeds and the contents of
total and reducing sugars in pulp show a great diversity be-
tween the populations of the Moroccan carob tree. This
diversity seems to take place according to the geographical
origin of the population. The obtained results are comparable
with those reported in other studies for cultivars of various
The obtained carob syrup yields ranging between 28 and
39 g/100 g ‘‘w/w%’’ of dry pulp are very interesting for indus-
trial exploitation. According to this study, the most interesting
samples for the production of high syrup yield are those col-
lected in the regions of Essaouira and Beni-Mellal.
Chitt, A., Belmir, H., Lazrak, A., 2007. Bulletin mensuel d’information
et de liaison du PNTTA MAPM/DERD 153, 1–4.
Albanell, E., Caja, G., Plaixats, J., 1991. Characteristics of Spanish
carob pods and nutritive value of carob kibbles. Cahiers Options
Mediterranean 16, 135–136.
Barracosa, P., Osorio, J., Cravador, A., 2007. Evaluation of fruit and
seed diversity and characterization of carob (Ceratonia siliqua L)
cultivars in Algarve region. Scientia Horticulturae 114, 250–257.
Battle, I., Tous, J., 1997. Carob tree. Ceratonia siliqua L. promoting
the conservation and use of underutilized and neglected crops. 17.
Institute of Plant Genetics and Crop Plant Research. Gatersleben/
International Plant Genetic Resources Institute, Rome.
Bengoechea, C., Romero, A., Villanueva, A., Moreno, G., Alaiz, M.,
´n, F., Guerrero, A., Puppo, M.C., 2008. Composition and
structure of carob (Ceratonia siliqua L) germ proteins. Food
Chemistry 107, 675–683.
Biner, B., Gubbuk, H., Karhan, M., Aksu, M., Pekmezci, M., 2007.
Sugar profiles of the pods of cultivated and wild types of carobbean
(Ceratonia siliqua L.) in Turkey. Food Chemistry 100, 1453–1455.
Browne, C.A., Zerban, F.W., 1955. Physical and Chemical Methods of
Sugar Analysis, third ed. John Wiley and Sons, pp. 497–512.
Calixto, F.S., Canellas, J., 1982. Components of nutritional interest in
carob pods Ceratonia siliqua. Journal of the Science of Food and
Agriculture 33, 1319–1323.
Girolamo, R., Laura, D., 2002. Evaluation and preservation of genetic
resources of carob (Ceratonia siliqua L.) in southern of Italy for
pharmaceutical use. Breeding Research on Aromatic and Medicinal
Plants 9, 367–372.
von Haselberg, C., 1988. A contribution to the classification and
characterisation of female and male varieties of Ceratonia siliqua L.
In: Fito, P., Mulet, A. (Eds.), Proceedings of the II International
Carob Symposium, Valencia, Spain, pp. 137–151.
Hoichman, D., Gromova., L.I., Sela, J., 2007. Synergistic gel forma-
tion in aqueous solutions of guar–gellan composition. Pharmaceu-
tical Chemistry Journal 41, 42–45.
Kumazawa, S., Taniguchi, M., Suzuki, Y., Shimura, M., Kwon, M.S.,
Nakayama, T., 2002. Antioxidant activity of polyphenols in carob
pods. Journal of Agricultural and Food Chemistry 50, 373–377.
Lafuente, B., 1961. Azticares de la algarroba I. La fermentaci6n
selectiva de las hexosas en la obtenci6n de sacarosa. Revista de
Agricultura y Technologia de Alimentos 1, 1–7.
4 H. El Batal et al.
Please cite this article in press as: El Batal, H. et al., Sugar composition and yield of syrup production from the pulp of Moroccan
carob pods (Ceratonia siliqua L.). Arabian Journal of Chemistry (2011), doi:10.1016/j.arabjc.2011.10.012
Makris, D.P., Kefalas, P., 2004. Carob pods (Ceratonia siliqua L.) as a
source of polyphenolic antioxidants. Food Technology and Bio-
technology 42, 105–108.
Manso, T., Nunes, C., Raposo, S., Lima-Costa, M.E., 2010. Carob
pulp as raw material for production of the biocontrol agent P.
agglomerans PBC-1. Journal of Industrial Microbiology & Bio-
technology, 1367–5435.
Naghmouchi, S., Khouja, M.L., Romero, A., Tous, J., Boussaid, M.,
2009. Tunisian carob (Ceratonia siliqua L.) populations: morpho-
logical variability of pods and kernel. Scientia Horticulturae 121,
Petit, M.D., Pinilla, J.M., 1995. Production and purification of a sugar
pods syrup from carob. Lebensmittel-Wissenschaft und-Technolo-
gie 28, 145–152.
Sidina, M.M., El Hansali, M., Wahid, N., Ouatmane, A., Boulli, A.,
Haddioui, A., 2009. Fruit and seed diversity of domesticated carob
(Ceratonia siliqua L.) in Morocco. Scientia Horticulturae 123,
Tous, J., Batlle, I., Romero, A., 1995. Prospeccio
´n de variedades de
algarrobo en Andalucı
´a. Informacio
´cnica Econo
´mica Agraria
3, 164–174.
Turhan, I., Bialka, K.L., Demirci, A., Karhan, M., 2010. Ethanol
production from carob extract by using Saccharomyces cerevisiae.
Bioresource Technology 101, 5290–5296.
Wahid, W., Gonza
´lez-Martınez, S.C., El Hadrami, I., Boulli, A., 2006.
Variation of morphological traits in natural populations of
maritime pine (Pinus pinaster Ait) in Morocco. Annals of Forest
Science 63, 83–92.
Yousif, A.K., Alghzawi, H.M., 2000. Processing and characterization
of carob powder. Food Chemistry 69, 283–287.
Sugar composition and yield of syrup production from the pulp of Moroccan carob pods (Ceratonia siliqua L.) 5
Please cite this article in press as: El Batal, H. et al., Sugar composition and yield of syrup production from the pulp of Moroccan
carob pods (Ceratonia siliqua L.). Arabian Journal of Chemistry (2011), doi:10.1016/j.arabjc.2011.10.012
... Several studies concerning the soluble solid extraction from the carob [1, 2, 7-9, 11, 13-25] are available. However, studies describing the interactions between sugar extraction factors are rare [8,9,16,18,19,23]. This study aimed to investigate the optimum extraction conditions for obtaining high yield and pure sugar extracts from the carob pods with minimum impurities such as phenolic contents. ...
... 5-50. 1 g/100 g DM in Morocco and 46.95 g/100 g DM in Spain also, reducing sugar levels in Morocco and Spain were 11.3-14.6 g/100 g and 12.75 g/100 g DM, respectively [19,27,28]. It was reported that the main sugar profiles of the carob pods grown in the Mediterranean and Aegean basin of Turkey had been determined and the pods of cultivated varieties had a higher (p<0.05) ...
... Increasing the amount of solvent may increase the extraction yield, but concentrating on the over-diluted solution may result in uneconomically low-quality products [1]. Carob extract yields have been reported to be 28-39 g/100 g pulp in Morocco [19], and 54.24 g/100 g pulp in Spain [8]. ...
Full-text available
The carob (Ceratonia siliqua L.), a plant that grows widely in the Mediterranean climate, has a very dry and hard fruit that contains substantial amounts of sugar and phenolic compounds. This study aimed to determine the optimum extraction conditions for obtaining pure sugar extract with the least undesired compounds from the dried carob pod, and exclude the phenolic compounds that contribute to bitterness, astringency, turbidity, and color. In this study, the effect of extraction parameters as the fruit particle size (X1: 0.30–3.67 mm or 50.0–5.0 mesh), water: fruit ratio (liquid/solid ratio, X2: 2.3–5.7 ml g-1), extraction temperature (X3: 15–75 °C), and extraction time (X4: 44–196 min) on sugar composition and phenolic contents of carob extract was evaluated and an experimental design was developed using response surface methodology central composite design. When the effects of the interactions between the factors on the sugar concentration of carob extract were examined; the most significant effect (p<0.01) was shown by the extraction temperature and extraction time interaction (X3 × X4). The interactions of particle size and water: fruit ratio (X1 × X2) and interactions of particle size and extraction time (X1 × X4) were statistically significant (p<0.05). The optimum extraction conditions were determined as X1: 4.0 mm (5.0 mesh), X2: 4 ml g–1, X3: 20 °C, and X4: 200 minutes. In this study, the individual effects of the factors (X1, X2, X3, and X4) on the extraction were examined and the interaction effects of factors on responses to the extract. Consequently, regression equations showed the relations between the responses and the tested factors.
... Concerning the extracted polyphenols in this last stage, a mean value of 1.7 ± 0.5 mg GAE per mL of syrup was registered. Finally, after the separation from the solid part, the juice was concentrated by evaporation at a high temperature (>100 • C) until the commercial level of around 66 • Brix, to avoid reaching the super-saturation point [19]. ...
... Processes 2022, 10, x FOR PEER REVIEW 5 of 11 was concentrated by evaporation at a high temperature (>100 °C) until the commercial level of around 66 °Brix, to avoid reaching the super-saturation point [19]. As described above, the traditional method to process the carob syrup was very timeconsuming and potentially could provoke the degradation of the phenol chemical structure due to the high temperature used. ...
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Carob syrup is one of the most important carob products, which can have applications in pastry and confectionery, as a fruit preservative, but also in the pharmaceutical field because of the antimicrobial activity due to its polyphenol content. Carob syrup is traditionally made through a very time-consuming process, involving solid–liquid extraction in boiling water and concentration at a high temperature (>100 °C), which potentially causes the degradation of the active compounds (i.e., procyanidins or flavonol glycosides). Therefore, in this work, an alternative and less drastic method based on ultrasound technology was proposed to produce carob syrup. Processing conditions (i.e., time, temperature, and liquid–solid ratio) influencing the extraction of total soluble solids (TSS) and total phenolic compounds (TPC) were optimized using a central composite design coupled to response surface methodology. Reliable mathematical models allowed us to predict the highest TSS (24 ± 2 °Brix) and TPC (1.7 ± 0.5 mg/mL) values that could be obtained at 15 min, 35 °C, and 2 mL/g. Finally, a different HPLC-DAD phenolic pattern was determined between syrups produced by traditional and ultrasound methods; epicatechin, 4-hydroxycoumaric acid, and ferulic acid were more concentrated in the former, while procyanidin B2, myricitrin, and quercitrin were prevalent in the latter one.
... The global production of the Locust Bean is relatively around 315,000 tons/year, with yields varying greatly based on the climate, genotype of the plant and the cultivation Fig. 1 The major parts of Locust Bean tree: the pulp" mature pods", and seeds (Image taken from Tyre, Lebanon 2022) style. The biggest grower of Locust Bean is Spain, followed by Italy, Portugal, Morocco, Greece, Cyprus, Turkey, Algeria, and a few other countries (El Batal et al. 2016). ...
The Locust Bean (Ceratonia siliqua L.) is an ancient Mediterranean fruit that is used to make locust bean gum from seeds, which is a popular ingredient in many foods today. Locust Bean fruit and Gum are rich in bioactive compounds that can be helpful in the treatment of conditions involving the digestive system, as well as cancer, hyperlipidemia, and diabetes. The locust bean gum is a polysaccharide extracted from the endosperm of the locust bean seed through different thermomechanical or chemical processes. It is an approved food additive with the European number E410 and a number of different food uses. It is a galactomannan and it is frequently used in dairy products for its water-binding and thickening properties to improve their rheological properties. This review aims to study the functional, and nutritional characteristics of Locust Bean Gum, the extraction of Locust Bean Gum, as well as its applications in the food sector and its impacts on dairy product processing.
... Moreover, the pulp is a rich source of polyphenolic compounds that illustrate a wide range of in vitro biological activities including antioxidant, antibacterial, anti-cancer and anti-inflammatory actions (Stavrou et al., 2018;Liu et al., 2019;Sun et al., 2019). Despite its nutritional, health and economic importance, carob pulp remains, so far, underexploited and it is generally intended for animal nutrition or is used for production of traditional specialities such as molasses or syrup (El Batal et al., 2016;Ben Othmen et al., 2021). There are few data about the phytochemical profiles of carob pulp and results are quite different, possibly due to the different carob cultivars, origins and storage conditions, and also the use of different analytical methods (Papagiannopoulos et al., 2004;Custódio et al., 2007;Roseiro et al., 2013). ...
In the present study, Tunisian carob (Ceratonia siliqua L.) pulp samples harvested from ten different geographic regions (Bizerte, Beja, Ariana, Ben Arous, Jendouba, Siliana, Zeghouan, Nabeul, Sousse, Kairouan) were analyzed for their bioactive phytochemical content and antioxidant activities. Total phenolics (TPC), flavonoids (TFC), condensed tannins (CT) were determined using Folin-Ciocalteau, aluminium trichloride (AlCl3) and vanillin assays, respectively. Significant variations (p < 0.05) in total polyphenols (TPC), flavonoids (TFC) and condensed tannins (CT) contents were observed between the analyzed provenances. The highest levels of TPC (23.11 mg GAE/g DR) and TFC (10.58 mg CE/g DR) were detected in Kairouan site, whereas Beja sample exhibited the higher amount of CT (3.75 mg CE/g DR). Reversed phase RP-HPLC analysis revealed that gallic acid (501.26–1628.46 mg/kg), ellagic acid (398.85–940.53 mg/kg) and isoquercetin (264.79–817.61 mg/kg) were the major phenolics in all studied extracts, with concentrations varying significantly according to the geographical origin. Using total antioxidant capacity, DPPH, ABTS and FRAP assays, carob pulp extracts were found to have substantial antioxidant activities, which were correlated to their phenolic contents. Multivariate statistical analysis (PCA) performed on phenolic profiles and antioxidant activities revealed three distinctive groups of samples. It was concluded that Ceratonia siliqua L.. pulp from lower semi-arid and upper arid regions of Tunisia presented appreciable amount of phenolic compounds and high antioxidant capacities. This resource deserves further attention mainly for its high potential in culinar, pharmaceutical and cosmetic utilisations.
... Carob fruit is widely used in the food industry as functional foods [6]. The carob flour can be used in the preparation of gluten-free macaron [7], roasted and used as a cocoa substitute [8], or even soaked in water to make beverages and syrup [9], and thanks to the high viscosity and gelling effect of the CBG; it is used as a food additive (stabilizer and thickener) [10]. ...
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Carob fruit samples (Ceratonia siliqua L.) harvested from eight different regions of Morocco (Tafraout, Tiznit, Imintanoute, Ourika, El Ksiba, Imouzzer Kandar, Al Hoceima, and Chefchaouen) were subjected to qualitative analysis employing Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (FTIR-ATR) in the mid-infrared region combined with Principal Component Analysis (ACP). FTIRATR disclosed the major functional groups and their modes of vibration in the pulp, seed, and endosperm of each region. The peaks of the sugar region are stronger in pulp samples. However, peaks of protein region are stronger in seed and endosperm. Pulp and endosperm samples were discriminated by the ACP, while seed intersected with them. Finally, a geographical classification was carried out for each part of the carob fruit.
... In addition, the increasing commercial value of carob has triggered more attention to this multipurpose tree. Carobs have been broadly grown for their fruits (commonly known as pods), which are nowadays highly used in the agro-food industry, in which the pulp represents the major part and is mainly used to produce syrups and powder (Bengoechea et al. 2008;El Batal et al. 2011;Papaefstathiou et al. 2018;Brassesco et al. 2021). The seeds are the most valuable components of carob pods, accounting for 10 to 20% of their weight (Sidina et al. 2009;Boublenza et al. 2019). ...
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Background The carob tree ( Ceratonia siliqua L.) is one of the most iconic tree species of the Mediterranean region, with valuable economic, ecological and cultural value. Carob has been exploited around the Mediterranean region since antiquity and has been regarded as an important component of natural habitats and traditional agroecosystems. Several studies have focused on its morphological, biochemical, and genetic diversity. However, less is known about the intraspecific variation of seed traits. In this regard, and as an overall objective, we intend to evaluate the amplitude and the expression of intraspecific variations of carob seed traits at different ecological scales ranging from individual trees to different geographical landscapes. In addition, we investigated how the climate along the study area affects the extent of carob seed variability. Using image analysis techniques, we measured seven traits related to the size and the shape of 1740 seeds collected from 18 populations of spontaneous C. siliqua distributed along a latitudinal transect in Morocco under different bioclimatic conditions. Results The morphometric analysis of carob seed showed the effectiveness of adopted approach to highlight the amount and the amplitude of intraspecific variation according to geographic and climatic factors. Seed trait analysis revealed high intraspecific variability, explained by differences between and among carob populations and geographic zones. Seed area, perimeter, length, and width showed the largest variability between geographic zones. However, circularity, aspect ratio, and seed roundness showed higher variability at the tree level. Finally, our results show that seed traits vary depending on altitude and climate condition. Conclusions Revealing the amount and the structure of intraspecific traits variability of carob seed provides interesting insights to understand the mechanisms underlying trees adaptation to various environmental and ecological conditions. Therefore, intraspecific variation of seed traits should be integrated into trait-based functional ecology to assess plant species responses to environmental changes.
... It is true that carob powder contains glucose, but not enough to induce inhibition. According to El Batal et al. (2016), sucrose, fructose, and glucose are the main sugar forms constituting the carob pods. On average, their contents are estimated, respectively, at 30%, 10%, and 4% for wild varieties (Biner et al. 2007). ...
In developing countries, most of the daily produced household wastes are buried in landfill sites without any prior treatment. One of the many problems associated with these landfills is the formation of leachate. Because of its complexity and unpredictable composition, leachate has always constituted a challenging task for effluent managers. Despite the countless techniques that have been developed since then, leachate treatment still raises big concerns about the efficiency and sustainability of a suitable strategy. Accordingly, this study is carried out aiming at the optimization of leachate treatment through biostimulation using carob powder as a co-substrate. The added amount of biostimulant corresponds approximately to the addition of 3, 1, and 0.4 g/L of sucrose, fructose, and glucose, respectively. The adopted experimental system is based on the anaerobic process using an up-flow anaerobic sludge blanket (UASB) reactor, which was operated at HRT and OLR of 24 h and 26.1 kg COD/m3 d, respectively. For carob particle size larger than 2 mm, only a small amount of biogas was produced and the COD removal efficiency was lower than 77%, indicating that the poor quality of the effluent persists. However, 97% of COD was efficiently removed and a volume of 2.06 L/Lleachate of biogas was produced using a carob particle size of 0.250 mm. The obtained results showed also that the amount of produced biogas increases as the carob sugar content increases. Literally, a 1% fraction of total sugar content resulted in an increase of 17.9 mL/Lleahate of the produced biogas. Finally, the use of 10 g/L of carob amendment improved COD removal and exhibited less influence on syntrophs and methanogens since a large amount of biogas was generated.
Crystallization is one of the most important steps in the technological flow of commodity sugar. By its nature, it develops in a fairly wide temperature range, conditions of varying concentration of the solution, its peptization and other mass-exchange process of formation and growth of sugar crystals in a sugar solution by diffusion transfer in it sucrose molecules. To this it is necessary to add such complicating physical and mathematical formalization phenomena, affecting crystallization, such as the shape of the crystal, purity, viscous properties and surface tension of the solution, the presence of non-sugars, etc. Therefore, among the factors that determine the whole process, the factors usually take place, keeping among them only priority and most important from the point of view of the study. The article, unlike known analogues, provides justification and quantitative analysis of the kinetics of the sucrose crystallization process, taking into account the features of the crystal shape and diffusion properties of the solution. From the point of view of classical diffusion theory, the phenomenon of crystallization is interpreted as molecular with infinite rate of perilation from the source of diffusion transfer in the solution of sucrose molecules, so that the concentration in the sugar-containing liquid system is also supposed to change instantly at each point. However, since in the real world this effect is not observed, in order to resolve this contradiction, introduce the concepts of the indignant and unperturbed, separated by the diffusion front of the concentration of the regions of these phase states. Using the kinematic characteristics of the front, determine the time of the crystallization process in general in both phases. This allows us to calculate the processing period of the solution with greater accuracy than the results obtained on the basis of classical theory.
The drying process is a fundamental operation in the industry that demands much energy and time, this method is used in order to increase the shelf life of the products as well as the mass and volume during the storage and the transportation. The moisture content permits the deterioration of quality through the microorganisms and the enzymatic reactions. This work aims to study the carob seeds (Ceratonia Siliqua L.) solar drying using a convective solar dryer in order to study and understand the drying kinetics and obtain the characteristic drying curve in different temperatures (50, 60, 70 and 80 °C) and drying air velocities (0.18 and 0.10 m s−1). It was concluded that the increase in the drying temperature reduces the drying time. Six mathematical models were used to appropriately interpret the experimental data; it was found that Verna was the perfect model to represent the drying curves of the carob seeds. The variation of the diffusivity coefficient was found in a range of 1.1968 10−9–4.1482 10−9 m2 s−1, an increase in this coefficient is noticed with the increase in the drying temperature. In order to evaluate the activation energy of the studied product, the Arrhenius relation was called and the average activation energy was found to be 41.46 kJ mol−1. An energy analysis has conducted in order to evaluate the performances of the studied solar dryer. The energy efficiency of the convective dryer was varied in a range of 2.6–4.2%.
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Nineteen Tunisian carob populations from different sites were studied to assess their genetic variation based on pods and kernels measures. The mean of the main descriptive morphological values of pods were weight (16.39g), length (168.9mm), width (20.5mm), lateral thickness (8.3mm), central thickness (5.8mm), number of viable kernels (12.26), number of aborted kernels (1.38), kernels weight (0.2g), kernel length (9.1mm), kernel width (6.9mm), kernel thickness (4.1mm) and kernel yield (17.2%). Most of the parameters measured showed significant differences (P
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The carob tree (Ceratonia siliqua L.) is an important economic resource for Morocco's rural populations. This species is used in reforestation actions and its cultivation in modern orchards is being undertaken to valorize marginal lands and substitute for drought sensitive species. However, little data is available on its intra-specific variability and its adaptability. Morphological characters of pods and seeds from 13 ecoregions of private-domesticated carob were used to assess phenotypic variation of this species. These stands extend from south-west to north-east and cover a wide range of Morocco's ecoregions. Pods length, width, thickness, seeds number, pulp weight, seeds yield and seeds length, width, thickness and weight were measured for 390 trees (30 trees per ecoregion). Statistically significant differences were found between ecoregions for all characters which were examined, what indicates a high phenotypic diversity. Principal component analysis (PCA) and hierarchical cluster of all ecoregions lead to identify two major and opposite groups (the northern ecoregions; and the central and south-western ecoregions). Ecoregions of the north of Morocco exhibited the largest and the thickest pods with the highest pulp weight while other ecoregions have relatively short pods but largest proportion of seed yield. Similarly, the northern ecoregions are characterized by the heaviest seeds. A correlation matrix between morphological characters, geographic parameters and precipitation exhibits a positive and a negative correlation of pods thickness and pulp weight with the latitude and the altitude, respectively. Seed yield and weight are negatively and positively correlated to pod width, pod thickness and pulp weight, respectively. In addition, seed weight is positively correlated with the latitude. The geographic pattern of the carob tree and its variability are discussed in this paper.
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This study was focused on the analysis of the chemical composition of defatted carob germ flour and the protein isolate. The amino acid composition and the nature of the subunits that compose carob germ proteins were also studied. Isolate was obtained by alkaline extraction followed by isoelectric precipitation of proteins. Results showed that an isolate of 96.5% of protein content was obtained. A high amount of amino acids like glutamic acid, aspartic acid and arginine was detected. Carob proteins were found to be composed by aggregates formed by a 131 and 70kDa subunits linked by non-covalent bonds, and other peptides strongly bounded by disulfide interactions. Both, aggregates and subunits were formed mainly by 100 and 48kDa monomers linked by disulfide bonds. A considerable content of high molecular mass peptides (HMWP) strongly bounded were also found. Proteins became partially denatured and thermally stabilized at acid pH (pH 2). These results could be useful in the study of different functional properties of carob germ proteins, and the application of these proteins as nutritional ingredients in formulated food.
The carob tree (Ceratonia siliqua L.) is widely used in the Mediterranean countries for ornamental and industrial purposes. The carob is used in the pharmaceutical industries for therapeutical treatment and in the liquor industry. The area devoted to carob cultivation in Italy is now restricted mostly to marginal areas. The aim of this study was to contribute to the knowledge of the carob genetic resources at a time of increasing risk of its genetic erosion with an investigation into the morphological variability of in situ collected plants in different regions of Southern Italy. The morphology (length width and thickness, apical, basal and middle) of seeds and fruits was determined, using a descriptor list. The results showed considerable variation for most of the examined characters.
Carob pods contain about 200–500 g/kg of total sugars, a higher content of sugar than is present in beet or cane, which is below 200 g/kg. In the present paper a sugar syrup (concentrate solution of several sugars) from carob pods has been obtained with a concentration of sugars near 580 g/kg, 62° Brix and 93% of purity. Extraction and purification techniques were performed. From the results of the extraction researches it can be concluded that a 10 column system connected in series is the most advantageous for efficiency and automation of the sugar extraction reaching a yield of at least 90%. In the purification technique a discontinuous treatment followed by purification in several types of columns connected in series have been studied in order to obtain a transparent and colourless extract.
Determination of the tannins, pectins, hemicellulose, cellulose, nitrogen, mineral elements, total and reducing sugars and fat contents was carried out on carob pods from Mallorca, Spain. The results are compared with data from the literature. A survey of papers on the composition and practical applications of carob pods is included.
The aim of the study was to determine the main sugar profiles of the pods, without the seeds, of cultivated and wild types of the carob bean grown in the Mediterranean and Aegean basin of Turkey. The most abundant sugar in the pods was sucrose with smaller amounts of glucose and fructose. The pods of cultivated varieties had a higher (p < 0.05) total sugar concentration of 531 ± 93 g/kg dry weight than the wild type selections which had 437 ± 77 g/kg. However, this difference was due to the greater concentration of sucrose in the cultivated varieties which did not differ from the wild types in their concentrations of fructose or glucose. The ratios of individual sugars to total sugars in the pods were similar in both varieties. There is a need to identify extreme wild types, including high seeds and low pod, and cultivated types, containing low seeds and high pod, rich in sugar for an exhaustive picture of the sugar profiles of the varieties.