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Evaluation of the Physicochemical and Sensory Characteristics of Different Fig Cultivars for the Fresh Fruit Market

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Physicochemical and sensory properties of nine fig cultivars: ‘San Antonio’ (SA), ‘Blanca Bétera’ (BB), ‘Brown Turkey’ (BT), ‘Tres Voltas L’Any’ (TV), ‘Banane’ (BN), ‘Cuello Dama Blanco’ (CDB), ‘Cuello Dama Negro’ (CDN), ‘Colar Elche’ (CE), and ‘De Rey’ (DR), were compared at three different ripening stages. Weight, size, titratable acidity, pH, skin and flesh colours, firmness, maturation index (MI), and volatile compounds were determined in samples from two consecutive seasons, in addition to both descriptive and hedonic sensory analysis. The mechanical behaviour of figs determined by firmness analysis and colour changes in both skin and flesh was the most important trait for the discrimination of ripening stages. Notable differences among cultivars were found in most of the parameters studied, in particular the inter-cultivar differences highlighted for MI, pH, acidity, and skin colour analyses, followed by volatile compounds. Principal component analysis (PCA) indicated that MI, pH, colour parameters of flesh (h and L*), and terpenes were the best physicochemical indices to determine overall acceptability which is highly correlated with the sensory attributes flesh colour and fruit flavour. The results suggested that CDN and SA showed huge consumer acceptability among the fig cultivars studied.
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Foods 2020, 9, 619; doi:10.3390/foods9050619 www.mdpi.com/journal/foods
Article
Evaluation of the Physicochemical and Sensory
Characteristics of Different Fig Cultivars for
the Fresh Fruit Market
Cristina Pereira
1,2
, Alberto Martín
1,2,
*, Margarita López-Corrales
3
, María de Guía Córdoba
1,2
,
Ana Isabel Galván
3
and Manuel Joaquín Serradilla
4
1
Food Science and Nutrition, School of Agricultural Engineering, University of Extremadura, Avda. Adolfo
Suárez s/n, 06071 Badajoz, Spain; crtpereiraj@gmail.com (C.P.); mdeguia@unex.es (M.d.G.C.)
2
University Research Institute of Agro-Food Resources (INURA), Avda. de la Investigación s/n, Campus
Universitario, 06006 Badajoz, Spain
3
Department of Horticulture, Research Centre Finca La Orden-Valdesequera (CICYTEX), Junta de
Extremadura, Autovía Madrid-Lisboa s/n, 06187 Badajoz, Spain; margarita.lopez@juntaex.es (M.L.-C.);
anabelgalvanromero@gmail.com (A.I.G.)
4
Department of Plant Sciences, Agrifood Technology Institute of Extremadura (INTAEX-CICYTEX), Junta de
Extremadura, Avda. Adolfo Suárez s/n, 06007 Badajoz, Spain; manuel.serradilla@juntaex.es
* Correspondence: amartin@unex.es; Tel.: +34 -924-289-300 (ext. 86255)
Received: 6 April 2020; Accepted: 9 May 2020; Published: 12 May 2020
Abstract: Physicochemical and sensory properties of nine fig cultivars: ‘San Antonio’ (SA), ‘Blanca
Bétera’ (BB), ‘Brown Turkey’ (BT), ‘Tres Voltas L’Any’ (TV), ‘Banane’ (BN), ‘Cuello Dama Blanco’
(CDB), ‘Cuello Dama Negro’ (CDN), ‘Colar Elche’ (CE), and ‘De Rey’ (DR), were compared at three
different ripening stages. Weight, size, titratable acidity, pH, skin and flesh colours, firmness,
maturation index (MI), and volatile compounds were determined in samples from two consecutive
seasons, in addition to both descriptive and hedonic sensory analysis. The mechanical behaviour of
figs determined by firmness analysis and colour changes in both skin and flesh was the most
important trait for the discrimination of ripening stages. Notable differences among cultivars were
found in most of the parameters studied, in particular the inter-cultivar differences highlighted for
MI, pH, acidity, and skin colour analyses, followed by volatile compounds. Principal component
analysis (PCA) indicated that MI, pH, colour parameters of flesh (h and L*), and terpenes were the
best physicochemical indices to determine overall acceptability which is highly correlated with the
sensory attributes flesh colour and fruit flavour. The results suggested that CDN and SA showed
huge consumer acceptability among the fig cultivars studied.
Keywords: Ficus carica L.; sensory properties; volatile compounds; colour; firmness
1. Introduction
The fig (Ficus carica L.) constitutes a spice that is widely grown in the Mediterranean area,
where the fig tree population has been present since its domestication [1]. In this area, both fresh and
dried figs are an important part of the diet, being especially rich in nutrients such as sugar, fibre,
proteins, and minerals, but also in organic acids and polyphenols. Spain is the major producer of figs
in Europe, with approximately 36,380 tonnes, i.e., 38% of European production and 3% of world
production [2]. Although most commercial production is of dried fruit, figs are also widely
consumed as fresh fruit.
Fresh fruit quality is determined by nutritional and bioactive composition, but also by other
parameters related to the sensory characteristics, including firmness, visual appearance, taste, and
aroma [3]. Firmness is one of the primary attributes determining consumer acceptance, flesh
Foods 2020, 9, 619 2 of 16
firmness being the parameter used to determine the harvest time as well as the maturity grade
during postharvest of perishable fruit such as fig [4]. Sugars, acids, and phenolic compounds
contribute to the taste and colour of figs, but also to the characteristic of flavour, which is dependent
mainly on the proper balance of the volatile chemical constituents [5,6]. On the other hand, the
aromatic compound profile of each variety is considered to be unique and has a great influence on
organoleptic characteristics and therefore on consumer acceptance [3,5]. Recently, the use of
techniques as solid-phase microextraction of headspace (HS-SPME) with gas chromatography
analysis with a mass detector (GC-MS) has made it possible to identify and quantify individually
this complex mixture of aromatic compounds, which mainly includes compounds such as alcohols,
aldehydes, ketones, esters and terpenoids. Additionally, this complex mixture depends on several
factors such as soil, climate, genotype, ripeness, and technological aspects [7]. Compounds such as
ethyl acetate, hexanal, β-caryophyllene, limonene, (E)-2-hexenal, and octanal have been attributed
primarily to the aroma of fresh figs [8–10]. In addition, compounds such as furfural, benzaldehyde,
phenol, among others, have also shown a remarkable influence on the aroma of fresh fig [11,12]. The
volatile composition in fresh figs varies during the ripening process and with it the perception of
their sensory characteristics [5,11]. Thus, in fruit such as kiwifruit, a considerable increase in the
ester content and a decrease in the concentration of aldehydes throughout ripening has been
described [13]. However, in the case of figs, the concentration of both compounds has also been
clearly influenced by genotype [1].
The majority of studies related to the characterisation of quality parameters of fresh fig cultivars
approach specific quality aspects such as physicochemical properties [14–16], firmness, or aroma
compounds [5,10,11]. Regarding the volatile aroma profile of figs, some studies have focused on the
analysis of aromatic compounds from leaves, spirits, extracts and others [5,8–11]. So far, however,
only a few studies showed an overall view of the relation among physicochemical parameters and
sensory attributes taking into account different ripening stages. Thus, Crisosto et al. [17] reported the
influence of two ripening stages on different physicochemical traits as well as other parameters such
as the total antioxidant capacity of four fig cultivars currently grown in California, highlighting the
great impact of total soluble solids content on consumer acceptance. King et al. [18] also
characterised the sensory properties of 12 California-grown fresh fig cultivars from six different
sources, finding significant correlations between sensory and physicochemical data. These authors
highlighted the importance of selecting cultivars with strong flavours that remain firm as they
mature.
To our knowledge, a comprehensive and interannual study of both physicochemical and
sensory quality characteristics in several commercial cultivars of fresh fig has never been carried out.
In this research, we established the relation among these physicochemical and sensory parameters
and an overview of quality traits of the fig cultivars studied for fresh fruit market, taking into
account the changes associated with the different commercial ripening stages.
2. Materials and Methods
2.1. Plant Material and Experimental Design
The nine fig tree cultivars studied for fresh consumption in the order of ripening (early, middle
or late) were ‘San Antonio’(SA), ‘Blanca Bétera’ (BB), ‘Brown Turkey’(BT), ‘Tres Voltas L’Any’(TV)
as early cultivars, ‘Banane’(BN) as mid cultivar, ‘Cuello Dama Blanco’ (CDB), ‘Cuello Dama
Negro’(CDN), ‘Colar Elche’(CE), and ‘De Rey’ (DR) as late cultivars. Studies of morphological and
molecular characterisation conducted in Spanish germplasm fig indicate that ‘Cuello Dama Blanco’
and ‘Colar Elche’ are the same varieties as ‘Kadota’ and ‘Mission’, respectively [19–21]. All cultivars
were selected among those available in the national germplasm bank of the fig tree is located in the
research centre “Finca La Orden-CICYTEX” at an altitude of 223 m above sea level (latitude
38°8519 N, longitude 6°6828 W, Guadajira, Badajoz, Spain) based on parameters of fruit quality.
Figs were harvested manually from July to October. With respect to the experimental design, fig
samples were hand-collected when they were fully mature and were harvested during two
Foods 2020, 9, 619 3 of 16
consecutive seasons from an experimental orchard established in 2007 and previously described in
our previous work [22].
For the maturation study, three different ripening stages of each cultivar were selected
according to their skin colour and firmness as per expert harvester criteria. Stage 1 corresponded to
the greener fruit, whereas Stage 3 corresponded to mature fruit. For each physicochemical
determination, three replicates of 10 fruit for each ripening stage and cultivar were established per
year. All analyses were conducted using fresh fruit, but for analysis of volatile aroma profile, the
samples were weighed in vials and stored at 80 °C for later analysis.
2.2. Weight and Size
Both parameters were determined using an AE-166 balance (Mettler, Madrid, Spain) for weight
(g) and a DL-10 digital micrometre (Mitutoyo, Kawasaki, Japan) for size (mm).
2.3. Total Soluble Solids (TSS), Titratable Acidity (TA), pH, and Maturation Index (MI)
A model RM40 Mettler Toledo digital refractometer at 20 °C was used to measure total soluble
solids (TSS) in °Brix. On the other hand, 5 g aliquots of fig homogenate diluted to 50 mL with
deionised water from a Milli-Q water purification system (Millipore, Bedford, MA, USA) were used
to determine titratable acidity and pH, using a T50 Compact Stirrer for automatic titration (Mettler
Toledo, Madrid, Spain), titrating up to pH 7.8 with 0.1 mol L1 NaOH and expressing the results in g
citric acid 100 g1 fresh weight (FW).
The maturation index (MI) was calculated as described by Pereira et al. [22].
2.4. Colour
Skin and flesh colour of figs was measured according to Pereira et al. [22]. The parameters
brightness (L*), chroma (C*) and hue angle (h*) were measured using a Konica Minolta CM600
spectrophotometer in accordance with the CIELab system.
2.5. Firmness
A 6% deformation was applied by a 70 mm aluminium plate coupled to a TA.XT2i Texture
Analyser (Stable Micro Systems, Godalming, UK) to measure firmness in N mm1 [22].
2.6. Determination of Volatile Compounds
The volatile profile from each ripening stage and cultivar was analysed by solid-phase
microextraction (SPME) with a 10 mm-long, 75 µm-thick fibre coated with
Carboxen™/polydimethylsiloxane (Supelco, Bellefonte, PA) as described by Serradilla et al. [23].
The volatile compounds were identified and semi-quantified using an Agilent 6890 GC/5973
MS system (Agilent Technologies) using a DB-5 (Agilent Technologies J&W, Santa Clara, CA, USA)
bonded fused silica capillary column, coated with 5% phenyl/95% polydimethylsiloxane (30 m × 0.32
mm inner diameter, 1.05 µm film thickness). For the identification of volatile profile, in addition to
using the NIST/EPA/NIH mass spectrum library (comparison quality > 90%), and Kovats indices,
which were calculated using a mixture of n-alkanes (R-8769, Sigma Chemical Co., St. Louis, MO,
USA) run under the same conditions [24], pure compounds under the same chromatographic
conditions were also used to confirm the identifications.
2.7. Sensory Analysis
For the sensory analysis, only samples from ripening Stages 2 and 3 were used. A trained panel
of 10 panellists, 6 women and 4 men between the ages of 30 and 50 years old, was used to carry out a
descriptive sensory analysis, assessing the parameters previously described in our previous work
[12]. A numbered scale from 1 to 10 points was used. Each panellist evaluated a total of two
defect-free fruit per ripening stage and cultivar immediately after harvest and after reaching a flesh
Foods 2020, 9, 619 4 of 16
temperature of 20 °C under white lighting, airflow, and temperature (20–22 °C) controlled
conditions. Samples were presented to each panellist on plastic plates in random order using a
3-digit code for each sample, assessing the following sensory attributes: external appearance, skin
colour, flesh colour, firmness, sweetness, acid, bitter, juiciness, presence of seeds, and fruit flavour.
One session was conducted per week throughout the harvest period. Additionally, hedonic tests,
using a numbered scale from 1 to 10 points, were performed to evaluate overall acceptability with a
total of 65 untrained consumers, but regular fig consumers, consisting of 35 women and 20 men aged
20 to 50 years old, was tested every 15 days throughout the harvest period.
2.8. Statistical Analysis
SPSS for Windows, 19.0 (SPSS Inc. Chicago, IL, USA) was used to carry out an analysis of
variance (ANOVA) of the mean values of physicochemical parameters, the area of volatile
compounds, and sensory characteristics. Tukey’s honestly significant differences (HSD) test (p
0.05) was applied to separate means. Principal component analysis (PCA) was used to analyse the
relationships among the parameters studied, using ‘ripening stage’ and ‘cultivar’ as classification
variables.
3. Results and Discussion
3.1. Physicochemical Properties
Fig cultivar weights and sizes at the three ripening stages are shown in Figure 1A,B. The mean
weight of the cultivars studied was 46.5 g, with BT and BN showing the highest values for this
parameter. These same cultivars, along with CE and BB, showed a significant weight increase with
the ripening process, mainly between Stage 1 and Stage 2. For BT, mean weight increased from 54.8 g
(Stage 1) to 77.5 g (Stage 3). A similar weight increase associated with maturity stage was also found
for this cultivar by Crisosto et al. [17]. On the contrary, TV presented weights less than 30 g for the
three stages studied. The weight tendency in fig cultivars was also observed for size, with 43.2 mm
as the mean value, although in this case, differences among maturity stages were not found (Figure
1B).
Foods 2020, 9, 619 5 of 16
Figure 1. Physicochemical parameters of the fig cultivars at the three ripening stages studied. Weight
(A); size (B); pH (C); titratable acidity (TA) (D); total soluble solids (TSS) (E); maturation index (MI)
(TSS/TA) (F). SA, San Antonio; BB, Blanca Bétera; BT, Brown Turkey; TV, Tres Voltas L’Any; BN,
Banane; CDB, Cuello Dama Blanco; CDN, Cuello Dama Negro; CE, Colar Elche; DR, De Rey. Tukey
HSD, Tukey’s honestly significant differences; SSB, Statistical significance bar.
The pH values of the fig cultivars studied are given in Figure 1C. The mean pH value was 5.8,
ranging from 5.16 (BB; Stage 1) to 6.39 (SA; Stage 3), which are slightly higher than those described
by other authors [25,26]. There was an increase in the pH values with increasing maturity, which
resulted in a less acid product. This change associated with ripening time was more evident for
cultivars BN, TV, and BB with a decrease of TA of more than 0.6 g citric acid 100 g1 FW from Stage 1
to Stage 3 (Figure 1D). The mean value of this parameter for the cultivars studied was 1.2 g citric acid
100 g1 FW, ranging from 0.72 (Stage 3 of SA) to 2.14 g citric acid 100 g1 FW (Stage 1 of CDN). This
TA ratio is in line with those obtained by Çalişkan and Polat [27] for fig genotypes grown in the
Eastern Mediterranean Region of Turkey as well as some Turkish cultivars. In general, the early SA
cultivar was characterised by exhibiting the highest pH values and the lowest TA values at the most
advanced stages of ripening.
The fig cultivars studied had an average °Brix of 20.4 and MI of 200.6, all of them showing an
evident increase for these parameters during the ripening process of fig fruit, with the highest values
at maturation Stage 3 (Figure 1E,F). The TSS/acid ratio is directly related to fruit taste and in the fig’s
aptitude for the drying process [27]. The differences between Stage 1 and Stage 3 were more than 6
°Brix for late cultivars CDN and CE, whereas the variation for mid cultivars BN and CDB was less
than 3 °Brix. For MI, the more relevant differences between ripening stages were found for early and
mid cultivars SA, BB, and BN, in contrast to late cultivars DR and CDB, which showed no significant
differences. In general, the °Brix values found in our study were in agreement with other reports
[26,28,29], whereas the MI values were slightly higher, mainly due to the low acidity presented in
the studied cultivars.
0
10
20
30
40
50
60
DR CDB BT SA CDN BN CE TV BB
Size (mm)
Cultivars
0
10
20
30
40
50
60
70
80
90
DR CDB BT SA CDN BN CE TV BB
Weigh t (g )
Cultivars
0
50
100
150
200
250
300
350
DR CDB BT SA CDN BN CE TV BB
Maturation index (MI)
Cultivars
Stage 1 Stage 2 Stage 3
0
0.5
1
1.5
2
2.5
DR CDB BT SA CDN BN CE TV BB
TA (g 100g
-1
FW)
Cultivars
0
5
10
15
20
25
30
DR CDB BT SA CDN BN CE TV BB
TSS (ºBrix)
Cultivars
4
4.5
5
5.5
6
6.5
7
DR CDB BT SA CDN BN CE TV BB
pH values
Cultivars
Stage 1 Stage 2 Stage 3
AB
CD
EF
1.2
5.8
20.4
200.6
46.5
43.2
0.05 TukeyHSD
SSB (± 3.14)
0.05 TukeyHSD
SSB (± 1.27)
0.05 Tukey HSD
SSB (± 0.16)
0.05 TukeyHSD
SSB (± 0.24)
0.05 Tukey HSD
SSB (± 1.02)
0.05 Tukey HSD
SSB (± 42.72)
Foods 2020, 9, 619 6 of 16
3.2. Colour and Firmness
The colour parameters of the fig varieties studied are shown in Figure 2. There were evident
differences in the mean values of skin colour parameters between the dark (CDN and CE),
purple/yellow (SA, BT, and DR), and green cultivars (CDB, TV, BN, and BB), but also between
ripening stages. An increase of h* values was observed for CDN and CE at Stage 3, whereas for the
rest of the varieties the decrease of L* values was the more relevant change. Crisosto et al. [17]
described a significant increase of h* values at the higher maturity stage studied for cv. Mission (syn.
CDN and CE). Likewise, differences were also observed in flesh colour parameters among different
cultivars of figs (p > 0.05), mainly related to the coordinates L* and h* (Figure 2B). The cultivars CDB
and SA showed the highest values for both colour parameters mentioned, with L* values of 55.53
and 59.19 and h* values of 73.47 and 71.39, respectively. On the contrary, the lowest values of L* and
h* in fig flesh were found for CDN and BT (lower than 46.39 and 48.06 for L* and 46.28 and 46.91 for
h*, respectively). These results agree with those for some Turkish fig cultivars which showed great
variability among cultivars with mean values of 53.79 for L* and 42.37 for h* [14].
Figure 2. Colour parameters of the fig cultivars at the three ripening stages studied. Skin (A); flesh
(B). L*, Brightness; C*, Chroma and h*, Hue angle.
On the other hand, there were also differences in the flesh colour among the three ripening
stages of the fig cultivars studied. In this case, C* values decreased during the ripening process for
all fig cultivars studied as a consequence of flesh darkening due to the accumulation of
anthocyanins, this change being more evident in the dark-skinned cultivars CDN and BT. A negative
correlation between total anthocyanins in flesh fruit and the chromatic parameter chroma has been
Foods 2020, 9, 619 7 of 16
described for several fruit such as sweet cherry [30]. After the visual appearance, firmness is the
most relevant factor that determines the acceptability of fleshy fruit such as figs [4], firmness being a
relevant component. Firmness values decreased during the maturation of figs, this process being
cultivar-dependent (Figure 3). Initially, the mean fig firmness values were 2.57N mm
1
at Stage 1,
decreasing to 0.75N mm
1
at Stage 3. Our results during the ripening process of fig cultivars were
similar to those obtained by other authors [17,22]. Regarding cultivar differences, the firmness
values of SA and BB were higher than those of most of the cultivars studied, whereas TV presented
firmness values significantly lower than the rest of the cultivars for all ripening stages studied.
Figure 3. Firmness values of the fig cultivars at the three ripening stages studied.
3.3. Volatile Compounds
A total of 68 compounds were identified in the fig cultivars studied using HS/SPME and
GC/MS (Table 1). These volatile compounds were classified as aldehydes (20), hydrocarbons (9),
furans (8), alcohols (4), terpene compounds (4), ketones (3), acids (3), esters (3), pyranone derivates
(2), pyrimidines (1), and ethers (1). Similar findings in fresh figs were described in previous studies
[5,10,12,31,32].
Among the main volatile compounds that define fresh figs’ aroma profile are aldehydes [31].
These compounds represent a mean percentage of 18.25% of the total area, including linear,
branched, and aromatic aldehydes (Table 1). Regarding aromatic aldehydes, benzaldehyde (AL12)
accounted for 7.13% of the total area as mean value for the fig cultivars studied, being the most
abundant aldehyde found. They originate from the shikimic acid pathway and contribute greatly to
the characteristic aroma of fresh figs [33]. The main linear aldehydes identified were (E)-2-hexenal
(AL9), nonanal (AL18), and hexanal (AL8) (2.65%, 2.41%, and 1.76% of the total area, respectively),
which have also been reported to be key to the volatile aroma profile of some fig cultivars [12,31].
These compounds exceeded 5% of the total area for some cultivars studied and are characterised by
exhibiting green leaf notes [34]. Finally, among the branched aldehydes, 2-methyl-2-butenal (AL5)
showed a high percentage in most of the cultivars studied (1.09% of the total area), while the relative
concentration of the other branched aldehydes was less than 1% of the total area.
Foods 2020, 9, 619 8 of 16
Table 1. Volatile compounds in the fresh fig samples studied.
Volatile compounds CD KI ID§ RT AAU| Percentage of area (%)#
Mean SD Min Max
Hydrocarbons H
4
52 3.18
3.20 0.32 15.15
Pentane, 2-methyl- H1 570 A 7.0 2 0.02
0.10 0.00 0.52
Pentane, 3-methyl- H2 585 A 7.7 6 0.05
0.20 0.00 1.01
Hexane¤ H3 600 A 8.9 241 1.84
1.64 0.23 7.29
Cyclopentane, methyl- H4 635 B 10.3 4 0.03 0.13 0.00 0.67
Heptane H5 700 A 14.7 10 0.08
0.18 0.00 0.55
Toluene H6 779 B 18.8 106 0.66
1.32 0.00 5.57
Ethylbenzene H7 864 B 23.6 17 0.10
0.21 0.00 0.86
p-Xylene H8 869 B 23.8 52 0.29
0.64 0.00 2.39
Tetradecane H9 1400 A 39.4 14 0.10 0.27 0.00 1.16
A
lcohols OL
378 2.50
1.18 0.63 5.71
3-Buten-1-ol, 3-methyl- OL1 726 B 16.7 15 0.11 0.13 0.00 0.53
3-Heptanol OL2 894 B 24.7 44 0.40
0.71 0.00 2.66
Branched alcohol OL3 1028 D 29.8 26 0.30 0.49 0.00 1.90
Aromatic alcohol OL4 1080 D 31.7 292 1.69 0.81 0.40 3.40
A
ldehydes
A
L
2407 18.25
10.34
.99 58.98
Propanal AL1
C 5.2 90 0.60
0.42 0.00 1.95
2-Butenal, (E)- AL2 640 B 11.6 5 0.03 0.09 0.00 0.39
Butanal, 3-methyl- AL3 645 A 11.9 6 0.04 0.10 0.00 0.39
Butanal, 2-methyl- AL4 660 A 12.5 83 0.42 0.64 0.00 2.51
2-Butenal, 2-methyl- AL5 745 B 17.5 98 0.94 1.09 0.00 3.59
2-Pentanal, (E)- AL6 750 B 18.0 27 0.24 0.45 0.00 1.89
2-Butenal, 3-methyl- AL7 783 B 19.4 53 0.37 0.22 0.00 0.72
Hexanal AL8 800 A 20.2 221 1.76
1.44 0.22 5.98
2-Hexenal, (E)- AL9 853 A 22.8 305 2.65 2.97 0.50 15.15
Heptanal AL10 902 A 25.1 58 0.28
0.40 0.00 1.72
2,4-Hexadienal (E,E)- AL11 910 B 25.4 1 0.02 0.07 0.00 0.37
2-Heptenal AL12 952 B 27.4 4 0.04
0.06 0.00 0.23
Benzaldehyde AL13 956 A 27.8 985 7.13
6.33 1.45 32.44
Octanal AL14 1004 A 29.1 50 0.35 0.20 0.00 0.76
2,4-Heptadienal AL15 1010 B 29.4 14 0.11 0.24 0.00 1.09
Benzeneacetaldehyde AL16 1051 B 30.7 20 0.14 0.38 0.00 1.89
2-Octenal, (E)- AL17 1062 C 31.1 16 0.14 0.22 0.00 0.91
Nonanal AL18 1106 A 32.6 294 2.41 1.74 0.00 8.22
2-Nonenal AL19
1164 B 34.5 7 0.04
0.07 0.00 0.27
Decanal AL20 1204 A 35.9 70 0.54 0.60 0.00 2.67
Ketones K
4
95 3.24
1.70 0.71 6.09
3-Heptanone K1 889 B 24.3 373 2.52
1.41 0.67 6.09
1,3-Cyclopentanone K2 992 C 28.8 106 0.64
0.57 0 1.89
2-Cyclopenten-1-one, 2-hydroxy-3-methyl- (Corylon) K3 1029 C 30.0 15 0.08 0.10 0 0.34
A
cid
A
C
594 3.12
1.77 0.02 7.28
Acetic acid AC1
8.3 10 0.05
0.12 0 0.51
Hexanoic acid, 2-ethyl- AC2 1123 32.8 520 2.66 1.62 0 6.15
Nonanoic acid AC3 1277 37.3 64 0.41
0.35 0 1.13
Ester ES
3545 26.93
20.31 0.69 65.61
Acetic acid, methyl ester ES1 554 A 6.2 42 0.38 0.30 0.01 1.15
Acetic acid, ethyl ester ES2 628 A 9.6 3496 26.53 20.11 0.67 65.26
Butanoic acid, methyl ester ES3 723 B 16.4 7 0.02 0.10 0 0.52
Furans F
5831 23.05
13.72 1.83 57.33
Furfural F1 830 A 21.9 966 4.24
2.32 0.51 8.21
2-Furanmethanol F2 859 B 23.0 903 4.39
2.06 0.97 8.2
2(3H)-Furanone, 5-methyl- F3 930 B 26.0 336 1.69 0.83 0.1 2.88
Furaneol F4 1058 B 30.8 49 0.30 0.60 0 2.31
Unknown furan 1 F5 1098 D 32.2 156 0.45 0.64 0 2.31
5-(Hydroxymethyl)-2(5H)-furanone F6 1178 B 34.9 65 0.33 0.57 0 2.34
Unknown furan 2 F7 1197 D 35.5 509 2.14 1.34 0 4.8
5-Hydroxymethylfurfural F8 1224 B 36.5 2847 9.52 8.41 0 33.38
Pyranones P
3041 12.65
7.15 0.81 26.64
2H-Pyran, 3,4-dihydro- P1
25.5 313 1.59 0.76 0.4 2.97
3-Hydroxy-2,3-dihydromaltol P2 1140 B 34.2 2727 11.06
6.54 0.36 25.06
M
onoterpenes
T
156 1.17
1.46 0.00
.72
α-Pinene T1 940 B 26.7 9 0.05
0.14 0 0.65
Unknown monoterpene T2 1006 D 29.2 9 0.04 0.11 0 0.39
Limonene T3 1030 A 30.3 38 0.19 0.29 0 1.18
Linalool T4 1098 B 32.6 101 0.89 1.41 0 4.35
M
iscellaneous
Ethyl ether ET1 A 5.3 10 0.07
0.19 0 0.91
Thymine M1 1075 B 31.6 855 5.85 3.28 0.58 11.5
CD: compound code used. KI: Kovats retention index. § ID: reliability of identification: A,
identified by a comparison to standard compounds; B, tentatively identified by the NIST/EPA/NIH
Foods 2020, 9, 619 9 of 16
mass spectrum library (comparison quality >90%) and Kovats retention index; C, tentatively
identified by the NIST/EPA/NIH mass spectrum library (comparison quality >90%); D, tentatively
identified by the NIST/EPA/NIH mass spectrum library (comparison quality <90%). RT: retention
time. |AAU: arbitrary area units. # %: relative abundance. ¤ In bold: volatile compound included in
PCA analysis, according to high relevance in the volatile profile of the fig cultivar studied.
Hexane (H3) was the most abundant hydrocarbon, a chemical class that involved 3.18% of the
total area as mean value for these studied cultivars, including branched and aromatic compounds
(Table 1). In addition, short-chain alkanes have also been reported, although in lower concentration,
to be present in fig fruit [10], described as non-contributors to fruit flavour. On the contrary,
particularly in light and yellow-green cultivars, other relevant compounds in the aroma profile of
figs are alcohols (2.50% of the total area), whether linear, branched, or aromatic. (Table 1) [31].
3-Heptanol (OL2) is associated with fresh green odours and green leaf notes that are typically linked
to fruit such as yellow passionfruit [35].
Furans represented 23.05% as a mean percentage, ranging significantly between 1.83% and
57.33% of the total area, mainly due to the variability found for 5-hydroxymethylfurfural in the
cultivars studied (Table 1). Both 5-Hydroxymethylfurfural and furfural have been associated with
sweet flavour notes and indeed both have been identified among the characteristic aroma
compounds of several other fruit, such as kiwifruit [6]. Additionally, furans and the derivates of
pyranones have been reported to be derived directly from carbohydrates [36]. Pyranones were the
fourth most abundant chemical class in the cultivars studied, representing a mean percentage of
12.65% of the total area. 3-Hydroxy-2,3-dihydromaltol (P1) was characterised by being the dominant
compound within this family with 11.06% of the total area for these studied cultivars, describing its
aromatic note as caramel. Furan and pyranone derivates show an outstandingly low odour
threshold and are also considered to be primary contributors to the volatile profile of dried figs
[11,37].
Regarding ketones (3.24% of the total area), a total of three of these compounds were identified
(Table 1). 3-Heptanone was the ketone detected at highest concentrations in the cultivars studied.
Pino et al. [38] considered this compound as a green fatty aroma note, and it has been described
among the most important aroma-active volatiles of fruit such as choch (Lucuma hypoglauca
Standley).
With respect to acids (3.12% of the total area), acetic acid (AC1), nonanoic acid (AC3), and the
most abundant 2-ethyl hexanoic acid (AC2) were detected (Table 1). This last compound has a
negative effect on the overall aroma of fruit derivates, possessing an unpleasant odour with slightly
putrid notes [39]. 2-Ethylhexanoic acid has been also reported as a regular food packaging material
contaminant [40]. In our study, cultivars showed a mean percentage of 2.66% of the total area for this
acid.
Esters, with 26.93% of the total area, represented the other main group of aromatic compounds
detected in these fruit. These compounds are generated from the esterification of alcohols and
acyl-CoA derivates, highlighting the concentration shown by ethyl acetate (ES2), at 26.53% of the
total area, as the mean value in the cultivars studied (Table 1). This result could suggest that this
volatile compound may be relevant to the aroma profile of these cultivars. This compound was also
described in two Portuguese fig varieties (‘Branca Tradicional’ and ‘Pingo do Mel’), although the
concentration shown by these cultivars was lower than that obtained in this study [31].
Other compounds, which represented around 1% of the total area of volatile compounds of the
cultivars studied, were monoterpenes such as α-pinene (T1), limonene (T3), and linalool (T4) (Table
1), which are among the most frequent groups of aroma compounds identified in figs [5,8,11,33].
In general, remarkable fluctuations were observed in the volatile profiles of the samples studied
according to the values of standard deviations and ranges shown in Table 1. To understand the role
of both factors, cultivar and ripening stage, in this variability, a PCA was performed with the major
volatile compounds (>0.85% of total area). The PCA showed clear differences in the volatile profile
among the cultivars, and a limited influence of the ripening stages selected in this work (Fig. 4 and
5). Thus, the cultivars SA, BT, and BN showed a lower amount of the main volatile compounds
Foods 2020, 9, 619 10 of 16
compared to DR, BB, and CDB. Concretely, the cultivar DR was associated with high concentrations
of the main furans (F1, F2, F3, F7, and F8), pyranones (P1 and P2), and, to a lesser extent, aldehydes
such as benzaldehyde (AL13) and hexanal (AL8). In the case of cultivars BB and CDB, their volatile
profiles are highlighted for the high amount of 2-methyl-2-butenal (AL5), decanal (AL20), linalool
(T4), and hexane (H3) among other compounds (Figures 4 and 5). The differences found in both
physicochemical properties and volatile profiles of the fig cultivars studied may have a relevant
impact on their sensory parameters.
Figure 4. Loading plot (A) and score plot (B) after principal component analysis of the varieties,
ripening stages, and volatile compounds in the plane by two first principal components (PC1 and
PC2). Code letters for volatile compounds are shown in Table 1.
3.4. Sensory Analysis
H3
H6
AL5
AL9
AL18
AL20 ONA1
ONA2
ES2
T4
M1
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
-1 -0.5 0 0.5 1
PC 2 (14.0%)
PC 1 (49.38%)
DR
CDB
BT
SA
CDN
BN
CE
TV
BB
S1 S2
S3
-1.5
-1
-0.5
0
0.5
1
1.5
2
-1 -0.5 0 0.5 1 1.5 2
PC 2 (14.0%)
PC 1 (49.38%)
OL4
AL1
AL8
AL13
AC2
F1
F2F3
F7
F8
P1
P2
-0.3
-0.2
-0.1
0
0.1
0.2
0.6 0.7 0.8 0.9 1
A
B
Foods 2020, 9, 619 11 of 16
ANOVA of sensory descriptors (Table 2) shows significant differences among most of the fig
cultivars studied but not between ripening Stages 2 and 3, with the exception of external appearance
which was better for samples of ripening Stage 2. CDN and CE cultivars obtained the best scores
(higher than 7.00) for the descriptive parameters—external appearance, skin colour, and
texture—whereas BB was scored highest by panellists for sweetness (5.56), although no significant
differences were found for this parameter. The highest scores for fresh colour and fruit flavour
descriptors were found in CDB and SA samples (5.97–6.70 and 5.67–6.25, respectively), both
parameters showing a high degree of correlation with acceptability in the hedonic test. In fact, these
cultivars showed the best scores for the overall acceptability descriptor (6.71 and 6.65). In the case of
SA, the high score for the descriptor fruit flavour was not correlated with the relatively low number
of volatile compounds found for this cultivar (Figures 4 and 5), showing that the flavour is a
complex combination of not only olfactory but also gustatory-tactile and kinaesthetic sensations [41].
On the contrary, BT presented the worst score for acceptability (4.37), which was clearly related to its
lowest scores for skin colour (5.04), fresh colour (4.02), and fruit flavour (4.05). The difference
between these results and those found by other authors for BT can be partially explained by the
better sensory quality of pollinated fruit with respect to the parthenocarpic fruit used for our study
[42].
3.5. Interactions between the Analytical Parameters and Sensory Characteristics
PCA was carried out for the whole set of data to obtain an interpretable overview of the main
information. Samples at ripening Stage 1 were excluded as they were not sensorially analysed.
Figure 5 shows the two-way loadings and score plots, where PC2 and PC3 were plotted against PC1
to show a high percentage of the total variance (48.20%–41.04%). High values for MI, pH, skin C*,
and skin L* were explained by the positive axis of PC1 and were related to SA and, to a lesser extent,
to CDB and BB. These parameters showed a negative correlation with acidity, skin h, and the
sensory descriptors acid taste, skin colour, external appearance, and texture, which were highlighted
in CDN and CE. The second PC was mainly explained by most of the chemical families of the
volatile compounds located in the extreme of the positive axis, relating high values of those to the
cultivar DR. On the contrary, the cultivars with the highest weight and calibre values, BT and BN,
were associated with the negative axis of PC2 and therefore with a poor concentration of volatile
compounds. Variability of the sensory descriptors sweetness and juiciness was mainly explained by
the positive axis of PC3, showing a clear negative correlation with the descriptor bitter taste, high
values being those associated with BB.
Regarding acceptability, high scores in the hedonic test were correlated with MI, pH, flesh h,
and terpenes, in addition to the above-mentioned sensory descriptors (flesh colour and fruit
flavour). Likewise, the association of high acceptability scores with CDB (plots defined by PC1 and
PC2) was again observed, but also with SA (plots defined by PC1 and PC3).
4. Conclusions
In conclusion, the characteristics of the nine fig cultivars included in this study can be explained
on the basis of the physicochemical and sensory properties studied, most of them showing notable
differences among them. This confirms the relevance of characterising fig cultivars for the
assessment of potential consumer acceptability. In agreement with the PCA results, MI, pH, acidity,
and skin colour show the highest variability among the parameters studied in fresh figs, followed by
volatile compounds. Acceptance of the cultivars studied is associated with high values for MI, pH,
flesh colour parameters (h and L*), and terpenes, highlighting the sensory attributes flesh colour and
fruit flavour. In particular, CDN and SA showed high consumer acceptability among the fig
cultivars studied.
Foods 2020, 9, 619 12 of 16
Table 2. Scores of the sensory descriptive attributes and overall acceptability for the samples of the different cultivars studied and for ripening Stages 2 and 3.
External Appearance Skin Colour Flesh Colour Firmness Sweetness Acid Bitter Juiciness Seeds Fruit Flavour Overall Acceptability
Cultivars
DR 6.30 5.42 5.58 6.35 3.76 1.30 2.93 5.18 3.33 5.84 6.11
CDB 6.53 6.18 5.97 6.80 3.11 1.41 5.14 4.71 4.93 6.70 6.71
BT 6.16 5.04 4.02 5.82 3.97 1.61 4.10 5.00 4.48 4.05 4.37
SA 5.62 5.85 5.67 5.54 4.09 1.22 3.67 5.46 3.81 6.25 6.65
CDN 7.12 7.09 5.23 7.24 3.38 2.32 3.95 4.39 2.64 4.35 5.01
BN 4.92 6.43 5.22 4.97 3.46 2.17 3.80 5.49 3.63 4.83 5.08
CE 6.88 6.27 5.09 6.77 3.25 2.11 3.98
4.74 3.67 4.81 5.68
TV 4.97 6.24 5.71 5.19 2.86 1.61 3.69 4.39 3.32 5.91 4.90
BB 5.59 5.15 5.03 5.26 4.28 1.84 3.00 5.56 4.88 5.21 5.57
Ripening stage
2 6.24 6.09 5.23 6.19 3.37 1.69 3.61 4.95 3.77 5.10 5.40
3 5.77 5.84 5.33 5.80 3.77 1.77 4.00 5.03 3.93 5.55 5.73
PC§ 0.000 0.000 0.006 0.000 0.389 0.032 0.008 0.130 0.000 0.000 0.000
Tukey CI ± 1.60 ±1.49 ±1.64 ±1.52 ±2.26 ±1.10 ±1.89 ±1.75 ±1.77 ±1.73 ±1.45
PS# 0.037 0.230 0.684 0.075 0.210 0.651 0.143 0.738 0.526 0.064 0.117
Numbers in bold type indicate the maximum score of the attribute. Underlined numbers in italics indicate the minimum score of the attribute. § Pc: p-value for
cultivar factor. CI: confidence interval for post-hoc Tukey HSD test. # Ps: p-value for ripening stage factor.
Foods 2020, 9, 619 13 of 16
Figure 5. Loading plots (A and C) and score plots (B and D) after principal component analysis of the varieties, ripening stages, physicochemical, and sensory
parameters and in the planes by three first principal components (PC1, PC2, and PC3). Physicochemical parameters (), weight (W), calibre (C), °Brix (°B), acidity
(Ac), pH, maturation index (IM), rmness (Firm). Colour parameters (), skin h* (hsk), C* (C*sk), L* (L*sk); fesh h* (hfl), C* (C*fl), L* (L*fl). Chemical families of
volatile compounds (), aldehydes (AL), acids (Ac), alcohols (OL), ketones (K), furans (F), pyrazines (P), hydrocarbons (H), terpenes (T), esters (ES). Sensory
parameters (), external appearance (Ext), skin colour (Csk), fresh colour (CFl), texture (Tex), sweetness (Swe), bitterness (Bit), juiciness (Jui), fruit flavour (Fru),
overall acceptability (Acep).
DR
CDB
BT
SA
CDN
BN
CE
TV
BB
s2s3
-1.5
-1
-0.5
0
0.5
1
1.5
2
-2.5 -2 -1.5 -1 -0.5 0 0 .5 1 1.5
PC 3 (13.4%)
PC 1 (27.7%)
Firm
Ac
pH
ºB
IM
Ext
Tex
Csk CFl Fru
Swe
Aci
Bit
Jui
Seed
Acep
H
OL
AL
K
AC
ES
F
PTL*sk
C*sk
husk
L*fl
C*fl hufl
Cal
W
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
-1 -0.5 0 0.5 1
PC 3 (13.4%)
PC 1 (27.7%)
Firm
Ac
pH
ºB
IM
Ext
Tex
Csk
CFl Fru
Swe
Aci
Bit
Jui Seed
Acep
H
OL
AL K
AC
ES
F
P
T
L*sk
C*sk
husk L*fl
C*fl
hufl
Cal
W
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
-1 -0.5 0 0.5 1
PC2 (20.5%)
PC 1 (27.7%)
DR
CDB
BT
SA
CDN
BN
CE TV
BB
s2
s3
-1.5
-1
-0.5
0
0.5
1
1.5
2
-3 -2 -1 0 1 2
PC 2 (20.5%)
PC 1 (27.7%)
A
B
C
D
Foods 2020, 9, 619 14 of 16
Author Contributions: Conceptualisation, C.P.; methodology, M.L.-C.; software, A.I.G.; validation, A.M.;
formal analysis, C.P., A.M.; investigation, C.P., A.I.G., A.M.; resources, A.M., M.J.S.; data curation, C.P.;
writing—original draft preparation, A.M.; writing—review and editing, A.M., M.L.-C., M.J.S., M.d.G.C.;
visualisation, A.M.; supervision, project administration, M.L.-C., M.d.G.C.; funding acquisition, M.L.-C. All
authors have read and agreed to the published version of the manuscript.
Funding: This research was funded by Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria
(INIA) Ministerio de Ciencia e Innovación (Spain), grant number RTA2010-00123; and Junta of Extremadura,
grant nunmbers GR18165 and GR18196. Cristina Pereira is the beneficiary of the pre-doctoral grant (BOE n 31,
Sec. III. pág.: 12862) from INIA.
Acknowledgments: The authors are grateful to M. Cabrero and J. Barneto for technical assistance.
Conflicts of Interest: The authors declare no conflict of interest.
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... In the present study, the lowest pH values were obtained in the accession 'TMAF 2', while the highest pH values were observed for 'TMAF 8'. The pH juice values reported in the present study are similar to the values previously found by Bostan et al. (1998), Silva et al. (2009), Polat and Caliskan (2008), Petkova et al. (2019) and Pereira et al. (2020) but with some discrepancies. The disagreement in the results is probably related to differences in the maturity stage, genotypes used and environmental conditions (Pereira et al., 2017). ...
... Higher or lower discrepancies in terms of SSC, TA, pH juice and RI values among different studies and our results can be explained by the influence of environmental conditions on fruit quality and also with genotype properties, maturity stage and fruit position in canopy or bush. For example, with increasing maturity, the pH value increase, which result in a less acidic product (Pereira et al., 2020). ...
Article
During two consecutive years, we investigated main physical and chemical properties of 10 native fig accessions grown in situ under atypical i.e. moderate climate of Serbia. This study represents the first detailed research on the analysis of different types of fig accessions and evaluation of their main fruit quality attributes. Results showed that all evaluated traits significantly varied among accessions, whereas influence of year and interaction accession £ year was minor. Fruit weight (FW) and fruit size were much higher in lighter accessions compared to dark colored ones. Three accessions ('TMAF 5', 'TMAF 9' and 'TMAF 10') had soluble solids content (SSC) higher than 20°Brix. 'TMAF 8' with brighter skin had the sweetest fruits compared to the rest. 'TMAF 7' accession with yellow-green skin had smaller values of SSC, pH juice, ripening index (RI) and ash and low to moderate titratable acidity (TA). This accession also had the lowest content of phenolic compounds. In contrast, dark skin fruits exhibited a higher total polyphenol content (TPC) compared to lighter fruits. The majority of significant correlation coefficients were found in the characteristics representing FW with fruit dimensions i.e. fruit size and fruit shape indexes. Also, strong correlations between the amounts of total phenolics, total flavonoids (TFC), antioxidant capacity (TAC), chlorophylls (a, b) and carote-noids were found. Principal component analysis (PCA) revealed that the first three components explained 82.20% of the total variation, where fruit physical and chemical traits contributed most of the total variation. Since the knowledge and experience about growing figs in Serbia is extremely modest, it is necessary to continue testing in the future.
... However, the sensory scores of T 3 products were significantly higher that control samples for all sensory attributes. This increase in the sensory quality of the fig-enriched products might be attributed to superior taste, aroma and texture of the figs (Pereira et al., 2020). Figs are rich in volatile aroma compounds such as ethyl acetate, hexanal, β-caryophyllene, limonene, (E)-2-hexenal, and octanal (Pereira et al., 2020). ...
... This increase in the sensory quality of the fig-enriched products might be attributed to superior taste, aroma and texture of the figs (Pereira et al., 2020). Figs are rich in volatile aroma compounds such as ethyl acetate, hexanal, β-caryophyllene, limonene, (E)-2-hexenal, and octanal (Pereira et al., 2020). The lower scores of T 3 products compared to T 2 products were due to an intense and excessive fig flavour. ...
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The aim of the present study was to develop an Aloe vera–based bioactive edible film for improved lipid oxidative and microbial stability of frozen dairy products. Fig enriched kulfi was used as a model system and developed using different levels of fig powder viz. 0% (control), 2% (T1), 3% (T2), and 4% (T3). Addition of fig powder significantly (p < 0.05) increased the antioxidant capacity (2-2-azinobis-3ethylbenthiazoline-6-sulphonic acid and 1, 1-diphenyl-2-picrylhydrazyl radical scavenging activity, total phenolic content), melting resistance (up to 16%), crude fibre content (up to 183%), and the hardness (N) of the product. Highest scores were observed for T2 products for all sensory attributes. The T2 products were packaged in an edible film containing 15% A. vera extract (AE (15%)) and stored at − 18 ± 1 °C. The samples were taken on 0, 45, 90, 135, and 180th day and evaluated for storage stability. The A. vera extract enhanced antioxidant capacity and antimicrobial properties of the film against E. coli. Products packaged in AE (15%) film showed significantly (p < 0.05) lower values for TBARS (mg malondialdehyde/kg), free fatty acids (FFA, % oleic acid), peroxide value (meq/kg), and microbial counts (total plate, psychrophilic and yeast/mould, log10 cfu/g) compared to control samples (without film) during storage. The mean values for TBARS, FFA, total plate, and yeast/mould count on 180th day for AE (15%) packaged/control samples were 0.618/1.00, 0.478/0.806, 4.09/5.95, and 1.64/2.39, respectively. The developed film significantly improved the storage stability of kulfi and can be used for improving the storage quality of frozen dairy products.
... Although there have been various studies on the aroma and phenolic contents of fig fruits (Grison-Pigé et al. 2002;Gozlekci et al. 2011;Vallejo et al. 2012;Oliveira et al. 2010a;Oliveira et al. 2010b;Villalobos et al. 2018;Pereira et al. 2020), no study has been found on aroma-active compounds. In addition, no comprehensive study is available in the present literature on the aroma, aroma-active and bioactive compounds in the peels and pulps of popular Turkish fig cultivars including cvs. ...
... A total of 59 compounds were determined including terpenes (21 compounds), alcohols (12 compounds), esters (10 compounds), aldehydes (10 compounds), ketones (4 compounds), acid (1 compound) and lactone (1 compound). Similar findings in various previous studies on fig fruits were reported (Grison-Pigé et al. 2002;Oliveira et al. 2010a;Oliveira et al. 2010b;Gozlekci et al. 2011;Villalobos et al. 2018;Pereira et al. 2020). As shown in Table 2, a total of 57 and 58 aroma compounds were detected in the pulps and peels of cv. ...
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Fig fruit (Ficus carica L.) is highly popular and consumed in the world for its nutritional and health benefits. The aroma, aroma-active, total phenolics and antioxidant activity of the peels and pulps of fig samples from two popular Turkish cultivars (Sarilop and Bursa Siyahi) were investigated in this study. A total of 57 and 58 aroma compounds were quantified in the pulps and peels of Sarilop cultivar while the pulps and peels of Bursa Siyahi cultivar had a total of 54 and 55 aroma compounds, respectively. The terpenes, followed by esters and alcohols, were the most dominant aroma compounds in all fig samples. The results of the gas chromatography-mass spectrometry-olfactometry (GC-MS-O) analysis showed that a total of 19 aroma-active compounds were detected in all samples. Based upon the FD (flavour dilution) factor, the most potent aroma-active compounds were benzyl alcohol for the pulps of cv. Sarilop; β-caryophyllene and benzyl alcohol for the peels of cv. Sarilop; DL-limonene, acetoin and benzyl alcohol for the pulps of cv. Bursa Siyahi and DL-limonene, acetoin and β-caryophyllene for the peels of cv. Bursa Siyahi. It was determined that the peels of Bursa Siyahi cultivar had significantly higher total phenolics and antioxidant activity.
... The volatiles compounds were identified as hydrocarbons, aldehydes, alcohols, ethers, esters, ketones, carboxylic acids, phenolics acids, monoterpenes and sesquiterpenes. The chemical composition was varied according to the parts of the fruit and stages of development (pollinated and unpollinated) (Nawade et al., 2020;Palassarou et al., 2017;Pereira et al., 2020;Russo et al., 2017;Soltana et al., 2017;Trad et al., 2017;Villalobos et al., 2018). ...
Article
The aim of this review was to compile the main reports over the last 5 years concerning the Ficus spp. fruits (Moraceae family) based on chemistry, properties, and applications as products. About 30 Ficus spp. fruits were reported focusing on their chemical composition rich in phenolic acids such as gallic, caffeic and chlorogenic acids, as well as quercetin and cyanidin derivatives. The fruits from Moraceae family presented mainly antioxidant and antimicrobial properties in addition to other functional properties to consumers health. Therefore, these fruits can be successfully considered by the food industry for the development of new products with high added value and also be considered a source of bioactive compounds.
... However, it should be noted that, although the fig tree (Ficus carica L.) is the most important species at a commercial level, it consists of more than 600 varieties with significant genetic diversity and verified by numerous studies [3,[9][10][11][12]. In this sense, and given that the varietal variation has a direct influence on the physicochemical and pomological characteristics of the fruits, the objective and specific characterization of each of the commercial varieties of the fig tree is necessary. ...
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Although most of the published articles generalize with the fruit of the fig tree (Ficus carica L.), the differentiation between fig and breba is increasingly common in the bibliography. In this regard, keep in mind that the fig tree generally produces two crops a year, the parthenocarpic breba, also called as early fig, and the main non-parthenocarpic crop, the fig proper. In this study, four brebas varieties (‘Colar’, ‘SuperFig1’, ‘Cuello de Dama Negro’ and ‘San Antonio’) were selected in order to identify compositional, nutritional, and chemical diversity. These varieties were chosen for their commercial relevance in Spain. Color (internal and external), fruit and peel weight, size, pH, total soluble solids (TSS), titratable acidity (TA), maturity index (MI), sugar, and organic content were determined for all the breba fruits samples. In addition, polyphenolic profile, amino acids, and volatile aromatic compounds were also identified. The varieties ‘Colar’ and ‘SuperFig1’ showed the highest fruit weight and size, while ‘Cuello de Dama Negro’ presented the higher pulp yield. The higher organic acid and sugar contents were determined for ‘SuperFig1’ and ‘Cuello de Dama Negro’, respectively. Although in low concentrations, the phenolic compound quercetin 3-(6-O-acetyl-beta-glucoside) and the amino acid tyrosine were only detected in the ‘’Cuello de Dama Negra’ and ‘SuperFig1’ fruits, respectively. Of the eighty volatile aromatic compounds identified, only eight were common in four varieties. An important knowledge gap was identified in relation to the characterization of the two Ficus carica L. crops, that is, the differentiation and specification in the literature when working with brebas and/or figs.
... Benzaldehyde was also highly abundant in TH and AZ figs. This molecule is one of the major aromatic aldehydes that contribute greatly to fig aroma, and it is released from the oxidation of benzyl alcohol through the shikimic acid pathway (Pereira et al., 2020). Similar abundance was reported by Palassarou et al. (2017) in the dried pulp of a Peloponnese fig cultivar. ...
... Benzaldehyde was also highly abundant in TH and AZ figs. This molecule is one of the major aromatic aldehydes that contribute greatly to fig aroma, and it is released from the oxidation of benzyl alcohol through the shikimic acid pathway (Pereira et al., 2020). Similar abundance was reported by Palassarou et al. (2017) in the dried pulp of a Peloponnese fig cultivar. ...
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Aroma is one of the essential parameters that determine fruit quality. It is also an important feature of varietal characterization and so valuable for agro-biodiversity identification and preservation. In order to characterize changes in the aroma fingerprint through fig development, the main objective of the present research was to study the volatile organic compound (VOC) profiles of figs (Ficus carica L.) from three cultivars, Taamriwthe (TH), Azegzaw (AZ), and Averkane (AV), at three ripening stages (unripe, ripe, and fully ripe). Analyses was performed using Headspace Solid-phase Microextraction and gas chromatography coupled with mass spectrometry. Results revealed the presence of 29 compounds that were grouped into different chemical classes. Aldehydes comprised the most abundant VOCs identified in all the studied figs, while alcohols, ketones, and terpenes comprised the minor compounds found in TH, AZ, and AV figs, respectively. Different aroma descriptors were identified throughout the ripening stages of figs; fruity and green aromas were dominant in all cultivars, while a fatty aroma scarcely occurred in figs. A gallery plot representation demonstrated that certain VOCs differentiate the studied cultivars and the different ripening stages of figs. Principal component analysis findings demonstrated characteristic VOCs of distinct ripening stages and cultivars, those VOCs can be used as fingerprints to distinguish different cultivars and/or ripening stages.
Article
To improve direct sun drying, small drying tunnel units, elevated above the ground and covered by insect‐proof nets, were designed. We investigated the effect of these locally made solar dryers, placed in open air and under plastic greenhouse, on dried fig quality of three local varieties (two San Pedro types and one Smyrna type). The results showed that fruit lightness and yellowness were improved when figs were dried under plastic greenhouse. No significant effects of variety and drying methods were registered for total soluble solids, and glucose and fructose contents. A total of 104 volatile compounds were identified in Tunisian dried figs. Most of volatiles except acetic acid were influenced mostly by variety. The sensory analysis revealed significant differences between drying techniques. Figs dried under plastic tunnel were the most appreciated. Solar dryer under plastic tunnel could be a good alternative for rural farmers to substitute the traditional sun drying techniques. This work provides beneficial knowledge for improving the appearance and organoleptic quality of dried figs considering combined effect of variety and drying method. Plastic tunnel dryer is a good alternative for rural farmers to substitute the traditional open air sun drying. This method enhances the quality of products with minimum costs and short duration of dehydration.
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Lucuma hypoglauca Standley, locally named choch, is apparently native from Southern Mexico, but is also cultivated in Central and South America. The fruit is consumed fresh and it is widely accepted in diverse regional markets. Owing to the great potential of commercialization as an exotic fruit, it is important to analyze the aroma of this fruit. The objective of this present study was to analyze the volatile compounds causing the aroma of choch fruit. The volatile compounds of choch fruit were isolated by simultaneous distillation-solvent extraction (SDE) and analyzed by gas chromatography-flame ionization detector and gas chromatography-mass spectrometry. A total of 30 volatile constituents were detected, which represented 2.31 mg kg⁻¹ of the fruit. The composition of the volatile constituents of the fruit included 12 ketones (27.5% of the total volatile composition), seven terpenes (64.8%), four esters (4.1%), four alcohols (2.2%), two aldehydes (1.1%), and a sulfur compound (0.4%). The major compounds were (E)-β-caryophyllene (56.3% of the total volatile composition), with lesser amounts of 3-hydroxy-2-butanone (6.1%), 2-pentanone (5.6%), and (E)-3-penten-2-one (5.6%). By application of odor activity values (OAVs), six constituents were considered as aroma-active volatiles, of which the most important were (E)-3-penten-2-one, (E)-β-caryophyllene, methional, 3-methylbutanal, 3-heptanone, butanal, and 3-hexanone.
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The quality characteristics of brebas for fresh consumption from nine fig varieties at different commercial ripening stages were determined. Physicochemical and nutritional parameters were analyzed for both skin and flesh, and the findings were compared among varieties and ripening stages. The results revealed that the major nutrient components in brebas are sugars, such as glucose and fructose, and mineral elements, including K, Ca, P, and Mg. Most nutrients evaluated are important elements that contribute to the commercial quality of brebas. “Brown Turkey” and “Banane” varieties showed the highest weight and width. The concentrations of the monomer sugars studied were higher in flesh than skin, and the “Cuello Dama Blanco” and “Colar Elche” varieties showed the highest content of these sugars. The early ripening stage, coinciding with a fast increase in fruit size, was also associated with a higher fiber and protein contents, TA, and firmness for “Banane,” “Brown Turkey,” and “Blanca Bétera” varieties. Conversely, the later ripening stage was related to a significant increase of TSS, MI, and color intensity. Finally, no clear changes in the concentrations of organic acids were observed between different varieties and commercial ripening stages.
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The present article was designed with the aim to develop processing technology for preparation of fig (Ficus carica L.) fruits powder (Deanna variety) and the prepared fig powder was subsequently utilized in value added product like burfi (Indian cookie). In contrast to fig pulp and dried figs, the fig powder was found to be superior in terms of yield and ease of processing technology. Fig powder also open further fields of application that may promote fig powder processing at industrial scale in future. The products prepared by processing of figs viz. fig powder and fig burfi were chemically and sensorial assessed and also assessed for their economical feasibility and compared with market samples. Fig powder incorporated burfi was nutritionally rich in terms of fiber (3.7 %), potassium (0.464 %) and protein (13.12 %). The prepared product was found to be low cost as compared to the similar market products.
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The effect of passive modified atmosphere packaging (MAP) on the volatile compound profile of fig cultivars ‘Cuello Dama Negro’ (CDN) and ‘San Antonio’ (SA) during post-harvest storage was evaluated, to determine its impact on flavour and overall acceptability. Fruit was packaged using three types of microperforated films (ø = 100 μm): M10 (16 holes), M30 (five holes) and M50 (three holes); and a control macroperforated film (ø = 9 mm; five holes). The fruit were stored at 0 °C for 14 d. Fruit were also analysed after a period of shelf life at 20 °C for 2 d after cold storage. The volatile profile and its evolution during cold storage depended strongly on the fig cultivar. CDN displayed only moderate changes in the overall volatile profile for both, control and microperforated batches, during storage at 0 °C. In contrast, the volatile compound profile of SA was largely influenced by the duration of the cold storage and the shelf-life. Under refrigeration conditions, the microperforated M50 films allowed to delay changes in the volatile profile of SA, without negative influence on the fig flavour.
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Fig (Ficus carica L.) is one of the most important fresh and dried fruits for both consumers and food industry throughout world and is produced in a limited number of countries. As a leader producer in the world, Turkey has important fig genetic resources as well. However in most parts of the country, in particular coastal regions, local fig genotypes are continuously subjected to genetic erosion and therefore, it is necessary to determine, collect, describe and also to maintain them in situ and ex situ. This study we aimed to evaluate local fig germplasm in Alanya and Kemer districts in Mediterranean region of Turkey. The results showed that the investigated pomological traits of fig genotypes displayed significant differences within both districts. Fig samples collected from Alanya are more suitable for making marmalade and jam because they had relatively small fruits, while figs sampled from Kemer are generally considered good as fresh consumption due to their relatively big fruit size. These valuable fig genetic resources are under in-situ conservation to use in future breeding programmes.
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The effect of two fruit maturity stages on the quality attributes of four fresh fig cultivars was examined, including consumer acceptance and antioxidant capacity. Fig quality attributes such as weight, soluble solids concentration (SSC), titratable acidity (TA), SSC:TA, firmness, antioxidant capacity, and consumer acceptance varied by cultivar. Fig cultivars harvested at the advanced maturity stage (''tree ripe'') had lower TA and firmness but higher weight, SSC, and SSC:TA than figs harvested at ''commercial maturity.'' Fig maturity did not affect antioxidant capacity, but tree ripe figs had higher consumer acceptance than commercial maturity figs. SSC was more highly correlated with consumer acceptance than TA or SSC:TA, but other factors may also be important in controlling this relationship. Cultivars with high SSC and firmness, at a maturity stage high enough to tolerate harvesting and postharvest handling, should be selected to develop the fresh fig industry. Because fig firmness is a concern, changes to packaging should be evaluated to protect the flavor of advanced maturity figs during postharvest handling.