Aloe vera gel coating maintains quality and safety of ready-to-eat pomegranate arils

Postharvest Biology and Technology 86 (2013) 107–112

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Aloe vera gel coating maintains quality and safety of ready-to-eat pomegranate arils Domingo Martínez-Romero a,∗ , Salvador Castillo a , Fabián Guillén a , Huertas M. Díaz-Mula a , Pedro J. Zapata a , Daniel Valero a , María Serrano b a b

Department of Food Technology, EPSO, University Miguel Hernández, Ctra. Beniel km. 3.2, 03312 Orihuela, Alicante, Spain Department of Applied Biology, EPSO, University Miguel Hernández, Ctra. Beniel km. 3.2, 03312 Orihuela, Alicante, Spain

a r t i c l e

i n f o

Article history: Received 9 April 2013 Accepted 16 June 2013 Keywords: Aloe vera Edible coating Microbial spoilage Firmness Colour Minimally processed

a b s t r a c t Several postharvest treatments were performed on pomegranate arils prior to storage in rigid polypropylene boxes for 12 days at 3 ◦ C: water (control), ascorbic + citric acids (at 0.5 or 1%), Aloe vera gel (at 50 or 100%), 50% A. vera gel + 0.5% ascorbic and 0.5% citric acid, and 100% A. vera gel + 1% ascorbic and 1% citric acid. A. vera (alone or in combination with acids) led to lower CO2 and higher O2 concentrations inside the packages compared with arils treated with water (control). With respect to quality attributes, A. vera coatings led to firmness retention and increased levels of total anthocyanins and total phenolics. In addition, A. vera treatments led to significantly lower counts for both mesophilic aerobics and yeast and moulds. Sensory analysis scores for flavour, texture, aroma, colour and purchase decision were higher in arils treated with A. vera, especially in those arils treated with 100% A. vera + 1% ascorbic and citric acids. Finally, no off-flavours in pomegranate arils were perceived by judges as a consequence of A. vera gel treatment. © 2013 Published by Elsevier B.V.

1. Introduction Pomegranate fruit (Punica granatum L.) is one of the oldest of edible fruit, cultivated extensively in Mediterranean countries including Spain, and generally consumed as fresh (arils) or juice. Over recent years there has been a great increase in pomegranate commercial farming, due to the high quality attributes of pomegranate arils and their potential health benefits, such as anti-mutagenic, anti-hypertension, antioxidant activities and even antitumor properties in vivo and in vitro (Heber and Bowerman, 2009). Pomegranates have a non-climacteric ripening pattern, but are characterized by a reduced shelf-life due to acceleration of loss of quality loss. The growing demand for minimally processed fruit has led to increasing research on designing and implementing methods for maintaining quality of these highly perishable fruit. In this sense, minimally processed “ready-to-eat” pomegranate arils in modified atmosphere packaging (MAP) have become very popular due to their convenience, sensory attributes and health benefits (Ayhan and Es¸türk, 2009). However, maintaining the nutritional and microbial quality of pomegranate arils is a major challenge, since minimally processed arils easily loose quality attributes such

∗ Corresponding author. Tel.: +34 96 6749720; fax: +34 96 6749678. E-mail address: [email protected] (D. Martínez-Romero). 0925-5214/$ – see front matter © 2013 Published by Elsevier B.V. http://dx.doi.org/10.1016/j.postharvbio.2013.06.022

as texture and colour, together with an increase in microbial spoilage (Gil et al., 1996; Caleb et al., 2012). Recently, the postharvest shelf-life of MA-packaged arils was shown to be limited to 10 days due to fungal growth, and only 7 days when taking into account data for flavour and aroma (Caleb et al., 2013). Moreover, the application of UV-C before MA-packaging could not increase the shelf-life beyond 10 days since the microbial limit was reached (López-Rubira et al., 2005). Thus, new alternatives are needed to reduce the microbial population on pomegranate arils under MA conditions and to delay quality loss. In this sense, Aloe vera gel applied as an edible coating has been found to be effective in quality retention and reduction of microbial spoilage of several whole fruit such as sweet cherry, table grape and nectarine (Valverde et al., 2005; Martínez-Romero et al., 2006; Ahmed et al., 2009; Castillo et al., 2010). However, few studies have been devoted to the use of A. vera gel on minimally processed fruit, apart from recent reports on kiwifruit or apple slices, for which Aloe gel-coated slices showed improved quality during storage (Chauhan et al., 2011; Benitez et al., 2013). Interestingly, the antifungal activity of Aloe gel from several species has been correlated with the content of aloin, one of the major phenolic compounds of Aloe leaves (Zapata et al., 2013). When edible coatings are applied to minimally processed fruit, the incorporation of citric acid and ascorbic acid have positive effects on reducing browning and microbial spoilage (Pérez-Gago et al., 2010). Thus, the objective of this work was to investigate for the first time the

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effect of A. vera gel (alone or in combination with ascorbic and citric acids) applied as a coating on the overall quality of minimally processed pomegranate arils during storage under MAP conditions.

Internal odour was evaluated immediately after opening the boxes according to the protocol described below (Section 2.5). 2.3. Microbiological analysis

2. Materials and methods 2.1. Plant material and experimental design Pomegranate fruit (P. granatum L., cv. Mollar de Elche) were harvested at commercial ripening (fully mature according to commercial practice) from a plot located in Elche (Alicante) and immediately transported to the laboratory. Pomegranates with defects (sunburn, cracks, bruises and cuts in the husk) were discarded and only fruit with healthy outer skins and uniform in size and appearance were used. Husks (about 300) were carefully cut with sharpened knives and arils manually extracted. The arils were collected in a tray, washed in a solution containing 100 ␮L L−1 chlorine (NaOCl) for 5 min and further rinsed in tap water, drained and excess water removed from arils with paper towels, as reported by López-Rubira et al. (2005). The arils were divided into 7 lots for the following treatments: (a) water (control washed arils); (b) acids 0.5% (citric acid 0.5% + ascorbic acid 0.5%); (c) acids 1.0% (citric acid 1.0% + ascorbic acid 1.0%); (d) A. vera 50% (A. vera gel diluted with distilled water 50–50 v/v); (e) A. vera 100% (A. vera gel); (f) A. vera 50% + acids 0.5% (treatments b + d); (g) A. vera 100% + acids 1.0% (treatments c + e). Acid treatments (0.5% or 1%, treatments b and c, respectively) were prepared by dissolving citric or ascorbic acid powder (SigmaAldrich, Madrid) at individual concentrations of 0.5 or 1.0%, the pH of the solutions being 2.2 and 2.6, respectively. Freshly A. vera gel was prepared according to a previous report (Navarro et al., 2011). Briefly, for each leaf the spikes along their margins were removed before longitudinally slicing to separate the rind from the inner leaf gel. The gel fillets were crushed to yield a mucilaginous gel which was filtered to discard the fibrous fraction, this gel being used for treatment A. vera 100%. The gel diluted with distilled water (50:50 v/v) was used for the A. vera 50% treatment. In both cases, acids (citric acid and ascorbic acid powder) were added at 0.5% or 1.0%, and pH of the gels adjusted to 3.7. Treatments were performed by dipping the arils in the corresponding solution for 5 min, then drained using a colander, collected on a tray and left to dry. After coating, arils (130 g) were placed directly in rigid polypropylene boxes (280 mL) and covered with airtight lids (Lealplast S.L., Murcia, Spain). A silicone septum was deposited on the lid for gas extraction and O2 and CO2 quantification. For each treatment 30 boxes were used, from which 10 were sampled after 4, 8 and 12 days of storage at 3 ◦ C and 90% RH for analytical determinations, respectively. For day 0 measurements the arils (10 boxes) after chlorine washing were used. In addition, microbial analyses were also performed on 10 samples before chlorination. 2.2. Gas composition and odour The gas composition was measured inside each box and treatment by measuring the CO2 and O2 concentrations. Measurements were performed in duplicate by withdrawal of 1 mL of the headspace atmosphere using an air-tight syringe through the silicone septum and injected into a gas chromatograph GC 14B (Shimadzu, Tokyo, Japan) equipped with a thermal conductivity detector (TCD). CO2 and O2 were separated on a molecular sieve 5A column, 80–100 mesh (Carbosieve SII. Supelco Inc., Bellefonte, USA), of 2 m length and 3 mm i.d. Oven and injector temperature were 50 and 110 ◦ C, respectively. Helium was used as carrier gas at a flow rate of 50 mL min−1 . Results (mean ± SE) were expressed as kPa O2 and kPa CO2 inside the boxes.

For each box and treatment, samples (10 g) were obtained under sterilized conditions (laminar fume cupboard, gloves and scalpels), which were homogenized in 90 mL of sterile peptone water using a stomacher (Model Seward, Laboratory Blender Stomacher 400, London, UK). Serial dilutions were carried out and 1 mL was added to plate count agar for mesophilic aerobic and for mould and yeast counts (PetrifilmTM Aerobic Count Plate, Laboratories 3MTM Santé, France), and only counts of 30–300 colony forming units (CFU) were considered. The same procedure was carried out on recently harvested arils (day 0) and after chlorination. All plates were incubated for 3 days at 25 and 30 ◦ C for mesophilic and mould and yeast, respectively, and results (mean ± SE) expressed as CFU g−1 . 2.4. Aril quality parameters Aril firmness was determined in each box using a TX-XT2i Texture Analyzer (Stable Microsystems, Godalming, UK) interfaced to a PC, and a forward extrusion cell. The cell was filled at half with arils and compression force (3% of the aril cell height) was applied using a 40 mm flat probe. The results were expressed as force-deformation ratio (N mm−1 ) and are means ± SE. Total soluble solids (TSS) were determined in duplicate in the juice obtained from 10 g of each box with a digital refractometer Atago PR-101 (Atago Co. Ltd., Tokyo, Japan) at 20 ◦ C, and expressed as % (◦ Brix). Total acidity (TA) was determined in the same juice in duplicate by automatic titration (785 DMP Titrino, Metrohm) with 0.1 N NaOH up to pH 8.1, using 1 mL of diluted juice in 25 mL distilled H2 O, and results expressed as g malic acid equivalent per 100 g−1 fresh weight. Results were expressed as mean ± SE. Colour was determined with a Minolta colorimeter (CR200, Minolta Camera Co., Japan) and expressed by the CIE Lab System. Results were means ± SE of 3 determinations for each sample and expressed as Hue angle (arctg b*/a*). Total phenolics and total anthocyanins were determined according to a previous report (Sayyari et al., 2010). Briefly, phenolic extraction was performed using water:methanol (2:8) containing 2 mM NaF (to inactivate polyphenol oxidase activity and prevent phenolic degradation) and quantified using the Folin–Ciocalteu reagent. Results were expressed as mg gallic acid equivalent 100 g−1 FW. Total anthocyanins were calculated from the above methanolic extract as cyanidin 3-glucoside equivalent (molar absorption coefficient of 23,900 L cm−1 mol−1 and molecular weight of 449.2 g mol−1 ) and results (mean ± SE) expressed as mg 100 g−1 FW. 2.5. Sensory evaluation Sensory analyses to compare the internal package odour of treated and control arils were carried out by 10 trained adults, aged 25–50 years (5 female and 5 male). The panel was trained in a pretest for evaluating the aroma of pomegranate arils. A laboratory of sensory analyses with an individual booth for each panellist was used. For each treatment and sampling date, the ten boxes were opened and each judge evaluated immediately the box head space odour on a ranked scale of 5 to 1, where 5 = fresh fruit, 4 = ripe, 3 = over-ripe, 2 = slightly fermented, and 1 = off-odour. The same panel evaluated the following aril quality attributes: colour, aroma, texture, flavour and purchase decision. Panellists were pre-trained in aril visualization, smelling and tasting, and each judge evaluated 1 sample for each treatment. Samples were blind labelled with random three digit codes, and the sample order

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Water Acids 0.5 % Acids 1.0 % A. vera 50 % A.vera 100 % A. vera 50% + Acids 0.5 % A. vera 100 % + Acids 1.0 %

15

20

15

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10 Water Acids 0.5 % Acids 1.0 % A. vera 50 % A.vera 100 % A. vera 50% + Acids 0.5 % A. vera 100 % + Acids 1.0 %

5

O2 Concentration (kPa)

CO2 Concentration (kPa)

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Fig. 1. CO2 and O2 concentration (kPa) inside packages of control and treated arils during storage. Data are the mean ± SE of measurements performed in duplicate in 10 boxes.

was randomized. During evaluation, panellists rinsed their palates with room temperature water between samples. The rating for each characteristic was based on a five-point scale (5 to 1) with 5 = like extremely (very characteristic of the fruit), 4 = like moderately, 3 = neither like nor dislike like (limit of acceptance for consumers), 2 = dislike moderately and 1 = dislike extremely (non-characteristic of the product). 2.6. Statistical analysis Data for the physical, chemical, microbiological and sensory parameters were subjected to analysis of variance (ANOVA). Sources of variation were time of storage and treatments. Mean comparisons were performed using HSD Tukey’s test to examine if differences between treatments and storage time were significant at P < 0.05. All analyses were performed with SPSS software package v. 11.0 for windows.

previous reports in which concentrations of 5–15 kPa CO2 are recommended for aril storage under modified atmosphere packaging (MAP) conditions, in our study the arils treated with A. vera gel alone or with the addition of acids would fit within the recommended range (Gil et al., 1996; Gorny, 1998; López-Rubira et al., 2005). To evaluate the impact of the treatments on head space aroma, panellists were asked to test the odour of the packages immediately after opening, and results at day 8 of the experiment are shown in Table 1. Control and 1.0% acids treated arils had scores of ca. 3.6, which means odour of over-ripe fruit, while the remaining treatments had scores of 4.4–4.8, that is, aroma of fresh fruit. At day 12, scores for all treatments were below 3, over-ripe aroma and occurrence of off-flavour, excepting those arils treated with A. vera gel at 100% alone or with the addition of acids at 1%, which scored ∼ =3.8 (data not shown). According to the aroma results, shelf-life of arils coated with A. vera gel at 100% alone or with ascorbic and citric acid could be extended up to 12 days, while control and 1% acids treated arils had a shelf-life of 8 days.

3. Results and discussion

3.2. Aril quality parameters and bioactive compounds

3.1. Gas composition and odour

At harvest, the content of total soluble solids (TSS) was 16.7 ± 0.1 g 100 g−1 , and significantly decreased after 8 days of storage for all samples and without significant differences among treatments (Table 1). In contrast, total acidity at harvest (0.33 ± 0.01 g 100 g−1 ) decreased significantly during storage in control arils and in those coated with A. vera gel at either 50 or 100%. However, in those arils treated with acids (alone or in combination with A. vera gel) total acidity was maintained or even increased after 8 days of storage (Table 1), probably due to acid diffusion from the treatment solutions into the arils. In fact, the ripening index (TSS/TA ratio) increased from initial values of ∼ =50 to ∼ =58 in both control and A. vera gel (at 50 or 100%) treatments, and significantly decreased in those arils treated with acids alone or in combination with A. vera gel. This increase in acidity could be considered as a positive characteristic from the acceptance point of view, since ‘Mollar de Elche’ is categorized as a low acidic cultivar (Mirdehghan et al., 2007) compared with acidic Iranian cultivars, such as ‘Malas Saveh’ (Sayyari et al., 2009). These results are in agreement with a previous report in which low variations for both TSS and TA have been observed in arils coated with chitosan at 0.25, 0.5 and 1% after 12 days of storage (Ghasemnezhad et al., 2013).

The concentrations of CO2 increased and O2 decreased significantly over time inside the package headspace although significant differences existed among treatments (Fig. 1). The highest CO2 concentration was found for arils treated with water (control) and the lowest for those treated with A. vera 100%, with values being ∼ =17 and 9 kPa, respectively. With respect to O2 concentration at the end of the experiment, two different groups were found. One group was arils treated with water, acids at 0.5 and 1.0%, in which O2 levels of ∼ =8 kPa were reached, and the other group from treatments in which A. vera was used, either alone or in combination with acids in which significantly higher O2 concentrations (ca. 10 kPa) were found at the end of storage. Results suggested that all treatments inhibited respiration rates of arils during storage, the effect being higher with the use of A. vera gel, especially at 100%. This reduction in respiration rate has been also observed in other non-climacteric fruit such as sweet and sour cherry (Martínez-Romero et al., 2006; Ravanfar et al., 2012) and table grape (Valverde et al., 2005) coated with A. vera gel. In the case of climacteric fruit, such as nectarines, A. vera gel treatment led to lower respiration rates with respect to controls (Ahmed et al., 2009; Navarro et al., 2011). Taking into account

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Table 1 Results for total soluble solids (TSS, g 100 g−1 ), total acidity (TA, g 100 g−1 ), ripening index (TSS/TA ratio) and odour scores from pomegranate arils at day 0 and after 8 days at 3 ◦ C as affected by treatment.a Treatment

Water Acids 0.5% Acids 1.0% A. vera 50% A. vera 100% A. vera 50% + acids 0.5% A. vera 100% + acids 1.0%

Total soluble solids (TSS)

Total acidity (TA)

Ripening Index (TSS/TA)

Odour scores

Day 0

Day 8

Day 0

Day 8

Day 0

Day 8

Day 0

Day 8

16.7 ± 0.1 a

15.2 14.9 15.7 15.0 15.2 15.1 15.6

0.33 ± 0.01 a

0.26 0.32 0.39 0.26 0.26 0.34 0.41

50.61 ± 0.22 a

58.46 46.56 40.26 57.69 58.46 44.41 38.05

5.0 a

3.7 4.4 3.6 4.6 4.7 4.8 4.4

± ± ± ± ± ± ±

0.1 b 0.1 b 0.1 b 0.1 b 0.1 b 0.2 b 0.2 b

± ± ± ± ± ± ±

0.02 b 0.01 a 0.02 a 0.01 b 0.02 b 0.01 a 0.03 c

± ± ± ± ± ± ±

0.54 b 0.21 c 0.28 d 0.64 b 0.36 b 0.29 c 0.19 d

± ± ± ± ± ± ±

0.2 b 0.2 c 0.2 b 0.3 ac 0.2 ac 0.3 ac 0.3 c

a Data are the mean ± SE of determinations performed in 10 replicates. For each parameter different letters show significant differences (P < 0.05) from day 0 to day 8 and among treatments.

have been identified: cyanidin-3 glucoside, delphinidin-3 glucoside, pelargonidin-3 glucoside, cyanidin-3,5 diglucoside and pelargonidin-3,5 diglucoside, the major being cyandin-3 glucoside (Sayyari et al., 2010). Fig. 3 shows the content of total anthocyanins after 8 days of storage, in which the concentration increased significantly in those arils treated with acids (alone or in combination with A. vera gel) or A. vera gel at 100%, the values being significantly higher than those observed for control arils. With respect to total phenolics (Fig. 3), the concentration at day 0 was 107.1 ± 2.3 mg 100 g−1 and decreased to 94.8 ± 4.1 mg 100 g−1 after 8 days of storage in control arils, while no significant changes were observed in those arils treated with A. vera gel (50 or 100%). In treatments with acids (alone or in combination with A. vera gel), a significant increase in total phenolics occurred after 8 days of storage, especially in those coated with A. vera gel 100% + acids at 1% (167.2 ± 5.3 mg 100 g−1 ). During postharvest storage of pomegranates, a reduction of total phenolics has also been reported (Valero and Serrano, 2010; Sayyari et al., 2011), while chitosan used as a coating delayed the decrease in total phenolics that occurred in control pomegranate arils stored at 4 ◦ C in rigid polyethylene boxes for 12 days, according to our results with A. vera gel coating (Ghasemnezhad et al., 2013) and from those observed in chitosan treated whole fruit (Varasteh et al., 2012). When linear regressions were performed, a positive correlation was found between total phenolics and total anthocyanins (y = 1.33 x + 27.33; R2 = 0.563), suggesting that anthocyanins are the main phenolic compounds in pomegranate arils, according to a previous report (Sayyari et al., 2011).

Water Acids 0.5 % Acids 1.0 % A. vera 50 % A.vera 100 % A. vera 50% + Acids 0.5 % A. vera 100 % + Acids 1.0 %

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With respect to aril firmness, a significant reduction was observed for all treatments, although with significant differences among them (Fig. 2). Thus, the greatest firmness reductions were observed in control arils followed by those treated with acids (at 0.5 or 1.0%), while a significant delay in aril softening was found in those treated with A. vera gel (at 50 or 100%) alone or in combination with acids. These results confirm the role of A. vera gel applied as a coating in delaying postharvest softening that occurs during the normal ripening process, as has been observed for a wide range of fruit including sweet and sour cherry, table grape, strawberry, papaya and nectarine (Valverde et al., 2005; Martínez-Romero et al., 2006; Serrano et al., 2006; Ahmed et al., 2009; Castillo et al., 2010; Vahdat et al., 2010; Marpudi et al., 2011; Navarro et al., 2011; Ravanfar et al., 2012). Other coatings used on pomegranate arils, such as starch, also delayed softening during storage and resulted in lower respiration rates and metabolic activity (Oz and Ulukanli, 2012) Another parameter related to pomegranate quality is colour of the aril (Fig. 2). Hue angle at day 0 (33.44 ± 1.15) experienced a reduction in those arils treated with A. vera gel with the addition of acids (at 0.5 or 1%) as well as in those treated with 1% acids. In contrast, Hue angle increased in control arils during storage and remained unchanged in the arils treated with A. vera gel at both concentrations (50 or 100%) and acids at 0.5%. It is well known that colour of the arils are due to the presence of anthocyanin pigments which increase during postharvest storage of pomegranate fruit and are associated with the maturation process (Mirdehghan et al., 2006; Sayyari et al., 2011). Specifically, in the ‘Mollar de Elche’ cultivar, 5 different anthocyanins

6 0

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Fig. 2. Firmness (N mm−1 ) and colour (Hue angle) of control and treated arils during storage. Data are the mean ± SE of determinations performed in 10 replicates.

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Total Anthocyanins

175

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100

75

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y 0 ter 5% 1% 0% 0% 5% 1% Da W a s 0. cids oe 5 e 10 s 0. cids id A Al Alo Acid +A Ac + % 0% 100 e 5 oe Alo Al

-1

Total Phenolics

Total Anthocyanins (mg 100 g )

-1

Total Phenolics (mg 100 g )

175

111

y 0 ter 5% 1% 0% 0% 5% 1% Da W a s 0. cids oe 5 e 10 s 0. cids id A Al Alo Acid +A Ac + % 0% 100 e 5 oe Alo Al

Treatments (After 8 Days at 3°C) Fig. 3. Total anthocyanins (mg cyanidin 3-glucoside equivalents per 100 g of fresh weight) and total phenolics (mg gallic acid equivalents per 100 g of fresh weight) at day 0 and after 8 days of storage in control and treated arils. Data are the mean ± SE of determinations performed in 10 replicates.

3.3. Microbiological counts Microbial counts at day 0 were 330 ± 77 and 2155 ± 146 CFU g−1 for mesophilic aerobics and yeast and moulds, respectively, and decreased sharply following chlorination (counts below 1 CFU g−1 ). However, significant increases in total mesophilic aerobics and yeast and moulds occurred during storage, the magnitude of the increase being dependent on treatment (Fig. 4), with the exception of treatment of A. vera gel 100% + acids at 1% in which no increase was observed. Generally, A. vera gel treatments had greater effects than acid treatments in delaying the increase in microbial spoilage counts, although the combination of both treatments led to the greatest antimicrobial effects. In previous reports, the antimicrobial activity of A. vera gel in reducing microbial populations and fruit decay has been shown for table grape and sweet cherry (Valverde et al., 2005; Martínez-Romero et al., 2006), the antimicrobial activity of A. vera gel being attributed to the content of aloin (Zapata et al., 2013). Chitosan as another edible coating has also been shown to be effective in reducing spoilage of pomegranate arils (Ghasemnezhad et al., 2013). This effect on reducing microbial counts has also been

observed in table grapes when A. vera gel was used as preharvest treatment (Castillo et al., 2010). 3.4. Sensory evaluation Sensory analyses were performed at each sampling date but results are given fort day 8 of the experiment (Fig. 5), since at this date, control arils were below the limit of acceptability. The scores for colour, aroma, texture and flavour were below 2 in control arils, as well as the scores for purchase decision. In contrast, the highest scores (between 3 and 4) were given to those arils treated with the combination of A. vera gel and acids, especially for A. vera gel 100% + acids at 1%, while arils treated with acids (0.5 or 1%) were at the limit of sensory scores and panellist acceptance. In table grapes, panellists also preferred coated berries with A. vera gel based on crunchiness, firmness, juiciness and visual aspects compared with controls (Valverde et al., 2005), as well as in sweet cherry (Martínez-Romero et al., 2006). In addition, the judges did not perceive any off-flavour in pomegranate arils as a consequence of A. vera gel treatment.

Fig. 4. Mesophilic aerobics and yeast and moulds during storage of control and treated arils. Data are the mean ± SE of determinations performed in 10 replicates.

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Fig. 5. Sensory attributes (flavour, texture, aroma, colour and purchase decision) of control and treated arils after 8 days of storage. Data are the mean of evaluation performed by 10 judges in 10 replicates.

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