Article pp.247-259 du Vol.24 n°3 (2004)

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ARTICLE ORIGINAL ORIGINAL PAPER

Drying performance of five Italian apricot cultivars

A. Piga^1*, M. Poiana², I. Pinna¹, M. Agabbio¹, A. Mincione²

RÉSUMÉ

Performance de séchage de cinq variétés d’abricots italiens

Le séchage d’abricots est réalisé presque exclusivement par énergie solaire.

Cette technologie peut entraîner différents problèmes au point de vue de la qualité et aussi en ce qui concerne l’aspect sanitaire du produit soumis à séchage. Pourtant, la plupart de ces problèmes peut être résolu par le biais d’un séchage contrôlé. Dans ce projet, cinq variétés d’abricots italiens ont été séchés en utilisant un four à air chaud et flux tangentiel.

Avant le séchage, les fruits ont été soumis à un prétraitement au SO₂ pour prévenir le brunissement. Au début du procédé, les fruits ont été échan- tillonnés pour vérifier la perte de qualité du produit et pour mesurer la courbe de séchage. Les résultats montrent que l’utilisation des basses tem- pératures du procédé porte à des cinétiques de séchage plus lente même si les prétraitements réduisent le temps de dessiccation. En outre, les pré- traitements permettent de conserver la couleur des fruits pendant le pro- cédé, sans dépasser, dans la pulpe, les niveaux de SO₂ légaux ; qu’ils permettent d’obtenir une excellente stabilité microbienne. L’analyse senso- rielle a donné de bons résultats même si une des variétés avait un goût légèrement acidulé.

Mots clés

abricot, activité d’eau, cinétique de séchage, qualité de fruit, sulfitation.

SUMMARY

Apricot drying is almost entirely carried out using solar energy. This technology poses concern about the quality and safety of the end product. Control- led drying may solve most of the problems encountered in sun drying.

Apricot fruits of five Italian cultivars underwent hot air drying in a tangential

1. Dipartimento di Scienze Ambientali Agrarie e Biotecnologie Agro-Alimentari, Università degli Studi, Viale Italia 39, 07100 Sassari, Italy.

2. Dipartimento di Biotecnologie per il Monitoraggio Agroalimentare ed Ambientale, Università degli Studi Mediterranea, Piazza San Francesco di Sales 4, 89061 Gallina, Reggio Calabria, Italy.

* Correspondence: [email protected]

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air-flow cabinet dryer. Sampling was done at the beginning and end of the process and at regular intervals throughout, to calculate drying curves and quality loss.

Results showed that mild drying temperatures led to slow drying kinetics, although pre-treatments reduced drying time to a certain extent. Pre-treatments resulted in good colour maintenance during the process, without tres- passing legal limits of SO₂ in the pulp, and microbial stability was excellent.

Sensorial assessment was good, although one of the cultivars resulted in a slightly high acidic taste.

Key words

apricot, drying kinetic, fruit quality, sulfiting, water activity.

1 – INTRODUCTION

Air dehydration is one of the oldest methods by which foods have been pre- served, along with meat and fish salting. Canning, freezing and chilling are the main food stabilisation techniques used nowadays for fruits and vegetables, as dried items no longer satisfied changing consumer demands for convenience and functional foods. However, the increasing need for processing plants to have standardised raw materials and the traditional use of dried fruits has led to a renewed interest in dried products (BARBANTI et al., 1994). Among fruits, apricots are processed in some form on a basis of 40-45% of total world produc- tion (CRIVELLI, 1997). Drying is one of the technologies commonly used (BOLIN et al., 1981). Sun drying is the conventional method, requiring low capital, simple equipment and low energy input. In particular, this method is able to produce apricots of a rich orange colour, translucent appearance and very good gumminess (EL HALOUAT and LABUZA, 1987). Nonetheless, mechanical air dehydration has gained importance because it has many advantages over sun drying, such as the following (BARBOSA-CÁNOVAS and VEGA-MERCADO, 1996): a) the process is carried out under better sanitary conditions as a result of reduced contamination by dust and other foreign matter; b) drying parameters can be accurately set, controlled and changed throughout the process, thus a more uniform product can be achieved with less quality degradation; c) dehydration is not conditioned by rain or weather changes; d) when the dehydration rate becomes constant, increasing the air flow results in shorter drying times; e) labour costs are lower. We also have to remember that Aspergillus spp. fungi contamination is dramatically increased by the contact of apricots with the soil, resulting in higher aflatoxin development. A number of research papers on air dehydration of the main apricot cultivars grown in the world have been published over the last thirty years (BOLIN and STAFFORD, 1974; SANSAVINI et al., 1976; EL HALOUAT

and LABUZA, 1987; SENHAJI et al., 1991; SHARMA et al., 1993), thus data are available on drying kinetics, quality loss and storage potential. On the other hand, few data can be found for the local fruit germplasm, almost completely under-utilised and under risk of extinction in several countries. The south of Italy, in this regard, has a certain number of local apricot cultivars (apart from

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traditional well known varieties such as “Cafona”), and up to now all those stud- ied have proved to be not well suited to drying.

In this paper, the air-drying performance of five local apricot cultivars (three from Apulia and two from Sardinia) is considered, as well as quality changes after processing.

2 – MATERIALS AND METHODS

2.1 Plant material

The Sardinian “Pibirinada bianca” and “Bisucciu” and the Apulian “Crisom- mola piccola”, “Crisommola rossa” and “Crisommola tardiva” were used for the experiment. Fruits were harvested between the end of June and the first decade of July at the proper stage of maturity and immediately transported to the laboratory, where only fruits with no or minimal peel defects were selected. Calibra- tion by weight was performed to have uniform fruit size, so that size would not affect dehydration times within a given cultivar. The cultivars were divided by size. According to the IBPGR-FAO (1984) descriptor list for apricot we have:

Very small fruits: 20g<weight<30 g: Crisommola piccola.

Small fruits: 30g <weight<40 g: Bisucciu, Pibirinada bianca and Crisommola tardiva.

Big fruits: 60g <weight<70 g: Crisommola Rossa.

Before drying, fruits had been pre-treated, in order to reduce enzymatic and non-enzymatic browning and speed up the drying process. Before pre-treating, fruits were cut in half along the suture line with a knife and the stone carefully removed by hand. Pre-treatments were:

1) Blanching in boiling water for 2 minutes, cooling to ambient temperature with tap water and dipping for 3 minutes in a 3% K₂S₂O₅ solution (solution to fruit rate was 7/1 by weight);

2) Dipping for 15 minutes in a 3% K₂S₂O₅ solution (solution to fruit rate was 7/1 by weight);

3) Untreated control.

It was not possible to carry out treatment n.2 on “Crisommola piccola” and

“Crisommola rossa” as we did not have enough fruit material.

The apricots were then dried with paper and air-dried, after damaged fruits had been discarded.

2.2 Drying equipment and process parameters

Fruits were dried in a laboratory pilot dryer. The air drier was a tangential airflow cabinet (a modified model of “Scirocco”, Società Italiana Essiccatoi, Milan, Italy), equipped with automatic temperature and air moisture control devices.

Air flows tangentially to the shelves carrying the fruits, while a particular air

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recycling system allows mixing exhaust air with fresh air and then reheating and redirecting to the product, in order to achieve the desired air moisture. The particular construction of the drier allows a continuous airflow on the fruits, avoid- ing turbulence, and consequently it is particularly suited to calculate drying kinetics. Fruits were placed on steel shelves (product load from 7.5 to 10 kg/m²) using three shelves per treatment (the drier holds ten shelves). Fruits were removed when an estimated 15% water content (based on weight loss calcula- tions) was attained. Processing parameters were as follows:

– Air temperature at ambient conditions = 25˚C – Drying air temperature = 55˚C

– Relative humidity of air at entrance <40%

– Volumetric flow rate = 1840 m³/h

– Air recycling to keep relative humidity below 40%.

Dried fruits were packaged inside water barrier plastic bags (coextruded pol- yethylene/polypropylene, 95 µm of thickness) and stored at –18˚C until analysis.

2.3 Assessments and determinations

A sample of 50 fresh fruits of each cultivar was used to determine mean weight, pulp and stone mean weight, relative percentages, pulp to stone ratio and percentage yield of dried product. Fresh and dried fruits were inspected for water and dry matter content (%), water activity, pH value, total acidity, ascorbic acid and carotenoid content, residual SO₂ and peel colour. Drying kinetics was calculated by plotting the water content revealed at regular intervals during processing versus process times, while drying rates were computed from water loss and process times. In particular, water content was determined in a vacuum oven for 12 h at 70˚C (AOAC, 1990). Water activity of fruit puree was assessed by an electronic hygrometer (model Aw-Win, Rotronic, equipped with a Karl-Fast probe), calibrated in the range 0.1-0.95 with solutions of LiCl of known activity.

The pH was determined after homogenisation of the flesh by a digital pH meter.

The acidity was determined (expressed as mg of malic acid per g of fresh or dried matter) by titration with 0.1N NaOH of homogenised fruit flesh to end point (pH 8.3). Ascorbic acid was determined by HPLC as follows: 10 g of pulp were mixed with 40 mL of 0.05N H₃PO₄ (pH 2.3) and centrifuged at 4000 rpm for 15 minutes. The supernatant was collected and made up to 50 mL with 0.05N H₃PO₄, then 3 mL were passed through a C18 Sep-Pak cartridge previously conditioned with 2 mL of acetonitrile and 5 mL of deionised water. The eluate was filtered through a disposable 0.45 µm filter and then subjected to HPLC analysis with an HP 1050 chromatograph (Palo Alto, California); chromato- graphic conditions were: RP-C18 column at ambient temperature, mobile phase 2% KH₂PO₄ at 0.4 mL/min, sample 20 µL. Detection was carried out at 260 nm and calibration was performed against an external standard. Results are expressed as mg/g of dry matter. Carotenoids were assessed with a spectro- photometer at 450 nm after extraction from fruit puree with a mixture of petrol ether and methanol (90/10 V/V) and subsequent drying with sodium sulphate.

Results are expressed as mg of β-carotene per kg of dry matter. Residual SO₂ was also determined on dried fruits according to AOAC (1990). The peel colour was assessed with a tristimulus colorimeter (Chromameter-2 Reflectance, Minolta, Osaka, Japan), fitted with a CR-300 measuring head. Colour was

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expressed as L, a, b* Hunter scale parameters, and “a” and “b” were used to compute hue angle (tan^-1b*/a*) (LITTLE, 1975). To minimise fruit to fruit variabil- ity, during the process inspection of the colour was always recorded on the same ten fruits chosen at the start of the experiment. A informal panel of six untrained assessors evaluated rehydrated samples on a scale of 1 to 10, on the basis of degree of acceptability. Chemicophysical parameters and colour were subjected to one way analysis of variance (ANOVA) using the MSTAT-C software, considering as the group variable the processing time (fresh and dried), while means were separated, when required, by Multiple Duncan’s range test at P<0,01 level of significance.

3 – RESULTS AND DISCUSSION

Data regarding marketing quality and chemicophysical parameters are shown in tables 1 and 2, respectively. The cultivar “Crisommola piccola”

showed two unfavourable values, the mean weight and the pulp to stone ratio.

We took this cultivar into consideration because of its very low acidity, very similar to that of Turkish cultivars, like Hacihaliloglu (CRIVELLI, 1997). An acid content of more than 0.5% may lead to acid crystallisation and produce sensorial problems in the final product, due to a too acidic taste. This cultivar showed a significantly higher yield of dried material and ascorbic acid content than the others. It must be pointed out that this cultivar had a very good resistance to handling even at full maturity, thus we were able to harvest and process the fruits when they had reached a lower and higher content of acids and dry matter, respectively, compared with the other cultivars (table 2).

Table 1

Main properties of fruits of five Italian apricot cultivars.

Tableau 1

Principales propriétés des fruits de cinq cultivars italiens d’abricot.

Cultivar Property

Mean weight (g)

Pulp mean weight (g)

Stone mean weight (g)

Pulp (%)

Stone (%)

Ratio Pulp/stone

Yield of dried fruits

(%)

Bisucciu 30.15 27.96 2.25 92.5 67.5 12.33 16.3

Pibirinada bianca

38.86 35.34 3.52 90.9 69.1 69.99 18.5

Crisommola rossa

65.16 62.36 3.36 95.7 64.3 22.26 18.9

Crisommola tardiva

31.36 28.56 2.86 91.9 68.1 11.35 18.0

Crisommola piccola

21.36 18.86 2.56 88.3 11.7 67.54 24.2

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Table 2 Chemical-physical characteristics of fresh and dried fruits of five Italian apricot cultivars (fw = fresh weight, dm = dry matter). Tableau 2 Caractéristiques chimiques et physiques de fruits frais et séchés de cinq cultivars italiens d’abricot (fw = poids frais, dm = matière séchée). CultivarSampleDry matter (%)AwpHAcidity (mg malic ac. g fw-1 ) Acidity (mg malic ac. g dm-1 ) Ascorbic acid (mg g dm-1 )

Residual SO2 (mg kg dm-1) Bisucciufresh 14.67c*0.997a3.84a11.9c81.1a19.95a– control, dried 75.15b0.699b4.04a45.1b60.0b43.92b– sulfited92.24a0.571c3.88a58.7a63.6b42.84c261.85a blanched and sulfited91.51a0.595c3.86a59.6a65.1b43.01c210.25b Pibirinada biancafresh19.29c0.990a4.01b11.0d57.0a26.24a– control, dried 77.71b0.725b4.48a19.5c25.1c43.79b– sulfited89.80a0.596c4.47a28.0b31.2c43.05c309.95a blanched and sulfited93.25a0.582c3.92b47.7a51.1b43.03c213.10b Crisommola rossafresh17.31b0.990a3.91a45.6c32.3b21.12a– control, dried 79.37a0.612b3.96a27.1b34.1b43.42b– blanched and sulfited84.13a0.502c4.02a48.9a58.1a42.94c286.14 Crisommola tardivafresh16.49c0.985a3.51a49.1d55.1c25.24a– control, dried 76.31b0.662b3.55a52.3b68.5b43.51b– sulfited82.36a0.527c3.63a67.2a81.5a42.86c272.16a blanched and sulfited85.64a0.461d3.56a46.3c54.1c42.91c254.14a Crisommola piccolafresh22.17c0.982a4.46a42.9c13.1b28.12a– control, dried 72.83b0.751b4.44a15.1b20.7a44.24b– blanched and sulfited86.62a0.452c4.40a441.91a42.2043.52c194.65 * Data followed by different letters within each column and cultivar differ significantly at P<0.01 according to Duncan’s Multiple Range Test. * Les données marquées avec des lettres différentes dans la colonne et dans le cultivar diffèrent de façon significative pour P<0.01, en accord avec le Test Multiple Range de Duncan.

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3.1 Drying kinetics

Figures 1-5 show dehydration kinetics of the five cultivars, Crisommola piccola, Crisommola rossa, Pibirinada bianca, Bisucciu and Crisommola tardiva, respectively. In our experimental conditions, which we can define as mild, as the temperature was quite low compared to the normal processing conditions of other species (BARBANTI et al., 1995; MASTROCOLA et al., 1989), the time to reach the estimated water content ranged from 18 h for the “Crisommola piccola” fruits (Figure 5) to 32 h for the “Crisommola Rossa” cultivar (Figure 3), in accordance with fruit size. “Pibirinada bianca” was the exception (Figure 2). The

“Bisucciu” fruits (Figure 1) showed the highest drying rate (expressed as water loss per unit of time) (data not shown). The pre-treatments were beneficial in lowering drying times (figures 1-5). In fact, both sulfiting alone and blanching plus sulfiting, but mainly the latter, drastically reduced drying times.

Figure 1

Drying kinetics of “Bisucciu” apricot fruits as M (g H₂O/g dry matter) versus drying time (hours). Data are the mean of three determinations

± standard deviation.

Cinétique de déshydratation de « Bisucciu » fruit d’abricot à M (gH₂O/g matière séchée) contre le temps de déshydratation (heures).

Les données représentent la moyenne de trois déterminations

± la déviation standard.

0 1 2 3 4 5 6 7

0 5 10 15 20

Drying time (hours)

Control Sulfited Blanched and sulfited

M(gH2O/g dry matter)

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Figure 2

Drying kinetics of “Pibirinada bianca” apricot fruits as M (g H₂O/g dry matter) versus drying time (hours). Data are the mean of three determinations ± standard deviation.

Cinétique de déshydratation de « Pibirinada bianca » fruit d’abricot à M (gH₂O/g matière séchée) contre le temps de déshydratation (heures). Les données

représentent la moyenne de trois déterminations ± la déviation standard.

Figure 3

Drying kinetics of “Crisommola rossa” apricot fruits as M (g H₂O/g dry matter) versus drying time (hours). Data are the mean of three determinations ± standard deviation.

Cinétique de déshydratation de « Crisommola rossa » fruit d’abricot à M (gH₂O/g matière séchée) contre le temps de déshydratation (heures).

Les données représentent la moyenne de trois déterminations ± la déviation standard.

0 0,5 1 1,5 2 2,5 3 3,5 4 4,5 5

0 5 10 15 20

Drying time (hours)

M (g H2O/g dry matter)

0 1 2 3 4 5 6

0 5 10 15 20 25 30 35

Drying time (hours)

Control Blanched and sulfited

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Figure 4

Drying kinetics of “Crisommola tardiva” apricot fruits as M (g H₂O/g dry matter) versus drying time (hours). Data are the mean

of three determinations ± standard deviation.

Cinétique de déshydratation de « Crisommola tardiva » fruit d’abricot à M (gH₂O/g matière séchée) contre le temps de déshydratation (heures).

Les données représentent la moyenne de trois déterminations ± la déviation standard.

Figure 5

Drying kinetics of “Crisommola piccola” apricot fruits as M (g H₂O/g dry matter) versus drying time (hours). Data are the mean

of three determinations ± standard deviation.

Cinétique de déshydratation de « Crisommola piccola » fruit d’abricot à M (gH₂O/g matière séchée) contre le temps de déshydratation (heures).

Les données représentent la moyenne de trois déterminations ± la déviation standard.

0 1 2 3 4 5

0 5 10 15 20

Drying time (hours)

0 0,5 1 1,5 2 2,5 3 3,5 4

0 5 10 15

Drying time (hours)

Control Blanched and sulfited

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3.2 Chemicophysical and colorimetric changes

Tables 2 and 3 report changes in chemicophysical and colorimetric parameters of fruits after processing. Ascorbic acid and carotenoids underwent a signifi- cant decrease following drying. Loss of the two vitamins due to air-drying has been widely documented (DELLAMONICA and MCDOWELL, 1965; LUND, 1988; RYLEY

and KAJDA, 1993). The main degrading effect can be ascribed to oxidation (we used air to dry) and thermolability of the vitamins (mainly for ascorbic acid), but we cannot exclude the possibility that some ascorbic acid may act as a carbon- ylic substrate in the Maillard reaction (GREGORY, 1993). Ascorbic acid and β-carotene loss ranged from 51 to 89% and from 18 to 48%, respectively. Pre- treatments significantly increased ascorbic acid loss, compared with the untreated assays, in contrast to results indicating otherwise (BOLINAND STAFFORD, 1974), while no effect was observed on β-carotene. Regarding the other chemical parameters, a rise in pH and a decrease in dry matter acidity can be observed in fruits of Sardinian cultivars, with the exception of pH for “Bisucciu”. “Crisommola piccola” fruits showed a final acidity value comparable to that of Turkish dried apricots (MAHMUTOGLU et al., 1996). Aw values were always under the threshold of microbial growth in the pre-treated thesis, therefore we did not assess microbial load. As regards SO₂residues, all fruits treated with SO₂ showed a residual content below Italian legal limits (600 mg/kg) after processing.

Colorimetric data of fresh and processed fruits are reported in table 3. Col- our was strongly influenced by drying. In particular, sulfiting and blanching plus sulfiting resulted in a significantly lower reduction in tonality, expressed as hue angle, with the exception of “Crisommola piccola”. If we look at the single “a”

and “b” factors, a more pronounced shift to a redder and deeper zone in the Hunter solid is evident in the control fruits, a clear sign of non-enzymatic browning (LITTLE, 1975; MASTROCOLAAND LERICI, 1991). Blanched and sulphited

“Crisommola rossa” fruits did not experience any change in the hue angle after processing. Both pre-treatments helped in reducing loss of lightness “L”, with the exception of “Crisommola piccola” cultivar. Our results appear better than those obtained by exposing fruits to SO₂ gas (which had very high amounts of residual SO₂) and then drying them with a solar dryer (MAHMUTOGLU et al., 1996).

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Table 3

Colour parameters of the peel of fresh and dried fruits of five Italian apricot cultivars.

Tableau 3

Paramètres des couleurs de la peau des fruits séchés et frais de cinq cultivars italiens d’abricot.

3.3 Sensorial analysis

Rehydration was needed to make the fruit edible. It was achieved by dipping fruits in boiling water for 3 to 5 minutes, which resulted in fruits having a 30 to 35% water content and a water activity value of 0.75-0.78. The panellists gave very high scores of acceptability at the end of the drying periods (data not shown), as they judged fruits to be excellent for flavour, consistency and chewi- ness. They did not perceive any taste resulting from the Maillard reaction (cook- ing flavour) and gumminess was at acceptable levels. Only “Bisucciu” fruits were judged slightly acid.

Cultivar Colour

Sample L a b Hue angle

(tan^-1 b/a)

Bisucciu fresh 72.92a* – 2.36d 42.27a 93.20a

control, dried 34.34c 10.94a 21.54b 63.08d

sulfited 53.11b 47.69b 45.31a 80.36c

blanched and sulfited 52.92b 44.14c 44.67a 84.70b

Pibirinada bianca fresh 74.43a 4– 0.06d 56.84a 90.06a

control, dried 34.19d 414.28b 23.51c 58.73d

sulfited 41.67c 415.63a 30.94b 63.20c

blanched and sulfited 60.11b 445.02c 58.48a 85.10b

Crisommola rossa fresh 56.78a 425.08a 38.30a 56.78a

control, dried 28.57c 415.76c 12.52c 38.46b

blanched and sulfited 41.64b 419.87b 27.58b 56.62a

Crisommola tardiva fresh 61.82a 44.64c 49.72a 84.66a

control, dried 35.87c 415.27b 21.14c 54.17c

sulfited 40.37b 415.43b 25.76b 59.07b

blanched and sulfited 40.17b 416.31a 27.08b 58.93b

* Data followed by different letters within each column and cultivar differ significantly at P<0.01 according to Duncan’s Multiple Range Test.

* Les données marquées avec des lettres différentes dans la colonne et dans le cultivar diffèrent de façon significative pour P<0.01, en accord avec le Test Multiple Range de Duncan.

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4 – CONCLUSION

Use of mild drying conditions resulted in slow drying kinetics for the five apricot cultivars. Pre-treatments gave faster drying kinetics and better colour preservation, but with greater loss of ascorbic acid compared to the control fruits. Very good microbial stability was achieved only in pre-treated apricots. Very good dehydrated fruits from the sensorial point of view were obtained, especially with the low acid “Crisommola piccola”. Hot air dehydration allows complete control of process parameters and sanitary conditions. However, further studies should be carried out in order to ensure that the quality of the product, especially with regard to colour changes, is main- tained when drying times are reduced.

5 – ACKNOWLEDGEMENTS

Research supported by EE.CC. (FEOGA), Multi Regional Operative Program (POM) “Attività di sostegno ai servizi di sviluppo per l'agricoltura” finanziato dalla Comunita’ Europea and by Italian Government Reg. (C.E.) 2052/88 modified by Reg. C.E. 2081/93 – Quadro Comunitario di Sostegno per le regioni italiane Obiettivo 1, 1994/99. [Dec. C/(95) 2040 -19.10.95], Misura 2

“Innovazioni tecnologiche e trasferimento dei risultati della ricerca”, title of project “Valorizzazione delle risorse frutticole locali mediante tecniche di essiccazione delicate”.

A special thanks to Mrs. Alessandra Nieddu and Mr. Paolo Fenu and Mr. Luigi Conti for helpful technical collaboration.

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SANSAVINI S., CRISTOFERI G., FILITI N., GALLIS A., GRANDI M., SARTI D., 1976.

Ricerche sull'attitudine alla trasformazione industriale delle albicocche (sciroppatura, essiccazione, surgelazione). In: Atti Incontro Frutticolo su Problemi e Prospet- tive della Coltura dell'Albicocco, Società Orticola Italiana, July 1975, 101-122, Imola.

SENHAJI F.A., BIMBENET J.J., HAKAM B., 1991. Data on apricot drying: kinetics and product quality. Sci. Alim., 11, 499-512.

SHARMA T.R., SEKHON K.S., SAINI S.P.S, 1993. Colour changes during drying of apricot. J. Food Sci. Techn. Mys., 30, 306-308.

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cles originaux, des notes de recherche et des revues bibliographiques, en français et en anglais, dans les différents secteurs de la science et de la technologie des aliments.

Les notes de recherche (1 750 mots, 2 illustrations, 10 références bibliographiques) font l'objet d'une procédure de lecture accélérée.

Exclusivité: les auteurs s'engagent à ce que les manuscrits soumis pour publication ne soient pas présentés simultanément à un autre journal scientifique. En dehors du cas de refus définitif, les auteurs s'engagent à ne pas proposer le manuscrit à une autre revue, quelles que soient les modifications demandées par les lecteurs, sans l'accord de la Rédaction.

Les articles sont soumis à l'évaluation de deux lecteurs, spécialistes choisis par le Rédacteur en chef parmi les membres du Comité scientifique ou dési- gnés par lui. Le Rédacteur en chef, responsable de la décision finale, n'est pas tenu de la justifier.

Les manuscritsdoivent être dactylographiés sur papier format 21 ×29,7 cm, en double interligne, au recto seulement avec des marges d'au moins 3,5 cm en haut, en bas et à droite. Les pages doi- vent être numérotéesainsi que les lignes.

Autant que possible joindre au manuscrit accepté une disquette du texte définitif au format Macintosh ou IBM PC 3" 1/2 ou 5" 1/4 en utilisant de préfé- rence un des logiciels suivants : Macwrite, Word, Wordstar, Wordperfect Works, Writenow ou Xywrite. Dans tous les cas, indiquer le matériel utilisé ainsi que le logiciel en précisant sa version. Le texte de la disquette doit être absolument identique au manuscrit.

Au début de chaque mémoire, on indique : le titredu mémoire (il ne doit pas comporter d'abré- viations ni de formules chimiques) : le nom des auteurs précédé du premier prénom en entier et éventuellement des initiales des autres prénoms, le nom des techniciens ayant collaboré à l'étude rela- tée, précédé de la mention : « avec la collaboration technique de… » ; le nom de l'établissement(en toutes lettres) et son adresse ; un titre abrégé (titre courant) de 60 caractères maximum.

Préciser l'adresse pour la correspondance et les tirés à part.

Les mémoires sont rédigés, autant que possible, d'après le plan ci-dessous :

Résumés

Les résumés (moins de 200 mots dans la langue de l'article et moins de 500 dans l'autre langue) doivent être présentés sous une forme adaptée à une exploi-

tation par des services documentaires, en un seul paragraphe, sans renvois en bas de page. Les réfé- rences bibliographiques et les abréviations non défi- nies ne sont pas admises.

Mots clés

Cinq mots clés au plus doivent être fournis, afin de faciliter l'indexation de l'article dans les fichiers documentaires. Les mots clés peuvent provenir du titre, du résumé ou du texte. Eviter le pluriel.

Introduction dans laquelle est indiqué l'objet des recherches entreprises en relation avec les travaux déjà effectués dans ce domaine.

Matériels et méthodesoù, pour les techniques expérimentales et le matériel utilisé, sont donnés sous une forme concise tous les détails nécessaires pour que le lecteur puisse répéter les expériences.

Résultats, à présenter de la manière la plus concise possible.

Discussion Conclusions

Remerciements, le cas échéant pour les collabo- rateurs, les conseils et les aides…

Références bibliographiques(voir ci-après).

Les tableaux et figuresdoivent être fournis à part. Ils font l'objet de deux numérotations dis- tinctes, en chiffres arabes l'une et l'autre. Les légendes des figures, en français et en anglais, sont dactylographiées sur une feuille séparée. Il est demandé d'indiquer sur le manuscrit final, dans la marge, en regard du texte, l'emplace- ment souhaité pour tableaux et figures.

Les tableauxpeuvent être disposés soit dans le sens de la largeur de la revue — et dans ce cas ils ne doivent pas comporter plus de 85 signes par ligne —, soit dans le sens de la longueur. Le nombre des tableaux doit être réduit au profit d'une expression graphique des résultats. Le titre de chaque tableau est porté, en français et en anglais, au-dessus du tableau ; les légendes, en français et en anglais, au- dessous du tableau.

Les figures doivent être fournies à l'état défi- nitif, sur calque ou bristol, pour un clichage direct.

Elles sont préparées en vue d'une réduction de moi- tié, compte tenu de la surface utile du journal : 12,5×19 cm.

Le lettrage (symboles, chiffres, etc.) doit être uni- forme pour toutes les figures et de taille suffisante pour rester lisible après réduction, soit 3 mm mini- mum sur l'original.

Les photographies sont envoyées en 3 exemplaires. Il est recommandé de fournir des épreuves bien contrastées sur papier glacé.

Sciences des Aliments

A N INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY

RECOMMANDATIONS AUX AUTEURS

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Les photos de dessins ou tracés ont un fond blanc.

La publication de figures en couleur est à la charge de l'auteur.

Les unités de mesuresont celles du Système International d'Unités S.I. (cf. Unités de mesures légales, Document International n° 2, OIML ; Norme ISO 1000 ; Norme AFNOR NFX 02-600).

Si une autre unité est jugée indispensable, elle est indiquée entre parenthèses après l'unité du SI. Dans toute la mesure du possible, l'expression en % est à éviter. L'expression « g/100 g » est incorrecte. Les proportions des mélanges en poids ou en volume sont exprimées par les nombres des proportions (par exemple 2:3:3) suivis des grandeurs correspon- dantes (par exemple p:p:v).

Les références bibliographiquesdoivent être citées dans le texte de la manière suivante : (DUPONT et DUVAL, 1993). Lorsque la référence comporte plus de deux auteurs, seul le premier est mentionné suivi de et al.A la fin de l'article, les réfé- rences constituant la bibliographie sont citées par ordre alphabétique des noms des premiers auteurs et par ordre de dates pour un même auteur, sous les formes suivantes :

— article standard dans un périodique TAUREILLES C., ROBIN J.P., FLANZY C., 1992.

Grape (Vitis vinifera L.) malate dehydrogenase.

Partial purification and isoelectric heterogeneity.

Sci. Aliments,12, 649-663.

— ouvrage cité dans son ensemble

BENDER A.E., 1978. Food processing and nutri- tion. Academic Press, London.

— citation d'une partie d'ouvrage

GASTINEAU I., De MATHAN I., 1981. La prépa- ration industrielle de la protéine verte de luzerne.

In: COSTES C. (ed.), Protéines foliaires et ali- mentation, 159-182, Gauthier-Villars, Paris.

— thèse

CUQ J.L., 1981. Modifications chimiques d'acides aminés indispensables sous l'influence de traitements technologiques alimentaires. Thèse de Doctorat d'Etat, Université des Sciences et Techniques du Languedoc, Montpellier.

— Communication (publiée) d'un colloque ou d'un congrès

AUBERT S., 1990. Intérêt des mesures de couleur dans l'amélioration de la qualité des fruits. In: DUPONT J. (ed.), 9^eColloque sur les recherches fruitières, Avignon, 4-6 décembre 1990, 239-246, CTIFL-INRA, Montfavet.

La mention de « communication personnelle » ou

« données non publiées » doit être faite entre paren- thèses dans le texte. Lorsque l'auteur a relevé une référence dans une revue d'abstracts, le mentionner après le titre de l'article et entre parenthèses (abstr.).

— Brevet

CARON J.P., ROUSSEL H., CUQ J.L., ALLIOTTE T., 1989. Procédés d'inactivation des enzymes de détérioration des aliments. Brevet français n° 8911010 du 19 août 1989.

Toutes les références de la liste doivent correspondre à des références citées dans le texte et vice versa.

Les manuscrits revus par les lecteurs et la Rédaction sont retournés aux auteurs. Les textes corrigés par les auteurs en fonction des observations formulées sont renvoyés au Secrétariat de la Rédaction en deux exemplaires. Pour les parties rédigées dans une langue étrangère aux auteurs, la Rédaction se réserve le droit de faire les cor- rectionsfinalesqui lui semblent nécessaires.

Les épreuves d'imprimerie sont envoyées à l'auteur indiqué pour la correspondance.

Elles doivent être soigneusement corrigées et renvoyées dans les 8 jours qui suivent la réception.En cas de retard, l'éditeur se réserve, après sa propre correction, de procéder à l'impres- sion sans les corrections d'auteurs. Si l'auteur requiert des modifications importantes, il en sup- porte la charge financière.

Prestations particulières: la révision linguistique d'un texte, gratuite en français, peut être demandée aux auteurs ou effectuée à leurs frais pour les textes soumis en anglais. Les articles soumis en français peuvent être traduits en anglais par le traducteur scientifique attaché à la revue. Les frais en sont fac- turés aux auteurs. Toutefois, en cas de besoin, une aide financière peut être sollicitée auprès de la Revue, le Comité de Rédaction étant seul juge de l'attribution et du montant de l'aide. Consulter à ce sujet le Secrétariat.

Tirés à part

Un bon de commande est joint aux épreuves.

Copyright: dans le cas d'acceptation pour publication, les auteurs transmettent leurs droits de copyright aux éditeurs du Journal. Toute représentation ou reproduction, intégrale ou partielle (à l'exception des résumés) est illicite sans autorisation préalable de l'éditeur.

Droits de traduction et d'adaptation réservés.

Les manuscrits sont à envoyer en 3 exem- plairesau Secrétariat de la Rédaction :

Chantal Arpino Lavoisier 14, rue de Provigny 94236 Cachan cedex (France)

Tel. + 33 (0)1 47 40 67 66 Fax. + 33 (0)1 47 40 67 02 e-mail : [email protected]

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research notes and reviews in French and English, in various fields of food science and technology.

Research notes(1,750 words, 2 illustrations, 10 references) are subject to an accelerated review procedure.

Exclusivity: manuscripts are accepted for review provided that the same work has not been, and will not be, published or simultaneously submitted elsew- here. Except in cases of refusal, authors are not allowed to submit their manuscript to another journal, whatever the nature of the changes requested by the referees, without the consent of the Editorial Board.

Manuscripts are submitted for review to two expert referees chosen by the Editor-in-Chiefamong the members of the scientific committee, or designated by him. The decision of the Editor-in-Chief is final.

Manuscripts shoud be typeset double-spaced on 21×29.7 cm paper, with margins of at least 3.5 cm at the top, bottom and sides. Only one side of the paper shoud be used. The pages and the lines of the text should be numbered.

Upon acceptance, authors are encouraged, where possible, to include with the printed manuscript the final versionof the article on diskette (Macintosh or IBM PC 3' " or 5' "). Preferred wordprocessing softwares are Macwrite, Word, Wordstar, WordPer- fect, Works, Writenow and Wywrite. In all cases, indicate the computer and software (specify the version) used. Please make sure that the hard copy of your article corresponds exactly to the version on the diskette.

At the beginning of each article, indicate the titleof the article (it should not include abbreviations or chemical formulas), the names of the authors, preceded by the full first name and the ini- tials of the other first names, the names of the technical assistants collaborating in the study, preceded by the words "with the technical assistance of", the full name and address of the institutionwhere the work was done, a short title (running head) limi- ted to 60 letters and spaces.

Specify the address for correspondence and reprint requests.

Articles should be presented in the following form : Summaries

Summaries (not more than 200 words in the language of the article and not exceeding 500 words in the other language) shoud be in a suitable form for abstracting services. Please avoid paragraphs and footnotes. References and undefined abbreviations are not allowed.

Key words

Up to five key words should be supplied to facilitate information retrieval. Key words may be taken from the title, summary or text. Please avoid the plural form.

Introductionindicating the object of the study in relation to previous work in the field.

Materials and methodsused should be given in enough detail to permit the reader to repeat the experiments.

Results, presented as briefly as possible.

Discussion and conclusions.

Acknowledgementsof assistance, advice, support etc.

References

Tables and figuresshould be listed separately and numbered in Arabic numerals. Figure legends should be typed on a separate sheet in French and English.

The ideal position for tables and figures should be indicated in the margin.

Tables must be appropriate for widthwise (not exceeding 85 characters per line) or lengthwise insertion in the journal. Whenever possible tables should be replaced by graphs and their number minimised. The title of each table (in French and English) should be positioned above the table and the legend (in French and English) below the table.

Figures should be in camera-ready formon drawing or tracing paper. They should be prepared so that they can be reduced by half, the usable size of the journal being 12.5 ×19 cm. Lettering (sym- bols, numbers etc.) should not differ from figure to figure and should be of sufficient height (at least 3 mm) and thickness to remain legible after reduction.

Photographs : three sets of photographs are required. Prints must be well contrasted, glossy and of high quality. Photographs of line drawings should have a white background. Authors will be charged for colour prints.

Units of the International System of Units should be used (Legal Units of Measurements, International Document n° 2, OIML ; ISO Standard n° 1000 ; AFNOR Standard NFX 02-600). If another unit is deemed necessary, it should be indicated in parentheses after the SI unit. Inasfar as is possible, the symbol % is to be avoided. The expression

"g/100 g" is incorrect. Mixtures are expressed in proportions (eg. 2:3:3) followed by the cor- responding indications of weight or volume (eg. w:w:v).

Sciences des Aliments

A N INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY

INSTRUCTIONS FOR AUTHORS

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References should be cited in the text as follows (DUPONT and DUVAL, 1954). When there are more than two authors, only the first author should be cited, followed by et al.At the end of the article, references should be listed by authors in alphabetical order and in date order for the same authors in the following form :

— Standard journal article

TAUREILLES C., ROBIN J.P., FLANZY C., 1992.

Grape (Vitis viniferaL.) malate dehydrogenase.

Partial purification and isoelectric heterogeneity.

Sci. Aliments,12, 649-663.

— Book

BENDER A.E., 1978.Food processing and nutri- tion.Academic Press, London.

— Chapter in a book

GASTINEAU I., De MATHAN I., 1981. La prépa- ration industrielle de la protéine verte de luzerne.

In: COSTE C. (ed.), Protéines foliaires et alimen- tation,159-182, Gauthier-Villars, Paris.

— Thesis

CUQ J.L., 1981. Modifications chimiques d'acides aminés indispensables sous l'influence de traitements technologiques alimentaires. Thèse de Doctorat d'Etat, Université des Sciences et Techniques du Languedoc, Montpellier.

— Paper published in conference procee- dings

AUBERT S., 1990. Intérêt des mesures de couleur dans l'amélioration de la qualité des fruits. In: DUPONT J. (ed.), 9^eColloque sur les recherches fruitières,Avignon, 4-6 décembre 1989, 239-246, CTIFL-INRA, Montfavet.

Where necessary, indicate a source by (personal communication) or (unpublished date). When a refe- rence is taken from Abstracts, it should be indicated in parentheses after the title of the article (abstr.).

— Patent

CARON J.P., ROUSSEL H., CUQ J.L., ALLIOTTE T., 1989. Procédés d'inactivation des enzymes de détérioration des aliments. French patent n°

8911010 of 19 August 1989.

All listed references must correspond to references cited in the text and vice versa.

Manuscripts reviewed by the referees and the Editorial Board are returned to the authors. After correction in response to the referees' comments, papers (2 copies) should be returned to the Secretariat. For the parts of the article written in a language different from that of the author's, the journal reserves the right to make the finalcorrections that it deems necessary.

Proofs will be sent to the principal author. They should be carefully corrected and returned within one week of receipt. If this period is exceeded, the editor reserves the right to correct the manuscript and to forward it for publication without the author's corrections. Should substantial changes in the original manuscript be requested, they will be made at the author's expense.

Special services: language revision of a text is free of charge in French. Revision in English will be the responsibility of the author or will be charged for accordingly. Articles submitted in French can be translated into English by the journal's scientific translator. In cases of need, requests for financial help may be considered. The Editorial Board alone will review requests and decide on any sums allotted.

Contact the Secretariat for further details.

Reprints

An order form is sent out with the galley proof.

Copyright: if the manuscript is accepted for publication, copyright will be assigned exclusively to the Publisher. No part of this publication (except summaries) may be reproduced without the prior written consent of the publisher.

Translation and adaptation rights reserved.

Manuscripts (3 copies) should be sent to the Secretariat :

Chantal Arpino Lavoisier 14, rue de Provigny 94236 Cachan cedex (France)

Tel. + 33 (0)1 47 40 67 66 Fax. + 33 (0)1 47 40 67 02 e-mail : [email protected]

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2004

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